OBJECTIVE: There is little evidence on comparative effectiveness of individual angiotensin receptor blockers (ARBs) in patients with chronic heart failure (CHF). This study compared four ARBs in reducing risk of mortality in clinical practice.
METHODS: A retrospective analysis was conducted on a national sample of patients diagnosed with CHF from 1 October 1996 to 30 September 2002 identified from Veterans Affairs electronic medical records, with supplemental clinical data obtained from chart review. After excluding patients with exposure to ARBs within the previous 6 months, four treatment groups were defined based on initial use of candesartan, valsartan, losartan, and irbesartan between the index date (1 October 2000) and the study end date (30 September 2002). Time to death was measured concurrently during that period. A marginal structural model controlled for sociodemographic factors, comorbidities, comedications, disease severity (left ventricular ejection fraction), and potential time-varying confounding affected by previous treatment (hospitalization). Propensity scores derived from a multinomial logistic regression were used as inverse probability of treatment weights in a generalized estimating equation to estimate causal effects.
RESULTS: Among the 1536 patients identified on ARB therapy, irbesartan was most frequently used (55.21%), followed by losartan (21.74%), candesartan (15.23%), and valsartan (7.81%). When compared with losartan, after adjusting for time-varying hospitalization in marginal structural model, candesartan (OR = 0.79, 95%CI = 0.42-1.50), irbesartan (OR = 1.17, 95%CI = 0.72-1.90), and valsartan (OR = 0.98, 95%CI = 0.45-2.14) were found to have similar effectiveness in reducing mortality in CHF patients.
CONCLUSION: Effectiveness of ARBs in reducing mortality is similar in patients with CHF in everyday clinical practice.
BACKGROUND: Introduction of biologic disease-modifying antirheumatic drugs (DMARDs) has considerably changed treatment options for rheumatoid arthritis (RA) over the past decade. Very little information is available on comparative discontinuation rates of the biologics.
OBJECTIVE: To compare treatment discontinuations for 9 biologic DMARDs in adults with RA.
METHODS: We searched electronic databases through May 2012 to retrieve randomized controlled trials (RCTs) of patients with RA that compared biologic DMARDs with placebo or another biologic DMARD. The primary outcome was treatment discontinuation during the blinded phase of the trials, measured as overall withdrawals, withdrawals resulting from lack of efficacy, and withdrawals resulting from adverse events. Random-effects meta-analysis estimated the effect size for individual agents, and adjusted indirect comparisons were made between biologics using mixed treatment comparisons (MTC) meta-analysis.
RESULTS: Forty-four trials were included in the analysis. In comparison with placebo, biologics were less likely to be withdrawn because of lack of efficacy (OR 0.22, 95% CI 0.17 to 0.27) and more likely to be withdrawn because of an adverse event (OR 1.41, 95% CI 1.16 to 1.70). Based on the MTC, certolizumab had the most favorable overall withdrawal profile, followed by etanercept and rituximab. Certolizumab had lower relative withdrawal rates resulting from lack of efficacy than adalimumab, anakinra, and infliximab. Anakinra had higher relative withdrawal rates resulting from lack of efficacy than most other biologics. Certolizumab and infliximab had more, while etanercept had fewer, withdrawals because of adverse events than most other drugs.
CONCLUSIONS: Based on MTC using data from RCTs, differences in discontinuation rates were observed, generally favoring certolizumab, etanercept, and rituximab over other biologic DMARDs. These potential differences need to be further explored in head-to-head trials or well-conducted observational studies.