Analysis of published economic evaluations of angiotensin receptor blockers.

Introduction: In this study we reviewed the published literature on the economic evaluation of the use of angiotensin receptor blockers (ARBs) for the treatment of hypertension, either primary or due to diabetes.

Methods: An extensive literature review was undertaken. The HEED (Health Economic Evaluations Database) of the Office for Health Economics and the NHS-EED (NHS Economic Evaluation Database) databases were searched. Keywords used were "losartan", "irbesartan", "valsartan", "candesartan", "olmesartan", "telmisartan", "eprosartan", "primary hypertension" and "diabetes". The study included all articles retrieved from 2001 onwards. Exclusion criteria included economic evaluations of ARBs for other indications (e.g. heart failure, myocardial infarction, etc.), an underage population, as well as prevalence studies of hypertension for a disease-specific population.

Results: Of the 63 studies retrieved in the literature search, 35 were included in the review. The majority of the studies were of irbesartan (16) or losartan (8). In each study, the model used country-specific data to project and evaluate the clinical and cost outcomes of the treatment arms. The most common method undertaken was cost-consequence analysis (52.94%) followed by cost-effectiveness analysis (32.35%). In most cases, costs and benefits results were not synthesised. Results failed to show a clear advantage in favour of specific therapy, as the outcomes suffered from heterogeneity, referred to specific circumstances and were rather difficult to compare. For different treatment comparators, all the analyses demonstrated an improved life expectancy and a cost-saving choice. The robustness of results was tested with a series of sensitivity analyses, which showed a statistically significant result in each case.

Conclusions: The evidence from this review suggests that the available ARBs represent a cost-saving and cost-effective treatment compared with other conventional treatment options for patients with hypertension and associated conditions. However, there are no meaningful differences between available ARBs, as the design of clinical and economic studies makes it difficult to find any such differences.