Are preventive drugs preventive enough? A study of patients' expectation of benefit from preventive drugs

Reporting of absolute and relative risk measures in oral health and cardiovascular events studies: A systematic review

OBJECTIVES

To understand the magnitude of risk of health events, such as cardiovascular diseases (CVD), related to poor oral health, both relative and absolute risk measures should be reported. Our aim was to investigate the extent to which absolute and relative measures of risk are reported in longitudinal studies that assess the association between oral health indicators (OHIs) and CVD.

METHODS

A systematic search of longitudinal studies investigating the association of any OHI with CVD was carried out using the Embase, Medline and Cochrane library databases. The search covered each database from its inception date to August 2021. Data about reporting relative and absolute risks of the relationship between CVD and OHI from the abstract were extracted. If the relative risk for OHIs and CVD was reported in the abstract, then the underlying absolute risks were searched from the full text, and it was assessed whether it was similarly adjusted for confounding than was the relative risk in the abstract.

RESULTS

One hundred-six articles were included. From these, 85 (80%) studies reported the association of OHIs and CVD with one or more relative risks in the abstract. Of those 85 studies, the underlying absolute risks were accessible or calculable from the abstract or full text of 60 studies. However, of these 60 studies, in only 10 (12%), the underlying absolute risks were similarly adjusted, as were the relative risks in the abstract. The absolute risks of CVD by OHIs were rarely reported without corresponding relative risks in the abstract (n = 2, 2%). Median absolute risk difference in the CVD risk between exposure levels to which the first relative risk in the abstract referred was 1.8% (interquartile range 0.6-4.6, n = 63).

CONCLUSIONS

Focusing on relative risks over absolute risks was a common practice in literature. Reporting similarly adjusted underlying absolute risks of relative risks was rare in most studies, despite those being helpful for comprehending the magnitude of CVD-risk increase related to poor oral health. Current reporting practices could lead to an overinterpretation of risk increase of CVD related to poor oral health.

Prolongation of disease-free life: When is the benefit sufficient to warrant the effort of taking a preventive medicine?

The prolongation of disease-free life (PODL) required by people to be willing to accept an offer of a preventive treatment is unknown. Quantifying the required benefits could guide information and discussions about preventive treatment. In this study, we investigated how large the benefit in prolongation of a disease-free life (PODL) should be for individuals aged 50-80 years to accept a preventive treatment offer. We used a cross-sectional survey design based on a representative sample of 6847 Danish citizens aged 50-80 years. Data were collected in 2019 through a web-based standardized questionnaire administered by Statistics Denmark, and socio-demographic data were added from a national registry. We analyzed the data with chi-square tests and stepwise multinomial logistic regression. The results indicate that the required minimum benefit from the preventive treatment varied widely between individuals (1-week PODL = 14.8%, ≥4 years PODL = 39.2%), and that the majority of individuals (51.1%) required a PODL of ≥2 years. The multivariable analysis indicate that education and income were independently and negatively associated with requested minimum benefit, while age and smoking were independently and positively associated with requested minimum benefit to accept the preventive treatment. Most individuals aged 50-80 years required larger health benefits than most preventive medications on average can offer. The data support the need for educating patients and health care professionals on how to use average benefits when discussing treatment benefits, especially for primary prevention.

Communicating personalised statin therapy-effects as 10-year CVD-risk or CVD-free life-expectancy: does it improve decisional conflict? Three-armed, blinded, randomised controlled trial

OBJECTIVE

To determine whether communicating personalised statin therapy-effects obtained by prognostic algorithm leads to lower decisional conflict associated with statin use in patients with stable cardiovascular disease (CVD) compared with standard (non-personalised) therapy-effects.

DESIGN

Hypothesis-blinded, three-armed randomised controlled trial SETTING AND PARTICIPANTS: 303 statin users with stable CVD enrolled in a cohort INTERVENTION: Participants were randomised in a 1:1:1 ratio to standard practice (control-group) or one of two intervention arms. Intervention arms received standard practice plus (1) a personalised health profile, (2) educational videos and (3) a structured telephone consultation. Intervention arms received personalised estimates of prognostic changes associated with both discontinuation of current statin and intensification to the most potent statin type and dose (ie, atorvastatin 80 mg). Intervention arms differed in how these changes were expressed: either change in individual 10-year absolute CVD risk (iAR-group) or CVD-free life-expectancy (iLE-group) calculated with the SMART-REACH model (http://U-Prevent.com).

OUTCOME

Primary outcome was patient decisional conflict score (DCS) after 1 month. The score varies from 0 (no conflict) to 100 (high conflict). Secondary outcomes were collected at 1 or 6 months: DCS, quality of life, illness perception, patient activation, patient perception of statin efficacy and shared decision-making, self-reported statin adherence, understanding of statin-therapy, post-randomisation low-density lipoprotein cholesterol level and physician opinion of the intervention. Outcomes are reported as median (25th- 75th percentile).

RESULTS

Decisional conflict differed between the intervention arms: median control 27 (20-43), iAR-group 22 (11-30; p-value vs control 0.001) and iLE-group 25 (10-31; p-value vs control 0.021). No differences in secondary outcomes were observed.

CONCLUSION

In patients with clinically manifest CVD, providing personalised estimations of treatment-effects resulted in a small but significant decrease in decisional conflict after 1 month. The results support the use of personalised predictions for supporting decision-making.

TRIAL REGISTRATION

NTR6227/NL6080.

Increasing risk-concordant cardiovascular care in diverse health systems: a mixed methods pragmatic stepped wedge cluster randomized implementation trial of shared decision making (SDM4IP)

BACKGROUND

The primary prevention of cardiovascular (CV) events is often less intense in persons at higher CV risk and vice versa. Clinical practice guidelines recommend that clinicians and patients use shared decision making (SDM) to arrive at an effective and feasible prevention plan that is congruent with each person's CV risk and informed preferences. However, SDM does not routinely happen in practice. This study aims to integrate into routine care an SDM decision tool (CV PREVENTION CHOICE) at three diverse healthcare systems in the USA and study strategies that foster its adoption and routine use.

