A Dynamic Risk Model for Multitype Recurrent Events.

Recurrent events can occur more than once in the same individual; such events may be of different types, known as multitype recurrent events. They are very common in longitudinal studies. Often there is a terminating event, after which no further events can occur. The risk of any event, including terminating events such as death or cure, is typically affected by prior events. We propose a flexible joint multitype recurrent-events model that explicitly provides estimates of the change in risk for each event due to subject characteristics, including number and type of prior events and the absolute risk for every event type (terminating and nonterminating), and predicts event-free survival probability over a desired time period. The model is fully parametric, and therefore a standard likelihood function and robust standard errors can be constructed. We illustrate the model with applications to the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (1994-2002) and provide discussion of the results and model features.

Orthostatic Hypotension, Hypertension Treatment, and Cardiovascular Disease: An Individual Participant Meta-Analysis.

Importance: There are ongoing concerns about the benefits of intensive vs standard blood pressure (BP) treatment among adults with orthostatic hypotension or standing hypotension. Objective: To determine the effect of a lower BP treatment goal or active therapy vs a standard BP treatment goal or placebo on cardiovascular disease (CVD) or all-cause mortality in strata of baseline orthostatic hypotension or baseline standing hypotension. Data Sources: Individual participant data meta-analysis based on a systematic review of MEDLINE, EMBASE, and CENTRAL databases through May 13, 2022. Study Selection: Randomized trials of BP pharmacologic treatment (more intensive BP goal or active agent) with orthostatic hypotension assessments. Data Extraction and Synthesis: Individual participant data meta-analysis extracted following PRISMA guidelines. Effects were determined using Cox proportional hazard models using a single-stage approach. Main Outcomes and Measures: Main outcomes were CVD or all-cause mortality. Orthostatic hypotension was defined as a decrease in systolic BP of at least 20 mm Hg and/or diastolic BP of at least 10 mm Hg after changing position from sitting to standing. Standing hypotension was defined as a standing systolic BP of 110 mm Hg or less or standing diastolic BP of 60 mm Hg or less. Results: The 9 trials included 29 235 participants followed up for a median of 4 years (mean age, 69.0 [SD, 10.9] years; 48% women). There were 9% with orthostatic hypotension and 5% with standing hypotension at baseline. More intensive BP treatment or active therapy lowered risk of CVD or all-cause mortality among those without baseline orthostatic hypotension (hazard ratio [HR], 0.81; 95% CI, 0.76-0.86) similarly to those with baseline orthostatic hypotension (HR, 0.83; 95% CI, 0.70-1.00; P = .68 for interaction of treatment with baseline orthostatic hypotension). More intensive BP treatment or active therapy lowered risk of CVD or all-cause mortality among those without baseline standing hypotension (HR, 0.80; 95% CI, 0.75-0.85), and nonsignificantly among those with baseline standing hypotension (HR, 0.94; 95% CI, 0.75-1.18). Effects did not differ by baseline standing hypotension (P = .16 for interaction of treatment with baseline standing hypotension). Conclusions and Relevance: In this population of hypertension trial participants, intensive therapy reduced risk of CVD or all-cause mortality regardless of orthostatic hypotension without evidence for different effects among those with standing hypotension.

Blood pressure lowering and risk of new-onset type 2 diabetes: an individual participant data meta-analysis.

BACKGROUND: Blood pressure lowering is an established strategy for preventing microvascular and macrovascular complications of diabetes, but its role in the prevention of diabetes itself is unclear. We aimed to examine this question using individual participant data from major randomised controlled trials. METHODS: We performed a one-stage individual participant data meta-analysis, in which data were pooled to investigate the effect of blood pressure lowering per se on the risk of new-onset type 2 diabetes. An individual participant data network meta-analysis was used to investigate the differential effects of five major classes of antihypertensive drugs on the risk of new-onset type 2 diabetes. Overall, data from 22 studies conducted between 1973 and 2008, were obtained by the Blood Pressure Lowering Treatment Trialists' Collaboration (Oxford University, Oxford, UK). We included all primary and secondary prevention trials that used a specific class or classes of antihypertensive drugs versus placebo or other classes of blood pressure lowering medications that had at least 1000 persons-years of follow-up in each randomly allocated arm. Participants with a known diagnosis of diabetes at baseline and trials conducted in patients with prevalent diabetes were excluded. For the one-stage individual participant data meta-analysis we used stratified Cox proportional hazards model and for the individual participant data network meta-analysis we used logistic regression models to calculate the relative risk (RR) for drug class comparisons. FINDINGS: 145 939 participants (88 500 [60·6%] men and 57 429 [39·4%] women) from 19 randomised controlled trials were included in the one-stage individual participant data meta-analysis. 22 trials were included in the individual participant data network meta-analysis. After a median follow-up of 4·5 years (IQR 2·0), 9883 participants were diagnosed with new-onset type 2 diabetes. Systolic blood pressure reduction by 5 mm Hg reduced the risk of type 2 diabetes across all trials by 11% (hazard ratio 0·89 [95% CI 0·84-0·95]). Investigation of the effects of five major classes of antihypertensive drugs showed that in comparison to placebo, angiotensin-converting enzyme inhibitors (RR 0·84 [95% 0·76-0·93]) and angiotensin II receptor blockers (RR 0·84 [0·76-0·92]) reduced the risk of new-onset type 2 diabetes; however, the use of ß blockers (RR 1·48 [1·27-1·72]) and thiazide diuretics (RR 1·20 [1·07-1·35]) increased this risk, and no material effect was found for calcium channel blockers (RR 1·02 [0·92-1·13]). INTERPRETATION: Blood pressure lowering is an effective strategy for the prevention of new-onset type 2 diabetes. Established pharmacological interventions, however, have qualitatively and quantitively different effects on diabetes, likely due to their differing off-target effects, with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers having the most favourable outcomes. This evidence supports the indication for selected classes of antihypertensive drugs for the prevention of diabetes, which could further refine the selection of drug choice according to an individual's clinical risk of diabetes. FUNDING: British Heart Foundation, National Institute for Health Research, and Oxford Martin School.

