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

One-size-fits-all versus risk-category-based screening interval strategies for cardiovascular disease prevention in Chinese adults: a prospective cohort study

Background

In non-high-risk individuals, risk-category-based atherosclerotic cardiovascular disease (ASCVD) screening strategies may be more cost-effective than one-size-fits-all approaches. However, current decisions are constrained by a lack of research evidence. We aimed to explore appropriate risk-category-based screening interval strategies for non-high-risk individuals in ASCVD primary prevention in the Chinese population.

Methods

We used data from 28,624 participants in the China Kadoorie Biobank (CKB) who had completed at least two field surveys. The risk assessment tools were the 10-year ASCVD risk prediction models developed based on the CKB cohort. We constructed multistate Markov models to model disease progression and estimate transition probabilities between different risk categories. The total person-years spent unidentified in the high-risk state over a 10-year period were calculated for each screening interval protocol. We also estimated the number of ASCVD events prevented, quality-adjusted life years (QALYs) gained, and costs saved when compared to the 3-yearly screening protocol.

Findings

When compared to the uniform 3-yearly protocol, most risk-category-based screening interval protocols would identify more high-risk individuals timely, thus preventing more ASCVD events and gaining QALYs. A few of them would reduce total health-care costs. The protocol, which used 6-year, 3-year, and 2-year screening intervals for low-risk, intermediate-low-risk, and intermediate-high risk individuals, was optimal, and would reduce the person-years spent unidentified in the high-risk category by 17.9% (95% CI: 13.1%-21.9%), thus preventing an estimated 113 thousand (95% CI: 83-138) hard ASCVD events for Chinese adults aged 30-79 over a 10-year period. When using a lower cost of statin therapy, more screening protocols would gain QALYs while saving costs.

Interpretation

For the primary prevention of ASCVD, risk-category-based screening protocols outperformed the one-size-fits-all approach in the Chinese population.

Funding

This work was supported by National Natural Science Foundation of China (82192904, 82388102, 82192900) and grants (2023YFC2509400) from the National Key R&D Program of China. The CKB baseline survey and the first re-survey were supported by a grant from the Kadoorie Charitable Foundation in Hong Kong. The long-term follow-up is supported by grants from the UK Wellcome Trust (212946/Z/18/Z, 202922/Z/16/Z, 104085/Z/14/Z, 088158/Z/09/Z), grants (2016YFC0900500) from the National Key R&D Program of China, National Natural Science Foundation of China (81390540, 91846303, 81941018), and Chinese Ministry of Science and Technology (2011BAI09B01).

Canadian Society of Clinical Chemists Harmonized Pediatric Lipid Reporting Recommendations for Clinical Laboratories

Detecting dyslipidemia early is important because atherosclerosis originates in childhood and early treatment can improve outcomes. In 2022, the Canadian Cardiovascular Society (CCS) and Canadian Pediatric Cardiology Association (CPCA) published a clinical practice update to detect, evaluate, and manage pediatric dyslipidemia. However, guidance on its translation into clinical laboratories is lacking. The Canadian Society of Clinical Chemists Working Group on Reference Interval Harmonization Lipid Team aims to assist guideline implementation and promote harmonized pediatric lipid reporting across Canada. The 2022 CCS/CPCA clinical practice update, 2011 National Heart, Lung, and Blood Institute integrated guidelines, and new data analysis (Canadian pediatric reference values from the Canadian Laboratory Initiative on Pediatric Reference Intervals [CALIPER] and retrospective patient data from large community laboratories) were incorporated to develop 5 key recommendations. These include recommendations to: (1) offer nonfasting and fasting lipid testing; (2) offer a lipid panel including total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and triglycerides, with apolipoprotein B and lipoprotein(a) available as individually orderable tests; (3) flag total cholesterol, LDL-C, and non-HDL-C results ≥ 95th percentile, and HDL-C results < 10th percentile, as recommended by CCS/CPCA/National Heart, Lung, and Blood Institute and validated by CALIPER, and flag apolipoprotein B and nonfasting triglyceride results ≥ 95th percentile on the basis of CALIPER, and do not flag Lp(a) results but mention the adult cutoff in the interpretive comments; (4) implement interpretive comments listed in the current report; and (5) implement the National Institutes of Health LDL-C equation. The Canadian Society of Clinical Chemists Working Group on Reference Interval Harmonization Lipid Team will support clinical laboratories to implement these recommendations using knowledge translation strategies. Harmonizing pediatric lipid reporting across Canadian clinical laboratories will optimize clinical decision-making and improve cardiovascular risk management in youth.

A cloud-based medical device for predicting cardiac risk in suspected coronary artery disease: a rapid review and conceptual economic model

Background

The CaRi-Heart® device estimates risk of 8-year cardiac death, using a prognostic model, which includes perivascular fat attenuation index, atherosclerotic plaque burden and clinical risk factors.

Objectives

To provide an Early Value Assessment of the potential of CaRi-Heart Risk to be an effective and cost-effective adjunctive investigation for assessment of cardiac risk, in people with stable chest pain/suspected coronary artery disease, undergoing computed tomography coronary angiography. This assessment includes conceptual modelling which explores the structure and evidence about parameters required for model development, but not development of a full executable cost-effectiveness model.