METHODS

This is a mixed method, hybrid type III stepped wedge cluster randomized study to estimate (a) the effectiveness of implementation strategies on SDM uptake and utilization and (b) the extent to which SDM results in prevention plans that are risk-congruent. Formative evaluation methods, including clinician and stakeholder interviews and surveys, will identify factors likely to impact feasibility, acceptability, and adoption of CV PREVENTION CHOICE as well as normalization of CV PREVENTION CHOICE in routine care. Implementation facilitation will be used to tailor implementation strategies to local needs, and implementation strategies will be systematically adjusted and tracked for assessment and refinement. Electronic health record data will be used to assess implementation and effectiveness outcomes, including CV PREVENTION CHOICE reach, adoption, implementation, maintenance, and effectiveness (measured as risk-concordant care plans). A sample of video-recorded clinical encounters and patient surveys will be used to assess fidelity. The study employs three theoretical approaches: a determinant framework that calls attention to categories of factors that may foster or inhibit implementation outcomes (the Consolidated Framework for Implementation Research), an implementation theory that guides explanation or understanding of causal influences on implementation outcomes (Normalization Process Theory), and an evaluation framework (RE-AIM).

DISCUSSION

By the project's end, we expect to have (a) identified the most effective implementation strategies to embed SDM in routine practice and (b) estimated the effectiveness of SDM to achieve feasible and risk-concordant CV prevention in primary care.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04450914 . Posted June 30, 2020 TRIAL STATUS: This study received ethics approval on April 17, 2020. The current trial protocol is version 2 (approved February 17, 2021). The first subject had not yet been enrolled at the time of submission.

Postponement of cardiovascular outcomes by statin use: A systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

To estimate the average outcome postponement (gain in days to an event) for cardiovascular outcomes in a meta-analysis of randomized, controlled statin trials, including any myocardial infarction, any stroke and cardiovascular death.

DESIGN

Systematic review of large randomized, placebo-controlled trials of statin use, including a random-effects meta-analysis of all included trials.

DATA SOURCES

We searched MEDLINE (15 July 2019) and ClinicalTrials.gov (16 October 2019).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomized, placebo-controlled trials of statin use that included at least 1000 participants. We identified 15 cardiovascular outcomes that were reported in more than 2 trials.

RESULTS

We included 19 trials. The summary outcome postponements for the 15 cardiovascular outcomes varied between -1 and 38 days. For four major outcomes, the summary outcome postponement in days was as follows: cardiovascular mortality, 9.27 days (95% CI: 3.6 to 14.91; I²  = 72%; 9 trials) non-vascular and non-cardiovascular mortality, 1.5 days (95% CI: -2.2 to 5.3; I²  = 0%; 6 trials) any myocardial infarction 18.0 days (95% CI; 12.1 to 24.1; I²  = 92%; 15 trials); and any stroke, 6.1 days (95% CI; 2.86 to 9.39; I²  = 66%; 14 trials).

CONCLUSION

Statin treatment provided a small, average postponement of cardiovascular outcomes during trial duration.

Chronic medication intake in patients with stable coronary heart disease across Europe: Evidence from the daily clinical practice. Results from the ESC EORP European Survey of Cardiovascular Disease Prevention and Diabetes (EUROASPIRE IV) Registry

BACKGROUND

As advised by the European guidelines on cardiovascular prevention, medication intake is a major component of secondary prevention. The aim of this study is to provide an in-depth overview of the medication intake in stable European coronary heart disease (CHD) patients.

METHODS

Analyses are based on the EUROASPIRE IV survey, including CHD patients (18 to 80 years) who were hospitalized for a coronary event. These patients were interviewed and examined 6 months to 3 years after their hospitalization. Information on cardiovascular medication intake is available for 7953 patients.

RESULTS

About 99.2% of patients were on any kind of cardiovascular medication and 67.6% of patients were taking at least 5 different cardiovascular drugs. Overall, even when patients are taking the recommended drug combination as advised by the European guidelines - accounting for their disease profile - a large proportion of patients is still not on blood pressure, LDL-C or HbA1c target. In addition, huge variations were seen in medication dose intake across countries. Comparing the dose intake to the defined daily dose (DDD as published by the WHO) indicated a substantial deviation from the DDDs for a large proportion of patients.

CONCLUSION

This study provides a unique overview of the cardiovascular medication intake in CHD patients. Overall, even when patients are taking the advised drug combination, a large proportion of patients is still not on risk factor target. Physicians should seek for a balance in medication intake and appropriate dose, accounting both for the benefits and risks of chronic drug intake.

Age-Related Medicine

A meeting organised by the Academy of Pharmaceutical Sciences focussed on the challenges of developing medicines for older adults. International experts discussed the complexity introduced by polypharmacy and multiple morbidities and how the risk⁻benefit ratio of a medicine changes as an individual ages. The way in which regulatory authorities are encouraging the development of age-appropriate medicines was highlighted. Examples were provided of the difficulties faced by the older population with some medicinal products and suggestions given as to how the pharmaceutical scientist can build the requirements of the older population into their development of new medicines, as well as improvements to existing ones.

Exclusively plant, whole-food diet for polypharmacy due to persistent atrial fibrillation, ischaemic cardiomyopathy, hyperlipidaemia and hypertension in an octogenarian

Polypharmacy is common and associated with negative health outcomes in the elderly. We report the case of an 82-year-old man with a history of polypharmacy due to coronary artery disease, myocardial infarction, ischaemic cardiomyopathy, hyperlipidaemia, hypertension and persistent atrial fibrillation who presented with memory loss, cognitive impairment, fatigue and weakness. His treatment plan included an exclusively plant, whole-food diet and moderate physical activity which resulted in a rapid reduction of hyperlipidaemia and high blood pressure and the discontinuation of statin, antihypertensive and beta blocker drug therapy. The patient also reported reversal of impaired cognition and symptoms associated with atrial fibrillation and ischaemic cardiomyopathy, including light-headedness, fatigue and weakness. This case demonstrates that dietary and lifestyle modifications have the potential to improve symptoms of cardiovascular disease and reduce polypharmacy along with associated negative consequences in the elderly.

Variation in minimum desired cardiovascular disease-free longevity benefit from statin and antihypertensive medications: a cross-sectional study of patient and primary care physician perspectives

OBJECTIVE

Expressing therapy benefit from a lifetime perspective, instead of only a 10-year perspective, is both more intuitive and of growing importance in doctor-patient communication. In cardiovascular disease (CVD) prevention, lifetime estimates are increasingly accessible via online decision tools. However, it is unclear what gain in life expectancy is considered meaningful by those who would use the estimates in clinical practice. We therefore quantified lifetime and 10-year benefit thresholds at which physicians and patients perceive statin and antihypertensive therapy as meaningful, and compared the thresholds with clinically attainable benefit.