Effects of Intensive Blood Pressure Treatment on Orthostatic Hypotension : A Systematic Review and Individual Participant-based Meta-analysis.

BACKGROUND: Although intensive blood pressure (BP)-lowering treatment reduces risk for cardiovascular disease, there are concerns that it might cause orthostatic hypotension (OH). PURPOSE: To examine the effects of intensive BP-lowering treatment on OH in hypertensive adults. DATA SOURCES: MEDLINE, EMBASE, and Cochrane CENTRAL from inception through 7 October 2019, without language restrictions. STUDY SELECTION: Randomized trials of BP pharmacologic treatment (more intensive BP goal or active agent) that involved more than 500 adults with hypertension or elevated BP and that were 6 months or longer in duration. Trial comparisons were groups assigned to either less intensive BP goals or placebo, and the outcome was measured OH, defined as a decrease of 20 mm Hg or more in systolic BP or 10 mm Hg or more in diastolic BP after changing position from seated to standing. DATA EXTRACTION: 2 investigators independently abstracted articles and rated risk of bias. DATA SYNTHESIS: 5 trials examined BP treatment goals, and 4 examined active agents versus placebo. Trials examining BP treatment goals included 18 466 participants with 127 882 follow-up visits. Trials were open-label, with minimal heterogeneity of effects across trials. Intensive BP treatment lowered risk for OH (odds ratio, 0.93 [95% CI, 0.86 to 0.99]). Effects did not differ by prerandomization OH (P for interaction = 0.80). In sensitivity analyses that included 4 additional placebo-controlled trials, overall and subgroup findings were unchanged. LIMITATIONS: Assessments of OH were done while participants were seated (not supine) and did not include the first minute after standing. Data on falls and syncope were not available. CONCLUSION: Intensive BP-lowering treatment decreases risk for OH. Orthostatic hypotension, before or in the setting of more intensive BP treatment, should not be viewed as a reason to avoid or de-escalate treatment for hypertension. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute, National Institutes of Health. (PROSPERO: CRD42020153753).

Autologous Cardiac Stem Cell Injection in Patients with Hypoplastic Left Heart Syndrome (CHILD Study).

Mortality in infants with hypoplastic left heart syndrome (HLHS) is strongly correlated with right ventricle (RV) dysfunction. Cell therapy has demonstrated potential improvements of RV dysfunction in animal models related to HLHS, and neonatal human derived c-kit+ cardiac-derived progenitor cells (CPCs) show superior efficacy when compared to adult human cardiac-derived CPCs (aCPCs). Neonatal CPCs (nCPCs) have yet to be investigated in humans. The CHILD trial (Autologous Cardiac Stem Cell Injection in Patients with Hypoplastic Left Heart Syndrome) is a Phase I/II trial aimed at investigating intramyocardial administration of autologous nCPCs in HLHS infants by assessing the feasibility, safety, and potential efficacy of CPC therapy. Using an open-label, multicenter design, CHILD investigates nCPC safety and feasibility in the first enrollment group (Group A/Phase I). In the second enrollment group, CHILD uses a randomized, double-blinded, multicenter design (Group B/Phase II), to assess nCPC efficacy based on RV functional and structural characteristics. The study plans to enroll 32 patients across 4 institutions: Group A will enroll 10 patients, and Group B will enroll 22 patients. CHILD will provide important insights into the therapeutic potential of nCPCs in patients with HLHS.Clinical Trial Registration https://clinicaltrials.gov/ct2/home NCT03406884, First posted January 23, 2018.

Antihypertensive treatment and risk of cancer: an individual participant data meta-analysis.

