Aldosterone levels and renin activity

Aldosterone and PRA were measured two times using competition-based radioimmunoassay (DiaSorin) and radioimmunoassay (DiaSorin), respectively.²² PRA was defined as nanograms of angiotensin I generated per milliliter of sample per hour (ng/mL/h = μg/L/h).²² Aldosterone-renin ratio (ARR) was calculated by dividing aldosterone by PRA. In addition, we dichotomized participants based on PRA; i.e. suppressed renin phenotype, PRA ≤0.5 μg/L/h; intermediate to unsuppressed renin phenotype, PRA >0.5 μg/L/h.¹⁸ We combined intermediate and unsuppressed phenotype to keep statistical power in our main analysis.