DESIGN

Cross-sectional study.

SETTINGS

(1) continuing medical education conference in December 2016 for primary care physicians;(2) information session in April 2017 for patients.

PARTICIPANTS

400 primary care physicians and 523 patients in the Netherlands.

OUTCOME

Months gain of CVD-free life expectancy at which lifelong statin therapy is perceived as meaningful, and months gain at which 10 years of statin and antihypertensive therapy is perceived as meaningful. Physicians were framed as users for lifelong and prescribers for 10-year therapy.

RESULTS

Meaningful benefit was reported as median (IQR). Meaningful lifetime statin benefit was 24 months (IQR 23-36) in physicians (as users) and 42 months (IQR 12-42) in patients willing to consider therapy. Meaningful 10-year statin benefit was 12 months (IQR 10-12) for prescribing (physicians) and 14 months (IQR 10-14) for using (patients). Meaningful 10-year antihypertensive benefit was 12 months (IQR 8-12) for prescribing (physicians) and 14 months (IQR 10-14) for using (patients). Women desired greater benefit than men. Age, CVD status and co-medication had minimal effects on outcomes.

CONCLUSION

Both physicians and patients report a large variation in meaningful longevity benefit. Desired benefit differs between physicians and patients and exceeds what is clinically attainable. Clinicians should recognise these discrepancies when prescribing therapy and implement individualised medicine and shared decision-making. Decision tools could provide information on realistic therapy benefit.

A defined, plant-based diet utilized in an outpatient cardiovascular clinic effectively treats hypercholesterolemia and hypertension and reduces medications

BACKGROUND

Cardiovascular disease (CVD) is a major economic burden in the United States. CVD risk factors, particularly hypertension and hypercholesterolemia, are typically treated with drug therapy. Five-year efficacy of such drugs to prevent CVD is estimated to be 5%. Plant-based diets have emerged as effective mitigators of these risk factors.

HYPOTHESIS

The implementation of a defined, plant-based diet for 4 weeks in an outpatient clinical setting may mitigate CVD risk factors and reduce patient drug burden.

METHODS

Participants consumed a plant-based diet consisting of foods prepared in a defined method in accordance with a food-classification system. Participants consumed raw fruits, vegetables, seeds, and avocado. All animal products were excluded from the diet. Participant anthropometric and hemodynamic data were obtained weekly for 4 weeks. Laboratory biomarkers were collected at baseline and at 4 weeks. Medication needs were assessed weekly. Data were analyzed using paired-samples t tests and 1-way repeated-measures ANOVA.

RESULTS

Significant reductions were observed for systolic (-16.6 mmHg) and diastolic (-9.1 mmHg) blood pressure (P < 0.0005), serum lipids (P ≤ 0.008), and total medication usage (P < 0.0005). Other CVD risk factors, including weight (P < 0.0005), waist circumference (P < 0.0005), heart rate (P = 0.018), insulin (P < 0.0005), glycated hemoglobin (P = 0.002), and high-sensitivity C-reactive protein (P = 0.001) were also reduced.

CONCLUSION

A defined, plant-based diet can be used as an effective therapeutic strategy in the clinical setting to mitigate cardiovascular risk factors and reduce patient drug burden.

Patient preferences for cardiovascular preventive medication: a systematic review

OBJECTIVE

To systematically review current evidence regarding the minimum acceptable risk reduction of a cardiovascular event that patients feel would justify daily intake of a preventive medication.

METHODS

We used the Web of Science to track the forward and backward citations of a set of five key articles until 15 November 2016. Studies were eligible if they quantitatively assessed the minimum acceptable benefit-in absolute values-of a cardiovascular disease preventive medication among a sample of the general population and required participants to choose if they would consider taking the medication.

RESULTS

Of 341 studies screened, we included 22, involving a total of 17 751 participants: 6 studied prolongation of life (POL), 12 studied absolute risk reduction (ARR) and 14 studied number needed to treat (NNT) as measures of risk reduction communicated to the patients. In studies framed using POL, 39%-54% (average: 48%) of participants would consider taking a medication if it prolonged life by <8 months and 56%-73% (average: 64%) if it prolonged life by ≥8 months. In studies framed using ARR, 42%-72% (average: 54%) of participants would consider taking a medication that reduces their 5-year cardiovascular disease (CVD) risk by <3% and 50%-89% (average: 77%) would consider taking a medication that reduces their 5-year CVD risk by ≥3%. In studies framed using 5-year NNT, 31%-81% (average: 60%) of participants would consider taking a medication with an NNT of >30 and 46%-87% (average: 71%) with an NNT of ≤30.

CONCLUSIONS

Many patients require a substantial risk reduction before they consider taking a daily medication worthwhile, even when the medication is described as being side effect free and costless.

Misleading Measurements: Modeling the Effects of Blood Pressure Misclassification in a United States Population

Objective. The clinical diagnosis of hypertension is subject to misclassification, and this may be clinically important. This article calculates positive and negative predictive values for blood pressure measurement and assesses the frequency of clinically important blood pressure misclassification. Design, Setting, and Participants. A modeling study was carried out on 4763 adults in the National Health and Nutrition Examination Survey (NHANES) population. True treatment eligibility was determined by applying Joint National Committee (JNC) VII criteria to individuals in the study population. Each individual was also allocated a series of blood pressures incorporating an error term reflecting day-to-day measurement variation. Test positives are persons classified as needing treatment on the basis of the mean of 2 blood pressure measurements. Measurements and Main Results. Positive predictive values of a diagnosis of hypertension based on 2 measurements were calculated for each age-sex group. Low-risk false positives and highrisk false negatives were categorized as clinically important errors. Positive predictive values are high in persons older than age 65. In persons ages 16 to 34, the positive predictive value is 0.24 (95% confidence interval [CI]: 0.17–0.32) in men and 0.16 (95% CI: 0.06–0.26) in women. Persons younger than age 35 are almost always at low risk of cardiovascular disease, and therefore this misclassification is clinically important. Even with 24-hour ambulatory blood pressure measurement, positive predictive values in young adults are under 0.5. Conclusions. Blood pressure estimation is a poor diagnostic test in low-prevalence populations such as young adults. Estimation of blood pressure should be informed by prior estimation of cardiovascular risk.

The development of a personalized patient education tool for decision making for postmenopausal women with osteoporosis

A personalized patient education tool for decision making (PET) for postmenopausal women with osteoporosis was developed by means of a systematic development approach. A prototype was constructed and refined by involving various professionals and patients. Professionals and patients expressed a positive attitude towards the use of the PET.

