Meditation for the primary and secondary prevention of cardiovascular disease

BACKGROUND

Interventions incorporating meditation to address stress, anxiety, and depression, and improve self-management, are becoming popular for many health conditions. Stress is a risk factor for cardiovascular disease (CVD) and clusters with other modifiable behavioural risk factors, such as smoking. Meditation may therefore be a useful CVD prevention strategy.

OBJECTIVES

To determine the effectiveness of meditation, primarily mindfulness-based interventions (MBIs) and transcendental meditation (TM), for the primary and secondary prevention of CVD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases, and two trials registers on 14 November 2021, together with reference checking, citation searching, and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of 12 weeks or more in adults at high risk of CVD and those with established CVD. We explored four comparisons: MBIs versus active comparators (alternative interventions); MBIs versus non-active comparators (no intervention, wait list, usual care); TM versus active comparators; TM versus non-active comparators.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were CVD clinical events (e.g. cardiovascular mortality), blood pressure, measures of psychological distress and well-being, and adverse events. Secondary outcomes included other CVD risk factors (e.g. blood lipid levels), quality of life, and coping abilities. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 81 RCTs (6971 participants), with most studies at unclear risk of bias. MBIs versus active comparators (29 RCTs, 2883 participants) Systolic (SBP) and diastolic (DBP) blood pressure were reported in six trials (388 participants) where heterogeneity was considerable (SBP: MD -6.08 mmHg, 95% CI -12.79 to 0.63, I2 = 88%; DBP: MD -5.18 mmHg, 95% CI -10.65 to 0.29, I2 = 91%; both outcomes based on low-certainty evidence). There was little or no effect of MBIs on anxiety (SMD -0.06 units, 95% CI -0.25 to 0.13; I2 = 0%; 9 trials, 438 participants; moderate-certainty evidence), or depression (SMD 0.08 units, 95% CI -0.08 to 0.24; I2 = 0%; 11 trials, 595 participants; moderate-certainty evidence). Perceived stress was reduced with MBIs (SMD -0.24 units, 95% CI -0.45 to -0.03; I2 = 0%; P = 0.03; 6 trials, 357 participants; moderate-certainty evidence). There was little to no effect on well-being (SMD -0.18 units, 95% CI -0.67 to 0.32; 1 trial, 63 participants; low-certainty evidence). There was little to no effect on smoking cessation (RR 1.45, 95% CI 0.78 to 2.68; I2 = 79%; 6 trials, 1087 participants; low-certainty evidence). None of the trials reported CVD clinical events or adverse events. MBIs versus non-active comparators (38 RCTs, 2905 participants) Clinical events were reported in one trial (110 participants), providing very low-certainty evidence (RR 0.94, 95% CI 0.37 to 2.42). SBP and DBP were reduced in nine trials (379 participants) but heterogeneity was substantial (SBP: MD -6.62 mmHg, 95% CI -13.15 to -0.1, I2 = 87%; DBP: MD -3.35 mmHg, 95% CI -5.86 to -0.85, I2 = 61%; both outcomes based on low-certainty evidence). There was low-certainty evidence of reductions in anxiety (SMD -0.78 units, 95% CI -1.09 to -0.41; I2 = 61%; 9 trials, 533 participants; low-certainty evidence), depression (SMD -0.66 units, 95% CI -0.91 to -0.41; I2 = 67%; 15 trials, 912 participants; low-certainty evidence) and perceived stress (SMD -0.59 units, 95% CI -0.89 to -0.29; I2 = 70%; 11 trials, 708 participants; low-certainty evidence) but heterogeneity was substantial. Well-being increased (SMD 0.5 units, 95% CI 0.09 to 0.91; I2 = 47%; 2 trials, 198 participants; moderate-certainty evidence). There was little to no effect on smoking cessation (RR 1.36, 95% CI 0.86 to 2.13; I2 = 0%; 2 trials, 453 participants; low-certainty evidence). One small study (18 participants) reported two adverse events in the MBI group, which were not regarded as serious by the study investigators (RR 5.0, 95% CI 0.27 to 91.52; low-certainty evidence). No subgroup effects were seen for SBP, DBP, anxiety, depression, or perceived stress by primary and secondary prevention. TM versus active comparators (8 RCTs, 830 participants) Clinical events were reported in one trial (201 participants) based on low-certainty evidence (RR 0.91, 95% CI 0.56 to 1.49). SBP was reduced (MD -2.33 mmHg, 95% CI -3.99 to -0.68; I2 = 2%; 8 trials, 774 participants; moderate-certainty evidence), with an uncertain effect on DBP (MD -1.15 mmHg, 95% CI -2.85 to 0.55; I2 = 53%; low-certainty evidence). There was little or no effect on anxiety (SMD 0.06 units, 95% CI -0.22 to 0.33; I2 = 0%; 3 trials, 200 participants; low-certainty evidence), depression (SMD -0.12 units, 95% CI -0.31 to 0.07; I2 = 0%; 5 trials, 421 participants; moderate-certainty evidence), or perceived stress (SMD 0.04 units, 95% CI -0.49 to 0.57; I2 = 70%; 3 trials, 194 participants; very low-certainty evidence). None of the trials reported adverse events or smoking rates. No subgroup effects were seen for SBP or DBP by primary and secondary prevention. TM versus non-active comparators (2 RCTs, 186 participants) Two trials (139 participants) reported blood pressure, where reductions were seen in SBP (MD -6.34 mmHg, 95% CI -9.86 to -2.81; I2 = 0%; low-certainty evidence) and DBP (MD -5.13 mmHg, 95% CI -9.07 to -1.19; I2 = 18%; very low-certainty evidence). One trial (112 participants) reported anxiety and depression and found reductions in both (anxiety SMD -0.71 units, 95% CI -1.09 to -0.32; depression SMD -0.48 units, 95% CI -0.86 to -0.11; low-certainty evidence). None of the trials reported CVD clinical events, adverse events, or smoking rates.

AUTHORS' CONCLUSIONS

Despite the large number of studies included in the review, heterogeneity was substantial for many of the outcomes, which reduced the certainty of our findings. We attempted to address this by presenting four main comparisons of MBIs or TM versus active or inactive comparators, and by subgroup analyses according to primary or secondary prevention, where there were sufficient studies. The majority of studies were small and there was unclear risk of bias for most domains. Overall, we found very little information on the effects of meditation on CVD clinical endpoints, and limited information on blood pressure and psychological outcomes, for people at risk of or with established CVD. This is a very active area of research as shown by the large number of ongoing studies, with some having been completed at the time of writing this review. The status of all ongoing studies will be formally assessed and incorporated in further updates.

Update on leukodystrophies and developing trials

Leukodystrophies are a heterogeneous group of rare genetic disorders primarily affecting the white matter of the central nervous system. These conditions can present a diagnostic challenge, requiring a comprehensive approach that combines clinical evaluation, neuroimaging, metabolic testing, and genetic testing. While MRI is the main tool for diagnosis, advances in molecular diagnostics, particularly whole-exome sequencing, have significantly improved the diagnostic yield. Timely and accurate diagnosis is crucial to guide symptomatic treatment and assess eligibility to participate in clinical trials. Despite no specific cure being available for most leukodystrophies, gene therapy is emerging as a potential treatment avenue, rapidly advancing the therapeutic prospects in leukodystrophies. This review will explore diagnostic and therapeutic strategies for leukodystrophies, with particular emphasis on new trials.

The efficacy, safety, and immunogenicity of plague vaccines: A systematic literature review

Plague remains endemic in many parts of the world, and despite efforts, no preventative vaccine is available. We performed a systemic review of available randomised controlled trials (RCTs) of live, attenuated, or killed plague vaccines vs. placebo, no intervention, or other plague vaccine to evaluate their efficacy, safety, and immunogenicity. Data sources included MEDLINE, Embase, and the Cochrane Library; clinical trial registers; and reference lists of included studies. Primary outcomes were efficacy, safety, and immunogenicity. Risk of bias was assessed using the Cochrane Collaborations tool. Only 2 RCTs, both on subunit vaccines, were included out of the 75 screened articles. The 2 trials included 240 participants with a follow-up of 3 months and 60 participants with a follow-up of 13 months, respectively. Safety evidence was limited, but both vaccines were well tolerated, with only mild to moderate adverse events. Both vaccines were immunogenic in a dose-dependent manner. However, given the limited data identified in this systematic review, we are unable to quantify the efficacy of vaccines to prevent plague, as well as their long-term safety and immunogenicity. More trials of plague vaccines are needed to generate additional evidence of their long-term effects.

Prolonged respiratory failure responds to conventional therapy in isolated homocysteine remethylation defects

Isolated remethylation defects are rare inherited diseases caused by a defective remethylation of homocysteine to methionine, preventing various essential methylation reactions to occur. Patients present with a systemic phenotype, which can especially affect the central and peripheral nervous systems leading to epileptic encephalopathy, developmental delay and peripheral neuropathy. Respiratory failure has been described in some cases, caused by both central and peripheral neurological involvement. In published cases, the genetic diagnosis and initiation of appropriate therapy were rapidly performed following respiratory failure and led to a rapid recovery of respiratory insufficiency within days. Here, we present two infantile-onset cases of isolated remethylation defects, cobalamine (Cbl)G and methylenetetrahydrofolate reductase (MTHFR) deficiencies, which were diagnosed after several months of respiratory failure. Disease modifying therapy based on hydroxocobalamin and betaine was initiated and shows a progressive improvement and enabled weaning off respiratory support after 21 and 17 months in CblG and MTHFR patients respectively. We show that prolonged respiratory failure responds to conventional therapy in isolated remethylation defects, but can require a sustained period of time before observing a full response to therapy.

Cardiovascular events and risk in patients with systemic lupus erythematosus: Systematic literature review and meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease that typically affects women aged 16-55 years. Cardiovascular disease (CVD) is a well-recognized complication of SLE. This systematic literature review and meta-analysis evaluated the relative risk (RR; compared with non-SLE controls), absolute risk (AR; as incidence proportion, n/N), and incidence rate (IR) of CVD events (including stroke, myocardial infarction [MI], and CVD [composite or undefined]) in adult patients with SLE. The RR of CV risk factors (including hypertension, diabetes, and metabolic syndrome [MetS]) was also examined.

METHODS

PubMed and Embase were searched on September 10, 2020. Observational studies published between January 2010 and September 2020 that reported RR, AR, and/or IR of CVD events, or RR of CV risk factors, were eligible. Pooled risk estimates were calculated using a random-effects model.

RESULTS

Forty-six studies (16 cross-sectional, 15 retrospective cohort, 14 prospective cohort, and 1 case-control) were included in meta-analyses. Most studies were considered high quality (Critical Appraisal Skills Programme checklists). Compared with adults without SLE, patients with SLE had statistically significantly higher RRs (95% CIs) of stroke (2.51 [2.03-3.10]; 12 studies), MI (2.92 [2.45-3.48]; 11 studies), CVD (2.24 [1.94-2.59]; 8 studies), and hypertension (2.70 [1.48-4.92]; 7 studies). RRs of diabetes (1.24 [0.78-1.96]; 3 studies) and MetS (1.49 [0.95-2.33]; 7 studies) were elevated but not significant. RRs of stroke and MI were generally higher in younger versus older patients with SLE. In patients with SLE, the pooled estimate of AR (95% CI) was 0.03 (0.02-0.05), 0.01 (0.00-0.02), and 0.06 (0.03-0.10) for stroke (7 studies), MI (6 studies), and CVD (8 studies), respectively. The pooled estimate of IR per 1000 person-years (95% CI) was 4.72 (3.35-6.32), 2.81 (1.61-4.32), and 11.21 (8.48-14.32) for stroke (10 studies), MI (6 studies), and CVD (8 studies), respectively. Although heterogeneity (based on I² value) was high in most analyses, sensitivity analyses confirmed the robustness of the pooled estimates.

