Background:
The renin-angiotensin-aldosterone system (RAAS) is an important driver of BP but the association of the RAAS with ambulatory blood pressure (ABP) and ABPM phenotypes among African Americans (AA) has not been assessed.
Methods:
ABP and ABPM phenotypes were assessed in 912 Jackson Heart Study participants with aldosterone and plasma renin activity (PRA). Multivariable linear and logistic regression analysis were used to analyze the association of aldosterone, and PRA with clinic, awake and asleep systolic blood pressure (SBP) and diastolic blood pressure (DBP) and ABPM phenotypes, adjusting for important confounders.
Results:
The mean age of participants was 59 ±11 years and 69% were female. In fully adjusted models, lower log-PRA was associated with higher clinic, awake, and asleep SBP and DBP (all p<0.05). A higher log-aldosterone was associated with higher clinic, awake, and asleep DBP (all p<0.05). A 1-unit higher log-PRA was associated with lower odds of daytime hypertension (OR: 0.59, 95%CI: 0.49, 0.71), nocturnal hypertension (OR: 0.68, 95%CI: 0.58, 0.79), daytime and nocturnal hypertension (OR: 0.59, 95%CI: 0.48, 0.71), sustained hypertension (OR: 0.52, 95%CI: 0.39, 0.70) and masked hypertension (OR 0.75, 95%CI: 0.62, 0.90). A 1-unit higher log-aldosterone was associated with higher odds of nocturnal hypertension (OR: 1.38, 95%CI: 1.05, 1.81). Neither PRA nor aldosterone were associated with percent dipping, non-dipping BP pattern, or white-coat hypertension. Patterns for aldosterone:renin ratio were similar to PRA.
Conclusions:
Suppressed renin activity and higher aldosterone:renin ratios were associated with both higher SBP and DBP in the office and during the awake and asleep periods as evidenced by ABPM. Higher aldosterone levels were associated with higher DBP, but not SBP, in the clinic and during the awake and asleep periods. Further clinical investigation of novel and approved medications that target low renin physiology such as epithelial sodium channel inhibitors and mineralocorticoid receptor antagonists may be paramount in improving hypertension control in AAs.