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Aims: Patients with heart failure usually have several other medical conditions that might alter the effects of interventions. We investigated whether the burden of comorbidity modified the clinical response to cardiac resynchronization therapy (CRT). Methods and results: Original patient‐level data from eight randomized trials exploring the effects of CRT versus no CRT were pooled (BLOCK‐HF, MIRACLE, MIRACLE‐ICD, MIRACLE‐ICD II, RAFT, COMPANION, MADIT‐CRT and REVERSE). A prior history of the following comorbidities was considered: episodic or persistent atrial fibrillation (n = 920), coronary artery disease (n = 3732), diabetes (n = 2171), and hypertension (n = 3353). Patients were classified into three groups based on the number of comorbidities: 0, 1–2, or ≥3. The outcomes of interest were time to all‐cause mortality and time to the composite outcome of heart failure hospitalization (HFH) or all‐cause mortality. Outcomes were evaluated within each comorbidity group using a Bayesian hierarchical Weibull survival regression model. Of 6324 patients, 970 (15%) had no comorbidities, 4052 (64%) had 1–2 and 1302 (21%) had ≥3 comorbidities. The adjusted hazard ratio (aHR) for CRT versus no CRT for all‐cause mortality in the overall cohort was 0.79 (95% credible interval [CI] 0.68–0.93) (p = 0.010); for no comorbidities the aHR was 0.54 (95% CI 0.34–0.86), for 1–2 comorbidities was 0.81 (95% CI 0.67–0.97) and for ≥3 comorbidities was 0.83 (95% CI 0.64–1.07) (no significant interaction between CRT and comorbidity burden: p = 0.13). For the endpoint of HFH or all‐cause mortality, the aHR for the overall cohort was 0.74 (95% CI 0.65–0.84) (p = 0.001), for no comorbidities was 0.69 (95% CI 0.50–0.94), for 1–2 comorbidities was 0.77 (95% CI 0.66–0.90) and for ≥3 comorbidities was 0.68 (95% CI 0.55–0.82) (no significant interaction between CRT and comorbidity burden: p = 0.081). Conclusion: In a meta‐analysis of patient‐level data from eight major trials, the totality of evidence suggests that CRT reduces HFH and/or all‐cause mortality even when several comorbid diseases are present. Clinical Trial Registration: NCT00271154, NCT00251251, NCT00267098, NCT00180271. [ABSTRACT FROM AUTHOR]

Background: Cluster-randomized trials (CRTs) are being increasingly used to test a range of interventions, including medical interventions commonly used in clinical practice. Policies created by the NIH and the Food and Drug Administration (FDA) require the reporting of demographics and the examination of demographic heterogeneity of treatment effect (HTE) for individually randomized trials. Little is known about how frequent demographics are reported and HTE analyses are conducted in CRTs. Objectives: We sought to understand the prevalence of HTE analyses and the statistical methods used to conduct them in CRTs focused on treating cardiovascular disease, cancer, and chronic lower respiratory diseases. Additionally, we also report on the proportion of CRTs that reported on baseline demographics of its populations and conducted demographic HTE analyses. Data sources: We searched PubMed and Embase for CRTs published between 1/1/2010 and 3/29/2016 that focused on treating the top 3 Center for Disease Control causes of death (cardiovascular disease, chronic lower respiratory disease, and cancer). Evidence Screening And Review: Of 1,682 unique titles, 117 abstracts were screened. After excluding 53 articles, we included 64 CRT publications and abstracted information on study characteristics and demographic information, statistical analysis, HTE analysis, and study quality. Results: Age and sex were reported in greater than 95.3% of CRTs, while race and ethnicity were reported in only 20.3% of CRTs. HTE analyses were conducted in 28.1% (n = 18) of included CRTs and 77.8% (n = 12) were prespecified analyses. Four CRTs conducted a demographic subgroup analysis. Only 6/18 CRTs used interaction testing to determine whether HTE existed. Conclusions: Baseline demographic reporting was high for age and sex in CRTs, but was uncommon for race and ethnicity. HTE analyses were uncommon and was rare for demographic subgroups, which limits the ability to examine the extent of benefits or risks for treatments tested with CRT designs. [ABSTRACT FROM AUTHOR]