CONCLUSIONS

This meta-analysis found an increased risk of stroke, MI, CVD, and hypertension in patients with SLE compared with the general population, despite substantial heterogeneity across the included studies.

Resilience learning from the COVID-19 pandemic and its relevance for routine immunization programs

INTRODUCTION

The COVID-19 pandemic represents a threat that has posed a challenge to public health response and threatens immunization programs globally. Despite recommendations to continue routine immunization services, disruptions have been observed to these and mass vaccination campaigns. This may result in setbacks to immunization initiative successes and a rise in cases of vaccine-preventable diseases.

AREAS COVERED

We conducted a systematic literature review to identify studies globally that described how indicators of health system resilience, defined using the Resilient Health System Framework, enabled routine immunizations to continue during the COVID-19 pandemic. A systematic search was conducted in Embase, Web of Science, PsychInfo, medRxiv, bioRxiv, and the gray literature between 1 January 2020, and 12 November 2021. Information was extracted from the studies identified describing how the specific elements of resiliency (being aware, diverse, self-regulating, integrated, and adaptive) were applied to their routine immunization programs.

EXPERT OPINION

Our study demonstrates the use of tools that contributed to immunization program resilience during the COVID-19 pandemic in all geographic regions and for countries with different income levels. These tools may help inform preparations for other immunization programs to catch up from the COVID-19 pandemic or mitigate the impact of future threats.

TeenCovidLife: a resource to understand the impact of the COVID-19 pandemic on adolescents in Scotland

TeenCovidLife is part of Generation Scotland's CovidLife projects, a set of longitudinal observational studies designed to assess the psychosocial and health impacts of the COVID-19 pandemic. TeenCovidLife focused on how adolescents in Scotland were coping during the pandemic. As of September 2021, Generation Scotland had conducted three TeenCovidLife surveys. Participants from previous surveys were invited to participate in the next, meaning the age ranges shifted over time. TeenCovidLife Survey 1 consists of data from 5,543 young people age 12 to 17, collected from 22 May to 5 July 2020, during the first school closures period in Scotland. TeenCovidLife Survey 2 consists of data from 2,245 young people aged 12 to 18, collected from 18 August to 14 October 2020, when the initial lockdown measures were beginning to ease, and schools reopened in Scotland. TeenCovidLife Survey 3 consists of data from 597 young people age 12 to 19, collected from 12 May to 27 June 2021, a year after the first survey, after the schools returned following the second lockdown in 2021. A total of 316 participants took part in all three surveys. TeenCovidLife collected data on general health and well-being, as well as topics specific to COVID-19, such as adherence to COVID-19 health guidance, feelings about school closures, and the impact of exam cancellations. Limited work has examined the impact of the COVID-19 pandemic on young people. TeenCovidLife provides relevant and timely data to assess the impact of the pandemic on young people in Scotland. The dataset is available under authorised access from Generation Scotland; see the Generation Scotland website for more information.

TeenCovidLife: a resource to understand the impact of the COVID-19 pandemic on adolescents in Scotland

TeenCovidLife is part of Generation Scotland's CovidLife projects, a set of longitudinal observational studies designed to assess the psychosocial and health impacts of the COVID-19 pandemic. TeenCovidLife focused on how adolescents in Scotland were coping during the pandemic. As of September 2021, Generation Scotland had conducted three TeenCovidLife surveys. Participants from previous surveys were invited to participate in the next, meaning the age ranges shifted over time. TeenCovidLife Survey 1 consists of data from 5,543 young people age 12 to 17, collected from 22 May to 5 July 2020, during the first school closures period in Scotland. TeenCovidLife Survey 2 consists of data from 2,245 young people aged 12 to 18, collected from 18 August to 14 October 2020, when the initial lockdown measures were beginning to ease, and schools reopened in Scotland. TeenCovidLife Survey 3 consists of data from 597 young people age 12 to 19, collected from 12 May to 27 June 2021, a year after the first survey, after the schools returned following the second lockdown in 2021. A total of 316 participants took part in all three surveys. TeenCovidLife collected data on general health and well-being, as well as topics specific to COVID-19, such as adherence to COVID-19 health guidance, feelings about school closures, and the impact of exam cancellations. Limited work has examined the impact of the COVID-19 pandemic on young people. TeenCovidLife provides relevant and timely data to assess the impact of the pandemic on young people in Scotland. The dataset is available under authorised access from Generation Scotland; see the Generation Scotland website for more information.

RuralCovidLife: A new resource for the impact of the pandemic on rural Scotland

RuralCovidLife is part of Generation Scotland’s CovidLife project, investigating the impact of the COVID-19 pandemic and mitigation measures on people in Scotland. The RuralCovidLife project focuses on Scotland’s rural communities, and how they have been impacted by the pandemic. During survey development, Generation Scotland consulted with people living or working in rural communities, and collaborated with a patient and public involvement and engagement (PPIE) group composed of rural community leaders. Through this consultation work, the RuralCovidLife survey was developed to assess the issues most pertinent to people in rural communities, such as mental health, employment, transport, connectivity, and local communities. Between 14th October and 30th November 2020, 3,365 participants from rural areas in Scotland took part in the survey. Participant ages ranged from 16 to 96 (mean = 58.4, standard deviation [SD] = 13.3), and the majority of the participants were female (70.5%). Over half (51.3%) had taken part in the original CovidLife survey. RuralCovidLife includes a subsample (n = 523) of participants from the Generation Scotland cohort. Pre-pandemic data on health and lifestyle, as well as biological samples, are available for these participants. These participants’ data can also be linked to past and future healthcare records, allowing analysis of retrospective and prospective health outcomes. Like Generation Scotland, RuralCovidLife is designed as a resource for researchers. RuralCovidLife data, as well as the linked Generation Scotland data, is available for use by external researchers following approval from the Generation Scotland Access Committee. RuralCovidLife can be used to investigate mental health, well-being, and behaviour in participants living in rural areas during the COVID-19 pandemic, as well as comparisons with non-rural samples. Moreover, the sub-sample with full Generation Scotland data and linkage can be used to investigate the long-term health consequences of the COVID-19 pandemic in rural communities.

Subcutaneous immunoglobulin use in immunoglobulin-naive patients with primary immunodeficiency: a systematic review

Aim: Identify and describe published literature on the use of subcutaneous immunoglobulin (SCIG) as initial immunoglobulin (IG)-replacement therapy for patients with primary immunodeficiency diseases (PID). Methods: We systematically identified and summarized literature in MEDLINE, Embase, BioSciences Information Service and Cochrane Library assessing efficacy/effectiveness, safety/tolerability, health-related quality-of-life (HRQoL) and dosing regimens of SCIG for IG-naive patients with PID. Results: Sixteen studies were included. In IG-naive patients, SCIG managed/reduced infections and demonstrated similar pharmacokinetic parameters to IG-experienced patients; adverse events were mostly minor injection-site pain or discomfort. Three studies reported improvements in HRQoL. Quality of studies was difficult to assess due to limited reporting. Conclusion: Although studies were lacking, available data suggest IG-naive and IG-experienced patients initiating SCIG likely have similar outcomes.

RuralCovidLife: Study protocol and description of the data

RuralCovidLife is part of Generation Scotland’s CovidLife project, investigating the impact of the COVID-19 pandemic and mitigation measures on people in Scotland. The RuralCovidLife project focuses on Scotland’s rural communities, and how they have been impacted by the pandemic. During survey development, Generation Scotland consulted with people living or working in rural communities, and collaborated with a patient and public involvement and engagement (PPIE) group composed of rural community leaders. Through this consultation work, the RuralCovidLife survey was developed to assess the issues most pertinent to people in rural communities, such as mental health, employment, transport, connectivity, and local communities. Between 14th October and 30th November 2020, 3,365 participants from rural areas in Scotland took part in the survey. Participant ages ranged from 16 to 96 (mean = 58.4, standard deviation [SD] = 13.3), and the majority of the participants were female (70.5%). Over half (51.3%) had taken part in the original CovidLife survey. RuralCovidLife includes a subsample (n = 523) of participants from the Generation Scotland cohort. Pre-pandemic data on health and lifestyle, as well as biological samples, are available for these participants. These participants’ data can also be linked to past and future healthcare records, allowing analysis of retrospective and prospective health outcomes. Like Generation Scotland, RuralCovidLife is designed as a resource for researchers. RuralCovidLife data, as well as the linked Generation Scotland data, is available for use by external researchers following approval from the Generation Scotland Access Committee. RuralCovidLife can be used to investigate mental health, well-being, and behaviour in participants living in rural areas during the COVID-19 pandemic, as well as comparisons with non-rural samples. Moreover, the sub-sample with full Generation Scotland data and linkage can be used to investigate the long-term health consequences of the COVID-19 pandemic in rural communities.

Impact of the introduction of an integrated multi-professional pathway for atrial fibrillation on long-term outcomes

Background

An integrated structured approach to atrial fibrillation (AF) management is recommended by ESC.1 However, limited data is available on its “real-world” impact on anticoagulation uptake and subsequent AF-related hospitalisation and stroke rates.

Purpose

To evaluate the long-term impact of the introduction of a community-wide integrated AF service based in a secondary care hospital.

Methods

In September 2017 we implemented a new integrated pathway for patients with newly diagnosed “symptomatic” atrial arrhythmias across two regions (population 450,000) in England in collaboration with primary care. All patients were seen in a one-stop multi-professional clinic (Arrhythmia nurse and Electrophysiologist with ECG and echocardiogram) within 2 weeks. They underwent standardised screening for modifiable risk factors, counselling regarding diagnosis/ anticoagulation and received an individualised AF management plan as well as access to a nurse-led telephone helpline. We followed up the first 126 consecutive patients for a period of 12 months.

Results

Baseline characteristics are shown in Table 1, showing a high incidence of modifiable risk factors (previously un-identified in the majority). After review in clinic, 30-day AF-related readmission rates to hospital were low (1.6%, n=2) as compared to historical local data (5.8%). This was sustained at 3 months (4.7%, n=6) and at 12 months (7.9%, n=10). 99% of 83 of eligible patients (CHA2DS2-VASc score of >2 with no major contra-indications) received oral anticoagulation. Over 12 months follow-up, rates of TIA/stroke was low (n=3, 2.4%). All-cause mortality was also low (n=1, 0.8%). NHS England region-wide data showed a marked reduction in percentage of total stroke admissions with history of AF not taking anticoagulation at stroke presentation in 2018/19 as compared to 2017/18 across our two regions; this was lower than the national average and the lowest within West Yorkshire (Figure 1).