BACKGROUND: Some studies have suggested a link between antihypertensive medication and cancer, but the evidence is so far inconclusive. Thus, we aimed to investigate this association in a large individual patient data meta-analysis of randomised clinical trials. METHODS: We searched PubMed, MEDLINE, The Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov from Jan 1, 1966, to Sept 1, 2019, to identify potentially eligible randomised controlled trials. Eligible studies were randomised controlled trials comparing one blood pressure lowering drug class with a placebo, inactive control, or other blood pressure lowering drug. We also required that trials had at least 1000 participant years of follow-up in each treatment group. Trials without cancer event information were excluded. We requested individual participant data from the authors of eligible trials. We pooled individual participant-level data from eligible trials and assessed the effects of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), ß blockers, calcium channel blockers, and thiazide diuretics on cancer risk in one-stage individual participant data and network meta-analyses. Cause-specific fixed-effects Cox regression models, stratified by trial, were used to calculate hazard ratios (HRs). The primary outcome was any cancer event, defined as the first occurrence of any cancer diagnosed after randomisation. This study is registered with PROSPERO (CRD42018099283). FINDINGS: 33 trials met the inclusion criteria, and included 260 447 participants with 15 012 cancer events. Median follow-up of included participants was 4·2 years (IQR 3·0-5·0). In the individual participant data meta-analysis comparing each drug class with all other comparators, no associations were identified between any antihypertensive drug class and risk of any cancer (HR 0·99 [95% CI 0·95-1·04] for ACEIs; 0·96 [0·92-1·01] for ARBs; 0·98 [0·89-1·07] for ß blockers; 1·01 [0·95-1·07] for thiazides), with the exception of calcium channel blockers (1·06 [1·01-1·11]). In the network meta-analysis comparing drug classes against placebo, we found no excess cancer risk with any drug class (HR 1·00 [95% CI 0·93-1·09] for ACEIs; 0·99 [0·92-1·06] for ARBs; 0·99 [0·89-1·11] for ß blockers; 1·04 [0·96-1·13] for calcium channel blockers; 1·00 [0·90-1·10] for thiazides). INTERPRETATION: We found no consistent evidence that antihypertensive medication use had any effect on cancer risk. Although such findings are reassuring, evidence for some comparisons was insufficient to entirely rule out excess risk, in particular for calcium channel blockers. FUNDING: British Heart Foundation, National Institute for Health Research, Oxford Martin School.

Blood pressure-lowering treatment for the prevention of cardiovascular events in patients with atrial fibrillation: An individual participant data meta-analysis.

BACKGROUND: Randomised evidence on the efficacy of blood pressure (BP)-lowering treatment to reduce cardiovascular risk in patients with atrial fibrillation (AF) is limited. Therefore, this study aimed to compare the effects of BP-lowering drugs in patients with and without AF at baseline. METHODS AND FINDINGS: The study was based on the resource provided by the Blood Pressure Lowering Treatment Trialists' Collaboration (BPLTTC), in which individual participant data (IPD) were extracted from trials with over 1,000 patient-years of follow-up in each arm, and that had randomly assigned patients to different classes of BP-lowering drugs, BP-lowering drugs versus placebo, or more versus less intensive BP-lowering regimens. For this study, only trials that had collected information on AF status at baseline were included. The effects of BP-lowering treatment on a composite endpoint of major cardiovascular events (stroke, ischaemic heart disease or heart failure) according to AF status at baseline were estimated using fixed-effect one-stage IPD meta-analyses based on Cox proportional hazards models stratified by trial. Furthermore, to assess whether the associations between the intensity of BP reduction and cardiovascular outcomes are similar in those with and without AF at baseline, we used a meta-regression. From the full BPLTTC database, 28 trials (145,653 participants) were excluded because AF status at baseline was uncertain or unavailable. A total of 22 trials were included with 188,570 patients, of whom 13,266 (7%) had AF at baseline. Risk of bias assessment showed that 20 trials were at low risk of bias and 2 trials at moderate risk. Meta-regression showed that relative risk reductions were proportional to trial-level intensity of BP lowering in patients with and without AF at baseline. Over 4.5 years of median follow-up, a 5-mm Hg systolic BP (SBP) reduction lowered the risk of major cardiovascular events both in patients with AF (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.83 to 1.00) and in patients without AF at baseline (HR 0.91, 95% CI 0.88 to 0.93), with no difference between subgroups. There was no evidence for heterogeneity of treatment effects by baseline SBP or drug class in patients with AF at baseline. The findings of this study need to be interpreted in light of its potential limitations, such as the limited number of trials, limitation in ascertaining AF cases due to the nature of the arrhythmia and measuring BP in patients with AF. CONCLUSIONS: In this meta-analysis, we found that BP-lowering treatment reduces the risk of major cardiovascular events similarly in individuals with and without AF. Pharmacological BP lowering for prevention of cardiovascular events should be recommended in patients with AF.

