The long-term impact of vaginal surgical mesh devices on pain clinic and psychological service referrals, anti-inflammatory testing and pelvic scans in UK primary care: A cohort study with the Clinical Practice Research Datalink

OBJECTIVE

To examine long-term complications in women with stress urinary incontinence (SUI) and pelvic organ prolapse (POP), with and without surgical mesh implants.

DESIGN

Longitudinal open cohort study from 1 April 2006 (or 1 April 2012) to 30 November 2018.

SETTING

The Clinical Practice Research Datalink (CPRD) Gold database, which is linked to Hospital Episodes Statistics (HES) inpatient data, the HES Diagnostic Imaging Dataset (DID), Office for National Statistics mortality data and Index of Multiple Deprivation socio-economic status data.

SAMPLE

Women aged ≥18 years with a diagnostic SUI/POP Read code.

METHODS

Rates are estimated using negative binomial regression.

MAIN OUTCOME MEASURES

Rates of referrals for: psychological and pain services; urinalysis, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) testing; and pelvic ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) scans.

RESULTS

A cohort of 220 544 women were eligible for inclusion; 74% (n = 162 687) had SUI, 37% (n = 82 123) had POP and 11% (n = 24 266) had both. Rates of psychological referrals and CT scans were lower in women with SUI mesh surgery, but this was offset by higher rates of CRP testing in women with SUI or POP mesh, MRI scans in women with SUI mesh, and urinalysis testing and referrals to pain clinics for women with POP mesh.

CONCLUSIONS

Our results suggest a higher burden of morbidity in women with SUI/POP mesh surgery, and that these women may require ongoing follow-up in the primary care setting.

The impact of vaginal surgical mesh devices on consultation rates by type and health care provider in UK primary care: A cohort study in the Clinical Practice Research Datalink

OBJECTIVES

To examine consultation rates by type of consultation and health care provider in women with stress urinary incontinence (SUI) and/or pelvic organ prolapse (POP), with and without surgical mesh implants.

STUDY DESIGN

Longitudinal open cohort study from April 2006 to November 2018 in the Clinical Practice Research Datalink (CPRD).

MAIN OUTCOME MEASURES

Rates of consultations with general practitioners (GPs), nurses, other clinicians and administrators by consultation type (face-to-face, telephone or administrative), and types of administrative consultations, estimated using negative binomial regression.

RESULTS

Of 220,544 women eligible for inclusion, 74 % (n = 162,687) had SUI, 37 % (n = 82,123) had POP, and 11 % (n = 24,266) had both. Face-to-face consultation rates were stable over time, at about 9 per year. Administrative consultations with GPs and administrators increased between 2006 and 2018, but averaged 31 per year. After adjustment, for both SUI and POP mesh surgery, there were lower rates of face-to-face consultations with GPs, higher rates of face-to-face consultations with other clinicians, higher rates of telephone consultations with GPs and other clinicians, and higher rates of administrative consultations with GPs, nurses and administrators. The higher rate of consultations with GPs coded as administrative consisted of results recording and administrative codes, and the higher rates of consultations with administrators were coded as repeat issue, other, administration and third-party consultations.

CONCLUSIONS

Caring for women with mesh places a higher administrative burden on GPs and administrators. There may be potential to reduce this workload through a more streamlined care pathway.

Association between disability status and health care utilisation for common childhood illnesses in 10 countries in sub-Saharan Africa: a cross-sectional study in the Multiple Indicator Cluster Survey

BACKGROUND

Approximately 70 million children in sub-Saharan Africa (SSA) are disabled, yet little is known about the prevalence of and care-seeking patterns for common childhood illnesses, such as acute respiratory infection (ARI), diarrhoea, and fever.

METHODS

Data were from 10 SSA countries with data available from 2017 to 2020 in the UNICEF-supported Multiple Indicator Cluster Survey (MICS) online repository. Children aged 2-4 years who completed the child functioning module were included. Using logistic regression, we examined the association between disability and ARI, diarrhoea and fever in the past two weeks and care-seeking behaviour for these illnesses. Using multinomial logistic regression, we examined the association between disability and the type of health care providers from which caregivers sought care.

FINDINGS

There were 51,901 children included. Overall, there were small absolute differences in illnesses between disabled and non-disabled children. However, there was evidence disabled children had a greater odds of ARI (aOR = 1.33, 95% C.I 1.16-1.52), diarrhoea (aOR = 1.27, 95% C.I. 1.12-1.44), and fever (aOR = 1.19 95% CI 1.06-1.35) compared to non-disabled children. There was no evidence that caregivers of disabled children had a greater odds of seeking care for ARI (aOR = 0.90, 95% C.I 0.69-1.19), diarrhoea (aOR = 1.06, 95% C.I. 0.84-1.34), and fever (aOR = 1.07, 95% C.I 0.88-1.30) compared to caregivers of non-disabled children. Caregivers of disabled children had a higher odds of seeking care from a trained health worker for ARI (aOR = 1.76, 95% C.I. 1.25-2.47) and fever (aOR = 1.49, 95% C.I. 1.03-2.14) or non-health professional (aOR = 1.89, 95% C.I. 1.19-2.98) for ARI than from an unspecified health facility worker compared to caregivers of non-disabled children, but no associations were not seen for diarrhoea.

INTERPRETATION

While the data showed relatively small absolute differences, disability was associated with ARI, diarrhoea and fever and caregivers of disabled children sought care from trained health workers for ARI and fever more than non-disabled children. The overall small absolute differences show closing gaps in illness and access to care may be possible, but highlights that more research on illness severity, care quality, and outcomes should be conducted to further assess health inequities for disabled children.

FUNDING

SR receives funding from the Rhodes Trust.

Improved responsiveness to change in joint space width over 24-month follow-up: comparison of 3D JSW on weight-bearing CT vs 2D JSW on radiographs in the MOST study

OBJECTIVE

Radiographic joint space width (JSW) has been a standard for measuring knee osteoarthritis (OA) structural change. Limitations in the responsiveness of this approach might be overcome by instead measuring 3D JSW on weight-bearing CT (WBCT). This study compared the responsiveness of 3D JSW measurements using WBCT with the responsiveness of radiographic 2D JSW.

DESIGN

Standing, fixed-flexion knee radiographs (XR) and WBCT were acquired ancillary to the 144- and 168-month Multicenter Osteoarthritis Study visits. Tibiofemoral JSW was measured on both XR and WBCT. Responsiveness to change was defined by the standardized response mean (SRM) for change in JSW (1) at predetermined mediolateral locations (JSWx) on both modalities and (2) in the following subregions measured on WBCT images: central medial and lateral femur (CMF/CLF) and tibia (CMT/CLT), and anterior and posterior tibia (AMT/ALT, PMT/MLT).

RESULTS

Baseline and 24-month follow-up JSWx measurements were completed for 265 participants (58.1% women). Responsiveness of 3D JSWx for medial tibiofemoral compartment on coronal WBCT (SRM range: -0.18, -0.24) exceeded that for 2D JSWx (-0.10, -0.16). Responsiveness of 3D JSW subregional mean (-0.06, -0.36) and maximal (-1.14, -1.75) CMF and CMT and maximal CLF/CLT 3D JSW changes were statistically significantly greater in comparison with respective medial and lateral 2D JSWx (P ≤ 0.002).

CONCLUSIONS

Subregional 3D JSW on WBCT is substantially more responsive to 24-month changes in tibiofemoral joint structure compared to radiographic measurements. Use of subregional 3D JSW on WBCT could enable improved detection of OA structural progression over a 24-month duration in comparison with measurements made on XR.