Data sources

Twenty-four databases, including MEDLINE, MEDLINE In-Process and EMBASE, were searched from inception to October 2022.

Methods

Review methods followed published guidelines. Study quality was assessed using Prediction model Risk Of Bias ASsessment Tool. Results were summarised by research question: prognostic performance; prevalence of risk categories; clinical effects; costs of CaRi-Heart. Exploratory searches were conducted to inform conceptual cost-effectiveness modelling.

Results

The only included study indicated that CaRi-Heart Risk may be predictive of 8 years cardiac death. The hazard ratio, per unit increase in CaRi-Heart Risk, adjusted for smoking, hypercholesterolaemia, hypertension, diabetes mellitus, Duke index, presence of high-risk plaque features and epicardial adipose tissue volume, was 1.04 (95% confidence interval 1.03 to 1.06) in the model validation cohort. Based on Prediction model Risk Of Bias ASsessment Tool, this study was rated as having high risk of bias and high concerns regarding its applicability to the decision problem specified for this Early Value Assessment. We did not identify any studies that reported information about the clinical effects or costs of using CaRi-Heart to assess cardiac risk. Exploratory searches, conducted to inform the conceptual cost-effectiveness modelling, indicated that there is a deficiency with respect to evidence about the effects of changing existing treatments or introducing new treatments, based on assessment of cardiac risk (by any method), or on measures of vascular inflammation (e.g. fat attenuation index). A de novo conceptual decision-analytic model that could be used to inform an early assessment of the cost effectiveness of CaRi-Heart is described. A combination of a short-term diagnostic model component and a long-term model component that evaluates the downstream consequences is anticipated to capture the diagnosis and the progression of coronary artery disease.

Limitations

The rapid review methods and pragmatic additional searches used to inform this Early Value Assessment mean that, although areas of potential uncertainty have been described, we cannot definitively state where there are evidence gaps.

Conclusions

The evidence about the clinical utility of CaRi-Heart Risk is underdeveloped and has considerable limitations, both in terms of risk of bias and applicability to United Kingdom clinical practice. There is some evidence that CaRi-Heart Risk may be predictive of 8-year risk of cardiac death, for patients undergoing computed tomography coronary angiography for suspected coronary artery disease. However, whether and to what extent CaRi-Heart represents an improvement relative to current standard of care remains uncertain. The evaluation of the CaRi-Heart device is ongoing and currently available data are insufficient to fully inform the cost-effectiveness modelling.

Future work

A large (n = 15,000) ongoing study, NCT05169333, the Oxford risk factors and non-invasive imaging study, with an estimated completion date of February 2030, may address some of the uncertainties identified in this Early Value Assessment.

Study registration

This study is registered as PROSPERO CRD42022366496.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR award ref: NIHR135672) and is published in full in Health Technology Assessment; Vol. 28, No. 31. See the NIHR Funding and Awards website for further award information.

First Iranian guidelines for the diagnosis, management, and treatment of hyperlipidemia in adults

This guideline is the first Iranian guideline developed for the diagnosis, management, and treatment of hyperlipidemia in adults. The members of the guideline developing group (GDG) selected 9 relevant clinical questions and provided recommendations or suggestions to answer them based on the latest scientific evidence. Recommendations include the low-density lipoprotein cholesterol (LDL-C) threshold for starting drug treatment in adults lacking comorbidities was determined to be over 190 mg/dL and the triglyceride (TG) threshold had to be >500 mg/dl. In addition to perform fasting lipid profile tests at the beginning and continuation of treatment, while it was suggested to perform cardiovascular diseases (CVDs) risk assessment using valid Iranian models. Some recommendations were also provided on lifestyle modification as the first therapeutic intervention. Statins were recommended as the first line of drug treatment to reduce LDL-C, and if its level was high despite the maximum allowed or maximum tolerated drug treatment, combined treatment with ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors, or bile acid sequestrants was suggested. In adults with hypertriglyceridemia, pharmacotherapy with statin or fibrate was recommended. The target of drug therapy in adults with increased LDL-C without comorbidities and risk factors was considered an LDL-C level of <130 mg/dl, and in adults with increased TG without comorbidities and risk factors, TG levels of <200 mg/dl. In this guideline, specific recommendations and suggestions were provided for the subgroups of the general population, such as those with CVD, stroke, diabetes, chronic kidney disease, elderly, and women.

Feasibility of postprandial optical scattering of lipoproteins in blood as an optical marker of cardiovascular disease risk: modeling and experimental validation

Significance

Blood lipid levels (i.e., triglycerides (TGs) and cholesterol) are a strong predictor of cardiovascular disease (CVD) risk. Current methods for measuring blood lipids require invasive blood draws and traditional lab testing, limiting their practicality for frequent monitoring. Optical measurements of lipoproteins, which carry TG and cholesterol in blood, may lead to simpler invasive or non-invasive methods for more frequent and rapid blood lipid measurements.

Aim

To investigate the effect of lipoproteins on optical properties of blood before and after a high-fat meal (i.e., the pre- and post-prandial state).

Approach

Simulations were performed using Mie theory to estimate lipoprotein scattering properties. A literature review was conducted to identify key simulation parameters including lipoprotein size distributions and number density. Experimental validation of ex-vivo blood samples was conducted using spatial frequency domain imaging.