Association of Sustained Blood Pressure Control with Lower Risk for High-Cost Multimorbidities Among Medicare Beneficiaries in ALLHAT.

BACKGROUND: Clustering of chronic conditions is associated with high healthcare costs. Sustaining blood pressure (BP) control could be a strategy to prevent high-cost multimorbidity clusters. OBJECTIVE: To determine the association between sustained systolic BP (SBP) control and incident multimorbidity cluster dyads and triads. DESIGN: Cohort study of Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) linked to Medicare claims. PARTICIPANTS: ALLHAT included adults with hypertension and ≥1 coronary heart disease risk factor. This analysis was restricted to 5234 participants with ≥ 8 SBP measurements during a 48-month BP assessment period. MAIN MEASURES: SBP control was defined as <140 mm Hg at <50%, 50 to <75%, 75 to <100%, and 100% of study visits during the BP assessment period. High-cost multimorbidity clusters included dyads (stroke/chronic kidney disease [CKD], stroke/chronic obstructive pulmonary disease [COPD], stroke/heart failure [HF], stroke/asthma, COPD/CKD) and triads (stroke/CKD/asthma, stroke/CKD/COPD, stroke/CKD/depression, stroke/CKD/HF, stroke/HF/asthma) identified during follow-up. KEY RESULTS: Incident dyads occurred in 1334 (26%) participants and triads occurred in 481 (9%) participants over a median follow-up of 9.2 years. Among participants with SBP control at <50%, 50 to <75%, 75 to <100%, and 100% of visits, 32%, 23%, 23%, and 19% of participants developed high-cost dyads, respectively, and 13%, 9%, 8%, and 5% of participants developed high-cost triads, respectively. Compared to those with sustained BP control at <50% of visits, adjusted HRs (95% CI) for incident dyads were 0.66 (0.57, 0.75), 0.67 (0.59, 0.77), and 0.51 (0.42, 0.62) for SBP control at 50 to <75%, 75 to <100%, and 100% of visits, respectively. The corresponding HRs (95% CI) for incident triads were 0.69 (0.55, 0.85), 0.56 (0.44, 0.71), and 0.32 (0.22, 0.47). CONCLUSIONS: Among Medicare beneficiaries in ALLHAT, sustained SBP was associated with a lower risk of developing high-cost multimorbidity dyads and triads.

Statistical reanalysis of vascular event outcomes in primary and secondary vascular prevention trials.

BACKGROUND: Vascular prevention trials typically use dichotomous event outcomes although this may be inefficient statistically and gives no indication of event severity. We assessed whether ordinal outcomes would be more efficient and how to best analyse them. METHODS: Chief investigators of vascular prevention randomised controlled trials that showed evidence of either benefit or harm, or were included in a systematic review that overall showed benefit or harm, shared individual participant data from their trials. Ordered categorical versions of vascular event outcomes (such as stroke and myocardial infarction) were analysed using 15 statistical techniques and their results then ranked, with the result with the smallest p-value given the smallest rank. Friedman and Duncan's multiple range tests were performed to assess differences between tests by comparing the average ranks for each statistical test. RESULTS: Data from 35 trials (254,223 participants) were shared with the collaboration. 13 trials had more than two treatment arms, resulting in 59 comparisons. Analysis approaches (Mann Whitney U, ordinal logistic regression, multiple regression, bootstrapping) that used ordinal outcome data had a smaller average rank and therefore appeared to be more efficient statistically than those that analysed the original binary outcomes. CONCLUSIONS: Ordinal vascular outcome measures appear to be more efficient statistically than binary outcomes and provide information on the severity of event. We suggest a potential role for using ordinal outcomes in vascular prevention trials.

Prediction of individual life-years gained without cardiovascular events from lipid, blood pressure, glucose, and aspirin treatment based on data of more than 500 000 patients with Type 2 diabetes mellitus.

AIMS: Although group-level effectiveness of lipid, blood pressure, glucose, and aspirin treatment for prevention of cardiovascular disease (CVD) has been proven by trials, important differences in absolute effectiveness exist between individuals. We aim to develop and validate a prediction tool for individualizing lifelong CVD prevention in people with Type 2 diabetes mellitus (T2DM) predicting life-years gained without myocardial infarction or stroke. METHODS AND RESULTS: We developed and validated the Diabetes Lifetime-perspective prediction (DIAL) model, consisting of two complementary competing risk adjusted Cox proportional hazards functions using data from people with T2DM registered in the Swedish National Diabetes Registry (n = 389 366). Competing outcomes were (i) CVD events (vascular mortality, myocardial infarction, or stroke) and (ii) non-vascular mortality. Predictors were age, sex, smoking, systolic blood pressure, body mass index, haemoglobin A1c, estimated glomerular filtration rate, non- high-density lipoprotein cholesterol, albuminuria, T2DM duration, insulin treatment, and history of CVD. External validation was performed using data from the ADVANCE, ACCORD, ASCOT and ALLHAT-LLT-trials, the SMART and EPIC-NL cohorts, and the Scottish diabetes register (total n = 197 785). Predicted and observed CVD-free survival showed good agreement in all validation sets. C-statistics for prediction of CVD were 0.83 (95% confidence interval: 0.83-0.84) and 0.64-0.65 for internal and external validation, respectively. We provide an interactive calculator at www.U-Prevent.com that combines model predictions with relative treatment effects from trials to predict individual benefit from preventive treatment. CONCLUSION: Cardiovascular disease-free life expectancy and effects of lifelong prevention in terms of CVD-free life-years gained can be estimated for people with T2DM using readily available clinical characteristics. Predictions of individual-level treatment effects facilitate translation of trial results to individual patients.