INTRODUCTION

The purpose was to systematically develop a paper-based personalized PET to assist postmenopausal women with osteoporosis in selecting a treatment in line with their personal values and preferences.

METHODS

The development of the PET was based on a systematic process including scope, design, development of a prototype, and alpha testing among professionals and patients by semi-structured interviews.

RESULTS

The design and development resulted in a four-page PET prototype together with a one-page fact sheet of the different drug options. The prototype PET provided the personal risk factors, the estimated individualized risk for a future major osteoporotic fracture and potential reduction with drugs, and a summary of advantages and disadvantages whether or not to start drugs. The drug fact sheet presents five attributes of seven drugs in a tabular format. The alpha testing with professionals resulted in some adaptations, e.g., inclusion of the possibility to calculate fracture risk based on various individual risk scoring methods. Important results from the alpha testing with patients were differences in the fracture risk percentage which was seen as worthwhile to start drugs, the importance of an overview of side effects, and of the timing of the PET into the patient pathway. All women indicated that the PET could be helpful for their decision to select a treatment.

CONCLUSION

Physicians and patients expressed a positive attitude towards the use of the proposed PET. Further research would be needed to test the effects of the PET on feasibility in clinical workflow and on patient outcomes.

Communicating risk using absolute risk reduction or prolongation of life formats: cluster-randomised trial in general practice

BACKGROUND

It is important that patients are well-informed about risks and benefits of therapies to help them decide whether to accept medical therapy. Different numerical formats can be used in risk communication but It remains unclear how the different formats affect decisions made by real-life patients.

AIM

To compare the impact of using Prolongation Of Life (POL) and Absolute Risk Reduction (ARR) information formats to express effectiveness of cholesterol-lowering therapy on patients' redemptions of statin prescriptions, and on patients' confidence in their decision and satisfaction with the risk communication.

DESIGN AND SETTING

Cluster-randomised clinical trial in general practices. Thirty-four Danish GPs from 23 practices participated in a primary care-based clinical trial concerning use of quantitative effectiveness formats for risk communication in health prevention consultations.

METHOD

GPs were cluster-randomised (treating practices as clusters) to inform patients about cardiovascular mortality risk and the effectiveness of statin treatment using either POL or ARR formats. Patients' redemptions of statin prescriptions were obtained from a regional prescription database. The COMRADE questionnaire was used to measure patients' confidence in their decision and satisfaction with the risk communication.

RESULTS

Of the 240 patients included for analyses, 112 were allocated to POL information and 128 to ARR. Patients redeeming a statin prescription totalled six (5.4%) when informed using POL, and 32 (25.0%) when using ARR. The level of confidence in decision and satisfaction with risk communication did not differ between the risk formats.

CONCLUSION

Patients redeemed statin prescriptions less often when their GP communicated treatment effectiveness using POL compared with ARR.

The Impact of Advice Seekers' Need Salience and Doctors' Communication Style on Attitude and Decision Making: A Web-Based Mammography Consultation Role Play

Background

Patients and advice seekers come to a medical consultation with typical needs, and physicians require adequate communication skills in order to address those needs effectively. It is largely unclear, however, to what extent advice seekers’ attitudes toward a medical procedure or their resulting decisions are influenced by a physician’s communication that ignores or explicitly takes these needs into account.

Objective

This experimental study tested how advice seekers’ salient needs and doctor’s communication styles influenced advice seekers’ attitudes toward mammography screening and their decision whether or not to participate in this procedure.

Methods

One hundred women (age range 20-47 years, mean 25.22, SD 4.71) participated in an interactive role play of an online consultation. During the consultation, a fictitious, program-controlled physician provided information about advantages and disadvantages of mammography screening. The physician either merely communicated factual medical information or made additional comments using a communication style oriented toward advice seekers’ typical needs for clarity and well-being. Orthogonal to this experimental treatment, participants’ personal needs for clarity and for well-being were either made salient before or after the consultation with a needs questionnaire. We also measured all participants’ attitudes toward mammography screening and their hypothetical decisions whether or not to participate before and after the experiment.

Results

As assumed, the participants expressed strong needs for clarity (mean 4.57, SD 0.42) and for well-being (mean 4.21, SD 0.54) on 5-point Likert scales. Making these needs salient or not revealed significant interaction effects with the physician’s communication style regarding participants’ attitude change (F_1,92=7.23, P=.009, η²=.073) and decision making (F_1,92=4.43, P=.038, η²=.046). Those participants whose needs were made salient before the consultation responded to the physician’s communication style, while participants without salient needs did not. When the physician used a need-oriented communication style, those participants with salient needs had a more positive attitude toward mammography after the consultation than before (mean 0.13, SD 0.54), while they changed their attitude in a negative direction when confronted with a purely fact-oriented communication style (mean −0.35, SD 0.80). The same applied to decision modification (need-oriented: mean 0.10, SD 0.99; fact-oriented: mean −0.30, SD 0.88).

Conclusions

The findings underline the importance of communicating in a need-oriented style with patients and advice seekers who are aware of their personal needs. Ignoring the needs of those people appears to be particularly problematic. So physicians’ sensitivity for advice seekers’ currently relevant needs is essential.

Decisions on statin therapy by patients' opinions about survival gains: cross sectional survey of general practitioners

Background

Guidelines for primary prevention of cardiovascular disease provide little guidance on how patients’ preferences should be taken into account. We wanted to explore whether general practitioners (GPs) are sensitive to patient preferences regarding survival gains from statin therapy.

Methods

In a cross sectional, online survey 3,270 Norwegian GPs were presented with a 55 year old patient with an unfavourable cardiovascular risk profile. He expressed preferences for statin therapy by indicating a minimum survival gain that would be considered a substantial benefit. This survival gain varied across six versions of the vignette: 8, 4 and 2 years, and 12, 6 and 3 months, respectively. Participants were randomly allocated to one version only. We asked whether the GPs would recommend the patient to take a statin. Subsequently we asked the GPs to estimate the average survival gain of life long simvastatin therapy for patients with a similar risk profile.

Results

We received 1,296 responses (40 %). Across levels of survival gains (8 years to 3 months) the proportion of GPs recommending statin therapy did not vary significantly (OR per level 1.07, 95 % CI 0.99 to 1.16). The GP’s own estimate of survival gain was a statistically significant predictor of recommending therapy (OR per year adjusted for the GPs’ age, sex, speciality attainment and number of patients listed 3.07, CI 2.55 to 3.69).