Results

Our results indicated that lipoproteins in blood, particularly very low-density lipoproteins and chylomicrons, are highly scattering in the visible and near-infrared wavelength region. Estimates of the increase in the reduced scattering coefficient (μ s ' ) of blood at 730 nm after a high-fat meal ranged from 4% for a healthy individual, to 15% for those with type 2 diabetes, to up to 64% for those suffering from hypertriglyceridemia. A reduction in blood scattering anisotropy (g ) also occurred as a function of TG concentration increase.

Conclusion

These findings lay the foundation for future research in the development of optical methods for invasive and non-invasive optical measure of blood lipoproteins, which could improve early detection and management of CVD risk.

Long-term monitoring in primary care for chronic kidney disease and chronic heart failure: a multi-method research programme

Background

Long-term monitoring is important in chronic condition management. Despite considerable costs of monitoring, there is no or poor evidence on how, what and when to monitor. The aim of this study was to improve understanding, methods, evidence base and practice of clinical monitoring in primary care, focusing on two areas: chronic kidney disease and chronic heart failure.

Objectives

The research questions were as follows: does the choice of test affect better care while being affordable to the NHS? Can the number of tests used to manage individuals with early-stage kidney disease, and hence the costs, be reduced? Is it possible to monitor heart failure using a simple blood test? Can this be done using a rapid test in a general practitioner consultation? Would changes in the management of these conditions be acceptable to patients and carers?

Design

Various study designs were employed, including cohort, feasibility study, Clinical Practice Research Datalink analysis, seven systematic reviews, two qualitative studies, one cost-effectiveness analysis and one cost recommendation.

Setting

This study was set in UK primary care.

Data sources

Data were collected from study participants and sourced from UK general practice and hospital electronic health records, and worldwide literature.

Participants

The participants were NHS patients (Clinical Practice Research Datalink: 4.5 million patients), chronic kidney disease and chronic heart failure patients managed in primary care (including 750 participants in the cohort study) and primary care health professionals.

Interventions

The interventions were monitoring with blood and urine tests (for chronic kidney disease) and monitoring with blood tests and weight measurement (for chronic heart failure).

Main outcome measures

The main outcomes were the frequency, accuracy, utility, acceptability, costs and cost-effectiveness of monitoring.

Results

Chronic kidney disease: serum creatinine testing has increased steadily since 1997, with most results being normal (83% in 2013). Increases in tests of creatinine and proteinuria correspond to their introduction as indicators in the Quality and Outcomes Framework. The Chronic Kidney Disease Epidemiology Collaboration equation had 2.7% greater accuracy (95% confidence interval 1.6% to 3.8%) than the Modification of Diet in Renal Disease equation for estimating glomerular filtration rate. Estimated annual transition rates to the next chronic kidney disease stage are ≈ 2% for people with normal urine albumin, 3–5% for people with microalbuminuria (3–30 mg/mmol) and 3–12% for people with macroalbuminuria (> 30 mg/mmol). Variability in estimated glomerular filtration rate-creatinine leads to misclassification of chronic kidney disease stage in 12–15% of tests in primary care. Glycaemic-control and lipid-modifying drugs are associated with a 6% (95% confidence interval 2% to 10%) and 4% (95% confidence interval 0% to 8%) improvement in renal function, respectively. Neither estimated glomerular filtration rate-creatinine nor estimated glomerular filtration rate-Cystatin C have utility in predicting rate of kidney function change. Patients viewed phrases such as ‘kidney damage’ or ‘kidney failure’ as frightening, and the term ‘chronic’ was misinterpreted as serious. Diagnosis of asymptomatic conditions (chronic kidney disease) was difficult to understand, and primary care professionals often did not use ‘chronic kidney disease’ when managing patients at early stages. General practitioners relied on Clinical Commissioning Group or Quality and Outcomes Framework alerts rather than National Institute for Health and Care Excellence guidance for information. Cost-effectiveness modelling did not demonstrate a tangible benefit of monitoring kidney function to guide preventative treatments, except for individuals with an estimated glomerular filtration rate of 60–90 ml/minute/1.73 m2, aged < 70 years and without cardiovascular disease, where monitoring every 3–4 years to guide cardiovascular prevention may be cost-effective. Chronic heart failure: natriuretic peptide-guided treatment could reduce all-cause mortality by 13% and heart failure admission by 20%. Implementing natriuretic peptide-guided treatment is likely to require predefined protocols, stringent natriuretic peptide targets, relative targets and being located in a specialist heart failure setting. Remote monitoring can reduce all-cause mortality and heart failure hospitalisation, and could improve quality of life. Diagnostic accuracy of point-of-care N-terminal prohormone of B-type natriuretic peptide (sensitivity, 0.99; specificity, 0.60) was better than point-of-care B-type natriuretic peptide (sensitivity, 0.95; specificity, 0.57). Within-person variation estimates for B-type natriuretic peptide and weight were as follows: coefficient of variation, 46% and coefficient of variation, 1.2%, respectively. Point-of-care N-terminal prohormone of B-type natriuretic peptide within-person variability over 12 months was 881 pg/ml (95% confidence interval 380 to 1382 pg/ml), whereas between-person variability was 1972 pg/ml (95% confidence interval 1525 to 2791 pg/ml). For individuals, monitoring provided reassurance; future changes, such as increased testing, would be acceptable. Point-of-care testing in general practice surgeries was perceived positively, reducing waiting time and anxiety. Community heart failure nurses had greater knowledge of National Institute for Health and Care Excellence guidance than general practitioners and practice nurses. Health-care professionals believed that the cost of natriuretic peptide tests in routine monitoring would outweigh potential benefits. The review of cost-effectiveness studies suggests that natriuretic peptide-guided treatment is cost-effective in specialist settings, but with no evidence for its value in primary care settings.