Conclusions

An integrated service for AF management implemented community-wide was associated with high uptake of oral anticoagulation among eligible patients and low rates of AF-related hospitalisations and all-cause mortality. Across the community, among stroke admissions with AF at presentation, a lower percentage of patients without anticoagulation was observed in comparison with previous years and neighbouring regions.

Funding Acknowledgement

Type of funding sources: None.

CovidLife: a resource to understand mental health, well-being and behaviour during the COVID-19 pandemic in the UK

CovidLife is a longitudinal observational study designed to investigate the impact of the COVID-19 pandemic on mental health, well-being and behaviour in adults living in the UK. In total, 18,518 participants (mean age = 56.43, SD = 14.35) completed the first CovidLife questionnaire (CovidLife1) between April and June 2020. To date, participants have completed two follow-up assessments. CovidLife2 took place between July and August 2020 (n = 11,319), and CovidLife3 took place in February 2021 (n = 10,386). A range of social and psychological measures were administered at each wave including assessments of anxiety, depression, well-being, loneliness and isolation. Information on sociodemographic, health, and economic circumstances was also collected. Questions also assessed information on COVID-19 infections and symptoms, compliance to COVID-19 restrictions, and opinions on the UK and Scottish Governments' handling of the pandemic. CovidLife includes a subsample of 4,847 participants from the Generation Scotland cohort (N~24,000, collected 2006-2011); a well-characterised cohort of families in Scotland with pre-pandemic data on mental health, physical health, lifestyle, and socioeconomic factors, along with biochemical and genomic data derived from biological samples. These participants also consented to their study data being linked to Scottish health records. CovidLife and Generation Scotland data can be accessed and used by external researchers following approval from the Generation Scotland Access Committee. CovidLife can be used to investigate mental health, well-being and behaviour during COVID-19; how these vary according to sociodemographic, health and economic circumstances; and how these change over time. The Generation Scotland subsample with pre-pandemic data and linkage to health records can be used to investigate the predictors of health and well-being during COVID-19 and the future health consequences of the COVID-19 pandemic.

Speckled brain lesions in Incontinentia Pigmenti patients with acquired brain syndromes

Incontinentia Pigmenti (IP) is a neurocutaneous syndrome, with malformations of cortical development and neurodevelopmental delay in some patients. Neonates with IP may develop acute encephalopathy with multifocal ischemic brain lesions with a speckled pattern on diffusion-weighted magnetic resonance imaging (MRI). We observed a similar MRI pattern in 4 female patients with IP who presented with childhood acute encephalopathy syndromes. These patients, aged 9 days to 13 years old, had acute neonatal encephalitis, Influenza A virus related acute necrotizing encephalopathy (ANE) of childhood, Influenza B virus related acute encephalopathy with biphasic seizures and late restricted diffusion (AESD) and acute disseminated encephalitis (ADEM) with transverse myelitis (TM). These lesions could possibly reflect the white matter changes in IP patients with encephalopathy.

Socioeconomic position and mental health during the COVID-19 pandemic: a cross-sectional analysis of the CovidLife study

Background: The coronavirus disease 2019 (COVID-19) pandemic has been linked to an increase in mental health problems. This study examined their association with socioeconomic position (SEP), as well as potential confounding and mediating factors. Methods: We analysed data from the CovidLife study (N=14,387; 66.4% female; mean [SD] age, 57.4 [13.9] years). Data were collected in an online survey of UK adults (aged 18 years or over) between 17 April and 7 June 2020. SEP measures included area deprivation (the Scottish Index of Multiple Deprivation [SIMD]), education level, household income, and employment status. Mental health was measured using the Patient Health Questionnaire-9 (PHQ-9) and the Generalised Anxiety Disorder-7 (GAD-7) scale. Worry indices were derived using principal component analysis. Logistic regression was used to estimate the associations between SEP and mental health. Results: Low SEP was associated with increased odds of depression and anxiety (odds ratio [OR] range 1.18-2.69). These associations remained significant after adjusting for age, sex, relationship status, and psychiatric history. Multivariable adjustment for medical worry and isolation during the pandemic had the largest attenuating effects (ranges 18-60% and 4-46%, respectively) on mental health outcomes. When adding further adjustment for the remaining SEP markers and all potential confounding and mediating factors, depression was associated with high area deprivation and low education level and income, whilst anxiety was only associated with low education level. No dose-response relationship was observed. Conclusions: SEP was inversely associated with mental health, which was mostly explained by medical worry and isolation during the COVID-19 pandemic. Mental health interventions might target these factors to prevent widening inequalities in mental health. Future studies should use longitudinal data to investigate the association.

Face covering adherence is positively associated with better mental health and wellbeing: a longitudinal analysis of the CovidLife surveys

Background: Face masks or coverings are effective at reducing airborne infection rates, yet pandemic mitigation measures, including wearing face coverings, have been suggested to contribute to reductions in quality of life and poorer mental health. Complaints of inconvenience, discomfort, and other issues have been repeatedly and loudly voiced by critics, and adherence in many nations is not strong enough to suppress viral spread. We wished to see whether wearing face coverings is associated with mental health and wellbeing. Methods: We analysed survey 1 and 2 of the CovidLife study, a sample of more than 18,000 individuals living in the UK. The study asked a variety of questions about participants’ psychological, economic, and social lives while living under the coronavirus disease 2019 (COVID-19) pandemic in 2020. We measured individuals’ adherence to following guidance on wearing face coverings, as well as several mental health outcomes: depression, anxiety, wellbeing, life satisfaction, and loneliness. Results: We found no association between lower adherence to face covering guidelines and poorer mental health. The opposite appears to be true. Even after controlling for behavioural, social, and psychological confounds, including measures of pre-pandemic mental health, individuals who wore face coverings “most of the time” or “always” had better mental health and wellbeing than those who did not. Individuals who wore masks only “some of the time” or “never” tended to be male, lower income, and already had COVID-19 or COVID-19-like symptoms. Conclusions: These results suggest that wearing face coverings more often does not negatively impact mental health. Wearing a face covering more often is actually linked to better mental health and wellbeing. Implications are discussed and we highlight the potential pathways for addressing a lack of face covering that this study reveals.

P5308Mediterranean-style diet for the primary and secondary prevention of cardiovascular disease: Cochrane systematic review and meta-analysis of randomised clinical trials

Background

Observational studies have confirmed the benefits of adherence to a Mediterranean dietary pattern on cardiovascular disease (CVD) but the randomised controlled trial (RCT) evidence is limited.

Objective

To determine the effectiveness of a Mediterranean-style diet for the primary and secondary prevention of CVD.

Methods

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Web of Science, DARE, HTA, NHS EED and trial registers (September 2018). We selected RCTs in healthy adults and adults at high risk of CVD (primary prevention) and those with established CVD (secondary prevention). Both of the following key components were required for our definition of a Mediterranean-style diet: high monounsaturated/saturated fat ratio and a high intake of plant based foods, including fruits, vegetables, and legumes. The intervention could be dietary advice, provision of relevant foods or both. The comparison group received either no intervention, minimal intervention, usual care or another dietary intervention. Outcomes included clinical events and CVD risk factors. We included only studies with follow-up periods of 3 months or more.

Results

Overall, 30 RCTs (12,461 participants randomised) and 7 ongoing trials met our inclusion criteria, whereas 22 primary prevention trials and 6 secondary prevention trials were analysed. Low quality evidence shows little or no effect of the PREDIMED (7747 randomised) intervention (advice to follow a Mediterranean diet plus supplemental extra virgin olive oil or tree nuts) compared to a low fat diet on CVD mortality (HR 0.81 (95% CI 0.5, 1.32)) or total mortality (HR 1.0 (95% CI 0.81, 1.24)) over 4.8 years. There was however a reduction in the number of strokes with the PREDIMED intervention (HR 0.6 (95% CI 0.45, 0.8), moderate quality evidence). For secondary prevention, in the Lyon Diet Heart Study (605 CVD patients), there was moderate quality evidence of a reduction in CVD mortality (HR 0.35 (95% CI 0.15, 0.82)) and total mortality (HR 0.44 (95% CI 0.21, 0.92)) with the intervention, over 46 months. For CVD risk factors, in primary prevention trials, there was low quality evidence for a possible small reduction in total cholesterol (−0.16 mmol/L (95% CI −0.32, 0.00), and moderate quality evidence for a reduction in SBP (−2.99 mmHg (95% CI −3.45, −2.53)) and DBP (−2.0 mmHg (95% CI −2.29, −1.71)). In secondary prevention trials, there was moderate quality evidence of no effect of a Mediterranean-style diet on lipid levels and low or very low quality evidence for blood pressure.

Conclusions

Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The ongoing studies may provide more certainty in the future.

Mediterranean-style diet for the primary and secondary prevention of cardiovascular disease

BACKGROUND

The Seven Countries study in the 1960s showed that populations in the Mediterranean region experienced lower coronary heart disease (CHD) mortality probably as a result of different dietary patterns. Later observational studies have confirmed the benefits of adherence to a Mediterranean dietary pattern on cardiovascular disease (CVD) risk factors but clinical trial evidence is more limited.

OBJECTIVES

To determine the effectiveness of a Mediterranean-style diet for the primary and secondary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 9); MEDLINE (Ovid, 1946 to 25 September 2018); Embase (Ovid, 1980 to 2018 week 39); Web of Science Core Collection (Thomson Reuters, 1900 to 26 September 2018); DARE Issue 2 of 4, 2015 (Cochrane Library); HTA Issue 4 of 4, 2016 (Cochrane Library); NHS EED Issue 2 of 4, 2015 (Cochrane Library). We searched trial registers and applied no language restrictions.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) in healthy adults and adults at high risk of CVD (primary prevention) and those with established CVD (secondary prevention). Both of the following key components were required to reach our definition of a Mediterranean-style diet: high monounsaturated/saturated fat ratio (use of olive oil as main cooking ingredient and/or consumption of other traditional foods high in monounsaturated fats such as tree nuts) and a high intake of plant-based foods, including fruits, vegetables and legumes. Additional components included: low to moderate red wine consumption; high consumption of whole grains and cereals; low consumption of meat and meat products and increased consumption of fish; moderate consumption of milk and dairy products. The intervention could be dietary advice, provision of relevant foods, or both. The comparison group received either no intervention, minimal intervention, usual care or another dietary intervention. Outcomes included clinical events and CVD risk factors. We included only studies with follow-up periods of three months or more defined as the intervention period plus post intervention follow-up.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, extracted data and assessed risk of bias. We conducted four main comparisons:1. Mediterranean dietary intervention versus no intervention or minimal intervention for primary prevention;2. Mediterranean dietary intervention versus another dietary intervention for primary prevention;3. Mediterranean dietary intervention versus usual care for secondary prevention;4. Mediterranean dietary intervention versus another dietary intervention for secondary prevention.