Conclusion

GPs were insensitive to patient preferences regarding survival gain when recommending statin therapy. The GPs' recommendations were strongly associated with their own estimates of survival gain.

Prioritizing health outcomes in a limited world: writing lipid guidelines

PURPOSE OF REVIEW

Guidelines are increasing in importance as healthcare becomes standardized. This article examines the processes by which the new US American College of Cardiology-American Heart Association and UK National Institute of Health and Care Excellence lipid guidelines came to their conclusions and how the nature of the evidence base and health economics contributed to the recommendations made.

RECENT FINDINGS

The writing of guidelines is becoming a systematic formal process with increasing emphasis on maintaining integrity, minimizing conflicts of interest and using consistent systematic methods to define the evidence base, grade its quality and then make recommendations. These processes are illustrated by showing why new cardiovascular disease risk assessment tools were required, what recommendations could be made about diet and lifestyle, why a fixed-dose drug treatment protocol as opposed to a target-based approach was recommended for the management of patients in secondary prevention, diabetes and primary prevention and how these would impact clinical practice.

SUMMARY

Modern systematic evidence assessment and economic appraisal convincingly favour the use of lipid-lowering drugs especially statins at higher doses than currently prescribed in secondary prevention and at lower risk thresholds in primary care than previously imagined. As long-term adherence to treatment is required patient choice is key to realizing the benefits of these interventions.

Plant-Based Diets for the Prevention and Treatment of Disabling Diseases

Overestimates of the efficacy of surgical and pharmacological interventions for the prevention and treatment of chronic disease and underestimates of the associated risks may bias physicians and patients against lifestyle medicine interventions that can be cheaper, safer, and more effective by treating the underlying cause of disease. The leading causes of both death and disability in the United States are diet, followed by smoking. The food and tobacco industries share similar tactics to downplay and obfuscate the risks associated with their products, but physicians can educate themselves about the role lifestyle interventions can play in the prevention and treatment of chronic disease. For example, a diet centered around whole plant foods can be used to successfully treat angina and painful diabetic neuropathy and may help prevent low-back pain and Alzheimer’s disease, all perhaps because of a common underlying vascular component. The delay between recognizing the risks of smoking and effective public health measures may have cost millions of lives. Similar delays in stopping dietary diseases may cost millions more.

"My doctor has changed my pills without telling me": impact of generic medication switches in stroke survivors

Generic (i.e. non-branded medicine) and therapeutic (i.e. a less expensive drug from the same class) substitution of medication provides considerable financial savings, but may negatively impact on patients. We report secondary qualitative/quantitative analysis of stroke survivors from a pilot randomised controlled brief intervention to increase adherence to medication. Patients' experiences of medication changes were examined in conjunction with electronically-recorded medication adherence. Twenty-eight patients reported frequent medication changes (e.g. size/shape/colour/packaging) and two-thirds of these reported negative effects, resulting in, at least, confusion and, at worst, mistakes in medication-taking. Patients reporting a direct effect on their medication-taking (n = 6) demonstrated poorer objectively-measured adherence (i.e. % doses taken on schedule) than those reporting confusion [mean difference = 19.9, 95% CI (2.0, 37.8)] or no problems [mean difference = 20.6, 95% CI (1.6, 40.0)]. Changes to medication resulting from switching between generic brands can be associated with notable problems, including poorer medication adherence, for a significant minority.

Comparison of cardiovascular disease risk calculators

PURPOSE OF REVIEW

The cardiovascular benefit of many preventive interventions (like statins) is strongly dependent on the baseline cardiovascular risk of the patient. Many lipid and vascular primary prevention guidelines advocate for the use of cardiovascular risk calculators.

RECENT FINDINGS

There are over 100 cardiovascular risk prediction models, and some of these models have spawned scores of calculators. Only about 25 of these models/calculators have been externally validated. The ability to identify who will have events frequently varies little (<5%) between models. However, disagreement between risk calculators is common with one in three paired comparisons disagreeing on risk category. In part, this disagreement is because calculators vary according to the database they are derived from, choice of clinical endpoints and risk interval duration upon which the estimate is based. Additional risk factors do little to improve the basic risk predictions performance, except perhaps coronary artery calcium which still requires further study before regular use.

SUMMARY

The estimates provided by cardiovascular risk calculators are ballpark approximations and have a margin of error. Physicians should use models derived from, or calibrated for, populations similar to theirs and understand the endpoints, duration, and special features of their selected calculator.

Low adherence to secondary prophylaxis among clients diagnosed with rheumatic fever, Jamaica

OBJECTIVES

To determine the level of adherence and possible barriers to secondary prophylaxis among clients with rheumatic fever in Kingston, Jamaica.

METHODS

Cross-sectional survey of 39 clients diagnosed with rheumatic fever, receiving penicillin prophylaxis for more than a year using a 22-item self-administered questionnaire on adherence to secondary prophylaxis and knowledge of rheumatic fever. The patients' records were reviewed to determine the number of prophylaxis injections the patients received for the year 2010.

RESULTS

The majority of participants (74%) were females and 51% were adults. Only 48·7% had a high level of adherence. The majority (72%) had low knowledge levels regarding their illness, while only 5% had a high knowledge level score. Most clients (70%) strongly agreed that nurses and doctors encouraged them to take their prophylaxis. However, over 60% reported that they travelled long distances and or waited long periods to get their injections. One-third reported that they missed appointments because of fear of injections and having to take time off from work or school.

DISCUSSION

Clients attending the health centers studied had limited knowledge about rheumatic fever. Barriers to adherence included fear of the injections, long commutes, and long waiting periods at the facilities studied.

Starting and staying on preventive medication for cardiovascular disease

PURPOSE OF REVIEW

To synthesize the qualitative research literature regarding medication use to prevent cardiovascular disease in order to explain the variation in healthcare professional (HCP) and patient behaviours, and to evaluate the implications for practice.

RECENT FINDINGS

The decision to start preventive medication is affected by the patient-HCP relationship and by the design of the service. Both HCPs and patients are influenced by their understanding of the evidence regarding the value of preventive interventions; their values and preferences; and their sociopolitical context and the organizational structure of their practice environment. The design of their service affects uptake as a consequence of its impact on clinical communication and the extent to which the service is tailored to the needs of the local community. Continuing to take prescribed medication is affected by both contextual and practical factors. Recommendations for practice can be split into those with a clinical focus and those with a patient or community focus. More sophisticated analyses have moved beyond recommendations for patient and HCP education, and address constraints in the organization of clinical services and the social context of evidence translation.