The Long-Term Impact of Vaginal Surgical Mesh Devices in UK Primary Care: A Cohort Study in the Clinical Practice Research Datalink

PURPOSE

Stress urinary incontinence (SUI) and pelvic organ prolapse (POP) may be treated with surgical mesh devices; evidence of their long-term complications is lacking.

PATIENTS AND METHODS

Rates of diagnoses of depression, anxiety or self-harm (composite measure) and sexual dysfunction, and rates of prescriptions for antibiotics and opioids were estimated in women with and without mesh surgery, with a diagnostic SUI/POP code, registered in the Clinical Practice Research Datalink (CPRD) gold database.

RESULTS

There were 220,544 women eligible for inclusion; 74% (n = 162,687) had SUI, 37% (n = 82,123) had POP, and 11% (n = 24,266) had both. Women undergoing mesh surgery for SUI or POP had about 1.1 times higher rates of antibiotic use. Women with no previous history of the outcome, who underwent mesh surgery had 2.43 (95% CI 2.19-2.70) and 1.47 (95% CI 1.19-1.81) times higher rates of depression, anxiety, or self-harm, 1.88 (95% CI 1.50-2.36) and 1.64 (95% CI 1.02-2.63) times higher rates of sexual dysfunction and 1.40 (95% CI 1.26-1.56) and 1.23 (95% CI 1.01-1.49) times higher opioid use for SUI and POP, respectively. Women with a history of depression, anxiety and self-harm had 0.3 times lower rates of these outcomes with SUI or POP mesh surgery (HR for SUI 0.70 (95% CI 0.67-0.73), HR for POP 0.72 (95% CI 0.65-0.79)). Women with a history of opioid use who had POP mesh surgery had about 0.09 times lower rates (HR 0.91 (95% CI 0.86-0.96)) of prescriptions. Negative control outcome analyses showed no evidence of an association between asthma consultations and mesh surgery in women with POP, but the rate was 0.09 times lower (HR 0.91 (95% CI 0.87-0.94)) in women with SUI mesh surgery, suggesting that study results are subject to some residual confounding.

CONCLUSION

Mesh surgery was associated with poor mental and sexual health outcomes, alongside increased opioid and antibiotic use, in women with no history of these outcomes and improved mental health, and lower opioid use, in women with a previous history of these outcomes. Although our results suggest an influence of residual confounding, careful consideration of the benefits and risk of mesh surgery for women with SUI or POP on an individual basis is required.

Blood eosinophils to guide inhaled maintenance therapy in a primary care COPD population

Blood eosinophils are a potentially useful biomarker for guiding inhaled corticosteroid (ICS) treatment decisions in COPD. We investigated whether existing blood eosinophil counts predict benefit from initiation of ICS compared to bronchodilator therapy.

We used routinely collected data from UK primary care in the Clinical Practice Research Datalink. Participants were aged ≥40 years with COPD, were ICS-naïve and starting a new inhaled maintenance medication (intervention group: ICS; comparator group: long-acting bronchodilator, non-ICS). Primary outcome was time to first exacerbation, compared between ICS and non-ICS groups, stratified by blood eosinophils (“high” ≥150 cells·µL−1 and “low” <150 cells·µL−1).

Out of 9475 eligible patients, 53.9% initiated ICS and 46.1% non-ICS treatment with no difference in eosinophils between treatment groups (p=0.71). Exacerbation risk was higher in patients prescribed ICS than those prescribed non-ICS treatment, but with a lower risk in those with high eosinophils (hazard ratio (HR) 1.04, 95% CI 0.98–1.10) than low eosinophils (HR 1.19, 95% CI 1.09–1.31) (p-value for interaction 0.01). Risk of pneumonia hospitalisation with ICS was greatest in those with low eosinophils (HR 1.26, 95% CI 1.05–1.50; p-value for interaction 0.04). Results were similar whether the most recent blood eosinophil count or the mean of blood eosinophil counts was used.

In a primary care population, the most recent blood eosinophil count could be used to guide initiation of ICS in COPD patients. We suggest that ICS should be considered in those with higher eosinophils and avoided in those with lower eosinophils (<150 cells·µL−1).

A novel non-viral delivery method that enables efficient engineering of primary human T cells for ex vivo cell therapy applications

Background aims

Next-generation immune cell therapy products will require complex modifications using engineering technologies that can maintain high levels of cell functionality. Non-viral engineering methods have the potential to address limitations associated with viral vectors. However, while electroporation is the most widely used non-viral modality, concerns about its effects on cell functionality have led to the exploration of alternative approaches. Here the authors have examined the suitability of the Solupore non-viral delivery system for engineering primary human T cells for cell therapy applications.

Methods

The Solupore system was used to deliver messenger RNA (mRNA) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) guide RNA ribonucleoprotein (RNP) cargos to T cells, and efficiency was measured by flow cytometry. Cell perturbation was assessed by immune gene expression profiling, including an electroporation comparator. In vitro and in vivo cytotoxicity of chimeric antigen receptor (CAR) T cells generated using the Solupore system was evaluated using a real-time cellular impedance assay and a Raji-luciferase mouse tumor model, respectively.

Results

Efficient transfection was demonstrated through delivery of mRNA and CRISPR CAS9 RNP cargos individually, simultaneously and sequentially using the Solupore system while consistently maintaining high levels of cell viability. Gene expression profiling revealed minimal alteration in immune gene expression, demonstrating the low level of perturbation experienced by the cells during this transfection process. By contrast, electroporation resulted in substantial changes in immune gene expression in T cells. CAR T cells generated using the Solupore system exhibited efficient cytotoxicity against target cancer cells in vitro and in vivo.

Conclusions

The Solupore system is a non-viral means of simply, rapidly and efficiently delivering cargos to primary human immune cells with retention of high cell viability and functionality.

Do depressive symptoms and subjective well-being influence the valence or visual perspective of autobiographical memories in young adults?

The present study examines predictors of autobiographical memory valence and visual perspective. Participants (N = 144) between the ages of 18-35 years completed an online survey assessing depressive symptoms, and different aspects of subjective well-being (i.e., life satisfaction, positive affect, and negative affect). Participants retrieved six autobiographical memories cued via positive, negative, and neutral words and completed a questionnaire assessing characteristics of the memories, including memory valence and visual perspective. Using structural equation modelling, we found that the valence of neutral cued memories were significantly negatively associated with depressive symptoms and negative affect, and significantly positively associated with life satisfaction, even after controlling for current mood. Depressive symptoms were generally not significantly related to visual perspective. These results support previous findings that depressive symptoms and well-being are related to differences in memory characteristics but suggest that some of the relationships may be less robust when examined in a non-clinical sample.

Trends in kidney function testing in UK primary care since the introduction of the quality and outcomes framework: a retrospective cohort study using CPRD

OBJECTIVES

To characterise serum creatinine and urinary protein testing in UK general practices from 2005 to 2013 and to examine how the frequency of testing varies across demographic factors, with the presence of chronic conditions and with the prescribing of drugs for which kidney function monitoring is recommended.

DESIGN

Retrospective open cohort study.

SETTING

Routinely collected data from 630 UK general practices contributing to the Clinical Practice Research Datalink.

PARTICIPANTS

4 573 275 patients aged over 18 years registered at up-to-standard practices between 1 April 2005 and 31 March 2013. At study entry, no patients were kidney transplant donors or recipients, pregnant or on dialysis.

PRIMARY OUTCOME MEASURES

The rate of serum creatinine and urinary protein testing per year and the percentage of patients with isolated and repeated testing per year.