MAIN RESULTS

In this substantive review update, 30 RCTs (49 papers) (12,461 participants randomised) and seven ongoing trials met our inclusion criteria. The majority of trials contributed to primary prevention: comparisons 1 (nine trials) and 2 (13 trials). Secondary prevention trials were included for comparison 3 (two trials) and comparison 4 (four trials plus an additional two trials that were excluded from the main analyses due to published concerns regarding the reliability of the data).Two trials reported on adverse events where these were absent or minor (low- to moderate-quality evidence). No trials reported on costs or health-related quality of life.Primary preventionThe included studies for comparison 1 did not report on clinical endpoints (CVD mortality, total mortality or non-fatal endpoints such as myocardial infarction or stroke). The PREDIMED trial (included in comparison 2) was retracted and re-analysed following concerns regarding randomisation at two of 11 sites. Low-quality evidence shows little or no effect of the PREDIMED (7747 randomised) intervention (advice to follow a Mediterranean diet plus supplemental extra-virgin olive oil or tree nuts) compared to a low-fat diet on CVD mortality (hazard ratio (HR) 0.81, 95% confidence interval (CI) 0.50 to 1.32) or total mortality (HR 1.0, 95% CI 0.81 to 1.24) over 4.8 years. There was, however, a reduction in the number of strokes with the PREDIMED intervention (HR 0.60, 95% CI 0.45 to 0.80), a decrease from 24/1000 to 14/1000 (95% CI 11 to 19), moderate-quality evidence). For CVD risk factors for comparison 1 there was low-quality evidence for a possible small reduction in total cholesterol (-0.16 mmol/L, 95% CI -0.32 to 0.00) and moderate-quality evidence for a reduction in systolic (-2.99 mmHg (95% CI -3.45 to -2.53) and diastolic blood pressure (-2.0 mmHg, 95% CI -2.29 to -1.71), with low or very low-quality evidence of little or no effect on LDL or HDL cholesterol or triglycerides. For comparison 2 there was moderate-quality evidence of a possible small reduction in LDL cholesterol (-0.15 mmol/L, 95% CI -0.27 to -0.02) and triglycerides (-0.09 mmol/L, 95% CI -0.16 to -0.01) with moderate or low-quality evidence of little or no effect on total or HDL cholesterol or blood pressure.Secondary preventionFor secondary prevention, the Lyon Diet Heart Study (comparison 3) examined the effect of advice to follow a Mediterranean diet and supplemental canola margarine compared to usual care in 605 CHD patients over 46 months and there was low-quality evidence of a reduction in adjusted estimates for CVD mortality (HR 0.35, 95% CI 0.15 to 0.82) and total mortality (HR 0.44, 95% CI 0.21 to 0.92) with the intervention. Only one small trial (101 participants) provided unadjusted estimates for composite clinical endpoints for comparison 4 (very low-quality evidence of uncertain effect). For comparison 3 there was low-quality evidence of little or no effect of a Mediterranean-style diet on lipid levels and very low-quality evidence for blood pressure. Similarly, for comparison 4 where only two trials contributed to the analyses there was low or very low-quality evidence of little or no effect of the intervention on lipid levels or blood pressure.

AUTHORS' CONCLUSIONS

Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in primary prevention is low or moderate, with a small number of studies reporting minimal harms. There is a paucity of evidence for secondary prevention. The ongoing studies may provide more certainty in the future.

WITHDRAWN: Transcendental meditation for the primary prevention of cardiovascular disease

BACKGROUND

A major determinant in cardiovascular disease (CVD) is stress. As transcendental meditation (TM) is thought to help in lowering negative stress indicators, it may be a beneficial strategy for the primary prevention of CVD.

OBJECTIVES

To determine the effectiveness of TM for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 10); MEDLINE (Ovid) (1946 to week three November 2013); EMBASE Classic and EMBASE (Ovid) (1947 to week 48 2013); ISI Web of Science (1970 to 28 November 2013); and Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment Database and Health Economics Evaluations Database (November 2013). We also searched the Allied and complementary Medicine Database (AMED) (inception to January 2014) and IndMed (inception to January 2014). We handsearched trial registers and reference lists of reviews and articles and contacted experts in the field. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of at least three months' duration involving healthy adults or adults at high risk of CVD. Trials examined TM only and the comparison group was no intervention or minimal intervention. We excluded trials that involved multi-factorial interventions. Outcomes of interest were clinical CVD events (cardiovascular mortality, all-cause mortality and non-fatal events) and major CVD risk factors (e.g. blood pressure and blood lipids, occurrence of type 2 diabetes, quality of life, adverse events and costs).

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion, extracted data and assessed the risk of bias.

MAIN RESULTS

We identified four trials (four papers) (430 participants) for inclusion in this review. We identified no ongoing studies. The included trials were small, short term (three months) and at risk of bias. In all studies, TM was practised for 15 to 20 minutes twice a day.None of the included studies reported all-cause mortality, cardiovascular mortality or non-fatal endpoints as trials were short term, but one study reported survival rate three years after the trial was completed. In view of the considerable statistical heterogeneity between the results of the studies for the only outcomes reported, systolic blood pressure (I2 = 72%) and diastolic blood pressure (I2 = 66%), we decided not to undertake a meta-analysis. None of the four trials reported blood lipids, occurrence of type 2 diabetes, adverse events, costs or quality of life.

AUTHORS' CONCLUSIONS

Currently, there are few trials with limited outcomes examining the effectiveness of TM for the primary prevention of CVD. Due to the limited evidence to date, we could draw no conclusions as to the effectiveness of TM for the primary prevention of CVD. There was considerable heterogeneity between trials and the included studies were small, short term and at overall serious risk of bias. More and larger long-term, high-quality trials are needed.

Whole grain cereals for the primary or secondary prevention of cardiovascular disease

BACKGROUND

There is evidence from observational studies that whole grains can have a beneficial effect on risk for cardiovascular disease (CVD). Earlier versions of this review found mainly short-term intervention studies. There are now longer-term randomised controlled trials (RCTs) available. This is an update and expansion of the original review conducted in 2007.

OBJECTIVES

The aim of this systematic review was to assess the effect of whole grain foods or diets on total mortality, cardiovascular events, and cardiovascular risk factors (blood lipids, blood pressure) in healthy people or people who have established cardiovascular disease or related risk factors, using all eligible RCTs.

SEARCH METHODS

We searched CENTRAL (Issue 8, 2016) in the Cochrane Library, MEDLINE (1946 to 31 August 2016), Embase (1980 to week 35 2016), and CINAHL Plus (1937 to 31 August 2016) on 31 August 2016. We also searched ClinicalTrials.gov on 5 July 2017 and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) on 6 July 2017. We checked reference lists of relevant articles and applied no language restrictions.

SELECTION CRITERIA

We selected RCTs assessing the effects of whole grain foods or diets containing whole grains compared to foods or diets with a similar composition, over a minimum of 12 weeks, on cardiovascular disease and related risk factors. Eligible for inclusion were healthy adults, those at increased risk of CVD, or those previously diagnosed with CVD.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies. Data were extracted and quality-checked by one review author and checked by a second review author. A second review author checked the analyses. We assessed treatment effect using mean difference in a fixed-effect model and heterogeneity using the I² statistic and the Chi² test of heterogeneity. We assessed the overall quality of evidence using GRADE with GRADEpro software.

MAIN RESULTS

We included nine RCTs randomising a total of 1414 participants (age range 24 to 70; mean age 45 to 59, where reported) to whole grain versus lower whole grain or refined grain control groups. We found no studies that reported the effect of whole grain diets on total cardiovascular mortality or cardiovascular events (total myocardial infarction, unstable angina, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, total stroke). All included studies reported the effect of whole grain diets on risk factors for cardiovascular disease including blood lipids and blood pressure. All studies were in primary prevention populations and had an unclear or high risk of bias, and no studies had an intervention duration greater than 16 weeks.Overall, we found no difference between whole grain and control groups for total cholesterol (mean difference 0.07, 95% confidence interval -0.07 to 0.21; 6 studies (7 comparisons); 722 participants; low-quality evidence).Using GRADE, we assessed the overall quality of the available evidence on cholesterol as low. Four studies were funded by independent national and government funding bodies, while the remaining studies reported funding or partial funding by organisations with commercial interests in cereals.

AUTHORS' CONCLUSIONS

There is insufficient evidence from RCTs of an effect of whole grain diets on cardiovascular outcomes or on major CVD risk factors such as blood lipids and blood pressure. Trials were at unclear or high risk of bias with small sample sizes and relatively short-term interventions, and the overall quality of the evidence was low. There is a need for well-designed, adequately powered RCTs with longer durations assessing cardiovascular events as well as cardiovascular risk factors.

Low glycaemic index diets for the prevention of cardiovascular disease

BACKGROUND

The glycaemic index (GI) is a physiological measure of the ability of a carbohydrate to affect blood glucose. Interest is growing in this area for the clinical management of people at risk of, or with, established cardiovascular disease. There is a need to review the current evidence from randomised controlled trials (RCTs) in this area. This is an update of the original review published in 2008.

OBJECTIVES

To assess the effect of the dietary GI on total mortality, cardiovascular events, and cardiovascular risk factors (blood lipids, blood pressure) in healthy people or people who have established cardiovascular disease or related risk factors, using all eligible randomised controlled trials.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and CINAHL in July 2016. We also checked reference lists of relevant articles. No language restrictions were applied.

SELECTION CRITERIA

We selected RCTs that assessed the effects of low GI diets compared to diets with a similar composition but a higher GI on cardiovascular disease and related risk factors. Minimum trial duration was 12 weeks. Participants included were healthy adults or those at increased risk of cardiovascular disease, or previously diagnosed with cardiovascular disease. Studies in people with diabetes mellitus were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently screened and selected studies. Two review authors independently assessed risk of bias, evaluated the overall quality of the evidence using GRADE, and extracted data following the Cochrane Handbook for Systematic Reviews of Interventions. We contacted trial authors for additional information. Analyses were checked by a second reviewer. Continuous outcomes were synthesized using mean differences and adverse events were synthesized narratively.

MAIN RESULTS

Twenty-one RCTs were included, with a total of 2538 participants randomised to low GI intervention (1288) or high GI (1250). All 21 included studies reported the effect of low GI diets on risk factors for cardiovascular disease, including blood lipids and blood pressure.Twenty RCTs (18 of which were newly included in this version of the review) included primary prevention populations (healthy individuals or those at high risk of CVD, with mean age range from 19 to 69 years) and one RCT was in those diagnosed with pre-existing CVD (a secondary prevention population, with mean age 26.9 years). Most of the studies did not have an intervention duration of longer than six months. Difference in GI intake between comparison groups varied widely from 0.6 to 42.None of the included studies reported the effect of low GI dietary intake on cardiovascular mortality and cardiovascular events such as fatal and nonfatal myocardial infarction, unstable angina, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, and stroke. The unclear risk of bias of most of the included studies makes overall interpretation of the data difficult. Only two of the included studies (38 participants) reported on adverse effects and did not observe any harms (low-quality evidence).

AUTHORS' CONCLUSIONS

There is currently no evidence available regarding the effect of low GI diets on cardiovascular disease events. Moreover, there is currently no convincing evidence that low GI diets have a clear beneficial effect on blood lipids or blood pressure parameters.

Vitamin C supplementation for the primary prevention of cardiovascular disease

BACKGROUND

Vitamin C is an essential micronutrient and powerful antioxidant. Observational studies have shown an inverse relationship between vitamin C intake and major cardiovascular events and cardiovascular disease (CVD) risk factors. Results from clinical trials are less consistent.