Limitations

No randomised controlled trial evidence was generated. The pathways to the benefit of monitoring chronic kidney disease were unclear.

Conclusions

It is difficult to ascribe quantifiable benefits to monitoring chronic kidney disease, because monitoring is unlikely to change treatment, especially in chronic kidney disease stages G3 and G4. New approaches to monitoring chronic heart failure, such as point-of-care natriuretic peptide tests in general practice, show promise if high within-test variability can be overcome.

Future work

The following future work is recommended: improve general practitioner–patient communication of early-stage renal function decline, and identify strategies to reduce the variability of natriuretic peptide.

Study registration

This study is registered as PROSPERO CRD42015017501, CRD42019134922 and CRD42016046902.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 10. See the NIHR Journals Library website for further project information.

Cost-effectiveness analysis for HbA1c test intervals to screen patients with type 2 diabetes based on risk stratification

BACKGROUND

The best HbA1c test interval strategy for detecting new type 2 diabetes mellitus (T2DM) cases in healthy individuals should be determined with consideration of HbA1c test characteristics, risk stratification towards T2DM and cost effectiveness.

METHODS

State transition models were constructed to investigate the optimal screening interval for new cases of T2DM among each age- and BMI-stratified health individuals. Age was stratified into 30-44-, 45-59-, and 60-74-year-old age groups, and BMI was also stratified into underweight, normal, overweight and obesity. In each model, different HbA1c test intervals were evaluated with respect to the incremental cost-effectiveness ratio (ICER) and costs per quality-adjusted life year (QALY). Annual intervals (Japanese current strategy), every 3 years (recommendations in US and UK) and intervals which are tailored to each risk stratification group were compared. All model parameters, including costs for screening and treatment, rates for complications and mortality and utilities, were taken from published studies. The willingness-to-pay threshold in the cost-effectiveness analysis was set to US $50,000/QALY.

RESULTS

The HbA1c test interval for detecting T2DM in healthy individuals varies by age and BMI. Three-year intervals were the most cost effective in obesity at all ages-30-44: $15,034/QALY, 45-59: $11,849/QALY, 60-74: $8685/QALY-compared with the other two interval strategies. The three-year interval was also the most cost effective in the 60-74-year-old age groups-underweight: $11,377/QALY, normal: $18,123/QALY, overweight: $12,537/QALY-and in the overweight 45-59-year-old group; $18,918/QALY. In other groups, the screening interval for detecting T2DM was found to be longer than 3 years, as previously reported. Annual screenings were dominated in many groups with low BMI and in younger age groups. Based on the probability distribution of the ICER, results were consistent among any groups.

CONCLUSIONS

The three-year screening interval was optimal among elderly at all ages, the obesity at all ages and the overweight in 45-59-year-old group. For those sin the low-BMI and younger age groups, the optimal HbA1c test interval could be longer than 3 years. Annual screening to detect T2DM was not cost effective and should not be applied in any population.

2021 Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in Adults

The 2021 guidelines primary panel selected clinically relevant questions and produced updated recommendations, on the basis of important new findings that have emerged since the 2016 guidelines. In patients with clinical atherosclerosis, abdominal aortic aneurysm, most patients with diabetes or chronic kidney disease, and those with low-density lipoprotein cholesterol ≥ 5 mmol/L, statin therapy continues to be recommended. We have introduced the concept of lipid/lipoprotein treatment thresholds for intensifying lipid-lowering therapy with nonstatin agents, and have identified the secondary prevention patients who have been shown to derive the largest benefit from intensification of therapy with these agents. For all other patients, we emphasize risk assessment linked to lipid/lipoprotein evaluation to optimize clinical decision-making. Lipoprotein(a) measurement is now recommended once in a patient's lifetime, as part of initial lipid screening to assess cardiovascular risk. For any patient with triglycerides ˃ 1.5 mmol/L, either non-high-density lipoprotein cholesterol or apolipoprotein B are the preferred lipid parameter for screening, rather than low-density lipoprotein cholesterol. We provide updated recommendations regarding the role of coronary artery calcium scoring as a clinical decision tool to aid the decision to initiate statin therapy. There are new recommendations on the preventative care of women with hypertensive disorders of pregnancy. Health behaviour modification, including regular exercise and a heart-healthy diet, remain the cornerstone of cardiovascular disease prevention. These guidelines are intended to provide a platform for meaningful conversation and shared-decision making between patient and care provider, so that individual decisions can be made for risk screening, assessment, and treatment.