SUMMARY

Qualitative health research provides important insights into the experience of and context for decision making about medication prescription and adherence that can help efforts to prevent cardiovascular disease.

Patients' expectations of screening and preventive treatments

PURPOSE

An informed decision to accept a health care intervention requires an understanding of its likely benefit. This study assessed participants' estimates of the benefit, as well as minimum acceptable benefit, of screening for breast and bowel cancer and medication to prevent hip fracture and cardiovascular disease.

METHODS

Three general practitioners sent questionnaires to all registered patients aged 50 to 70 years. Patients agreeing to participate in the study were asked to estimate the number of events (fractures or deaths) prevented in a group of 5,000 patients undergoing each intervention over a period of 10 years, and to indicate the minimum number of events avoided by the intervention that they considered justified its use. The proportions of participants that overestimated each intervention's benefit were calculated, and univariate and multivariable analyses of predictors of response were performed.

RESULTS

The participation rate was 36%: 977 patients were invited to participate in the study, and 354 returned a completed questionnaire. Participants overestimated the degree of benefit conferred by all interventions: 90% of participants overestimated the effect of breast cancer screening, 94% overestimated the effect of bowel cancer screening, 82% overestimated the effect of hip fracture preventive medication, and 69% overestimated the effect of preventive medication for cardiovascular disease. Estimates of minimum acceptable benefit were more conservative, but other than for cardiovascular disease mortality prevention, most respondents indicated a minimum benefit greater than these interventions achieve. A lower level of education was associated with higher estimates of minimum acceptable benefit for all interventions.

CONCLUSION

Patients overestimated the risk reduction achieved with 4 examples of screening and preventive medications. A lower level of education was associated with higher minimum benefit to justify intervention use. This tendency to overestimate benefits may affect patients' decisions to use such interventions, and practitioners should be aware of this tendency when discussing these interventions with patients.

Medication effectiveness may not be the major reason for accepting cardiovascular preventive medication: a population-based survey

BACKGROUND

Shared decision-making and patients' choice of interventions are areas of increasing importance, not least seen in the light of the fact that chronic conditions are increasing, interventions considered important for public health, and still non-acceptance of especially risk-reducing treatments of cardiovascular diseases (CVD) is prevalent. A better understanding of patients' medication-taking behavior is needed and may be reached by studying the reasons why people accept or decline medication recommendations. The aim of this paper was to identify factors that may influence people's decisions and reasoning for accepting or declining a cardiovascular preventive medication offer.

METHODS

From a random sample of 4,000 people aged 40-59 years in a Danish population, 1,169 participants were asked to imagine being at increased risk of cardiovascular disease and being offered a preventive medication. After receiving 'complete' information about effectiveness of the medication they were asked whether they would accept medication. Finally, they were asked about reasons for the decision.

RESULTS

A total of 725 (67%) of 1,082 participants accepted the medication offer. Even quite large effects of medication (up to 8 percentage points absolute risk reduction) had a smaller impact on acceptance to medication than personal experience with cardiovascular disease. Furthermore, increasing age of the participant and living with a partner were significantly associated with acceptance. Some 45% of the respondents accepting justified their choice as being for health reasons, and they were more likely to be women, live alone, have higher income and higher education levels. Among those who did not accept the medication offer, 56% indicated that they would rather prefer to change lifestyle.

CONCLUSIONS

Medication effectiveness seems to have a moderate influence on people's decisions to accept preventive medication, while factors such as personal experience with cardiovascular disease may have an equally strong or stronger influence, indicating that practitioners could do well to carefully identify the reasons for their patients' treatment decisions.

Differing perceptions of intervention thresholds for fracture risk: a survey of patients and doctors

This survey suggests that patients are prepared to accept higher absolute fracture risk than doctors, before considering pharmacological therapy to be justified. Patients require that drug treatments confer substantial fracture risk reductions in order to consider long-term therapy.

INTRODUCTION

Absolute fracture risk estimates are now incorporated into osteoporosis treatment guidelines. At present, little is known about how patients regard fracture risk and its management. We set out to describe and compare the views of patients and doctors on the level of fracture risk at which drug treatment is justified.

METHODS

A cross-sectional survey was conducted on 114 patients referred for bone density measurement and 161 doctors whose practice includes management of osteoporosis. Participants were asked about fracture risk thresholds for pharmacological intervention.

RESULTS

The absolute risk of both major osteoporotic fracture and hip fracture at which drug treatment was considered by patients to be justifiable was higher than that reported by doctors [major osteoporotic fracture, median (interquartile range): patients, 50% (25 to 60); doctors, 10% (10 to 20); P < 0.0001; hip fracture: patients, 50% (25 to 60); doctors, 10% (5 to 20); P < 0.0001]. Patients required that a drug provide a median 50% reduction in relative risk of fracture in order to consider taking long-term therapy, irrespective of the treatment mode or dosing schedule. Among doctors, there was an inverse relationship between the number of osteoporosis consultations conducted each month and threshold of risk for recommending drug treatment (r = -0.22 and r = -0.29 for major osteoporotic fracture and hip fracture, respectively, P < 0.01 for both)

CONCLUSIONS

Patients are prepared to accept higher absolute fracture risk than doctors, before considering pharmacological therapy to be justified. Patients require that drug treatments confer substantial fracture risk reductions in order to consider long-term therapy.

Patient-specific factors relating to medication adherence in a post-percutaneous coronary intervention cohort

OBJECTIVE

To explore the association between medication adherence and qualitatively characterised patient-specific themes relating to medication adherence in patients following percutaneous coronary intervention (PCI).

METHODS

Data-collection questionnaires and qualitative topic guides were piloted in two patients. A validated questionnaire generated an adherence score for a convenience sample of 20 patients within 7 days of PCI. Semi-structured qualitative interviews were subsequently carried out with all patients to explore patient-specific themes relating to measured medication adherence.

KEY FINDINGS

Fourteen out of 20 patients (70%) had scores indicative of good adherence. Key factors associated with good adherence included having a good relationship with the doctor, having an understanding of the condition, knowledge of the indications and consequences of non-adherence, perceived health benefits and medications eliciting tangible symptom control. There were misconceptions of concern regarding adverse drug reactions and the importance of aspirin, both of which had a negative effect on adherence. The role of the community pharmacist was sometimes, although not always, misunderstood.