OBJECTIVES

To determine the effectiveness of vitamin C supplementation as a single supplement for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases on 11 May 2016: the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library; MEDLINE (Ovid); Embase Classic and Embase (Ovid); Web of Science Core Collection (Thomson Reuters); Database of Abstracts of Reviews of Effects (DARE); Health Technology Assessment Database and Health Economics Evaluations Database in the Cochrane Library. We searched trial registers on 13 April 2016 and reference lists of reviews for further studies. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of vitamin C supplementation as a single nutrient supplement lasting at least three months and involving healthy adults or adults at moderate and high risk of CVD were included. The comparison group was no intervention or placebo. The outcomes of interest were CVD clinical events and CVD risk factors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias.

MAIN RESULTS

We included eight trials with 15,445 participants randomised. The largest trial with 14,641 participants provided data on our primary outcomes. Seven trials reported on CVD risk factors. Three of the eight trials were regarded at high risk of bias for either reporting or attrition bias, most of the 'Risk of bias' domains for the remaining trials were judged as unclear, with the exception of the largest trial where most domains were judged to be at low risk of bias.The composite endpoint, major CVD events was not different between the vitamin C and placebo group (hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.89 to 1.10; 1 study; 14,641 participants; low-quality evidence) in the Physicians Health Study II over eight years of follow-up. Similar results were obtained for all-cause mortality HR 1.07, 95% CI 0.97 to 1.18; 1 study; 14,641 participants; very low-quality evidence, total myocardial infarction (MI) (fatal and non-fatal) HR 1.04 (95% CI 0.87 to 1.24); 1 study; 14,641 participants; low-quality evidence, total stroke (fatal and non-fatal) HR 0.89 (95% CI 0.74 to 1.07); 1 study; 14,641 participants; low-quality evidence, CVD mortality HR 1.02 (95% 0.85 to 1.22); 1 study; 14,641 participants; very low-quality evidence, self-reported coronary artery bypass grafting (CABG)/percutaneous transluminal coronary angioplasty (PTCA) HR 0.96 (95% CI 0.86 to 1.07); 1 study; 14,641 participants; low-quality evidence, self-reported angina HR 0.93 (95% CI 0.84 to 1.03); 1 study; 14,641 participants; low-quality evidence.The evidence for the majority of primary outcomes was downgraded (low quality) because of indirectness and imprecision. For all-cause mortality and CVD mortality, the evidence was very low because more factors affected the directness of the evidence and because of inconsistency.Four studies did not state sources of funding, two studies declared non-commercial funding and two studies declared both commercial and non-commercial funding.

AUTHORS' CONCLUSIONS

Currently, there is no evidence to suggest that vitamin C supplementation reduces the risk of CVD in healthy participants and those at increased risk of CVD, but current evidence is limited to one trial of middle-aged and older male physicians from the USA. There is limited low- and very low-quality evidence currently on the effect of vitamin C supplementation and risk of CVD risk factors.

Headache meets neurology and psychiatry: a framework for diagnosis

This is a case of a very rare progressive disorder which presented with unusual neurological symptoms. Significant diagnostic challenges were experienced. A structured approach to each stage of the case demonstrates a framework to use when considering children with unusual neurological presentations.

Multiple Risk Factor Interventions for Primary Prevention of CVD in LMIC: A Cochrane Review

This study sought to determine the effectiveness of multiple risk factor interventions aimed at modifying major cardiovascular risk factors for the primary prevention of cardiovascular disease in low- and middle-income countries (LMIC). We searched electronic databases for randomized controlled trials of health promotion interventions to achieve behavior change. The pooled effect indicated a reduction in systolic blood pressure (-6.72 mm Hg; 95% confidence interval [CI]: -9.82 to -3.61; I² = 91%), diastolic blood pressure (-4.40 mm Hg; 95% CI: -6.47 to -2.34; I² = 92%), body mass index (-0.76 kg/m²; 95% CI: -1.29 to -0.22; I² = 80%), and waist circumference (-3.31 cm; 95% CI: -4.77 to -1.86; I² = 55%) in favor of multiple risk factor interventions. There is some evidence that multiple risk factor interventions may lower blood pressure levels and anthropometrics in populations in LMIC settings at high risk of hypertension and diabetes.

Pathogenic copy number variants and SCN1A mutations in patients with intellectual disability and childhood-onset epilepsy

Background

Copy number variants (CNVs) have been linked to neurodevelopmental disorders such as intellectual disability (ID), autism, epilepsy and psychiatric disease. There are few studies of CNVs in patients with both ID and epilepsy.

Methods

We evaluated the range of rare CNVs found in 80 Welsh patients with ID or developmental delay (DD), and childhood-onset epilepsy. We performed molecular cytogenetic testing by single nucleotide polymorphism array or microarray-based comparative genome hybridisation.

Results

8.8 % (7/80) of the patients had at least one rare CNVs that was considered to be pathogenic or likely pathogenic. The CNVs involved known disease genes (EHMT1, MBD5 and SCN1A) and imbalances in genomic regions associated with neurodevelopmental disorders (16p11.2, 16p13.11 and 2q13). Prompted by the observation of two deletions disrupting SCN1A we undertook further testing of this gene in selected patients. This led to the identification of four pathogenic SCN1A mutations in our cohort.

Conclusions

We identified five rare de novo deletions and confirmed the clinical utility of array analysis in patients with ID/DD and childhood-onset epilepsy. This report adds to our clinical understanding of these rare genomic disorders and highlights SCN1A mutations as a cause of ID and epilepsy, which can easily be overlooked in adults.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-016-0294-2) contains supplementary material, which is available to authorized users.

Dietary fibre for the primary prevention of cardiovascular disease

BACKGROUND

The prevention of cardiovascular disease (CVD) is a key public health priority. A number of dietary factors have been associated with modifying CVD risk factors. One such factor is dietary fibre which may have a beneficial association with CVD risk factors. There is a need to review the current evidence from randomised controlled trials (RCTs) in this area.

OBJECTIVES

The primary objective of this systematic review was to determine the effectiveness of dietary fibre for the primary prevention of CVD.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Ovid MEDLINE (1946 to January 2015), Ovid EMBASE (1947 to January 2015) and Science Citation Index Expanded (1970 to January 2015) as well as two clinical trial registers in January 2015. We also checked reference lists of relevant articles. No language restrictions were applied.

SELECTION CRITERIA

We selected RCTs that assessed the effects of dietary fibre compared with no intervention or a minimal intervention on CVD and related risk factors. Participants included adults who are at risk of CVD or those from the general population.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, extracted data and assessed risk of bias; a third author checked any differences. A different author checked analyses.

MAIN RESULTS

We included 23 RCTs (1513 participants randomised) examining the effect of dietary fibre. The risk of bias was unclear for most studies and studies had small sample sizes. Few studies had an intervention duration of longer than 12 weeks. There was a wide variety of fibre sources used, with little similarity between groups in the choice of intervention.None of the studies reported on mortality (total or cardiovascular) or cardiovascular events. Results on lipids suggest there is a significant beneficial effect of increased fibre on total cholesterol levels (17 trials (20 comparisons), 1067 participants randomised, mean difference -0.23 mmol/L, 95% CI -0.40 to -0.06), and LDL cholesterol levels (mean difference -0.14 mmol/L, 95% CI -0.22 to -0.06) but not on triglyceride levels (mean difference 0.00 mmol/L, 95% CI -0.04 to 0.05), and there was a very small but statistically significant decrease rather than increase in HDL levels with increased fibre intake (mean difference -0.03 mmol/L, 95% CI -0.06 to -0.01). Fewer studies (10 trials, 661 participants randomised) reported blood pressure outcomes where there is a significant effect of increased fibre consumption on diastolic blood pressure (mean difference -1.77 mmHg, 95% CI -2.61 to -0.92) whilst there is a reduction in systolic blood pressure with fibre but this does not reach statistical significance (mean difference -1.92 mmHg, 95% CI -4.02 to 0.19). There did not appear to be any subgroup effects by the nature of the type of intervention (fibre supplements or provision of foods/advice to increase fibre consumption) or the type of fibre (soluble/insoluble) although the number of studies contributing to each subgroup were small. All analyses need to be viewed with caution given the risks of bias observed for total cholesterol and the statistical heterogeneity observed for systolic blood pressure. Adverse events, where reported, appeared to mostly reflect mild to moderate gastrointestinal side-effects and these were generally reported more in the fibre intervention groups than the control groups.

AUTHORS' CONCLUSIONS

Studies were short term and therefore did not report on our primary outcomes, CVD clinical events. The pooled analyses for CVD risk factors suggest reductions in total cholesterol and LDL cholesterol with increased fibre intake, and reductions in diastolic blood pressure. There were no obvious effects of subgroup analyses by type of intervention or fibre type but the number of studies included in each of these analyses were small. Risk of bias was unclear in the majority of studies and high for some quality domains so results need to be interpreted cautiously. There is a need for longer term, well-conducted RCTs to determine the effects of fibre type (soluble versus insoluble) and administration (supplements versus foods) on CVD events and risk factors for the primary prevention of CVD.

Loss-of-function mutations in SCN4A cause severe foetal hypokinesia or 'classical' congenital myopathy

See Cannon (doi: 10.1093/brain/awv400 ) for a scientific commentary on this article.

Congenital myopathies are a clinically and genetically heterogeneous group of muscle disorders characterized by congenital or early-onset hypotonia and muscle weakness, and specific pathological features on muscle biopsy. The phenotype ranges from foetal akinesia resulting in in utero or neonatal mortality, to milder disorders that are not life-limiting. Over the past decade, more than 20 new congenital myopathy genes have been identified. Most encode proteins involved in muscle contraction; however, mutations in ion channel-encoding genes are increasingly being recognized as a cause of this group of disorders. SCN4A encodes the α-subunit of the skeletal muscle voltage-gated sodium channel (Na _v 1.4). This channel is essential for the generation and propagation of the muscle action potential crucial to muscle contraction. Dominant SCN4A gain-of-function mutations are a well-established cause of myotonia and periodic paralysis. Using whole exome sequencing, we identified homozygous or compound heterozygous SCN4A mutations in a cohort of 11 individuals from six unrelated kindreds with congenital myopathy. Affected members developed in utero - or neonatal-onset muscle weakness of variable severity. In seven cases, severe muscle weakness resulted in death during the third trimester or shortly after birth. The remaining four cases had marked congenital or neonatal-onset hypotonia and weakness associated with mild-to-moderate facial and neck weakness, significant neonatal-onset respiratory and swallowing difficulties and childhood-onset spinal deformities. All four surviving cohort members experienced clinical improvement in the first decade of life. Muscle biopsies showed myopathic features including fibre size variability, presence of fibrofatty tissue of varying severity, without specific structural abnormalities. Electrophysiology suggested a myopathic process, without myotonia. In vitro functional assessment in HEK293 cells of the impact of the identified SCN4A mutations showed loss-of-function of the mutant Na _v 1.4 channels. All, apart from one, of the mutations either caused fully non-functional channels, or resulted in a reduced channel activity. Each of the affected cases carried at least one full loss-of-function mutation. In five out of six families, a second loss-of-function mutation was present on the trans allele. These functional results provide convincing evidence for the pathogenicity of the identified mutations and suggest that different degrees of loss-of-function in mutant Na _v 1.4 channels are associated with attenuation of the skeletal muscle action potential amplitude to a level insufficient to support normal muscle function. The results demonstrate that recessive loss-of-function SCN4A mutations should be considered in patients with a congenital myopathy.

