Effect of diuretics on plasma aldosterone and potassium in primary
hypertension: A systematic review and meta-analysis
Abstract
Aim: Different to inhibitory drugs of the renin-angiotensin-aldosterone
system (RAAS), diuretics are known to decrease blood pressure (BP) and
stimulate renin release by the kidneys. Despite plasma aldosterone (PA)
level is mostly regulated by the RAAS activity, serum potassium has been
shown to be an important factor in animal models and humans. Here we
perform a systematic review and meta-analysis of randomized-controlled
trials investigating the effects of diuretic therapy on PA and its
correlation with change in potassium and BP. Methods: Three databases
were searched: MEDLINE, EMBASE and The Cochrane Central Register of
Controlled Trials (CENTRAL). Titles were firstly screened by title and
abstract for relevancy before full-text articles were assessed for
eligibility according to a pre-defined inclusion/exclusion criteria.
Results: A total of 1139 articles were retrieved of which 45 met the
pre-specified inclusion/exclusion criteria. The average standardised
difference in mean PA change was similar for all classes of diuretic
(mean, 95% CI); 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 subjects previously
untreated with another antihypertensive, there was a significant
relationship between PA change and change in systolic BP but no
relationship with the change in potassium. Conclusion: In RCTs of
diuretic therapy in hypertension, there is an increase in PA with all
classes of diuretic and no between-class heterogeneity. Change in PA is
not related with potassium but correlates to the change in BP in
subjects previously untreated with another antihypertensive medication.