Primary Outcome Meta-analysis: Effect of placebo and diuretic on plasma aldosterone
Placebo had a negligible effect on PA in the present analysis (Fig 2D). Standardized difference in mean PA after placebo was -0.11 (95% CI -0.36, 0.14). With diuretic therapy, all diuretic classes led to a significant increase in PA but there was no between-class heterogeneity (Fig 2A). The average standardised difference in mean PA change was: thiazide/thiazide-like 0.304 (0.169, 0.440), loop 0.927 (0.37, 1.49), MRA/potassium-sparing 0.264 (0.174, 0.355) and combination 0.466 (0.142, 0.789), Q = 6.475, P = 0.091. In studies where there was no background antihypertensive use/a washout, the average increase in PA was 0.392 (0.234, 0.550, Figure 2B). There was a similar, increase in PA for those in whom diuretic was added to previous antihypertensives: 0.300 (0.046, 0.553, Figure 2C). After separating MRA from potassium-sparing diuretics, the same homogeneity between classes was found.