Omega 6 fatty acids for the primary prevention of cardiovascular disease

BACKGROUND

Omega 6 plays a vital role in many physiological functions but there is controversy concerning its effect on cardiovascular disease (CVD) risk. There is conflicting evidence whether increasing or decreasing omega 6 intake results in beneficial effects.

OBJECTIVES

The two primary objectives of this Cochrane review were to determine the effectiveness of:1. Increasing omega 6 (Linoleic acid (LA), Gamma-linolenic acid (GLA), Dihomo-gamma-linolenic acid (DGLA), Arachidonic acid (AA), or any combination) intake in place of saturated or monounsaturated fats or carbohydrates for the primary prevention of CVD.2. Decreasing omega 6 (LA, GLA, DGLA, AA, or any combination) intake in place of carbohydrates or protein (or both) for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases up to 23 September 2014: the Cochrane Central Register of Controlled Trials (CENTRAL) on the Cochrane Library (Issue 8 of 12, 2014); MEDLINE (Ovid) (1946 to September week 2, 2014); EMBASE Classic and EMBASE (Ovid) (1947 to September 2014); Web of Science Core Collection (Thomson Reuters) (1990 to September 2014); Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment Database, and Health Economics Evaluations Database on the Cochrane Library (Issue 3 of 4, 2014). We searched trial registers and reference lists of reviews for further studies. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of interventions stating an intention to increase or decrease omega 6 fatty acids, lasting at least six months, and including healthy adults or adults at high risk of CVD. The comparison group was given no advice, no supplementation, a placebo, a control diet, or continued with their usual diet. The outcomes of interest were CVD clinical events (all-cause mortality, cardiovascular mortality, non-fatal end points) and CVD risk factors (changes in blood pressure, changes in blood lipids, occurrence of type 2 diabetes). We excluded trials involving exercise or multifactorial interventions to avoid confounding.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted the data, and assessed the risk of bias in the included trials.

MAIN RESULTS

We included four RCTs (five papers) that randomised 660 participants. No ongoing trials were identified. All included trials had at least one domain with an unclear risk of bias. There were no RCTs of omega 6 intake reporting CVD clinical events. Three trials investigated the effect of increased omega 6 intake on lipid levels (total cholesterol, low density lipoprotein (LDL-cholesterol), and high density lipoprotein (HDL-cholesterol)), two trials reported triglycerides, and two trials reported blood pressure (diastolic and systolic blood pressure). Two trials, one with two relevant intervention arms, investigated the effect of decreased omega 6 intake on blood pressure parameters and lipid levels (total cholesterol, LDL-cholesterol, and HDL-cholesterol) and one trial reported triglycerides. Our analyses found no statistically significant effects of either increased or decreased omega 6 intake on CVD risk factors.Two studies were supported by funding from the UK Food Standards Agency and Medical Research Council. One study was supported by Lipid Nutrition, a commercial company in the Netherlands and the Dutch Ministry of Economic Affairs. The final study was supported by grants from the Finnish Food Research Foundation, Finnish Heart Research Foundation, Aarne and Aili Turnen Foundation, and the Research Council for Health, Academy of Finland.

AUTHORS' CONCLUSIONS

We found no studies examining the effects of either increased or decreased omega 6 on our primary outcome CVD clinical endpoints and insufficient evidence to show an effect of increased or decreased omega 6 intake on CVD risk factors such as blood lipids and blood pressure. Very few trials were identified with a relatively small number of participants randomised. There is a need for larger well conducted RCTs assessing cardiovascular events as well as cardiovascular risk factors.

Nut consumption for the primary prevention of cardiovascular disease

BACKGROUND

Nuts contain a number of nutritional attributes which may be cardioprotective. A number of epidemiological studies have shown that nut consumption may have a beneficial effect on people who have cardiovascular disease (CVD) risk factors. However, results from randomised controlled trials (RCTs) are less consistent.

OBJECTIVES

To determine the effectiveness of nut consumption for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science Core Collection, CINAHL, Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTA) and Health Economics Evaluations Database (HEED) up to 30 July 2015. We searched trial registers and reference lists of reviews for further studies. We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs of dietary advice to increase nut consumption or provision of nuts to increase consumption lasting at least three months and including healthy adults or adults at moderate and high risk of CVD. The comparison group was no intervention or minimal intervention. The outcomes of interest were CVD clinical events and CVD risk factors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias in included trials.

MAIN RESULTS

We included five trials (435 participants randomised) and one ongoing trial. One study is awaiting classification. All trials examined the provision of nuts to increase consumption rather than dietary advice. None of the included trials reported on the primary outcomes, CVD clinical events, but trials were small and short term. All five trials reported on CVD risk factors. Four of these trials provided data in a useable format for meta-analyses, but heterogeneity precluded meta-analysis for most of the analyses. Overall trials were judged to be at unclear risk of bias.There were variable and inconsistent effects of nut consumption on CVD risk factors (lipid levels and blood pressure). Three trials monitored adverse events. One trial reported an allergic reaction to nuts and three trials reported no significant weight gain with increased nut consumption. None of the included trials reported on other secondary outcomes, occurrence of type 2 diabetes as a major risk factor for CVD, health-related quality of life and costs.

AUTHORS' CONCLUSIONS

Currently there is a lack of evidence for the effects of nut consumption on CVD clinical events in primary prevention and very limited evidence for the effects on CVD risk factors. No conclusions can be drawn and further high quality longer term and adequately powered trials are needed to answer the review question.

Nut consumption for the primary prevention of cardiovascular disease

BACKGROUND

Nuts contain a number of nutritional attributes which may be cardioprotective. A number of epidemiological studies have shown that nut consumption may have a beneficial effect on people who have cardiovascular disease (CVD) risk factors. However, results from randomised controlled trials (RCTs) are less consistent.

OBJECTIVES

To determine the effectiveness of nut consumption for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science Core Collection, CINAHL, Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTA) and Health Economics Evaluations Database (HEED) up to 30 July 2015. We searched trial registers and reference lists of reviews for further studies. We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs of dietary advice to increase nut consumption or provision of nuts to increase consumption lasting at least three months and including healthy adults or adults at moderate and high risk of CVD. The comparison group was no intervention or minimal intervention. The outcomes of interest were CVD clinical events and CVD risk factors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias in included trials.

MAIN RESULTS

We included five trials (435 participants randomised) and one ongoing trial. One study is awaiting classification. All trials examined the provision of nuts to increase consumption rather than dietary advice. None of the included trials reported on the primary outcomes, CVD clinical events, but trials were small and short term. All five trials reported on CVD risk factors. Four of these trials provided data in a useable format for meta-analyses, but heterogeneity precluded meta-analysis for most of the analyses. Overall trials were judged to be at unclear risk of bias.There were variable and inconsistent effects of nut consumption on CVD risk factors (lipid levels and blood pressure). Three trials monitored adverse events. One trial reported an allergic reaction to nuts and three trials reported no significant weight gain with increased nut consumption. None of the included trials reported on other secondary outcomes, occurrence of type 2 diabetes as a major risk factor for CVD, health-related quality of life and costs.

AUTHORS' CONCLUSIONS

Currently there is a lack of evidence for the effects of nut consumption on CVD clinical events in primary prevention and very limited evidence for the effects on CVD risk factors. No conclusions can be drawn and further high quality longer term and adequately powered trials are needed to answer the review question.

Vitamin K for the primary prevention of cardiovascular disease

BACKGROUND

A deficiency in vitamin K has been associated with increased calcium deposition and coronary artery calcification, which may lead to cardiovascular disease.

OBJECTIVES

To determine the effectiveness of vitamin K supplementation as a single nutrient supplement for the primary prevention of cardiovascular disease.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 8 of 12, 2014); MEDLINE (Ovid, 1946 to September week 2 2014); EMBASE Classic + EMBASE (Ovid, 1947 to September 18 2014); Science Citation Index Expanded (SCI-EXPANDED) and Conference Proceedings Citation Index, Science (CPCI-S) (both 1990 to 17 September 2014) on Web of Science (Thomson Reuters); Database of Abstracts of Reviews of Effects (DARE); Health Technology Assessment Database and Health Economics Evaluations Database (Issue 3 of 4, 2014). We searched trial registers and reference lists of reviews for further studies. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials of vitamin K supplementation as a single nutrient supplement, lasting at least three months, and involving healthy adults or adults at high risk of cardiovascular disease. The comparison group was no intervention or placebo. The outcomes of interest were cardiovascular disease clinical events and cardiovascular disease risk factors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias.

MAIN RESULTS

We included only one small trial (60 participants randomised) which overall was judged to be at low risk of bias. The study examined two doses of menaquinone (vitamin K2) over 3 months in healthy participants aged 40 to 65 years. The primary focus of the trial was to examine the effects of menaquinone (subtype MK7) on different matrix Gla proteins (MGP - vitamin K dependent proteins in the vessel wall) at different doses, but the authors also reported blood pressure and lipid levels. The trial did not report on our primary outcomes (cardiovascular disease clinical events) as it was small, short term and conducted in healthy participants.In terms of cardiovascular disease risk factors, no effects were seen for vitamin K2 on blood pressure or lipid levels, although the trial was small and findings are limited. The trial did not report any of our other secondary outcomes.

AUTHORS' CONCLUSIONS

The very limited results of this review highlight the lack of evidence currently available to determine the effectiveness of vitamin K supplementation for the primary prevention of cardiovascular disease, and demonstrate the need for further high quality trials in this area.

Multiple risk factor interventions for primary prevention of cardiovascular disease in low- and middle-income countries

BACKGROUND

In many low- and middle-income countries (LMICs) morbidity and mortality associated with cardiovascular diseases (CVDs) have grown exponentially over recent years. It is estimated that about 80% of CVD deaths occur in LMICs. People in LMICs are more exposed to cardiovascular risk factors such as tobacco, and often do not have access to effective and equitable healthcare services (including early detection services). Evidence from high-income countries indicates that multiple risk factor intervention programmes do not result in reductions in CVD events. Given the increasing incidence of CVDs and lower CVD health awareness in LMICs it is possible that such programmes may have beneficial effects.

OBJECTIVES

To determine the effectiveness of multiple risk factor interventions (with or without pharmacological treatment) aimed at modifying major cardiovascular risk factors for the primary prevention of CVD in LMICs.

SEARCH METHODS

We searched (from inception to 27 June 2014) the Cochrane Library (CENTRAL, HTA, DARE, EED), MEDLINE, EMBASE, Global Health and three other databases on 27 June 2014. We also searched two clinical trial registers and conducted reference checking to identify additional studies. We applied no language limits.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of health promotion interventions to achieve behaviour change (i.e. smoking cessation, dietary advice, increasing activity levels) with or without pharmacological treatments, which aim to alter more than one cardiovascular risk factor (i.e. diet, reduce blood pressure, smoking, total blood cholesterol or increase physical activity) of at least six months duration of follow-up conducted in LMICs.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and risk of bias, and extracted data. We combined dichotomous data using risk ratios (RRs) and continuous data using mean differences (MDs), and presented all results with a 95% confidence interval (CI). The primary outcome was combined fatal and non-fatal cardiovascular disease events.