RESULTS

The rate of serum creatinine testing increased linearly across all age groups. The rate of proteinuria testing increased sharply in the 2009-2010 financial year but only for patients aged 60 years or over. For patients with established chronic kidney disease (CKD), creatinine testing increased rapidly in 2006-2007 and 2007-2008, and proteinuria testing in 2009-2010, reflecting the introduction of Quality and Outcomes Framework indicators. In adjusted analyses, CKD Read codes were associated with up to a twofold increase in the rate of serum creatinine testing, while other chronic conditions and potentially nephrotoxic drugs were associated with up to a sixfold increase. Regional variation in serum creatinine testing reflected country boundaries.

CONCLUSIONS

Over a nine-year period, there have been increases in the numbers of patients having kidney function tests annually and in the frequency of testing. Changes in the recommended management of CKD in primary care were the primary determinant, and increases persist even after controlling for demographic and patient-level factors. Future studies should address whether increased testing has led to better outcomes.

Computer-assisted Control of a Waiting List

The main objective in the use of computer-based systems which dynamically order hospital waiting lists is to produce a more systematic and clinically acceptable pattern of selection from the waiting list than that resulting from traditional manual systems. This has been achieved previously through the evaluation of fairly complex mathematical formulae which require detailed analysis to modify their behaviour pattern, and thus separate the clinician from direct control of the system.

This paper describes a waiting list management system which uses a conceptually simple ordering process based on waiting time limits set by the clinician for each planned clinical procedure relevant to the specialty. The clinician receives periodic analyses of the current performance of the process and can easily control the behaviour pattern by changing the limits for any procedure. The system also keeps account of allocated bed and theatre resources.

Use of this waiting list management system in a Urology Department has resulted in a significant shift in the composition of the waiting list and in a more equitable pattern of selection from the waiting list;. In addition, the time spent by the clinician in managing the waiting list has been considerably reduced.

Domestic light at night and breast cancer risk: a prospective analysis of 105 000 UK women in the Generations Study

Background:

Circadian disruption caused by exposure to light at night (LAN) has been proposed as a risk factor for breast cancer and a reason for secular increases in incidence. Studies to date have largely been ecological or case-control in design and findings have been mixed.

Methods:

We investigated the relationship between LAN and breast cancer risk in the UK Generations Study. Bedroom light levels and sleeping patterns at age 20 and at study recruitment were obtained by questionnaire. Analyses were conducted on 105 866 participants with no prior history of breast cancer. During an average of 6.1 years of follow-up, 1775 cases of breast cancer were diagnosed. Cox proportional hazard models were used to calculate hazard ratios (HRs), adjusting for potential confounding factors.

Results:

There was no association between LAN level and breast cancer risk overall (highest compared with lowest LAN level at recruitment: HR=1.01, 95% confidence interval (CI): 0.88–1.15), or for invasive (HR=0.98, 95% CI: 0.85–1.13) or in situ (HR=0.96, 95% CI: 0.83–1.11) breast cancer, or oestrogen-receptor (ER) positive (HR=0.98, 95% CI: 0.84–1.14); or negative (HR=1.16, 95% CI: 0.82–1.65) tumours separately. The findings did not differ by menopausal status. Adjusting for sleep duration, sleeping at unusual times (non-peak sleep) and history of night work did not affect the results. Night waking with exposure to light, occurring around age 20, was associated with a reduced risk of premenopausal breast cancer (HR for breast cancer overall=0.74, 95% CI: 0.55–0.99; HR for ER-positive breast cancer=0.69, 95% CI: 0.49–0.97).

Conclusions:

In this prospective cohort analysis of LAN, there was no evidence that LAN exposure increased the risk of subsequent breast cancer, although the suggestion of a lower breast cancer risk in pre-menopausal women with a history of night waking in their twenties may warrant further investigation.

Comparative effectiveness of injectable penicillin versus a combination of penicillin and gentamicin in children with pneumonia characterised by indrawing in Kenya: a retrospective observational study

OBJECTIVES

Kenyan guidelines for antibiotic treatment of pneumonia recommended treatment of pneumonia characterised by indrawing with injectable penicillin alone in inpatient settings until early 2016. At this point, they were revised becoming consistent with WHO guidance after results of a Kenyan trial provided further evidence of equivalence of oral amoxicillin and injectable penicillin. This change also made possible use of oral amoxicillin for outpatient treatment in this patient group. However, given non-trivial mortality in Kenyan children with indrawing pneumonia, it remained possible they would benefit from a broader spectrum antibiotic regimen. Therefore, we compared the effectiveness of injectable penicillin monotherapy with a regimen combining penicillin with gentamicin.

SETTING

We used a large routine observational dataset that captures data on all admissions to 13 Kenyan county hospitals.

PARTICIPANTS AND MEASURES

The analyses included children aged 2-59 months. Selection of study population was based on inclusion criteria typical of a prospective trial, primary analysis (experiment 1, n=4002), but we also explored more pragmatic inclusion criteria (experiment 2, n=6420) as part of a secondary analysis. To overcome the challenges associated with the non-random allocation of treatments and missing data, we used propensity score (PS) methods and multiple imputation to minimise bias. Further, we estimated mortality risk ratios using log binomial regression and conducted sensitivity analyses using an instrumental variable and PS trimming.

RESULTS

The estimated risk of dying, in experiment 1, in those receiving penicillin plus gentamicin was 1.46 (0.85 to 2.43) compared with the penicillin monotherapy group. In experiment 2, the estimated risk was 1.04(0.76 to 1.40).

CONCLUSION

There is no statistical difference in the treatment of indrawing pneumonia with either penicillin or penicillin plus gentamicin. By extension, it is unlikely that treatment with penicillin plus gentamicin would offer an advantage to treatment with oral amoxicillin.

Randomized controlled trial of honey versus mupirocin to decolonize patients with nasal colonization of meticillin-resistant Staphylococcus aureus

BACKGROUND

Mupirocin is used specifically for the eradication of nasal meticillin-resistant Staphylococcus aureus (MRSA), but increasing mupirocin resistance restricts its repeated use. The antibacterial effects of manuka honey have been established in vitro; antibacterial activity of other honeys has also been reported.

AIM

To describe the learning experience from a randomized controlled trial (RCT) comparing the efficacy of medical-grade honey (MGH) with mupirocin 2% for the eradication of nasal MRSA.

METHODS

Patients colonized in the nose with MRSA and age ≥18 years were recruited. Participants received either one or two courses of MGH or mupirocin 2%, three times per day for five consecutive days.

FINDINGS

The proportion of patients who were decolonized after one or two courses of treatment was not significantly different between MGH [18/42; 42.8%; 95% confidence interval (CI): 27.7-59.0] and mupirocin 2% (25/44; 56.8%; 95% CI: 41.0-71.7). Non-nasal MRSA colonization was significantly associated with persistent nasal colonization (odds ratio: 5.186; 95% CI: 1.736-5.489; P = 0.003). The rate of new acquisition of mupirocin resistance was 9.75%.

CONCLUSION

Although not significant, a decolonization rate of 42.8% for MGH was impressive. Our findings suggest that this strategy, which has the potential to combat antimicrobial resistance, should be assessed in similar but larger studies.

Handling missing data in propensity score estimation in comparative effectiveness evaluations: a systematic review

Aim

Even though systematic reviews have examined how aspects of propensity score methods are used, none has reviewed how the challenge of missing data is addressed with these methods. This review there-fore describes how missing data are addressed with propensity score methods in observational comparative effectiveness studies.

Methods

Published articles on observational comparative effectiveness studies were extracted from MEDLINE and EMBASE databases.

Results

Our search yielded 167 eligible articles. Majority of these studies (114; 68%) conducted complete case analysis with only 53 of them stating this in the methods. Only 16 articles reported use of multiple imputation.

