High prevalence and a long delay in the diagnosis of primary aldosteronism among patients with young‐onset hypertension
Sarah Alam, Devasenathipathy Kandasamy, Alpesh Goyal, Sreenivas Vishnubhatla, Sandeep Singh, Ganesan Karthikeyan, Rajesh Khadgawat
Abstract
BACKGROUND: Despite being the most common cause of secondary hypertension, prevalence of primary aldosteronism (PA) among patients with young-onset hypertension (YH - age of hypertension onset <40 years) remains poorly studied. OBJECTIVE: We assessed the prevalence of PA in patients with YH referred for evaluation of secondary hypertension. DESIGN AND PATIENTS: In this prospective, cross-sectional study, 202 patients with YH, visiting endocrine and cardiology clinics of All India Institute of Medical Sciences, India, were evaluated. MEASUREMENTS: Primary aldosteronism was screened by measuring plasma aldosterone concentration (PAC) and direct renin concentration (DRC) and calculating aldosterone-to-renin ratio (ARR), followed by confirmatory saline infusion test (SIT) according to Endocrine Society Guideline. Those confirmed with post-SIT PAC >5 ng/dl underwent adrenal computed tomography (CT), followed by adrenal venous sampling (AVS). RESULTS: Of 202 YH patients, 38 (18.8%) screened positive, and PA was confirmed in 36 (17.8%). The mean age was 43.9 ± 10.9 years, and median duration of hypertension was 10.5 (3.5-18) years. The prevalence of PA increased with grade of hypertension (8.1% in grade 1 to 37.1% in grade 3), number of antihypertensive medications (2.5% in those taking ≤1 to 50% in those taking ≥4 medications) and severity of hypokalaemia (0% in potassium >5 to 85.7% in potassium <3.5 mmol/L). The prevalence of PA by age of hypertension onset was highest in age group 30-39 years (31.3%). CONCLUSIONS: There is a high prevalence and a long delay in diagnosis of PA among patients with YH, and YH should be considered as a separate high-risk category in PA screening algorithm.