Endocrine Abstracts

Background: Primary aldosteronism (PA) is the most frequent form of secondary hypertension, with a high prevalence in resistant hypertension (RH), a condition of insufficient blood pressure (BP) control despite a 3-drug based treatment at full dose, including a diuretic. The prevalence of PAin refractory hypertension (ReH), a condition of persistently elevated BP values despite therapy with 5 drugs, is not known.

Objective: To investigate the prevalence of PA in RH and ReH and its association with cardiometabolic complications, atrial fibrillation (AF) and aortic ectasia.

Subjects and Methods: We enrolled consecutive patients with RHand without previous cardiovascular events, referred to our Center for Hypertension, Division of Endocrinology, Diabetes and Metabolism, University of Turin, between 09/2011 and 09/2019. PA was diagnosed when the following conditions were met: PAC > 150 pg/ml, PRA < 1 ng/ml per hour, ARR > 400 and PAC after SIT > 100 pg/ml.

Results: 110 patients with RH were enrolled. PA was diagnosed in 32 cases (29.1%). In univariate analysis, PA patients was associated to male gender, hypokalemia, worse hypertensive profile, single and cumulative organ damage (OD) (microalbuminuria, chronic kidney disease, carotid Intima Media Thickness andLeft Ventricular Hypertrophy), aortic ectasia and atrial fibrillation. The multivariate analysis showed that PAis a strong factor associated with left ventricular hypertrophy (OR = 13.13, 95% CI 3.79-62.70; P < 0.001), microalbuminuria (OR = 3.77, 95% CI 1.45–10.21; P = 0.007), carotid intima-media thickness (cIMT) ≥ 0.9 mm (OR = 2.81, 95% CI 1.02–8.19; P = 0.049), aortic ectasia (OR = 7.93, 95% CI 2.09–52.36; P = 0.008) and atrial fibrillation (OR 8.54, 95% CI 1.53–70.77; P = 0.022). Moreover, PA was independently associated with the presence of at least one type (OR = 8.60, 95% CI 1.73–69.88; P = 0.018) and at least two types of OD (OR = 3.08, 95% CI 1.19–8.24; P = 0.022). 13 patients (11.82%) were affected by ReH. This group was characterized by higher valuesof cIMT (1.20, 1.00–1.40 vs 0.70, 0.60–0.90 mm; P = 0.002), higher rate of aldosterone producing adenoma (23.08% vs 6.19%; P = 0.041) and atrial fibrillation (23.08% vs 5.15%; P < 0.049), if compared to the other subjectswith RH.

Conclusions: The present study indicates that primary aldosteronism is a frequent cause ofsecondary hypertension andcardiovascular complications among patients with resistant andrefractory hypertension, suggesting acrucial role of aldosterone in the pathogenesis of severe hypertensive phenotypes and cardiovascular disease. Physicians should not stigmatize the relevance of an ineffective multiple drug antihypertensive therapy and should refer patients with RH to hypertension reference centers, because specific treatment of PA improves OD and reduces the incidence of cardiometabolic complications.