Impact of Age, Sex, and Race on Primary Aldosteronism Test Interpretations

New guidelines recommend testing for primary aldosteronism (PA) in all people with hypertension. Interpreting population-based results for PA will require understanding the influence of demographic characteristics.

858 adults from across the US meeting traditional guideline criteria for PA testing underwent testing. The influence of demographic factors on test result interpretations was assessed after multivariable adjustment.

Mean age was 62±11 years, with 54.6% women, 14% Black, and 22.9% Hispanic. Independent of antihypertensive medications and clinical comorbidities, participants aged ≥70 years had 24% lower aldosterone (P<0.05), 48% lower renin activity (P<0.001), and trended toward higher aldosterone-to-renin ratio (52% higher; P=0.14), compared with those <50 years. Aldosterone levels were higher in women compared with men across the lifespan. Black participants had 81% higher aldosterone-to-renin ratio than White participants (P<0.001), primarily due to lower renin (P<0.005). These demographic factors influenced the ultimate PA testing interpretation: participants ≥70 years old had 19% higher odds of a positive test than those <50 years old (P=0.002), and Black participants had 22% higher odds of a positive test than White participants (P<0.001).

In this large, diverse, nationwide sample, older and Black participants had higher aldosterone-to-renin ratio and higher odds of testing positive for PA, and women had higher aldosterone levels than men across the lifespan. With newly expanded indications for PA testing, a greater appreciation of the influence of demographic characteristics on PA test results will be required.