Systematic review of clinical guidelines for lipid lowering in the secondary prevention of cardiovascular disease events

BACKGROUND

The WHO recommends that those with established cardiovascular disease should be treated with lipid-lowering therapy, but there is no specific guidance regarding lipid monitoring. Unnecessary general practitioner visits may be a burden for patients and increase healthcare costs. A systematic review of the current guidelines was performed to reveal gaps in the evidence base for optimal lipid monitoring approaches.

METHODS

For this systematic review, a search of Medline, Cumulative Index to Nursing and Allied Health Literature and Turning Research Into Practice databases was conducted for relevant guidelines published in the 10 years prior to 31 December 2019. Recommendations surrounding the frequency of testing, lipid-lowering therapies and target cholesterol values were compared qualitatively. Each guideline was assessed using the 2009 Appraisal of Guidelines for Research and Evaluation II tool.

RESULTS

Twenty-two guidelines were included. All recommended statins as the primary lipid-lowering therapy, with a high level of supporting evidence. Considerable variation was found in the recommendations for cholesterol targets. Seventeen guidelines provided at least one cholesterol target, which for low-density lipoprotein (LDL) cholesterol ranged between 1.0 and 2.6 mmol/L, although the most frequently recommended was <1.8 mmol/L (n=12). For long-term follow-up, many recommended reviewing patients annually (n=9), although there was some variation in recommendations for the interval of between 3 and 12 months. Supporting evidence for any approach was limited, often being derived from clinical opinion.

CONCLUSIONS

Further research is required to provide an evidence base for optimal lipid monitoring of the on-statin secondary prevention population.

Management of Dyslipidemia for Cardiovascular Disease Risk Reduction: Synopsis of the 2020 Updated U.S. Department of Veterans Affairs and U.S. Department of Defense Clinical Practice Guideline

DESCRIPTION

In June 2020, the U.S. Department of Veterans Affairs (VA) and U.S. Department of Defense (DoD) released a joint update of their clinical practice guideline for managing dyslipidemia to reduce cardiovascular disease risk in adults. This synopsis describes the major recommendations.

METHODS

On 6 August to 9 August 2019, the VA/DoD Evidence-Based Practice Work Group (EBPWG) convened a joint VA/DoD guideline development effort that included clinical stakeholders and conformed to the Institute of Medicine's tenets for trustworthy clinical practice guidelines. The guideline panel developed key questions, systematically searched and evaluated the literature (English-language publications from 1 December 2013 to 16 May 2019), and developed 27 recommendations and a simple 1-page algorithm. The recommendations were graded by using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

RECOMMENDATIONS

This synopsis summarizes key features of the guideline in 7 crucial areas: targeting of statin dose (not low-density lipoprotein cholesterol goals), additional tests for risk prediction, primary and secondary prevention, laboratory testing, physical activity, and nutrition.

The utility of long-term blood pressure variability for cardiovascular risk prediction in primary care

OBJECTIVES

Blood pressure (BP) is a long-established risk factor for cardiovascular disease (CVD). SBP is used in all widely used cardiovascular risk scores for clinical decision-making. Recently, within-person BP variability has been shown to be a major predictor of CVD. We investigated whether cardiovascular risk scores could be improved by incorporating BP variability with standard risk factors.

METHODS

We used cohort data on patients aged 40-74 on 1 January 2005, from English general practices contributing to the Clinical Practice Research Datalink, a research database derived from electronic health records. Data were linked to hospital episodes and mortality data. SBP variability independent of the mean was calculated across up to six clinic visits. We divided data geographically into derivation and validation data sets. In the derivation data set, we developed a reference model, incorporating risk factors used in previous scores and an index model, incorporating the same factors and BP variability. We calculated model validation statistics in the validation data set including calibration ratio and c-statistic.

RESULTS

In the derivation data set, BP variability was associated with CVD, independently of other risk factors (P = 0.005). However, in the validation data set, both models had similar c-statistic (0.7415 and 0.7419, respectively), R (31.8 and 32.0, respectively) and calibration ratio (0.938 and 0.940, respectively).

CONCLUSION

The association of BP variability with CVD is statistically significant in a large data set but does not substantially improve the performance of a cardiovascular risk score.

The Effect of Gluten-free Diet on Cardiovascular Risk Factors in Newly Diagnosed Pediatric Celiac Disease Patients

OBJECTIVES

Although gluten-free diet (GFD) is the only proven therapy for celiac disease (CD), its effect on cardiovascular disease (CVD) risk factors is still unclear. Our aim was to determine whether adherence to GFD affects CVD risk factors among newly diagnosed pediatric CD subjects.

METHODS

We prospectively enrolled pediatric subjects undergoing upper gastrointestinal endoscopy for suspected CD. We collected anthropometric and laboratory parameters related to CVD risk factors at the time of CD diagnosis and 1 year after initiation of a GFD and evaluated changes in CVD risk factors. Paired t tests or Wilcoxon nonparametric tests were used, each when appropriate.

RESULTS

One hundred ten newly diagnosed CD pediatric subjects were included in the analysis. There were 64 (58.2%) girls and the mean age at diagnosis was 6.8 ± 3.4 years. Median body mass index z scores (P = 0.84), rates of underweight or overweight (P = 0.32), and rates of elevated blood pressure (P = 0.78) remained unchanged. Although median fasting insulin levels increased (1.9 vs 5.4 μU/mL, P < 0.001), insulin resistance as measured by homeostatic model assessment did not increase after 1 year of GFD (P = 0.16). Although rates of dyslipidemia remained unchanged, median high-density lipoprotein levels increased on GFD (47 vs 51 mg/dL, P < 0.001).