Conclusion

Few researchers use correct methods for handling missing data or reported missing data methodology which may lead to reporting biased findings.

Comparative effectiveness of injectable penicillin versus a combination of penicillin and gentamicin in children with pneumonia characterised by indrawing in Kenya: protocol for an observational study

INTRODUCTION

WHO treatment guidelines are widely recommended for guiding treatment for millions of children with pneumonia every year across multiple low-income and middle-income countries. Guidelines are based on synthesis of available evidence that provides moderate certainty in evidence of effects for forms of pneumonia that can result in hospitalisation. However, trials have included fewer children from Africa than other settings, and it is suggested that African children with pneumonia have higher mortality. Thus, despite improving access to recommended treatments and deployment with high coverage of childhood vaccines, pneumonia remains one of the top causes of mortality for children in Kenya. Establishing whether there are benefits of alternative treatment regimens to help reduce mortality would require pragmatic clinical trials. However, these remain relatively expensive and time consuming. This protocol describes an approach to using secondary analysis of a new, large observational dataset as a potentially cheaper and quicker way to examine the comparative effectiveness of penicillin versus penicillin plus gentamicin in treatment of indrawing pneumonia. Addressing this question is important, as although it is now recommended that this form of pneumonia is treated with oral medication as an outpatient, it remains associated with non-trivial mortality that may be higher outside trial populations.

METHODS AND ANALYSIS

We will use a large observational dataset that captures data on all admissions to 13 Kenyan county hospitals. These data represent the findings of clinicians in practice and, because the system was developed for large observational research, pose challenges of non-random treatment allocation and missing data. To overcome these challenges, this analysis will use a rigorous approach to study design, propensity score methods and multiple imputation to minimise bias.

ETHICS AND DISSEMINATION

The primary data are held by hospitals participating in the Kenyan Clinical Information Network project with de-identifed data shared with the Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme for agreed analyses. The use of data for the analysis described received ethical clearance from the KEMRI scientific and ethical review committee. The findings of this analysis will be published.

Evaluation of fixed and variable hospital costs due to Clostridium difficile infection: institutional incentives and directions for future research

BACKGROUND

Economic analysis of Clostridium difficile infection (CDI) should consider the incentives facing institutional decision-makers. To avoid overstating the financial benefits of infection prevention, fixed and variable costs should be distinguished.

AIM

To quantify CDI fixed and variable costs in a tertiary referral hospital during August 2015.

METHODS

A micro-costing analysis estimated CDI costs per patient, including the additional costs of a CDI outbreak. Resource use was quantified after review of patient charts, pharmacy data, administrative resource input, and records of salary and cleaning/decontamination expenditure.

FINDINGS

The incremental cost of CDI was €75,680 (mean: €5,820 per patient) with key cost drivers being cleaning, pharmaceuticals, and length of stay (LOS). Additional LOS ranged from 1.75 to 22.55 days. For seven patients involved in a CDI outbreak, excluding the value of the 58 lost bed-days (€34,585); costs were 30% higher (€7,589 per patient). Therefore, total spending on CDI was €88,062 (mean: €6,773 across all patients). Potential savings from variable costs were €1,026 (17%) or €1,768 (26%) if outbreak costs were included. Investment in an antimicrobial pharmacist would require 47 CDI cases to be prevented annually. Prevention of 5%, 10% and 20% CDI would reduce attributable costs by €4,403, €8,806 and €17,612. Increasing the incremental LOS attributable to CDI to seven days per patient would have increased costs to €7,478 or €8,431 (if outbreak costs were included).

CONCLUSION

As much CDI costs are fixed, potential savings from infection prevention are limited. Future analysis must consider more effectively this distinction and its impact on institutional decision-making.

Diabetes screening intervals based on risk stratification

BACKGROUND

Guidelines for frequency of Type 2 diabetes mellitus (DM) screening remain unclear, with proposed screening intervals typically based on expert opinion. This study aims to demonstrate that HbA1c screening intervals may differ substantially when considering individual risk for diabetes.

METHODS

This was a multi-institutional retrospective open cohort study. Data were collected between April 1999 to March 2014 from one urban and one rural cohort in Japan. After categorization by age, we stratified individuals based on cardiovascular disease risk (Framingham 10-year cardiovascular risk score) and body mass index (BMI). We adapted a signal-to-noise method for distinguishing true HbA1c change from measurement error by constructing a linear random effect model to calculate signal and noise of HbA1c. Screening interval for HbA1c was defined as informative when the signal-to-noise ratio exceeded 1.

RESULTS

Among 96,456 healthy adults, 46,284 (48.0%) were male; age (range) and mean HbA1c (SD) were 48 (30-74) years old and 5.4 (0.4)%, respectively. As risk increased among those 30-44 years old, HbA1c screening intervals for detecting Type 2 DM consistently decreased: from 10.5 (BMI <18.5) to 2.4 (BMI > 30) years, and from 8.0 (Framingham Risk Score <10%) to 2.0 (Framingham Risk Score ≥20%) years. This trend was consistent in other age and risk groups as well; among obese 30-44 year olds, we found substantially shorter intervals compared to other groups.

CONCLUSION

HbA1c screening intervals for identification of DM vary substantially by risk factors. Risk stratification should be applied when deciding an optimal HbA1c screening interval in the general population to minimize overdiagnosis and overtreatment.

Menopausal hormone therapy and breast cancer: what is the true size of the increased risk?

BACKGROUND

Menopausal hormone therapy (MHT) increases breast cancer risk; however, most cohort studies omit MHT use after enrolment and many infer menopausal age.

METHODS

We used information from serial questionnaires from the UK Generations Study cohort to estimate hazard ratios (HRs) for breast cancer among post-menopausal women with known menopausal age, and examined biases induced when not updating data on MHT use and including women with inferred menopausal age.

RESULTS

Among women recruited in 2003-2009, at 6 years of follow-up, 58 148 had reached menopause and 96% had completed a follow-up questionnaire. Among 39 183 women with known menopausal age, 775 developed breast cancer, and the HR in relation to current oestrogen plus progestogen MHT use (based on 52 current oestrogen plus progestogen MHT users in breast cancer cases) relative to those with no previous MHT use was 2.74 (95% confidence interval (CI): 2.05-3.65) for a median duration of 5.4 years of current use, reaching 3.27 (95% CI: 1.53-6.99) at 15+ years of use. The excess HR was underestimated by 53% if oestrogen plus progestogen MHT use was not updated after recruitment, 13% if women with uncertain menopausal age were included, and 59% if both applied. The HR for oestrogen-only MHT was not increased (HR=1.00; 95% CI: 0.66-1.54).

CONCLUSIONS

Lack of updating MHT status through follow-up and inclusion of women with inferred menopausal age is likely to result in substantial underestimation of the excess relative risks for oestrogen plus progestogen MHT use in studies with long follow-up, limited updating of exposures, and changing or short durations of use.

Optimal strategies for monitoring lipid levels in patients at risk or with cardiovascular disease: a systematic review with statistical and cost-effectiveness modelling

BACKGROUND

Various lipid measurements in monitoring/screening programmes can be used, alone or in cardiovascular risk scores, to guide treatment for prevention of cardiovascular disease (CVD). Because some changes in lipids are due to variability rather than true change, the value of lipid-monitoring strategies needs evaluation.

OBJECTIVE

To determine clinical value and cost-effectiveness of different monitoring intervals and different lipid measures for primary and secondary prevention of CVD.

DATA SOURCES

We searched databases and clinical trials registers from 2007 (including the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, the Clinical Trials Register, the Current Controlled Trials register, and the Cumulative Index to Nursing and Allied Health Literature) to update and extend previous systematic reviews. Patient-level data from the Clinical Practice Research Datalink and St Luke's Hospital, Japan, were used in statistical modelling. Utilities and health-care costs were drawn from the literature.