Equalization of four cardiovascular risk algorithms after systematic recalibration: individual-participant meta-analysis of 86 prospective studies.

AIMS: There is debate about the optimum algorithm for cardiovascular disease (CVD) risk estimation. We conducted head-to-head comparisons of four algorithms recommended by primary prevention guidelines, before and after 'recalibration', a method that adapts risk algorithms to take account of differences in the risk characteristics of the populations being studied. METHODS AND RESULTS: Using individual-participant data on 360 737 participants without CVD at baseline in 86 prospective studies from 22 countries, we compared the Framingham risk score (FRS), Systematic COronary Risk Evaluation (SCORE), pooled cohort equations (PCE), and Reynolds risk score (RRS). We calculated measures of risk discrimination and calibration, and modelled clinical implications of initiating statin therapy in people judged to be at 'high' 10 year CVD risk. Original risk algorithms were recalibrated using the risk factor profile and CVD incidence of target populations. The four algorithms had similar risk discrimination. Before recalibration, FRS, SCORE, and PCE over-predicted CVD risk on average by 10%, 52%, and 41%, respectively, whereas RRS under-predicted by 10%. Original versions of algorithms classified 29-39% of individuals aged ≥40 years as high risk. By contrast, recalibration reduced this proportion to 22-24% for every algorithm. We estimated that to prevent one CVD event, it would be necessary to initiate statin therapy in 44-51 such individuals using original algorithms, in contrast to 37-39 individuals with recalibrated algorithms. CONCLUSION: Before recalibration, the clinical performance of four widely used CVD risk algorithms varied substantially. By contrast, simple recalibration nearly equalized their performance and improved modelled targeting of preventive action to clinical need.

Adaptive group-sequential design with population enrichment in phase 3 randomized controlled trials with two binary co-primary endpoints.

The use of co-primary endpoints in drug development allows investigators to capture an experimental intervention's multidimensional effect more comprehensively than a single primary endpoint. We propose the theoretical basis and development of an adaptive population enrichment design with co-primary endpoints, provide stage-wise boundary values for futility and efficacy, and discuss power under different efficacy configurations, subgroup prevalence, and analysis times using a pre-specified decision criterion. We considered a two-arm, two-stage, parallel group design where population enrichment occurs at the interim analysis by dropping any non-responsive subgroups. A test for efficacy is conducted only in the enriched population. Two binary endpoints are evaluated as co-primary endpoints. Our trial objective is to determine whether the experimental intervention is superior to the control intervention, with superiority required in both endpoints. We define the stopping boundary using alpha spending functions. Using a 0.025 significance level for each endpoint, we obtain the stage I threshold boundary values for futility and efficacy as -0.1040 and 2.2761, respectively, and the stage II boundary value for futility and efficacy is 2.2419. We show that in the presence of substantial heterogeneity of treatment effect, we gain more power to observe an effect in the subgroup where the benefits are greater. By allowing the dropping of non-responsive subgroups at an early stage, our design reduces the likelihood of obtaining false-negative results due to inclusion of the heterogeneous treatment effects of both subgroups, which would dilute the responsive subgroup's results.

Blood pressure-lowering treatment strategies based on cardiovascular risk versus blood pressure: A meta-analysis of individual participant data.