CONCLUSIONS

In this pediatric CD cohort, GFD for 1 year was not associated with increased CVD risk factors. The long-term significance of these mild changes is yet to be determined.

Health Economic Evaluations of Digital Health Interventions for Secondary Prevention in Stroke Patients: A Systematic Review

BACKGROUND

In the first 5 years after their stroke, about a quarter of patients will suffer from a recurrent stroke. Digital health interventions facilitating interactions between a caregiver and a patient from a distance are a promising approach to improve patient adherence to lifestyle changes proposed by secondary prevention guidelines. Many of these interventions are not implemented in daily practice, even though efficacy has been shown. One of the reasons can be the lack of clear economic incentives for implementation. We propose to map all health economic evidence regarding digital health interventions for secondary stroke prevention.

SUMMARY

We performed a systematic search according to PRISMA-P guidelines and searched on PubMed, Web of Science, Cochrane, and National Institute for Health Research Economic Evaluation Database. Only digital health interventions for secondary prevention in stroke patients were included and all study designs and health economic outcomes were accepted. We combined the terms "Stroke OR Cardiovascular," "Secondary prevention," "Digital health interventions," and "Cost" in one search string using the AND operator. The search performed on April 20, 2017 yielded 163 records of which 26 duplicates were removed. After abstract screening, 20 articles were retained for full-text analysis, of which none reported any health economic evidence that could be included for analysis or discussion. Key Messages: There is a lack of evidence on health economic outcomes on digital health interventions for secondary stroke prevention. Future research in this area should take health economics into consideration when designing a trial and there is a clear need for health economic evidence and models.

Evaluation of clarity of presentation and applicability of monitoring instructions for patients using lithium in clinical practice guidelines for treatment of bipolar disorder

OBJECTIVES

Clinical practice guidelines (CPGs) for treatment of bipolar disorder (BD) aim to provide guidance to health care professionals on monitoring of patients using lithium. The aim was to assess the clarity of presentation and applicability of monitoring instructions for patients using lithium in CPGs for treatment of BD.

METHODS

CPGs for treatment of BD were selected from acknowledged professional organizations from multiple continents. CPGs were rated on the clarity of presentation and applicability of lithium monitoring instructions using the Appraisal of Guidelines Research and Evaluation (AGREE) II tool. The applicability of monitoring instructions was assessed according to the Systematic Information for Monitoring (SIM) score. Monitoring instructions were considered applicable when a SIM score of ≥3 was found.

RESULTS

The clarity of presentation for six out of the nine CPGs was good (>70%) using the AGREE II tool. Only one CPG scored >70% on applicability. Descriptions of the resource implications and facilitators of and barriers to monitoring were most often missing. All CPGs contained instructions for monitoring of lithium serum levels and renal and thyroid function. Information provided in monitoring instructions (n = 247) was in general applicable to clinical practice (77%) based on the SIM score. Overall, a median SIM score of 3 (interquartile range 3-4) was found.

CONCLUSIONS

Improvement of the applicability of CPGs is recommended, and can be achieved by describing the resource implications and facilitators of and barriers to monitoring. In addition, information on critical values and instructions on how to respond to aberrant monitoring parameters are needed. With such improvements, CPGs may better aid health care professionals to monitor patients using lithium.

Ten-second central SBP variability predicts first and recurrent cardiovascular events

OBJECTIVE

Long-term (day-to-day or visit-to-visit) blood pressure variability (BPV) predicts elevated risk of cardiovascular events but represents just one BPV type. We examined whether 10-s BPV predicts cardiovascular events.

METHODS

In 4999 adults (58% men; aged 50-84 years; 670 with a prior cardiovascular event), we performed suprasystolic brachial pressure measurements over ∼10 s, yielding aortic pressure waveforms. BPV was calculated by average real variability (ARV), root mean square of successive differences, standard deviation (SD), coefficient of variation and relative range. Participants were followed up for 4.6 years (median), accruing 310 first and 187 recurrent cardiovascular events, respectively.

RESULTS

In multivariable-adjusted analyses, all central SBPV parameters were associated with first cardiovascular events: the standardized hazard ratio for each ranged from 1.25 to 1.29. The hazard ratio between the lowest and highest sextile ranged from 1.92 [95% confidence interval (CI) 1.31-2.80] for coefficient of variation to 2.19 (95% CI 1.38-3.46) for ARV. All central SBPV parameters also were associated with higher risk of recurrent cardiovascular events: adjusted standardized hazard ratio ranged from 1.16 to 1.21. Because of fewer recurrent events, these low-versus-high comparisons were based on tertiles; hazard ratios between the lowest and highest tertiles ranged from 1.50 (95% CI 1.02-2.23) for ARV to 1.76 (95% CI 1.20-2.60) for SD. The highest categorical net reclassification improvement for 5-year risk of first cardiovascular events was 13% (95% CI 7-18%) and substantially higher among those with intermediate (10-20%) risk: 39% (95% CI 26-52%).

CONCLUSION

Ten-second central SBPV parameters predict first and recurrent cardiovascular events.