MAIN RESULTS

Thirteen trials met the inclusion criteria and are included in the review. All studies had at least one domain with unclear risk of bias. Some studies were at high risk of bias for random sequence generation (two trials), allocation concealment (two trials), blinding of outcome assessors (one trial) and incomplete outcome data (one trial). Duration and content of multiple risk factor interventions varied across the trials. Two trials recruited healthy participants and the other 11 trials recruited people with varying risks of CVD, such as participants with known hypertension and type 2 diabetes. Only one study reported CVD outcomes and multiple risk factor interventions did not reduce the incidence of cardiovascular events (RR 0.57, 95% CI 0.11 to 3.07, 232 participants, low-quality evidence); the result is imprecise (a wide confidence interval and small sample size) and makes it difficult to draw a reliable conclusion. None of the included trials reported all-cause mortality. The pooled effect indicated a reduction in systolic blood pressure (MD -6.72 mmHg, 95% CI -9.82 to -3.61, I² = 91%, 4868 participants, low-quality evidence), diastolic blood pressure (MD -4.40 mmHg, 95% CI -6.47 to -2.34, I² = 92%, 4701 participants, low-quality evidence), body mass index (MD -0.76 kg/m², 95% CI -1.29 to -0.22, I² = 80%, 2984 participants, low-quality evidence) and waist circumference (MD -3.31, 95% CI -4.77 to -1.86, I² = 55%, 393 participants, moderate-quality evidence) in favour of multiple risk factor interventions, but there was substantial heterogeneity. There was insufficient evidence to determine the effect of these interventions on consumption of fruit or vegetables, smoking cessation, glycated haemoglobin, fasting blood sugar, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol and total cholesterol. None of the included trials reported on adverse events.

AUTHORS' CONCLUSIONS

Due to the limited evidence currently available, we can draw no conclusions as to the effectiveness of multiple risk factor interventions on combined CVD events and mortality. There is some evidence that multiple risk factor interventions may lower blood pressure levels, body mass index and waist circumference in populations in LMIC settings at high risk of hypertension and diabetes. There was considerable heterogeneity between the trials, the trials were small, and at some risk of bias. Larger studies with longer follow-up periods are required to confirm whether multiple risk factor interventions lead to reduced CVD events and mortality in LMIC settings.

Qigong for the primary prevention of cardiovascular disease

BACKGROUND

Two major determinants of cardiovascular disease (CVD) are a sedentary lifestyle and stress. Qigong involves physical exercise, mind regulation and breathing control to restore the flow of Qi (a pivotal life energy). As it is thought to help reduce stress and involves exercise, qigong may be an effective strategy for the primary prevention of CVD.

OBJECTIVES

To determine the effectiveness of qigong for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (November 2014, Issue 10 of 12); MEDLINE (Ovid) (1946 to 2014 October week 4); EMBASE Classic + EMBASE (Ovid) (1947 to 2014 November 4); Web of Science Core Collection (1970 to 31 October 2014); Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database and Health Economics Evaluations Database (November 2014, Issue 4 of 4). We searched several Asian databases (inception to July 2013) and the Allied and Complementary Medicine Database (AMED) (inception to December 2013), as well as trial registers and reference lists of reviews and articles; we also approached experts in the field and applied no language restrictions in our search.

SELECTION CRITERIA

Randomised controlled trials lasting at least three months involving healthy adults or those at high risk of CVD. Trials examined any type of qigong, and comparison groups provided no intervention or minimal intervention. Outcomes of interest included clinical CVD events and major CVD risk factors. We did not include trials that involved multi-factorial lifestyle interventions or weight loss.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion. Two review authors extracted data from included studies and assessed the risk of bias.

MAIN RESULTS

We identified 11 completed trials (1369 participants) and one ongoing trial. Trials were heterogeneous in participants recruited, qigong duration and length of follow-up periods. We were unable to ascertain the risk of bias in nine trials published in Chinese, as insufficient methodological details were reported and we were unable to contact the study authors to clarify this.We performed no meta-analyses, as trials were small and were at significant risk of bias. Clinical events were detailed in subsequent reports of two trials when statistically significant effects of qigong were seen for all-cause mortality, stroke mortality and stroke incidence at 20 to 30 years after completion of the trials. However, these trials were designed to examine outcomes in the short term, and it is not clear whether qigong was practised during extended periods of follow-up; therefore effects cannot be attributed to the intervention. None of the included studies reported other non-fatal CVD events.Six trials provided data that could be used to examine the effects of qigong on blood pressure. Reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) were seen in three and two trials, respectively. Three trials examined the effects of qigong on blood lipids when favourable effects were seen in one trial for total cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides, and two trials showed favourable effects on high-density lipoprotein (HDL) cholesterol. The only trial considered at low risk of selection and detection bias did not demonstrate statistically significant effects on CVD risk factors with qigong, but this study was small and was underpowered. None of the included studies reported incidence of type 2 diabetes (T2D), adverse events, quality of life or costs.

AUTHORS' CONCLUSIONS

Currently, very limited evidence is available on the effectiveness of qigong for the primary prevention of CVD. Most of the trials included in this review are likely to be at high risk of bias, so we have very low confidence in the validity of the results. Publication of the ongoing trial will add to the limited evidence base, but further trials of high methodological quality with sufficient sample size and follow-up are needed to be incorporated in an update of this review before the effectiveness of qigong for CVD prevention can be established.

Hormone therapy for preventing cardiovascular disease in post-menopausal women

BACKGROUND

Evidence from systematic reviews of observational studies suggests that hormone therapy may have beneficial effects in reducing the incidence of cardiovascular disease events in post-menopausal women, however the results of randomised controlled trials (RCTs) have had mixed results. This is an updated version of a Cochrane review published in 2013.

OBJECTIVES

To assess the effects of hormone therapy for the prevention of cardiovascular disease in post-menopausal women, and whether there are differential effects between use in primary or secondary prevention. Secondary aims were to undertake exploratory analyses to (i) assess the impact of time since menopause that treatment was commenced (≥ 10 years versus < 10 years), and where these data were not available, use age of trial participants at baseline as a proxy (≥ 60 years of age versus < 60 years of age); and (ii) assess the effects of length of time on treatment.

SEARCH METHODS

We searched the following databases on 25 February 2014: Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE and LILACS. We also searched research and trials registers, and conducted reference checking of relevant studies and related systematic reviews to identify additional studies.

SELECTION CRITERIA

RCTs of women comparing orally administered hormone therapy with placebo or a no treatment control, with a minimum of six months follow-up.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. We calculated risk ratios (RRs) with 95% confidence intervals (CIs) for each outcome. We combined results using random effects meta-analyses, and undertook further analyses to assess the effects of treatment as primary or secondary prevention, and whether treatment was commenced more than or less than 10 years after menopause.

MAIN RESULTS

We identified six new trials through this update. Therefore the review includes 19 trials with a total of 40,410 post-menopausal women. On the whole, study quality was good and generally at low risk of bias; the findings are dominated by the three largest trials. We found high quality evidence that hormone therapy in both primary and secondary prevention conferred no protective effects for all-cause mortality, cardiovascular death, non-fatal myocardial infarction, angina, or revascularisation. However, there was an increased risk of stroke in those in the hormone therapy arm for combined primary and secondary prevention (RR 1.24, 95% CI 1.10 to 1.41). Venous thromboembolic events were increased (RR 1.92, 95% CI 1.36 to 2.69), as were pulmonary emboli (RR 1.81, 95% CI 1.32 to 2.48) on hormone therapy relative to placebo.The absolute risk increase for stroke was 6 per 1000 women (number needed to treat for an additional harmful outcome (NNTH) = 165; mean length of follow-up: 4.21 years (range: 2.0 to 7.1)); for venous thromboembolism 8 per 1000 women (NNTH = 118; mean length of follow-up: 5.95 years (range: 1.0 to 7.1)); and for pulmonary embolism 4 per 1000 (NNTH = 242; mean length of follow-up: 3.13 years (range: 1.0 to 7.1)).We performed subgroup analyses according to when treatment was started in relation to the menopause. Those who started hormone therapy less than 10 years after the menopause had lower mortality (RR 0.70, 95% CI 0.52 to 0.95, moderate quality evidence) and coronary heart disease (composite of death from cardiovascular causes and non-fatal myocardial infarction) (RR 0.52, 95% CI 0.29 to 0.96; moderate quality evidence), though they were still at increased risk of venous thromboembolism (RR 1.74, 95% CI 1.11 to 2.73, high quality evidence) compared to placebo or no treatment. There was no strong evidence of effect on risk of stroke in this group. In those who started treatment more than 10 years after the menopause there was high quality evidence that it had little effect on death or coronary heart disease between groups but there was an increased risk of stroke (RR 1.21, 95% CI 1.06 to 1.38, high quality evidence) and venous thromboembolism (RR 1.96, 95% CI 1.37 to 2.80, high quality evidence).

AUTHORS' CONCLUSIONS

Our review findings provide strong evidence that treatment with hormone therapy in post-menopausal women overall, for either primary or secondary prevention of cardiovascular disease events has little if any benefit and causes an increase in the risk of stroke and venous thromboembolic events.

Yoga for the primary prevention of cardiovascular disease

BACKGROUND

A sedentary lifestyle and stress are major risk factors for cardiovascular disease (CVD). Since yoga involves exercise and is thought to help in stress reduction it may be an effective strategy in the primary prevention of CVD.

OBJECTIVES

To determine the effect of any type of yoga on the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 11) in The Cochrane Library; MEDLINE (Ovid) (1946 to November Week 3 2013); EMBASE Classic + EMBASE (Ovid) (1947 to 2013 Week 48); Web of Science (Thomson Reuters) (1970 to 4 December 2013); Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database and Health Economics Evaluations Database (Issue 4 of 4, 2013) in The Cochrane Library. We also searched a number of Asian databases and the Allied and Complementary Medicine Database (AMED) (inception to December 2012). We searched trial registers and reference lists of reviews and articles, and approached experts in the field. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials lasting at least three months involving healthy adults or those at high risk of CVD. Trials examined any type of yoga and the comparison group was no intervention or minimal intervention. Outcomes of interest were clinical CVD events and major CVD risk factors. We did not include any trials that involved multifactorial lifestyle interventions or weight loss.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion, extracted data and assessed the risk of bias.

MAIN RESULTS

We identified 11 trials (800 participants) and two ongoing studies. Style and duration of yoga differed between trials. Half of the participants recruited to the studies were at high risk of CVD. Most of studies were at risk of performance bias, with inadequate details reported in many of them to judge the risk of selection bias.No study reported cardiovascular mortality, all-cause mortality or non-fatal events, and most studies were small and short-term. There was substantial heterogeneity between studies making it impossible to combine studies statistically for systolic blood pressure and total cholesterol. Yoga was found to produce reductions in diastolic blood pressure (mean difference (MD) -2.90 mmHg, 95% confidence interval (CI) -4.52 to -1.28), which was stable on sensitivity analysis, triglycerides (MD -0.27 mmol/l, 95% CI -0.44 to -0.11) and high-density lipoprotein (HDL) cholesterol (MD 0.08 mmol/l, 95% CI 0.02 to 0.14). However, the contributing studies were small, short-term and at unclear or high risk of bias. There was no clear evidence of a difference between groups for low-density lipoprotein (LDL) cholesterol (MD -0.09 mmol/l, 95% CI -0.48 to 0.30), although there was moderate statistical heterogeneity. Adverse events, occurrence of type 2 diabetes and costs were not reported in any of the included studies. Quality of life was measured in three trials but the results were inconclusive.