Background: The optimal treatment for latent multiple-drug resistant tuberculosis infection remains unclear. In anticipation of future clinical trials, we modeled the expected performance of six potential regimens for treatment of latent multipledrug resistant tuberculosis. Methods: A computerized Markov model to analyze the total cost of treatment for six different regimens: Pyrazinamide/ ethambutol, moxifloxacin monotherapy, moxifloxacin/pyrazinamide, moxifloxacin/ethambutol, moxifloxacin/ethionamide, and moxifloxacin/PA-824. Efficacy estimates were extrapolated from mouse models and examined over a wide range of assumptions. Results: In the base-case, moxifloxacin monotherapy was the lowest cost strategy, but moxifloxacin/ethambutol was costeffective at an incremental cost-effectiveness ratio of $21,252 per quality-adjusted life-year. Both pyrazinamide-containing regimens were dominated due to their toxicity. A hypothetical regimen of low toxicity and even modest efficacy was costeffective compared to ''no treatment.'' Conclusion: In our model, moxifloxacin/ethambutol was the preferred treatment strategy under a wide range of assumptions; pyrazinamide-containing regimens fared poorly because of high rates of toxicity. Although more data are needed on efficacy of treatments for latent MDR-TB infection, data on toxicity and treatment discontinuation, which are easier to obtain, could have a substantial impact on public health practice. [ABSTRACT FROM AUTHOR]

Rationale: Rifapentine-based regimens for treating latent tuberculosis infection (LTBI) are being considered for future clinical trials, but even if they prove effective, high drug costs may limit their economic viability. Objectives: To inform clinical trial design by estimating the potential costs and effectiveness of rifapentine-based regimens for treatment of latent tuberculosis infection (LTBI). Methods: We used a Markov model to estimate cost and societal benefits for three regimens for treating LTBI: Isoniazid/ rifapentine daily for one month, isoniazid/rifapentine weekly for three months (self-administered and directly-observed), and isoniazid daily for nine months; a strategy of ''no treatment'' used for comparison. Costs, quality-adjusted life-years gained, and instances of active tuberculosis averted were calculated for all arms. Results: Both daily isoniazid/rifapentine for one month and weekly isoniazid/rifapentine for three months were less expensive and more effective than other strategies under a wide variety of clinically plausibly parameter estimates. Daily isoniazid/rifapentine for one month was the least expensive and most effective regimen. Conclusions: Daily isoniazid/rifapentine for one month and weekly isoniazid/rifapentine for three months should be studied in a large-scale clinical trial for efficacy. Because both regimens performed well even if their efficacy is somewhat reduced, study designers should consider relaxing non-inferiority boundaries. [ABSTRACT FROM AUTHOR]

ICD: Remote Monitoring Versus Clinic Interrogations. Introduction: Remote monitoring is increasingly becoming the new standard of care for implantable cardioverter defibrillator (ICD) follow-up. We sought to determine whether remote monitoring of ICDs improves patient outcomes compared with quarterly device interrogations in clinic. Methods and Results: In this single-center pilot clinical trial, adult patients with an ICD were randomly assigned to remote monitoring versus quarterly device interrogations in clinic. The primary endpoint was a composite of cardiovascular hospitalization, emergency room visit for a cardiac cause, and unscheduled visit to the electrophysiology clinic for a device-related issue at 1 year. We also examined health-related quality of life, costs, and patient satisfaction with their ICD care. Of 151 patients enrolled in this trial, 76 were randomized to remote monitoring and 75 to quarterly device interrogations in clinic. There was no significant difference in the primary endpoint (32% in the remote monitoring arm vs 34% in the control arm; P = 0.8), mortality, or cost between the 2 arms. Quality of life and patient satisfaction were significantly better in the control arm than in the remote monitoring arm at 6 months (83 [25th, 75th percentiles 70, 90] vs 75 [50, 85]; P = 0.002 and 88 [75, 100] vs 75 [75, 88]; P = 0.03, respectively), but not at 12 months. Conclusion: We showed no significant reduction in cardiac-related resource utilization with remote monitoring of ICDs. However, given the small number of patients in our study, the real clinical and health economics impact of remote monitoring needs to be verified by a large, multicenter, randomized clinical trial. (J Cardiovasc Electrophysiol, Vol. 21, pp. 545-550, May 2010) [ABSTRACT FROM AUTHOR]