The Role of Measurement Uncertainty in Health Technology Assessments (HTAs) of In Vitro Tests

INTRODUCTION

Numerous factors contribute to uncertainty in test measurement procedures, and this uncertainty can have a significant impact on the downstream clinical utility and cost-effectiveness of testing strategies. Currently, however, there is no clear guidance concerning if or how such factors should be considered within Health Technology Assessments (HTAs) of tests.

OBJECTIVE

The aim was to provide an introduction to key concepts in measurement uncertainty for the HTA community and to explore, via systematic review, current methods utilised within HTAs.

METHODS

HTAs of in vitro tests including a model-based economic evaluation were identified via the Centre for Reviews and Dissemination (CRD) HTA database and key reimbursement authority websites. Data were extracted to explore the specific components of measurement uncertainty assessed and methods utilised. The findings were narratively synthesised.

RESULTS

Of 107 identified HTAs, 20 (19%) attempted to assess components of measurement uncertainty: 15 did so via some form of pre-model assessment (such as a literature review or laboratory survey); four also included components within the economic model; and one considered measurement uncertainty within the model only. One study quantified the impact of measurement uncertainty on cost-effectiveness and found that this parameter significantly changed the results, but did not impact the overall decision uncertainty.

CONCLUSION

A minority of HTAs identified from this review used various approaches to assess and/or incorporate the impact of measurement uncertainty, indicating that these assessments are feasible. Uncertainty remains around best practice methodology for conducting such analyses; further research is required to ensure that future HTAs are fit for purpose.

Effect of blood pressure and total cholesterol measurement on risk prediction using the Systematic COronary Risk Evaluation (SCORE)

BACKGROUND

To compare the reproducibility in total cholesterol (TC), systolic blood pressure (BP), and the resulting Systematic COronary Risk Evaluation (SCORE) obtained by an in-office cardio-preventive screening program (SP) and a subsequent program performed in a clinical trial examination center (EP).

METHODS

A total of 307 individuals (60.3% female, mean age = 52.8 years) participated. According to TC and BP measurements at the SP and EP, three variables were created: the SCORE^SP = single BP reading at the SP, the SCORE^EP/BP-first = first BP reading at the EP, and the SCORE^EP/BP-mean = mean second/third BP reading at the EP. Differences in TC and BP were analyzed. Associations between age, sex and mean differences between the SCORE^SP and the SCORE^EP/BP-first (M1) and the SCORE^EP/BP-mean (M2) were analyzed using multivariable linear and quantile regression.

RESULTS

TC and BP values from the SP were significantly higher than those from the EP. Among individuals with a decreased SCORE value at the EP (compared to the SP), younger age was associated with a higher improvement in risk estimation compared with older age. Female sex was associated with higher risk improvement in the SCORE between the SP and the EP compared with male sex. Associations between both demographics and M1 (M2) achieved statistical significance at the 75.0th (50th) percentile.

CONCLUSIONS

The reproducibility of results in cardiovascular risk prediction seems to be influenced by the accuracy of BP measurement. It seems that younger individuals and females are more likely to benefit from accuracy compared with older individuals and males.

Patterns and trends of potentially inappropriate high-density lipoprotein cholesterol testing in Australian adults at high risk of cardiovascular disease from 2008 to 2014: analysis of linked individual patient data from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme

OBJECTIVES

We examine the extent to which the adult Australian population on lipid-lowering medications receives the level of high-density lipoprotein cholesterol (HDL-C) testing recommended by national guidelines.

DATA

We analysed records from 7 years (2008-2014) of the 10% publicly available sample of deidentified, individual level, linked Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) electronic databases of Australia.

METHODS

The PBS data were used to identify individuals on stable prescriptions of lipid-lowering treatment. The MBS data were used to estimate the annual frequency of HDL-C testing. We developed a methodology to address the issue of 'episode coning' in the MBS data, which causes an undercounting of pathology tests. We used a published figure on the proportion of unreported HDL-C tests to correct for the undercounting and estimate the probability that an HDL-C test was performed. We judged appropriateness of testing frequency by comparing the HDL-C testing rate to guidelines' recommendations of annual testing for people at high risk for cardiovascular disease.

RESULTS

We estimated that approximately 49% of the population on stable lipid-lowering treatment did not receive any HDL-C test in a given year. We also found that approximately 19% of the same population received two or more HDL-C tests within the year. These levels of underutilisation and overutilisation have been changing at an average rate of 2% and -4% a year, respectively, since 2009. The yearly expenditure associated with test overutilisation was approximately $A4.3 million during the study period, while the cost averted because of test underutilisation was approximately $A11.3 million a year.

CONCLUSIONS

We found that approximately half of Australians on stable lipid-lowering treatment may be having fewer HDL-C testing than recommended by national guidelines, while nearly one-fifth are having more tests than recommended.