METHODS

In two meta-analyses, we used prospective studies to examine associations of lipids with CVD and mortality, and randomised controlled trials to estimate lipid-lowering effects of atorvastatin doses. Patient-level data were used to estimate progression and variability of lipid measurements over time, and hence to model lipid-monitoring strategies. Results are expressed as rates of true-/false-positive and true-/false-negative tests for high lipid or high CVD risk. We estimated incremental costs per quality-adjusted life-year.

RESULTS

A total of 115 publications reported strength of association between different lipid measures and CVD events in 138 data sets. The summary adjusted hazard ratio per standard deviation of total cholesterol (TC) to high-density lipoprotein (HDL) cholesterol ratio was 1.25 (95% confidence interval 1.15 to 1.35) for CVD in a primary prevention population but heterogeneity was high (I(2) = 98%); similar results were observed for non-HDL cholesterol, apolipoprotein B and other ratio measures. Associations were smaller for other single lipid measures. Across 10 trials, low-dose atorvastatin (10 and 20 mg) effects ranged from a TC reduction of 0.92 mmol/l to 2.07 mmol/l, and low-density lipoprotein reduction of between 0.88 mmol/l and 1.86 mmol/l. Effects of 40 mg and 80 mg were reported by one trial each. For primary prevention, over a 3-year period, we estimate annual monitoring would unnecessarily treat 9 per 1000 more men (28 vs. 19 per 1000) and 5 per 1000 more women (17 vs. 12 per 1000) than monitoring every 3 years. However, annual monitoring would also undertreat 9 per 1000 fewer men (7 vs. 16 per 1000) and 4 per 1000 fewer women (7 vs. 11 per 1000) than monitoring at 3-year intervals. For secondary prevention, over a 3-year period, annual monitoring would increase unnecessary treatment changes by 66 per 1000 men and 31 per 1000 women, and decrease undertreatment by 29 per 1000 men and 28 per 1000 men, compared with monitoring every 3 years. In cost-effectiveness, strategies with increased screening/monitoring dominate. Exploratory analyses found that any unknown harms of statins would need utility decrements as large as 0.08 (men) to 0.11 (women) per statin user to reverse this finding in primary prevention.

LIMITATION

Heterogeneity in meta-analyses.

CONCLUSIONS

While acknowledging known and potential unknown harms of statins, we find that more frequent monitoring strategies are cost-effective compared with others. Regular lipid monitoring in those with and without CVD is likely to be beneficial to patients and to the health service. Future research should include trials of the benefits and harms of atorvastatin 40 and 80 mg, large-scale surveillance of statin safety, and investigation of the effect of monitoring on medication adherence.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013003727.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Psychological stress, adverse life events and breast cancer incidence: a cohort investigation in 106,000 women in the United Kingdom

Background

Women diagnosed with breast cancer frequently attribute their cancer to psychological stress, but scientific evidence is inconclusive. We investigated whether experienced frequency of stress and adverse life events affect subsequent breast cancer risk.

Methods

Breast cancer incidence was analysed with respect to stress variables collected at enrolment in a prospective cohort study of 106,000 women in the United Kingdom, with 1783 incident breast cancer cases. Relative risks (RR) were obtained as hazard ratios using Cox proportional hazards models.

Results

There was no association of breast cancer risk overall with experienced frequency of stress. Risk was reduced for death of a close relative during the 5 years preceding study entry (RR = 0.87, 95 % confidence interval (CI): 0.78–0.97), but not for death of a spouse/partner or close friend, personal illness/injury, or divorce/separation. There was a positive association of divorce with oestrogen-receptor-negative (RR = 1.54, 95 % CI: 1.01–2.34), but not with oestrogen-receptor-positive breast cancer. Risk was raised in women who were under age 20 at the death of their mother (RR = 1.31, 95 % CI: 1.02–1.67), but not of their father, and the effect was attenuated after excluding mothers with breast or ovarian cancer (RR = 1.17, 95 % CI: 0.85–1.61).

Conclusions

This large prospective study did not show consistent evidence for an association of breast cancer risk with perceived stress levels or adverse life events in the preceding 5 years, or loss of parents during childhood and adolescence.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0733-1) contains supplementary material, which is available to authorized users.

Disease-specific quality of life in multiple sclerosis: the effect of disease modifying treatment

Disease specific quality of life was measured in the Leeds Multiple Sclerosis (MS) Treatment Programme (n-/210) using the self-report Leeds MS Quality of Life (LMSQoL) scale. The results showed a significant and sustained increase in quality of life associated with ‘disease modifying’ treatment. This contrasts with the Expanded Disability Status Scores (EDSS), which showed no measurable improvement. An increase in the LMSQoL score did not correlate with baseline age, disease duration, disability or number of prior relapses. There was no significant difference in treatment effect between relapsing-remitting and secondary progressive MS patients, or between patients receiving different products. However, patients with a poor quality of life at baseline showed the most benefit from treatment. Those who had their treatment stopped due to progression, side-effects or lack of effect had significantly lower LMSQoL scores on treatment. In this study, the LMSQoL scale was responsive to change and was easy to administer in a clinical setting.

Trends in serum creatinine testing in Oxfordshire, UK, 1993-2013: a population-based cohort study

OBJECTIVES

To determine how many kidney function tests are done, on whom, how frequently they are performed and how they have changed over time.

DESIGN

Retrospective study of all serum creatinine, urine albumin and urine creatinine tests.

SETTING

Primary and secondary care in Oxfordshire from 1993 to 2013.

PARTICIPANTS

Unselected population of 1,220,447 people.

MAIN OUTCOME MEASURES

The total number of creatinine and urinary protein tests ordered from primary and secondary care and the number of tests per year stratified by categories of estimated glomerular filtration rate (eGFR). The frequency of testing in patients having their kidney function monitored.

RESULTS

Creatinine requests from primary care increased steadily from 1997 and exceeded 220,000 requests in 2013. Tests corresponding to normal kidney function (eGFR >60/mL/min/1.73 m(2)) constituted 59% of all kidney function tests in 1993 and accounted for 83% of all tests in 2013. Test corresponding to chronic kidney disease (CKD) stages 3-5 declined after 2007. Reduced kidney function, albuminuria, male gender, diabetes and age were independently associated with more frequent monitoring. For a female patient between 61 and 80 years and with stage 3a CKD, the average number of serum creatinine tests (95% CI) was 3.23/year (3.19 to 3.26) and for a similar woman with diabetes, the average number of tests was 5.50 (5.44 to 5.56) tests per year.

CONCLUSIONS

There has been a large increase in the number of kidney function tests over the past two decades. However, we found little evidence that this increase is detecting more CKD. Tests are becoming more frequent in people with and without evidence of renal impairment. Future work using a richer data source could help unravel the underlying reasons for the increased testing and determine how much is necessary and useful.

Implications of lower risk thresholds for statin treatment in primary prevention: analysis of CPRD and simulation modelling of annual cholesterol monitoring

OBJECTIVE

To estimate numbers affected by a recent change in UK guidelines for statin use in primary prevention of cardiovascular disease.

METHOD

We modelled cholesterol ratio over time using a sample of 45,151 men (≥40years) and 36,168 women (≥55years) in 2006, without statin treatment or previous cardiovascular disease, from the Clinical Practice Research Datalink. Using simulation methods, we estimated numbers indicated for new statin treatment, if cholesterol was measured annually and used in the QRISK2 CVD risk calculator, using the previous 20% and newly recommended 10% thresholds.

