Heart failure and the discrepancy between trials of intensive blood pressure management: an analysis of individual patient data.

BACKGROUND: ACCORD and SPRINT are the best randomized controlled trial data evaluating the effects of blood pressure targets below 140 mmHg. These trials had contradictory results regarding the benefits of intensive antihypertensive therapy. We investigate if this discordance was driven by SPRINT's inclusion of Heart Failure in its primary outcome, as this is a parameter not included in ACCORD's original primary outcome. This analysis helps to resolve a significant area of contention.

METHODS: Individual patient data from 4733 participants in ACCORD were analyzed from time of randomization. All participants were diabetic and at increased cardiovascular risk. Participants were assigned to their original intervention, a standard blood pressure target of less than 140 mmHg or an intensive target of less than 120 mmHg. Primary composite outcome was defined as in SPRINT: a composite of first occurrence of myocardial infarction, stroke, heart failure, death from cardiovascular causes, and other acute coronary syndromes.

RESULTS: Primary outcome was not significantly different between standard and intensive groups [HR: 0.89; 95% CI: (0.76-1.03); p = 0.108]. The primary composite outcome occurred in 370 participants in the standard group (15.6%) and 324 participants in the intensive group (13.7%), with an event rate of 3.38% per year for the standard group and 3.01% per year for the intensive group.

CONCLUSIONS: Differing results between ACCORD and SPRINT are not attributable to ACCORD's exclusion of Heart Failure from its original primary outcome measurement. No significant differences in primary outcome were observed between intensive and standard blood pressure groups in the ACCORD patients under the SPRINT primary outcome definition. Caution should be taken in extrapolating the intensive blood pressure control benefits of SPRINT to the diabetic population.