Purpose Renin profiling has been proposed as a method to guide antihypertensive drug selection. This prespecified post-hoc analysis examined the influence of baseline plasma renin activity (PRA) on blood pressure (BP) responses. Methods A 16-week, randomized, double-blind, promptedtitration trial evaluated initial valsartan (V)/hydrochlorothiazide (HCTZ) combination therapy versus initial HCTZ or V monotherapy in individuals aged ≥70 years with systolic hypertension. Sitting PRA was measured at baseline, Week 4, and Week 16. Subjects were stratified into 2 groups for analysis: low renin (baseline PRA <0.65 ng/mL/h) or normal-high renin (baseline PRA ≥0.65 ng/mL/h). Results PRA data were available in 322/384 subjects: 178 had low PRA and 144 had normal-high PRA. AtWeek 4, V/HCTZ was more effective than HCTZ or V at reducing mean sitting systolic BP (MSSBP), independent of baseline PRA, with reductions of ?16.9, ?12.6, and ?9.5 mmHg, respectively, in low-renin subjects and ?19.4, ?11.5, and ?8.6 mmHg in normal-high renin subjects. Baseline PRA was similar in responders (subjects not uptitrated at Week 4) and nonresponders (subjects uptitrated at Week 4). In responders, the reactive rise in PRA at Week 4 was related to change in MSSBP, with the greatest increases in PRA observed in the V/HCTZ group. Higher baseline PRAwas associated with a greater reactive rise in PRA. Conclusions Baseline PRA is not a useful guide to the BP responses of initial combination V/HCTZ in elderly individuals with systolic hypertension.
- Blood pressure
- Plasma rennin activity