RESULTS

We estimate that 58% of men and 55% of women would be indicated for treatment by five years and 71% of men and 73% of women by ten years using the 20% threshold. Using the proposed threshold of 10%, 84% of men and 90% of women would be indicated for treatment by 5years and 92% of men and 98% of women by ten years.

CONCLUSION

The proposed change of risk threshold from 20% to 10% would result in the substantial majority of those recommended for cholesterol testing being indicated for statin treatment. Implications depend on the value of statins in those at low to medium risk, and whether there are harms.

The relationship between obesity and exposure to light at night: cross-sectional analyses of over 100,000 women in the Breakthrough Generations Study

There has been a worldwide epidemic of obesity in recent decades. In animal studies, there is convincing evidence that light exposure causes weight gain, even when calorie intake and physical activity are held constant. Disruption of sleep and circadian rhythms by exposure to light at night (LAN) might be one mechanism contributing to the rise in obesity, but it has not been well-investigated in humans. Using multinomial logistic regression, we examined the association between exposure to LAN and obesity in questionnaire data from over 100,000 women in the Breakthrough Generations Study, a cohort study of women aged 16 years or older who were living in the United Kingdom and recruited during 2003-2012. The odds of obesity, measured using body mass index, waist:hip ratio, waist:height ratio, and waist circumference, increased with increasing levels of LAN exposure (P < 0.001), even after adjustment for potential confounders such as sleep duration, alcohol intake, physical activity, and current smoking. We found a significant association between LAN exposure and obesity which was not explained by potential confounders we could measure. While the possibility of residual confounding cannot be excluded, the pattern is intriguing, accords with the results of animal experiments, and warrants further investigation.

Timing of pubertal stages and breast cancer risk: the Breakthrough Generations Study

INTRODUCTION

Breast development and hormonal changes at puberty might affect breast cancer risk, but epidemiological analyses have focussed largely on age at menarche and not at other pubertal stages.

METHODS

We investigated associations between the timing of pubertal stages and breast cancer risk using data from a cohort study of 104,931 women (Breakthrough Generations Study, UK, 2003-2013). Pubertal variables were reported retrospectively at baseline. Breast cancer risk was analysed using Cox regression models with breast cancer diagnosis as the outcome of interest, attained age as the underlying time variable, and adjustment for potentially confounding variables.

RESULTS

During follow-up (mean = 4.1 years), 1094 breast cancers (including ductal carcinoma in situ) occurred. An increased breast cancer risk was associated with earlier thelarche (age when breast growth begins; HR [95% CI] = 1.23 [1.02, 1.48], 1 [referent] and 0.80 [0.69, 0.93] for ≤10, 11-12 and ≥13 years respectively), menarche (initiation of menses; 1.06 [0.93, 1.21], 1 [referent] and 0.78 [0.62, 0.99] for ≤12, 13-14 and ≥15 years), regular periods (0.99 [0.83, 1.18], 1 [referent] and 0.74 [0.59, 0.92] for ≤12, 13-14 and ≥15 years) and age reached adult height (1.25 [1.03, 1.52], 1 [referent] and 1.07 [0.87, 1.32] for ≤14, 15-16 and ≥17 years), and with increased time between thelarche and menarche (0.87 [0.65, 1.15], 1 [referent], 1.14 [0.96, 1.34] and 1.27 [1.04, 1.55] for <0, 0, 1 and ≥2 years), and shorter time between menarche and regular periods (1 [referent], 0.87 [0.73, 1.04] and 0.66 [0.50, 0.88] for 0, 1 and ≥2 years). These associations were generally similar when considered separately for premenopausal and postmenopausal breast cancer.

CONCLUSIONS

Breast duct development may be a time of heightened susceptibility to risk of carcinogenesis, and greater attention needs to be given to the relation of breast cancer risk to the different stages of puberty.

Body mass index, exercise, and other lifestyle factors in relation to age at natural menopause: analyses from the breakthrough generations study

The authors examined the effect of women's lifestyles on the timing of natural menopause using data from a cross-sectional questionnaire used in the United Kingdom-based Breakthrough Generations Study in 2003-2011. The analyses included 50,678 women (21,511 who had experienced a natural menopause) who were 40-98 years of age at study entry and did not have a history of breast cancer. Cox competing risks proportional hazards models were fitted to examine the relation of age at natural menopause to lifestyle and anthropometric factors. Results were adjusted for age at reporting, smoking status at menopause, parity, and body mass index at age 40 years, as appropriate. All P values were 2-sided. High adult weight (P(trend) < 0.001), high body mass index (P(trend) < 0.001), weight gain between the ages of 20 and 40 years (P(trend) = 0.01), not smoking (P < 0.001), increased alcohol consumption (P(trend) < 0.001), regular strenuous exercise (P < 0.01), and not being a vegetarian (P < 0.001) were associated with older age at menopause. Neither height nor history of an eating disorder was associated with menopausal age. These findings show the importance of lifestyle factors in determining menopausal age.

Coronary plaque burden in patients with stable and unstable coronary artery disease using multislice CT coronary angiography

PURPOSE

We evaluated the multislice computed tomography (MSCT) coronary plaque burden in patients with stable and unstable angina pectoris.

MATERIALS AND METHODS

Twenty-one patients with stable and 20 with unstable angina pectoris scheduled for conventional coronary angiography (CCA) underwent MSCT-CA using a 64-slice scanner offering a fast rotation time (330 ms) and higher X-ray tube output (900 mAs). To determine the MSCT coronary plaque burden, we assessed the extent (number of diseased segments), size (small or large), type (calcific, noncalcific, mixed) of plaque, its anatomic distribution and angiographic appearance in all available ≥2-mm segments. In a subset of 15 (seven stable, eight unstable) patients, the detection and classification of coronary plaques by MSCT was verified by intracoronary ultrasound (ICUS).

RESULTS

Sensitivity and specificity of MSCT compared with ICUS to detect significant plaques (defined as ≥1-mm plaque thickness on ICUS) was 83% and 87%. Overall, 473 segments were examined, resulting in 11.6±1.5 segments per patient. Plaques were present in 62% of segments and classified as large in 47% of diseased segments. Thirty-two percent were noncalcific, 25% calcific and 43% mixed. Plaques were most frequently located in the proximal and mid segments. Plaque was found in 33% of segments classified as normal on CCA. Unstable patients had significantly more noncalcific plaques when compared with stable patients (45% vs. 21%, p<0.05).

CONCLUSIONS

MSCT-CA provides important information regarding the coronary plaque burden in patients with stable and unstable angina.

How far can we explain the social class differential in respiratory function? A cross-sectional population study of 21,991 men and women from EPIC-Norfolk

The objective of this study is to investigate the association between occupational social class and respiratory function, as measured by forced expiratory volume in one-second (FEV(1)). We examined the cross sectional relationship between lung function and social class in a population study of 21,991 men and women aged 39-79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age-sex registers in 1993-1997. There was a significant socioeconomic gradient in age adjusted lung function with a difference of 0.37 in mean FEV(1) in men and 0.20 in women, respectively between social class I and V. The age adjusted OR for having poor lung function was 4.13 (95% CI 2.66-6.42) in men and 2.64 (95% CI 1.74-3.99) in women for social class V compared to I. This difference was substantially attenuated after adjustment for height, weight, smoking status, respiratory illness, educational level, living in a deprived area, physical activity and plasma vitamin C levels. There was a strong socioeconomic gradient in respiratory function. In men the gradient appeared to be largely explained by smoking status and height; in women a large part of the gradient was explained by potentially modifiable factors. This suggests that socioeconomic inequalities in respiratory function may be preventable or modifiable and highlights factors for further exploration.