CONCLUSION

This study suggests there is an association between patients' beliefs, knowledge, understanding and misconceptions about medication and their adherence in a post-PCI cohort. To optimise medication adherence it is vital for prescribers to remain patient-focused and cognisant of patient-specific themes relating to medication adherence.

Effect of bariatric surgery on cardiovascular risk profile

Obesity is associated with increased risk for cardiovascular (CV) disease (CVD) and CV mortality. Bariatric surgery has been shown to resolve or improve CVD risk factors, to varying degrees. The objective of this systematic review was to determine the impact of bariatric surgery on CV risk factors and mortality. A systematic review of the published research was performed to evaluate evidence regarding CV outcomes in morbidly obese bariatric patients. Two major databases (PubMed and the Cochrane Library) were searched. The review included all original reports reporting outcomes after bariatric surgery, published in English, from January 1950 to July 2010. In total, 637 studies were identified from the initial screen. After applying inclusion and exclusion criteria, 52 studies involving 16,867 patients were included (mean age 42 years, 78% women). The baseline prevalence of hypertension, diabetes, and dyslipidemia was 49%, 28%, and 46%, respectively. Mean follow-up was 34 months (range 3 to 155), and the average excess weight loss was 52% (range 16% to 87%). Most studies reported significant decreases postoperatively in the prevalence of CV risk factors, including hypertension, diabetes, and dyslipidemia. Mean systolic pressure reduced from to 139 to 124 mm Hg and diastolic pressure from 87 to 77 mm Hg. C-reactive protein decreased, endothelial function improved, and a 40% relative risk reduction for 10-year coronary heart disease risk was observed, as determined by the Framingham risk score. In conclusion, this review highlights the benefits of bariatric surgery in reducing or eliminating risk factors for CVD. It provides further evidence to support surgical treatment of obesity to achieve CVD risk reduction.

Therapeutic decisions by number needed to treat and survival gains: a cross-sectional survey of lipid-lowering drug recommendations

BACKGROUND

Previous studies suggest that lay people have difficulties with evaluating effect size in terms of number needed to treat (NNT), but they are sensitive to effect size in terms of survival gains.

AIM

To explore whether GPs and internists are sensitive to NNT and survival gains when considering a lipid-lowering drug therapy.

DESIGN AND SETTING

Cross-sectional survey of primary prevention of cardiovascular disease with random allocation to different scenarios.

METHOD

GPs (n = 450) and internists (n = 450) were posted a vignette presenting a high-risk patient and a novel drug, 'neostatin'. The benefit was described in terms of NNT or mean gain in disease-free survival. Each physician was randomly allocated to one version of the vignette. Outcome measures were evaluation of 'neostatin' on a Likert scale (0: very poor choice, 10: very good choice) and the proportion recommending 'neostatin'.

RESULTS

A total of 477 responses (53%) were received. Among responders to NNT scenarios, 26%, 31%, and 43% recommended 'neostatin' for NNT values of 34, 17, and 9 respectively. With equivalent disease-free survival gains of 9, 17, and 32 months, 40%, 49%, and 52% respectively recommended the drug. On the rating scale, mean values were 4.7, 5.0, and 5.5 across the respective NNT scenarios and 5.2, 6.2, and 6.1 across the scenarios presenting survival gains. Differences in trends between the two formats were not statistically significant. In total, 33% recommended 'neostatin' when presented with NNT values, compared to 47% when presented with survival gain (χ(2) = 9.2, P= 0.002).

CONCLUSION

Physicians presented with survival gains were more likely to recommend the therapy than those presented with NNT. Sensitivity to effect size was similar for both effect formats.

Patient preference for autonomy: does it change as risk rises?

BACKGROUND

It is unclear how patient preferences for autonomy vary given different severity of a single condition.

OBJECTIVE

To assess patient preferences for autonomy in making decisions about taking medication to prevent a heart attack, across a wide range of personal calculated cardiovascular disease (CVD) 5-year risk.

METHODS

Consecutive eligible patients in family practice waiting rooms in Auckland, New Zealand self-completed a questionnaire. Questions related to a hypothetical cardiovascular medication, where risks and benefits were framed from their personal predicted 5-year CVD risk. Participant preference for autonomy was measured by ranking their decision-making preference on 5-point scale from 'doctor only' to 'patient only'.

RESULTS

There were 934 participants, with personal predicted 5-year cardiovascular risks that ranged from 5% to 30%. Preference for autonomy decreased as CVD risk increased, after adjustment for age, gender, numeracy and ethnicity. Preference for autonomy increased independently among younger participants, women and those who were more numerate. Compared to participants of European ethnicity, those of Pacific, East Asian and Indian Asian ethnicity were more likely to want the doctor to decide.

CONCLUSIONS

No combination of predicted risk, demographics or attitudes strongly predicted the preference of an individual patient. Clinicians should therefore seek to understand and confirm each patient's preferences.

Patient and general practitioner attitudes to taking medication to prevent cardiovascular disease after receiving detailed information on risks and benefits of treatment: a qualitative study

BACKGROUND

There are now effective drugs to prevent cardiovascular disease and guidelines recommend their use. Patients do not always choose to accept preventive medication at levels of risk reduction recommended in guidelines. The purpose of the study was to identify and explore the attitudes of patients and general practitioners towards preventative medication for cardiovascular disease (CVD) after they have received information about it; to identify implications for practice and prescribing.

METHODS

Qualitative interviews with GPs and patients following presentation of in depth information about CVD risks and the absolute effects of medication.

SETTING

GP practices in Birmingham, United Kingdom.

RESULTS

In both populations: wide variation on attitudes to preventative medication; concerns about unnecessary drug taking & side effects; preferring to consider lifestyle changes first. In patient population: whatever their attitudes to medication were, the vast majority explained that they would ultimately do what their GP recommended; there was some misunderstanding of the distinction between curative and preventative medication. A common theme was the degree of trust in their doctors' judgement and recommendations, which contrasted with scepticism of the role of pharmaceutical companies and academics. Scepticism in guidelines was also common among doctors although many nevertheless recommended treatment for their patients

CONCLUSIONS

A guideline approach to prescribing preventative medication could be against the interests and preferences of the patient. GPs must take extra care to explain what preventative medication is and why it is recommended, attempt to discern preferences and make recommendations balancing these potentially conflicting concerns.

