Long-term impact of spironolactone compliance on microalbuminuria in patients with primary aldosteronism

Patients with primary aldosteronism (PA) have a high prevalence of microalbuminuria (MAU), which leads to more severe systemic vascular damage. However, the primary recommended drug treatment for PA, spironolactone (SPL), has had poor patient compliance owing to its adverse effects, and the effect of SPL compliance on MAU has not been fully evaluated in patients with PA. We analyzed the effect of SPL compliance on endothelial dysfunction by assessing MAU in patients with PA. The study included 145 confirmed PA patients who received long-term medical treatment (mean, 5 years). As expected, compliance with SPL treatment improved patients' blood pressure and serum potassium levels. Patients with PA who complied fully with SPL treatment had a lower rate of MAU than noncompliant patients (13.73% versus 34.88%, respectively; P = 0.004). Multivariate logistic regression analyses adjusted for age and sex showed that continuous SPL treatment was associated with a lower presence of MAU (odds ratio, 0.319; 95% confidence interval, 0.135-0.750; P = 0.009). This association remained significant after further adjusting for other major risk factors. However, in the subgroup analysis, the protective effect against MAU was limited in compliant patients treated with >= 40 mg/day SPL compared with noncompliant patients (9.62% versus 34.88%, respectively; P < 0.05). Our findings demonstrated that in addition to improving high blood pressure and hypokalemia, full compliance with the appropriate dose of SPL may benefit endothelial function, as reflected by a lower prevalence of MAU in patients with PA.