Social class, risk factors, and stroke incidence in men and women: a prospective study in the European prospective investigation into cancer in Norfolk cohort

BACKGROUND AND PURPOSE

The purpose of this study was to investigate the association between occupational social class and stroke incidence and the extent to which classical, lifestyle, and psychosocial risk factors may explain such relationships.

METHODS

A prospective population study was conducted of 22488 men and women aged 39 to 79 years living in the general community in Norfolk, UK, recruited in 1993 to 1997 and followed up for stroke incidence to 2007.

RESULTS

An inverse relationship was observed between social class and stroke incidence with an age- and sex-adjusted hazard ratio for social Class V compared with I of 2.62 (95% CI, 1.63 to 4.22; P=0.001). Adjusting for classical (systolic blood pressure, total blood cholesterol, smoking, history of diabetes, and body mass index), lifestyle (plasma vitamin C levels, alcohol intake, and physical activity), and psychosocial (5-item version of the Mental Health Inventory) risk factors had little effect, and a socioeconomic differential was still apparent: hazard ratio for social Class V compared with I of 2.55 (95% CI, 1.34 to 4.85, P=0.004 for comparison of V to I).

CONCLUSIONS

Stroke incidence increased with lower social class in both men and women. Adjustment for a comprehensive range of classical, lifestyle, and psychosocial risk factors did not explain the socioeconomic differential in stroke incidence. If we are to reduce inequalities in health, further understanding of the mechanisms underlying the association is needed.

Self-rated health does not explain the socioeconomic differential in mortality: a prospective study in the EPIC-Norfolk cohort

BACKGROUND

Self-rated health (SRH), a subjective measure of health, is strongly predictive of mortality, independently of objective measures of health status and existing known disease. There is a strong social gradient in SRH. An investigation was carried to determine whether SRH can explain the well-known socioeconomic gradient in mortality.

METHODS

The effect of adjusting for SRH on the socioeconomic differential in mortality was examined in a prospective study of 20 754 men and women aged 39-79 years, without prevalent disease, living in the general community in Norfolk, UK, recruited using general practice age-sex registers for 1993-1997 and followed up for an average of 10 years.

RESULTS

Mortality risk increased with decreasing social class in men and women. There was some attenuation after adjustment for covariates age, body mass index, smoking, history of diabetes, systolic blood pressure, cholesterol level, alcohol consumption, physical activity and educational level, but a gradient remained. Further adjustment for SRH attenuated the association slightly more, but there was still some evidence of a socioeconomic differential in mortality, particularly in class V compared with class I (age- and sex-adjusted hazard ratio 1.57; 95% CI 1.19 to 2.06).

CONCLUSIONS

SRH does not substantially explain the socioeconomic differential in mortality beyond that explained by health-related covariates.

Social inequalities in self-rated health by age: cross-sectional study of 22,457 middle-aged men and women

Background

We investigate the association between occupational social class and self-rated health (SRH) at different ages in men and women.

Methods

Cross sectional population study of 22 457 men and women aged 39–79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age-sex registers in 1993–1997. The relationship between self-rated health and social class was examined using logistic regression, with a poor or moderate rating as the outcome.

Results

The prevalence of poor or moderate (lower) self-rated health increased with increasing age in both men and women. There was a strong social class gradient: in manual classes, men and women under 50 years of age had a prevalence of lower self-rated health similar to that seen in men and women in non-manual social classes over 70 years old. Even after adjustment for age, educational status, and lifestyle factors (body mass index (BMI), smoking, physical activity and alcohol consumption) there was still strong evidence of a social gradient in self-rated health, with unskilled men and women approximately twice as likely to report lower self-rated health as professionals (OR_men = 2.44 (95%CI 1.69, 3.50); OR_women = 1.97 (95%CI 1.45, 2.68).

Conclusion

There was a strong gradient of decreased SRH with age in both men and women. We found a strong cross-sectional association between SRH and social class, which was independent of education and major health related behaviors. The social class differential in SRH was similar with age. Prospective studies to confirm this association should explore social and emotional as well as physical pathways to inequalities in self reported health.

Occupational social class, educational level, smoking and body mass index, and cause-specific mortality in men and women: a prospective study in the European Prospective Investigation of Cancer and Nutrition in Norfolk (EPIC-Norfolk) cohort

OBJECTIVES

To investigate the independent associations between occupational and educational based measures of socioeconomic status (SES) and cause-specific mortality, and the extent to which potentially modifiable risk factors smoking and body mass index (BMI) explain such relationships.

DESIGN, SETTING AND PARTICIPANTS

Prospective population study of 22,486 men and women aged 39-79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age-sex registers in 1993-1997 and followed up for total mortality using death certification to 2006.

MAIN RESULTS

In men a strong inverse relationship was found between social class and all cause, cardiovascular and cancer mortality, with relative risk of social class V compared to I of 2.21 for all cause mortality (95% CI 1.54-3.17, P < 0.001). This was attenuated but not abolished after adjusting for modifiable risk factors, smoking and BMI, with relative risk of social class V compared to I for all cause mortality of 1.92 (95% CI 1.34-2.77, P < 0.001). A similar, but smaller effect was seen in women. Educational status was not associated with mortality independently of social class.

CONCLUSIONS

Social class and education are not necessarily interchangeable measures of SES. Some but not all of the socioeconomic differential in mortality can be explained by potentially modifiable risk factors smoking and BMI. Further understanding of the mechanisms underlying the association of each socioeconomic indicator with specific health outcomes is needed if we are to reduce inequalities in health.

Methodological considerations and approach to cross-technique comparisons using in vivo coronary plaque characterization based on intravascular ultrasound radiofrequency data analysis: insights from the Integrated Biomarker and Imaging Study (IBIS)

Grey scale intravascular ultrasound (IVUS) is a valuable clinical tool to assess the extent and severity of coronary atheroma. However, it cannot reliably identify plaques with a high-risk of future clinical events. Serial IVUS studies to assess the progression and/or regression of atherosclerotic plaques demonstrated only modest effects, of pharmacological intervention on plaque burden, even when clinical efficacy is documented. Spectral analysis of radiofrequency ultrasound data (IVUS-virtual histology (IVUS-VH), Volcano Therapeutics, Rancho Cordova, CA) has the potential to characterize accurately plaque composition. The Integrated Biomarker and Imaging Study (IBIS) evaluated both invasive and non-invasive imaging techniques along with the assessment of novel biomarkers to characterize sub-clinical atherosclerosis. IVUS-VH was not included at the start of the IBIS protocol. The purpose of this paper is to describe the methodology we used to obtain and analyse IVUS-VH images and the approach to cross-correlations with the other techniques.

Coronary artery remodelling is related to plaque composition

OBJECTIVE

To assess the potential relation between plaque composition and vascular remodelling by using spectral analysis of intravascular ultrasound (IVUS) radiofrequency data.

METHODS AND RESULTS

41 coronary vessels with non-significant (< 50% diameter stenosis by angiography), < or = 20 mm, non-ostial lesions located in non-culprit vessels underwent IVUS interrogation. IVUS radiofrequency data obtained with a 30 MHz catheter, were analysed with IVUS virtual histology software. A remodelling index (RI) was calculated and divided into three groups. Lesions with RI > or = 1.05 were considered to have positive remodelling and lesions with RI < or = 0.95 were considered to have negative remodelling. Lesions with RI > or = 1.05 had a significantly larger lipid core than lesions with RI 0.96-1.04 and RI < or = 0.95 (22.1 (6.3) v 15.1 (7.6) v 6.6 (6.9), p < 0.0001). A positive correlation between lipid core and RI (r = 0.83, p < 0.0001) and an inverse correlation between fibrous tissue and RI (r = -0.45, p = 0.003) were also significant. All of the positively remodelled lesions were thin cap fibroatheroma or fibroatheromatous lesions, whereas negatively remodelled lesions had a more stable phenotype, with 64% having pathological intimal thickening, 29% being fibrocalcific lesions, and only 7% fibroatheromatous lesions (p < 0.0001).

