Influence of orthostatic blood pressure changes on the effects of intensive blood pressure control in patients with type 2 diabetes

Abstract Background Intensive blood pressure (BP) control has been proven to reduce the risks of major cardiovascular diseases (CVD) in patients with type 2 diabetes mellitus (T2DM) (1). Excessive orthostatic BP changes should be fully addressed, given its high prevalence and associations with adverse events among T2DM patients (2-5). However, the benefits of intensive BP control among T2DM patients with significant orthostatic BP changes have been equivocal. Purpose To examine whether orthostatic BP changes modify the efficacy of intensive BP control on CVD outcomes in patients with T2DM. Methods The Action to Control Cardiovascular Risk in Diabetes Blood Pressure trial (ACCORD BP) is a 2×2 factorial designed trial that aimed to evaluate the effects of intensive glycemia and BP control on major CVD events among T2DM patients (6). We enrolled participants with at least one record of orthostatic BP values for analysis. The composite CVD outcome in this study comprised cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, and hospitalized congestive heart failure. Associations between orthostatic BP changes and the composite CVD outcome and all-cause death, respectively, were presented by restricted cubic spline curves based on multivariable Cox models. We examined if the effects of intensive BP control varied across the orthostatic BP change for the composite CVD outcome and all-cause death. Results Among 4330 participants, 877 (20.3%) experienced episodes of orthostatic hypotension (OH) at baseline or during follow-up. There was no significant difference in the proportions of OH participants between the intensive and standard BP arms. U-shaped associations were observed between orthostatic systolic BP changes and the composite CVD outcome, as well as all-cause mortality (Figure 1). In the standard glycemia arm, intensive BP control was significantly associated with a lower risk of composite CVD outcome (HR 0.76, 95%CI 0.59-0.97). There was a beneficial association of intensive BP control with all-cause mortality without statistical significance (HR 0.85, 95%CI 0.56-1.30). The favorable effect of intensive BP control was not influenced by orthostatic BP changes (P for interaction 0.51 for the composite CVD outcome and 0.97 for all-cause mortality) (Figure 2). Beneficial effects of intensive BP control were not observed for participants in the intensive glycemia arm on the composite CVD outcome (HR 0.99, 95%CI 0.76-1.28) and all-cause mortality (HR 1.19, 0.79-1.80). Conclusion Orthostatic BP changes should not be a barrier to intensive BP control for T2DM patients treated with guideline-recommended standard glycemia control.