BACKGROUND: Clinical practice guidelines have traditionally recommended blood pressure treatment based primarily on blood pressure thresholds. In contrast, using predicted cardiovascular risk has been advocated as a more effective strategy to guide treatment decisions for cardiovascular disease (CVD) prevention. We aimed to compare outcomes from a blood pressure-lowering treatment strategy based on predicted cardiovascular risk with one based on systolic blood pressure (SBP) level. METHODS AND FINDINGS: We used individual participant data from the Blood Pressure Lowering Treatment Trialists' Collaboration (BPLTTC) from 1995 to 2013. Trials randomly assigned participants to either blood pressure-lowering drugs versus placebo or more intensive versus less intensive blood pressure-lowering regimens. We estimated 5-y risk of CVD events using a multivariable Weibull model previously developed in this dataset. We compared the two strategies at specific SBP thresholds and across the spectrum of risk and blood pressure levels studied in BPLTTC trials. The primary outcome was number of CVD events avoided per persons treated. We included data from 11 trials (47,872 participants). During a median of 4.0 y of follow-up, 3,566 participants (7.5%) experienced a major cardiovascular event. Areas under the curve comparing the two treatment strategies throughout the range of possible thresholds for CVD risk and SBP demonstrated that, on average, a greater number of CVD events would be avoided for a given number of persons treated with the CVD risk strategy compared with the SBP strategy (area under the curve 0.71 [95% confidence interval (CI) 0.70-0.72] for the CVD risk strategy versus 0.54 [95% CI 0.53-0.55] for the SBP strategy). Compared with treating everyone with SBP ≥ 150 mmHg, a CVD risk strategy would require treatment of 29% (95% CI 26%-31%) fewer persons to prevent the same number of events or would prevent 16% (95% CI 14%-18%) more events for the same number of persons treated. Compared with treating everyone with SBP ≥ 140 mmHg, a CVD risk strategy would require treatment of 3.8% (95% CI 12.5% fewer to 7.2% more) fewer persons to prevent the same number of events or would prevent 3.1% (95% CI 1.5%-5.0%) more events for the same number of persons treated, although the former estimate was not statistically significant. In subgroup analyses, the CVD risk strategy did not appear to be more beneficial than the SBP strategy in patients with diabetes mellitus or established CVD. CONCLUSIONS: A blood pressure-lowering treatment strategy based on predicted cardiovascular risk is more effective than one based on blood pressure levels alone across a range of thresholds. These results support using cardiovascular risk assessment to guide blood pressure treatment decision-making in moderate- to high-risk individuals, particularly for primary prevention.

Risk Factors Influencing Outcomes of Atrial Fibrillation in ALLHAT.

BACKGROUND AND AIMS: ALLHAT, a randomized, double-blind, active-controlled, multicenter clinical trial of high risk hypertensive participants, compared treatment with an ACE-inhibitor (lisinopril) or calcium channel blocker (amlodipine) with a diuretic (chlorthalidone). Primary outcome was the occurrence of fatal coronary heart disease or nonfatal myocardial infarction. For this report, post-hoc analyses were conducted to determine the contribution of baseline characteristics of participants with or without baseline or incident atrial fibrillation (AF) and atrial flutter (AFL) to stroke, heart failure (HF), coronary heart disease (CHD), and mortality outcomes. METHODS AND RESULTS: Minnesota Coding of baseline and biennial in-trial ECGs was used to determine the 334 baseline and 537 incident AF/AFL cases, respectively participants with AF/AFL: Cox regression was used to estimate hazard ratios of presence versus absence of either baseline or incident AF/AFL (as time-dependent covariate) for occurrence of stroke, CHD, HF, or mortality, while adjusting for selected baseline characteristics. Adjusted Cox regression was used to obtain hazard ratios (HRs) for presence versus absence of selected baseline characteristics among those with and without either baseline or incident AF/AFL. After adjusting for baseline characteristics, baseline AF/AFL was associated with stroke, HF, and mortality (HRs [95% CIs] 3.18, [2.34-4.33]; 2.65 [2.02-3.49]; and 2.10 [CI, 1.73-2.55], respectively, P < 0.05). Incident AF/AFL was a significant risk factor for HF and mortality (HRs 2.80 and 2.06, respectively, P < 0.05). Risk factor profiles for clinical outcomes for those with and without baseline or incident AF/AFL were largely similar. CONCLUSIONS: AF/AFL is a significant risk factor for stroke, HF, and mortality. Additional risk factors for these outcomes were generally similar for participants with and without baseline or incident AF/AFL.

Baseline Quality of Life and Risk of Stroke in the ALLHAT Study (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

BACKGROUND AND PURPOSE: The visual analogue scale is a self-reported, validated tool to measure quality of life (QoL). Our purpose was to determine whether baseline QoL predicted strokes in the ALLHAT study (Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial) and evaluate determinants of poststroke change in QoL. In the ALLHAT study, among the 33 357 patients randomized to treatment arms, 1525 experienced strokes; 1202 (79%) strokes were nonfatal. This study cohort includes 32 318 (97%) subjects who completed the baseline visual analogue scale QoL estimate. METHODS: QoL was measured on a visual analogue scale and adjusted using a Torrance transformation (transformed QoL [TQoL]). Kaplan-Meier curves and adjusted proportional hazards analyses were used to estimate the effect of TQoL on the risk of stroke, on a continuous scale (0-1) and by quartiles (≤0.81, >0.81≤0.89, >0.89≤0.95, >0.95). We analyzed the change from baseline to first poststroke TQoL using adjusted linear regression. RESULTS: After adjusting for multiple stroke risk factors, the hazard ratio for stroke events for baseline TQoL was 0.93 (95% confidence interval, 0.89-0.98) per 0.1 U increase. The lowest baseline TQoL quartile had a 20% increased stroke risk (hazard ratio=1.20 [95% confidence interval, 1.00-1.44]) compared with the reference highest quartile TQoL. Poststroke TQoL change was significant within all treatment groups (P≤0.001). Multivariate regression analysis revealed that baseline TQoL was the strongest predictor of poststroke TQoL with similar results for the untransformed QoL. CONCLUSIONS: The lowest baseline TQoL quartile had a 20% higher stroke risk than the highest quartile. Baseline TQoL was the only factor that predicted poststroke change in TQoL. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000542.