CONCLUSIONS

In this study, in vivo plaque composition and morphology assessed by spectral analysis of IVUS radiofrequency data were related to coronary artery remodelling.

The human G-protein β3 subunit C825T polymorphism is associated with coronary artery vasoconstriction

AIMS

Abnormal coronary vasomotion plays a role in the clinical expression of coronary artery disease. We hypothesized that the functional C825T polymorphism located in the ubiquitous G-protein beta3 subunit, implicated in the cellular signal transduction of many receptors, could modify artery coronary vasomotion. We assessed the potential association of the pertussis toxin-sensitive G protein beta3 subunit (GNB3) gene C825T polymorphism on coronary vasomotion in humans.

METHODS AND RESULTS

We examined the response of angiographically normal human coronary arteries (n=131) after intravenous injection of methylergonovine maleate, a vasoconstrictor, followed by injection of isosorbide dinitrate, a vasodilator, according to GNB3 genotypes. Coronary vasomotion was assessed with quantitative coronary angiography. Subjects bearing at least one T allele had greater susceptibility to vasoconstriction in response to methylergonovine maleate than CC subjects, whereas vasodilation in response to isosorbide dinitrate did not differ among the different genotypes.

CONCLUSION

The C825T polymorphism of the G-protein beta3 subunit may be a genetic determinant of coronary artery vasomotion in humans.

Paraoxonase polymorphism (Gln192Arg) as a determinant of the response of human coronary arteries to serotonin

Background-Oxidation of LDL plays a role in endothelial dysfunction. Paraoxonase, an enzyme present on HDL, protects LDL against oxidation. Paraoxonase activity is genetically determined in part, and 3 genotypes have been described with variable enzymatic activity. We hypothesized that the paraoxonase polymorphism might influence endothelial function. Methods and Results-Twenty-seven patients with clinical manifestations of coronary artery disease underwent provocative testing by intracoronary administration of serotonin. None of the coronary arteries studied had significant (>50%) stenosis. Ten patients had the QQ genotype and 17 had the QR genotype. At proximal segments, the mean percentage reduction in lumen diameter in response to serotonin was greater in QQ patients than in QR patients (10(-5) mol/L: P<0.05; 10(-4) mol/L: P<0.006). Similarly, at distal segments, constriction in response to serotonin was greater in QQ patients than in QR patients (10(-6) mol/L: P<0. 03; 10(-5) mol/L: P<0.07). Conclusions-These results suggest a higher synthesis or release of endothelium-derived relaxing factors to counteract the vasoconstrictor effect of serotonin in patients with the R allele. These findings provide evidence that the paraoxonase polymorphism may play a role in the regulation of coronary vasomotor tone.

[Restenosis after angioplasty]

Restenosis remains the main limitation of endocoronary methods of revascularisation. It is observed in 20 to over 50% of cases, depending on the prevailing risk factors and techniques used. The mechanism of post balloon angioplasty restenosis consists of neointimal hyperplasia, vascular remodelling and thrombosis. Intra-stent thrombosis is mainly caused by the neointimal hyperplasia. The strategies developed to prevent restenosis may be grouped in two categories: mechanical and pharmacological strategies. Stenting is the only mechanical method to have been shown to be effective. With respect to pharmacological methods, the general impression is rather negative even if some positive results have been reported recently. Of the new strategies which may provide a solution in the coming years, gene therapy and endocoronary irradiation justify a special mention.

Angiographically documented late reocclusion after successful coronary angioplasty of an infarct-related lesion is a powerful predictor of long-term mortality

BACKGROUND

Late reocclusion of an infarct-related artery (IRA) that was patent in the early days after acute myocardial infarction (MI) is a frequent event; the reocclusion rate may be as high as 30%. Few studies have been designed to analyze the impact of late reocclusion of the IRA on late survival.

METHODS AND RESULTS

We studied 528 patients who all had a patent IRA after a successful PTCA procedure 10+/-6 days after MI and who underwent systematic 6-month angiographic follow-up to assess late patency of the IRA. We compared long-term survival of patients with and without late reocclusion. Based on the results of 6-month follow-up angiography, 2 groups of patients were defined: (1) 90 patients (17%) with reocclusion (Thrombolysis In Myocardial Infarction [TIMI] flow 0 or 1) and (2) 438 patients (83%) without reocclusion. Long-term clinical follow-up was obtained for all 528 patients at a median of 5.7 years after follow-up angiography (6.4 years after PTCA). The overall actuarial 8-year total mortality rate was 13%. At the end of follow-up, there were 35 deaths (8%) among the 438 patients without reocclusion and 18 deaths (20%) among the 90 patients with reocclusion (P=0.002). The actuarial 8-year total mortality rate was 10% in patients without reocclusion and 28% in patients with reocclusion (P=0.0003). The actuarial cardiovascular mortality rate was 7% in patients without reocclusion and 25% in patients with reocclusion (P<0.0001). The impact of reocclusion on long-term mortality was greater in patients with anterior MI.

CONCLUSIONS

Late IRA patency is strongly associated with long-term survival after MI. These observations should encourage prospective studies to evaluate the impact of strategies designed to prevent late reocclusion in postinfarction patients.

Role of nitric oxide in restenosis after experimental balloon angioplasty in the hypercholesterolemic rabbit: effects on neointimal hyperplasia and vascular remodeling

OBJECTIVES

The purpose of this study was to assess the effects of L-arginine and N(G)-nitro-L-arginine methyl ester (L-NAME) on neointimal hyperplasia and vascular remodeling after balloon angioplasty in the hypercholesterolemic rabbit.

BACKGROUND

Restenosis after balloon angioplasty is a consequence of both neointimal hyperplasia and vessel remodeling. Nitric oxide inhibits neointimal hyperplasia, but its effect on vessel remodeling is unknown.

METHODS

Six weeks after induction of bilateral iliac atherosclerosis, 48 rabbits underwent successful angioplasty in 75 vessels. Eight rabbits (acute group) were sacrificed immediately after angioplasty. The remaining animals received either placebo (chronic control group), or a diet supplemented with either L-arginine (1.5 g/kg/day), or L-NAME (15 mg/kg/day) for 4 weeks after angioplasty.

RESULTS

The intimal area was significantly greater in the chronic control group compared to the acute group (2.60+/-1.03 mm2 vs. 1.35+/-0.62 mm2). This increase in intimal area was lower in the L-arginine group (1.79+/-0.61 mm2), and greater in the L-NAME group (3.23+/-0.92 mm2). The area circumscribed by the internal elastic lamina (IEL) increased significantly in the control group compared to the acute group (from 2.52+/-0.66 to 3.33+/-0.85 mm2); a more marked increase occurred in the L-NAME group (3.90+/-0.85 mm2). By contrast, IEL area was unchanged in the L-arginine group (2.41+/-0.62 mm2). As a result, there was no significant difference in lumen area after 4 weeks in the chronic groups (control: 0.74+/-0.38 mm2; L-arginine: 0.50+/-0.43 mm2; L-NAME: 0.48+/-0.42 mm2).

CONCLUSIONS

Our results demonstrate that L-arginine inhibits whereas L-NAME stimulates neointimal hyperplasia after experimental balloon angioplasty in the hypercholesterolemic rabbit. However, the lack of vessel enlargement in the L-arginine group resulted in a similar final lumen size in the L-NAME and L-arginine groups.