The implantable cardioverter defibrillator (ICD) is a costly new treatment for patients at high risk of sudden cardiac death. Randomized trials of the ICD showed it to be effective in some groups of patients but not in others. While new trials testing the ICD were ongoing to clarify the evidence, policymakers faced immediate decisions about providing insurance coverage for the device. The high cost of ICDs, the large population of patients potentially eligible to receive them, the potential to reduce preventable deaths, and the unsettled state of the medical evidence provided a challenge to evidence-based medicine and to policymakers. [ABSTRACT FROM AUTHOR]

Human papillomavirus (HPV) has been implicated as the primary etiologic agent of cervical cancer. Potential vaccines against high-risk HPV types are in clinical trials. We evaluated vaccination programs with a vaccine against HPV-16 and HPV-18. We developed disease transmission models that estimated HPV prevalence and infection rates for the population overall, by age group, by level of sexual activity within each age group, and by sex. Data were based on clinical trials and published and unpublished sources. An HPV-16/18 vaccine for 12-year-old girls would reduce cohort cervical cancer cases by 61.8%, with a cost-effectiveness ratio of $14,583 per quality-adjusted life year (QALY). Including male participants in a vaccine rollout would further reduce cervical cancer cases by 2.2% at an incremental cost-effectiveness ratio of $442,039/QALY compared to female-only vaccination. Vaccination against HPV-16 and HPV-18 can be cost-effective, although including male participants in a vaccination program is generally not cost-effective, compared to female-only vaccination. [ABSTRACT FROM AUTHOR]

Background: Eight randomized trials have evaluated whether the prophylactic use of an implantable cardioverter–defibrillator (ICD) improves survival among patients who are at risk for sudden death due to left ventricular systolic dysfunction but who have not had a life-threatening ventricular arrhythmia. We assessed the cost-effectiveness of the ICD in the populations represented in these primary-prevention trials. Methods: We developed a Markov model of the cost, quality of life, survival, and incremental cost-effectiveness of the prophylactic implantation of an ICD, as compared with control therapy, among patients with survival and mortality rates similar to those in each of the clinical trials. We modeled the efficacy of the ICD as a reduction in the relative risk of death on the basis of the hazard ratios reported in the individual clinical trials. Results: Use of the ICD increased lifetime costs in every trial. Two trials — the Coronary Artery Bypass Graft (CABG) Patch Trial and the Defibrillator in Acute Myocardial Infarction Trial (DINAMIT) — found that the prophylactic implantation of an ICD did not reduce the risk of death and thus was both more expensive and less effective than control therapy. For the other six trials — the Multicenter Automatic Defibrillator Implantation Trial (MADIT) I, MADIT II, the Multicenter Unsustained Tachycardia Trial (MUSTT), the Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial, the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION) trial, and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) — the use of an ICD was projected to add between 1.01 and 2.99 quality-adjusted life-years (QALY) and between $68,300 and $101,500 in cost. Using base-case assumptions, we found that the cost-effectiveness of the ICD as compared with control therapy in these six populations ranged from $34,000 to $70,200 per QALY gained. Sensitivity analyses showed that this cost-effectiveness ratio would remain below $100,000 per QALY as long as the ICD reduced mortality for seven or more years. Conclusions: Prophylactic implantation of an ICD has a cost-effectiveness ratio below $100,000 per QALY gained in populations in which a significant device-related reduction in mortality has been demonstrated. N Engl J Med 2005;353:1471-80. [ABSTRACT FROM AUTHOR]