A randomized questionnaire-based study on the impact of providing numerical information on colorectal cancer screening

OBJECTIVES

To establish whether the provision of numerical data using pictograms and framed as event rates affects subjects' attitudes to colorectal cancer (CRC) screening.

DESIGN

Randomized questionnaire and telephone study comparing a control group given standard NHS CRC information leaflets with an intervention group given the same leaflet but enhanced with additional numerical and pictorial information.

SETTING

District General hospital and two general practices in North East England. Study carried out immediately prior to the introduction of CRC screening.

PARTICIPANTS

A total of 478 non-gastroenterological subjects (age range 60-70 years).

MAIN OUTCOME MEASURES

The difference in the two groups' overall wish to be screened; comparison of the impact of enhanced vs. unenhanced summary points in the NHS information leaflet; the summary point that most influenced their decision on screening; the views of the intervention group on the additional numerical and pictorial information provided.

RESULTS

A total of 256 (54%) responded (124 from the control group and 117 from the intervention group); 22% were interviewed by telephone; 90% of the control group and 85% of the intervention group wished to be screened (P = 0.34). Provision of numerical and pictorial information significantly changed the impact of five of the six summary points on the decision to be screened. Sixty-two percent of the intervention group found the pictograms helpful while 83% of those interviewed by telephone found the numerical data helpful; 73% of the control group when given by telephone the additional numerical information given to the intervention group said this would have been useful in aiding their decision-making.

CONCLUSION

Providing additional numerical information would enhance the credibility of the screening programme without necessarily reducing the numbers screened.

Anticipated longevity among lay people screened for cardiovascular risk factors: A cross-sectional questionnaire study

Background: In terms of mental health and quality of life previous studies have largely failed to show long-term effects of cardiovascular risk information. Such information may still have an impact of a more subtle nature. We aimed to explore the potential impact of cardiovascular risk information on lay people’s anticipations of their own longevity. Methods: In 2002 11,284 Norwegians were invited to take part in a health survey. Participants (n = 6,845) received comprehensive written information about their personal risk factors for cardiovascular disease. About six months later we selected 752 high risk and 996 low risk individuals for a cross-sectional survey. Participants were mailed a questionnaire and informed about the life expectancy for women and men in Norway. Subsequently they were asked whether they expected to live longer, shorter than or approximately as long as the mean figures. Results: The response rate was 75% (n = 1,314). Whereas 210 respondents (16%) expected to live shorter than the mean, 198 (15%) expected to live longer. In a multivariate regression model high risk of cardiovascular disease (CVD) was associated with lower anticipated longevity (odds ratio 2.4, 95% confidence interval 1.7—3.3). Other predictors of low anticipation were use of lipid lowering drugs and a family history of heart attack before the age of 60. Higher age, male sex, better education and good self-reported health were associated with high anticipations. Conclusions: A CVD risk label was only moderately associated with lay people’s anticipated longevity. The majority expected to live as long as the mean, regardless of risk status.

Improving adherence to medication in stroke survivors (IAMSS): a randomised controlled trial: study protocol

Background

Adherence to therapies is a primary determinant of treatment success, yet the World Health Organisation estimate that only 50% of patients who suffer from chronic diseases adhere to treatment recommendations. In a previous project, we found that 30% of stroke patients reported sub-optimal medication adherence, and this was associated with younger age, greater cognitive impairment, lower perceptions of medication benefits and higher specific concerns about medication. We now wish to pilot a brief intervention aimed at (a) helping patients establish a better medication-taking routine, and (b) eliciting and modifying any erroneous beliefs regarding their medication and their stroke.

Methods/Design

Thirty patients will be allocated to a brief intervention (2 sessions) and 30 to treatment as usual. The primary outcome will be adherence measured over 3 months using Medication Event Monitoring System (MEMS) pill containers which electronically record openings. Secondary outcomes will include self reported adherence and blood pressure.

Discussion

This study shall also assess uptake/attrition, feasibility, ease of understanding and acceptability of this complex intervention.

Trial Registration

Current Controlled Trials ISRCTN38274953

Understanding the concept of medical risk reduction: a comparison between the UK and Germany

OBJECTIVE

To explore the views of German general practitioners, healthcare assistants, and laypeople about the minimum absolute risk reduction needed to justify drug treatment to prevent heart attacks, and to compare these views with those found in the UK.

METHOD

Qualitative content analysis study using the same clinical risk scenario and semi-structured interview schedule concerning a "pill" reducing cardiovascular risk as a recent UK study. The similarly recruited participants included six general practitioners (GPs), four healthcare assistants, and 12 laypeople, interviewed in 10 GP surgeries, two community settings, and five private homes.

RESULTS

In both countries, most participants, health professionals as well as laypeople, used risk numbers inconsistently in preventive treatment decisions. In Germany, some people explicitly rejected the probabilistic risk concept as a basis for such decisions. In the UK, people were generally more aware of cost for society than in Germany. Other factors were similar in both countries.

CONCLUSION

In both countries, preventive risk information is not well understood. Our results suggest that this is not only a technical communication problem.

LDL-cholesterol differences predicted survival benefit in statin trials by the surrogate threshold effect (STE)

OBJECTIVE

We describe a new statistical method called the surrogate threshold effect (STE) that estimates the threshold level of a surrogate needed in a clinical trial to predict a benefit in the target clinical outcome. In this article, we apply this method to the LDL-cholesterol biomarker surrogate and survival benefit-target outcome in statin trials.

STUDY DESIGN AND SETTING

We identified randomized trials comparing statin treatment to placebo treatment or no treatment and reporting all-cause and cardiovascular mortality. Trials with fewer than five all-cause deaths in at least one arm were excluded. Multiple regression modeled the reduction in all-cause and cardiovascular mortality as a function of LDL-cholesterol difference. The 95% confidence and 95% prediction bands were calculated and graphed to determine the minimum LDL-cholesterol difference (the surrogate threshold) below which there would be no predicted survival benefit.

RESULTS

In 16 qualifying trials, regression analysis yielded an all-cause mortality model whose prediction bands demonstrated no overall survival gain with LDL-cholesterol difference values below 1.5 mmol/L. The cardiovascular mortality model yielded prediction bands that demonstrated no cardiovascular survival benefit with LDL-cholesterol difference values below 1.4 mmol/L.

CONCLUSIONS

In a multitrial setting, the STE approach is a promising yet straightforward statistical method for evaluating the surrogate validity of biomarkers.