AUTHORS' CONCLUSIONS

The limited evidence comes from small, short-term, low-quality studies. There is some evidence that yoga has favourable effects on diastolic blood pressure, HDL cholesterol and triglycerides, and uncertain effects on LDL cholesterol. These results should be considered as exploratory and interpreted with caution.

Tai chi for primary prevention of cardiovascular disease

BACKGROUND

Stress and a sedentary lifestyle are major determinants of cardiovascular disease (CVD). As tai chi involves exercise and can help in stress reduction, it may be effective in the primary prevention of CVD.

OBJECTIVES

To determine the effectiveness of tai chi for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 11, 2013); MEDLINE (Ovid) (1946 to November week 3, 2013); EMBASE Classic + EMBASE (Ovid) (1947 to 6 December 2013); Web of Science (Thomson Reuters) (1970 to 6 December 2013); PsycINFO (Ovid) (1806 to December week 1, 2013); Database of Abstracts of Reviews of Effects (DARE); Health Technology Assessment Database and Health Economics Evaluations Database (Issue 4, 2013). We also searched the Allied and complementary Medicine Database (AMED) and OpenGrey (inception to October 2012) and several Asian databases. We searched trial registers and reference lists of reviews for further studies. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of tai chi lasting at least three months involving healthy adults or adults at high risk of CVD. The comparison group was no intervention or minimal intervention. The outcomes of interest were CVD clinical events and CVD risk factors. We excluded trials involving multifactorial lifestyle interventions or focusing on weight loss to avoid confounding.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias.

MAIN RESULTS

We identified 13 small trials (1520 participants randomised) and three ongoing trials. All studies had at least one domain with unclear risk of bias, and some studies were at high risk of bias for allocation concealment (one study) and selective reporting (two studies). Duration and style of tai chi differed between trials. Seven studies recruited 903 healthy participants, the other studies recruited people with borderline hypertension or hypertension, elderly people at high risk of falling, and people with hypertension with liver and kidney yin deficiency syndrome.No studies reported on cardiovascular mortality, all-cause mortality or non-fatal events as most studies were short term (all studies had follow-up of one year or less). There was also considerable heterogeneity between studies, which meant that it was not possible to combine studies statistically for cardiovascular risk (I(2) statistic for systolic blood pressure (SBP) was 96%, for diastolic blood pressure (DBP) 96%, for total cholesterol 96%, low-density lipoprotein-cholesterol (LDL-C) 95%, high-density lipoprotein-cholesterol (HDL-C) 98%, triglycerides 75%). Nine trials measured blood pressure, six individual trials found reductions in SBP (reductions ranged from -22.0 mmHg (95% confidence interval (CI) -26.3 to -17.7) to -11.5 mmHg (95% CI -21.5 to -1.46)), two trials found no clear evidence of a difference (however, CIs were wide and an increase or decrease in SBP cannot be ruled out), and one trial found an increase in SBP with tai chi (increase 5.2 mmHg, 95% CI 3.73 to 6.67). A similar pattern was seen for DBP: three trials found a reduction in DBP (reductions ranged from -12.2 mmHg (95% CI -15.8 to -8.7) to -4.43 mmHg (95% CI -7.14 to -1.72)) and three trials found no clear evidence of a difference, however again with wide CIs. Three trials reported lipid levels and two found reductions in total cholesterol, LDL-C and triglycerides (total cholesterol reductions ranged from -1.30 mmol/L (95% CI -1.57 to -1.03) to -0.50 mmol/L (95% CI -0.74 to -0.26): LDL-C reductions ranged from -0.76 mmol/L (95% CI -0.93 to -0.59) to -0.59 mmol/L (95% CI -0.80 to -0.38): triglyceride reductions ranged from -0.46 mmol/L (95% CI -0.62 to -0.30) to -0.37 mmol/L (95% CI -0.67 to-0.07)) and increased HDL-C with the intervention (HDL-C increases ranged from 0.61 mmol/L (95% CI 0.51 to 0.71) to 0.16 mmol/L (95% CI 0.02 to 0.30)), while the third study found no clear evidence of a difference between groups on lipid levels. Quality of life was measured in one trial: tai chi improved quality of life at three months. None of the included trials reported on adverse events, costs or occurrence of type 2 diabetes.

AUTHORS' CONCLUSIONS

There are currently no long-term trials examining tai chi for the primary prevention of CVD. Due to the limited evidence available currently no conclusions can be drawn as to the effectiveness of tai chi on CVD risk factors. There was some suggestion of beneficial effects of tai chi on CVD risk factors but this was not consistent across all studies. There was considerable heterogeneity between the studies included in this review and studies were small and at some risk of bias. Results of the ongoing trials will add to the evidence base but additional longer-term, high-quality trials are needed.

Transcendental meditation for the primary prevention of cardiovascular disease

BACKGROUND

A major determinant in cardiovascular disease (CVD) is stress. As transcendental meditation (TM) is thought to help in lowering negative stress indicators, it may be a beneficial strategy for the primary prevention of CVD.

OBJECTIVES

To determine the effectiveness of TM for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 10); MEDLINE (Ovid) (1946 to week three November 2013); EMBASE Classic and EMBASE (Ovid) (1947 to week 48 2013); ISI Web of Science (1970 to 28 November 2013); and Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment Database and Health Economics Evaluations Database (November 2013). We also searched the Allied and complementary Medicine Database (AMED) (inception to January 2014) and IndMed (inception to January 2014). We handsearched trial registers and reference lists of reviews and articles and contacted experts in the field. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of at least three months' duration involving healthy adults or adults at high risk of CVD. Trials examined TM only and the comparison group was no intervention or minimal intervention. We excluded trials that involved multi-factorial interventions. Outcomes of interest were clinical CVD events (cardiovascular mortality, all-cause mortality and non-fatal events) and major CVD risk factors (e.g. blood pressure and blood lipids, occurrence of type 2 diabetes, quality of life, adverse events and costs).

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion, extracted data and assessed the risk of bias.

MAIN RESULTS

We identified four trials (four papers) (430 participants) for inclusion in this review. We identified no ongoing studies. The included trials were small, short term (three months) and at risk of bias. In all studies, TM was practised for 15 to 20 minutes twice a day.None of the included studies reported all-cause mortality, cardiovascular mortality or non-fatal endpoints as trials were short term, but one study reported survival rate three years after the trial was completed. In view of the considerable statistical heterogeneity between the results of the studies for the only outcomes reported, systolic blood pressure (I(2) = 72%) and diastolic blood pressure (I(2) = 66%), we decided not to undertake a meta-analysis. None of the four trials reported blood lipids, occurrence of type 2 diabetes, adverse events, costs or quality of life.

AUTHORS' CONCLUSIONS

Currently, there are few trials with limited outcomes examining the effectiveness of TM for the primary prevention of CVD. Due to the limited evidence to date, we could draw no conclusions as to the effectiveness of TM for the primary prevention of CVD. There was considerable heterogeneity between trials and the included studies were small, short term and at overall serious risk of bias. More and larger long-term, high-quality trials are needed.

Co-enzyme Q10 supplementation for the primary prevention of cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) remains the number one cause of death and disability worldwide and public health interventions focus on modifiable risk factors, such as diet. Coenzyme Q10 (CoQ10) is an antioxidant that is naturally synthesised by the body and can also be taken as a dietary supplement. Studies have shown that a CoQ10 deficiency is associated with cardiovascular disease.

OBJECTIVES

To determine the effects of coenzyme Q10 supplementation as a single ingredient for the primary prevention of CVD.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2013, Issue 11); MEDLINE (Ovid, 1946 to November week 3 2013); EMBASE (Ovid, 1947 to 27 November 2013) and other relevant resources on 2 December 2013. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) lasting at least three months involving healthy adults or those at high risk of CVD but without a diagnosis of CVD. Trials investigated the supplementation of CoQ10 alone as a single supplement. The comparison group was no intervention or placebo. The outcomes of interest were CVD clinical events and major CVD risk factors, adverse effects and costs. We excluded any trials involving multifactorial lifestyle interventions to avoid confounding.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion, abstracted data and assessed the risk of bias.We contacted authors for additional information where necessary.

MAIN RESULTS

We identified six RCTs with a total of 218 participants randomised, one trial awaiting classification and five ongoing trials. All trials were conducted in participants at high risk of CVD, two trials examined CoQ10 supplementation alone and four examined CoQ10 supplementation in patients on statin therapy; we analysed these separately. All six trials were small-scale, recruiting between 20 and 52 participants; one trial was at high risk of bias for incomplete outcome data and one for selective reporting; all studies were unclear in the method of allocation and therefore for selection bias. The dose of CoQ10 varied between 100 mg/day and 200 mg/day and the duration of the interventions was similar at around three months.No studies reported mortality or non-fatal cardiovascular events. None of the included studies provided data on adverse events.Two trials examined the effect of CoQ10 on blood pressure. For systolic blood pressure we did not perform a meta-analysis due to significant heterogeneity. In one trial CoQ10 supplementation had no effect on systolic blood pressure (mean difference (MD) -1.90 mmHg, 95% confidence interval (CI) -13.17 to 9.37, 51 patients randomised). In the other trial there was a statistically significant reduction in systolic blood pressure (MD -15.00 mmHg, 95% CI -19.06 to -10.94, 20 patients randomised). For diastolic blood pressure we performed a random-effects meta-analysis, which showed no evidence of effect of CoQ10 supplementation when these two small trials were pooled (MD -1.62 mmHg, 95% CI -5.2 to 1.96).One trial (51 patients randomised) looked at the effect of CoQ10 on lipid levels. The trial showed no evidence of effect of CoQ10 supplementation on total cholesterol (MD 0.30 mmol/L, 95% CI -0.10 to 0.70), high-density lipoprotein (HDL)-cholesterol (MD 0.02 mmol/L, 95% CI -0.13 to 0.17) or triglycerides (MD 0.05 mmol/L, 95% CI -0.42 to 0.52).Of the four trials that investigated CoQ10 supplementation in patients on statin therapy, three of them showed that simultaneous administration of CoQ10 did not significantly influence lipid levels or systolic blood pressure levels between the two groups. The fourth trial showed a significant increase in the change in total and low-density lipoprotein (LDL)-cholesterol at three months across the four arms of the trial (α-tocopherol, CoQ10, CoQ10 + α-tocopherol and placebo), however the way in which the data were presented meant that we were unable to determine if there was any significant difference between the CoQ10 only and placebo arms. In contrast, there was no significant difference in the change in HDL-cholesterol and triglycerides after three months between the four arms of the trial.

AUTHORS' CONCLUSIONS

There are very few studies to date examining CoQ10 for the primary prevention of CVD. The results from the ongoing studies will add to the evidence base. Due to the small number of underpowered trials contributing to the analyses, the results presented should be treated with caution and further high quality trials with longer-term follow-up are needed to determine the effects on cardiovascular events.