Use of Repeated Blood Pressure and Cholesterol Measurements to Improve Cardiovascular Disease Risk Prediction: An Individual-Participant-Data Meta-Analysis.

The added value of incorporating information from repeated blood pressure and cholesterol measurements to predict cardiovascular disease (CVD) risk has not been rigorously assessed. We used data on 191,445 adults from the Emerging Risk Factors Collaboration (38 cohorts from 17 countries with data encompassing 1962-2014) with more than 1 million measurements of systolic blood pressure, total cholesterol, and high-density lipoprotein cholesterol. Over a median 12 years of follow-up, 21,170 CVD events occurred. Risk prediction models using cumulative mean values of repeated measurements and summary measures from longitudinal modeling of the repeated measurements were compared with models using measurements from a single time point. Risk discrimination (C-index) and net reclassification were calculated, and changes in C-indices were meta-analyzed across studies. Compared with the single-time-point model, the cumulative means and longitudinal models increased the C-index by 0.0040 (95% confidence interval (CI): 0.0023, 0.0057) and 0.0023 (95% CI: 0.0005, 0.0042), respectively. Reclassification was also improved in both models; compared with the single-time-point model, overall net reclassification improvements were 0.0369 (95% CI: 0.0303, 0.0436) for the cumulative-means model and 0.0177 (95% CI: 0.0110, 0.0243) for the longitudinal model. In conclusion, incorporating repeated measurements of blood pressure and cholesterol into CVD risk prediction models slightly improves risk prediction.

Hydroxycarbamide versus chronic transfusion for maintenance of transcranial doppler flow velocities in children with sickle cell anaemia-TCD With Transfusions Changing to Hydroxyurea (TWiTCH): a multicentre, open-label, phase 3, non-inferiority trial.

BACKGROUND: For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions. METHODS: TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada. We enrolled children with sickle cell anaemia who were aged 4-16 years and had abnormal TCD flow velocities (≥ 200 cm/s) but no severe vasculopathy. After screening, eligible participants were randomly assigned 1:1 to continue standard transfusions (standard group) or hydroxycarbamide (alternative group). Randomisation was done at a central site, stratified by site with a block size of four, and an adaptive randomisation scheme was used to balance the covariates of baseline age and TCD velocity. The study was open-label, but TCD examinations were read centrally by observers masked to treatment assignment and previous TCD results. Participants assigned to standard treatment continued to receive monthly transfusions to maintain 30% sickle haemoglobin or lower, while those assigned to the alternative treatment started oral hydroxycarbamide at 20 mg/kg per day, which was escalated to each participant's maximum tolerated dose. The treatment period lasted 24 months from randomisation. The primary study endpoint was the 24 month TCD velocity calculated from a general linear mixed model, with the non-inferiority margin set at 15 cm/s. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, number NCT01425307. FINDINGS: Between Sept 20, 2011, and April 17, 2013, 159 patients consented and enrolled in TWiTCH. 121 participants passed screening and were then randomly assigned to treatment (61 to transfusions and 60 to hydroxycarbamide). At the first scheduled interim analysis, non-inferiority was shown and the sponsor terminated the study. Final model-based TCD velocities were 143 cm/s (95% CI 140-146) in children who received standard transfusions and 138 cm/s (135-142) in those who received hydroxycarbamide, with a difference of 4·54 (0·10-8·98). Non-inferiority (p=8·82 × 10(-16)) and post-hoc superiority (p=0·023) were met. Of 29 new neurological events adjudicated centrally by masked reviewers, no strokes were identified, but three transient ischaemic attacks occurred in each group. Magnetic resonance brain imaging and angiography (MRI and MRA) at exit showed no new cerebral infarcts in either treatment group, but worsened vasculopathy in one participant who received standard transfusions. 23 severe adverse events in nine (15%) patients were reported for hydroxycarbamide and ten serious adverse events in six (10%) patients were reported for standard transfusions. The most common serious adverse event in both groups was vaso-occlusive pain (11 events in five [8%] patients with hydroxycarbamide and three events in one [2%] patient for transfusions). INTERPRETATION: For high-risk children with sickle cell anaemia and abnormal TCD velocities who have received at least 1 year of transfusions, and have no MRA-defined severe vasculopathy, hydroxycarbamide treatment can substitute for chronic transfusions to maintain TCD velocities and help to prevent primary stroke. FUNDING: National Heart, Lung, and Blood Institute, National Institutes of Health.