HbA1c monitoring interval in patients on treatment for stable type 2 diabetes. A ten-year retrospective, open cohort study

[Aims] This study aims to suggest an informative interval for HbA1c in DM patients with stable glycemic control, based on test characteristics of the HbA1C assay using the signal-to-noise ratio method. [Methods] This was a retrospective, open cohort study. Data were collected between January 2005 to December 2014 at a tertiary-level community hospital in Japan. All adult patients aged under 75 years, with stable glycemic control on a first pharmaceutical regimen for Type II diabetes, and at least two HbA1c measurements after they achieved glycemic stability, were included in the analysis. We defined stable glycemic control as HbA1c <7.0% (52 mmol/mol) and requiring no change in the medication regimen after three consecutive measurements. We adapted a signal-to-noise method for distinguishing true change from measurement error by constructing a linear random effects model to calculate signal and noise for HbA1c. The screening interval for HbA1c was defined as informative when the signal-to-noise ratio exceeded 1. [Results] Among 1066 adults with diabetes, 639 patients (18.5%) were identified as achieving stable glycemic control (511 male (67.3%)), with a mean HbA1c (SD) of 6.4 (0.4)% (46 mmol/mol). Patients with stable glycemic control increase their HbA1c 0.27% (3 mmol/mol) every year while HbA1c has 0.32% (3.5 mmol/mol) noise, as testing characteristics. Signal exceeds noise after 1.2 years (95%CI: 0.9-1.6). [Conclusion] Once patients achieve stable glycemic control at their HbA1c goal, an informative interval for HbA1c monitoring is once every year. Current guidelines, which suggest testing every six months, may contribute to substantial over-testing.

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.

Overview of guidelines for the management of dyslipidemia: EU perspectives

Modern medicine is characterized by a continuous genesis of evidence making it very difficult to translate the latest findings into a better clinical practice. Clinical practice guidelines (CPG) emerge to provide clinicians evidence-based recommendations for their daily clinical practice. However, the high number of existing CPG as well as the usual differences in the given recommendations usually increases the clinician’s confusion and doubts. It has apparently been the case for the 2013 American College of Cardiology/American Heart Association (ACC/AHA) Guideline on the Treatment of Blood Cholesterol. These CPG proposed new and controversial concepts that have usually been considered an antagonist shift respective to European CPG. The most controversial published proposals are: 1) to consider evidence just from randomized clinical trials, 2) creation of a new cardiovascular (CV) risk calculator, 3) to consider reducing CV risk instead of reducing low-density lipoprotein cholesterol (LDLc) as the target of the treatment, and 4) consideration of statins as the only drugs for treatment. A deep analysis of the 2013 American College of Cardiology/American Heart Association CPG and comparison with the European ones show that from a practical and clinical point of view, there are more similarities than differences. To further help clinicians in their daily work, in the present globalized world, it is time to discuss and adopt a mutually agreed upon document created by both sides of the Atlantic. Probably it is not a short-term solution. Meanwhile, taking advantage of the similarities, the recommended practical attitude for the daily clinical practice should be based on 1) early detection of people with increased CV risk promoting the use of validated local scales, 2) reinforce the mainstream importance of nonpharmacological treatment, and 3) need for periodically monitoring response with analytical parameters (LDL or non-high-density lipoprotein cholesterol) and global CV risk estimation. Technological solutions such as the big data technology could help to obtain high-quality evidence in an intermediate term.

Blood pressure variability and cardiovascular disease: systematic review and meta-analysis

OBJECTIVE

 To systematically review studies quantifying the associations of long term (clinic), mid-term (home), and short term (ambulatory) variability in blood pressure, independent of mean blood pressure, with cardiovascular disease events and mortality.

DATA SOURCES

 Medline, Embase, Cinahl, and Web of Science, searched to 15 February 2016 for full text articles in English.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

 Prospective cohort studies or clinical trials in adults, except those in patients receiving haemodialysis, where the condition may directly impact blood pressure variability. Standardised hazard ratios were extracted and, if there was little risk of confounding, combined using random effects meta-analysis in main analyses. Outcomes included all cause and cardiovascular disease mortality and cardiovascular disease events. Measures of variability included standard deviation, coefficient of variation, variation independent of mean, and average real variability, but not night dipping or day-night variation.

RESULTS

 41 papers representing 19 observational cohort studies and 17 clinical trial cohorts, comprising 46 separate analyses were identified. Long term variability in blood pressure was studied in 24 papers, mid-term in four, and short-term in 15 (two studied both long term and short term variability). Results from 23 analyses were excluded from main analyses owing to high risks of confounding. Increased long term variability in systolic blood pressure was associated with risk of all cause mortality (hazard ratio 1.15, 95% confidence interval 1.09 to 1.22), cardiovascular disease mortality (1.18, 1.09 to 1.28), cardiovascular disease events (1.18, 1.07 to 1.30), coronary heart disease (1.10, 1.04 to 1.16), and stroke (1.15, 1.04 to 1.27). Increased mid-term and short term variability in daytime systolic blood pressure were also associated with all cause mortality (1.15, 1.06 to 1.26 and 1.10, 1.04 to 1.16, respectively).

CONCLUSIONS

 Long term variability in blood pressure is associated with cardiovascular and mortality outcomes, over and above the effect of mean blood pressure. Associations are similar in magnitude to those of cholesterol measures with cardiovascular disease. Limited data for mid-term and short term variability showed similar associations. Future work should focus on the clinical implications of assessment of variability in blood pressure and avoid the common confounding pitfalls observed to date.

SYSTEMATIC REVIEW REGISTRATION

 PROSPERO CRD42014015695.