Association between chronic kidney disease and cancer mortality: A report from the ALLHAT.

BACKGROUND/OBJECTIVES: Chronic kidney disease (CKD) and cancer are both common in older patients; whether CKD increases risk for cancer is unclear. This study evaluated CKD as a risk factor for cancer mortality in a large cohort of hypertensive patients. STUDY DESIGN: We did post-hoc analyses of in-trial and post-trial data from participants in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). SETTING AND PARTICIPANTS: Participants were ≥ 55 years old with hypertension and one other additional risk factor for coronary heart disease. PREDICTOR: Baseline estimated glomerular filtration rate (eGFR). OUTCOMES: Cancer mortality was ascertained by cancer-related deaths reported in national databases during and after the trial. Cox proportional hazard models were used to calculate hazard ratios (HRs) adjusted for possible confounders and were stratified by baseline GFR. RESULTS: Participants' mean age was 66.9 years. After a mean follow-up of 8.9 years, there were 2,338 reported cancer-related deaths. Participants with GFR < 45 mL/min/1.73 m2 were at increased risk of cancer mortality compared to those with GFR ≥ 90 mL/min/1.73 m2 (adjusted HR 1.54 (1.22 - 1.94), p-value for trend 0.004). These findings were consistent across subgroups defined by race, gender, and diabetes. Participants with GFR < 45 mL/min/1.73 m2 were at higher risk for mortality related to colon cancer (p-value for trend 0.048, HR 2.28 (1.12 - 4.62)) and urinary tract cancer (p-value for trend 0.001, adjusted HR 2.95 (1.14 - 7.65)). LIMITATIONS: This is a post hoc analysis of clinical trial data. CONCLUSIONS: In a large cohort of hypertensive patients, GFR < 45 mL/min/1.73 m2 was associated with a higher risk of cancer-related mortality.

Using Bayesian Adaptive Trial Designs for Comparative Effectiveness Research: A Virtual Trial Execution.

BACKGROUND: Bayesian and adaptive clinical trial designs offer the potential for more efficient processes that result in lower sample sizes and shorter trial durations than traditional designs. OBJECTIVE: To explore the use and potential benefits of Bayesian adaptive clinical trial designs in comparative effectiveness research. DESIGN: Virtual execution of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) as if it had been done according to a Bayesian adaptive trial design. SETTING: Comparative effectiveness trial of antihypertensive medications. PATIENTS: Patient data sampled from the more than 42 000 patients enrolled in ALLHAT with publicly available data. MEASUREMENTS: Number of patients randomly assigned between groups, trial duration, observed numbers of events, and overall trial results and conclusions. RESULTS: The Bayesian adaptive approach and original design yielded similar overall trial conclusions. The Bayesian adaptive trial randomly assigned more patients to the better-performing group and would probably have ended slightly earlier. LIMITATIONS: This virtual trial execution required limited resampling of ALLHAT patients for inclusion in RE-ADAPT (REsearch in ADAptive methods for Pragmatic Trials). Involvement of a data monitoring committee and other trial logistics were not considered. CONCLUSION: In a comparative effectiveness research trial, Bayesian adaptive trial designs are a feasible approach and potentially generate earlier results and allocate more patients to better-performing groups. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute.

The Impact of Antihypertensive Medications on Bone Mineral Density and Fracture Risk.

PURPOSE OF REVIEW: This review summarizes the impact of thiazide diuretics on fracture risk in older hypertensive individuals. RECENT FINDINGS: We performed a post hoc evaluation of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial, a randomized, prospective, double blind hypertension study comparing a thiazide-like diuretic, a calcium channel blocker (CCB), and an angiotensin converting enzyme inhibitor (ACEi). We examined the risk of hip and pelvic fractures during the in-trial period (n = 22,180 participants; mean 4.9-year follow-up) and during the post-trial period using national data bases (n = 16,622 participants) (mean total follow-up 7.8 years). During the trial, participants randomized to the thiazide diuretic versus the CCB or the ACEi had a lower risk of fracture on adjusted analyses (HR 0.79 [95% CI, 0.63, 0.98], p = 0.04). Risk of fracture was significantly lower in participants randomized to the diuretic as compared to those randomized to the ACEi (HR 0.75 [95% CI, 0.58, 0.98]; p = 0.04), but not significantly different compared to the CCB (HR 0.87 [95% CI, 0.71, 1.09]; p = 0.17). Over the entire trial and post-trial period of follow-up, the cumulative incidence of fractures was non-significantly lower in participants assigned to the diuretic vs assignment to the ACEi or the CCB (HR 0.87 [0.74-1.03], p = 0.10) and versus each medication separately. These findings establish a benefit for thiazide diuretic treatment for the prevention of fractures versus other commonly used antihypertensive medications using prospective, randomized data. The effects of the thiazide diuretic on bone appear to be long lasting.