Implementation of a formal sleep center–based screening protocol for primary aldosteronism in patients with obstructive sleep apnea

Abstract

BackgroundThere is a bidirectional association between primary aldosteronism and obstructive sleep apnea, with evidence suggesting that the treatment of primary aldosteronism can reduce obstructive sleep apnea severity. Current guidelines recommend screening for primary aldosteronism in patients with comorbid hypertension and obstructive sleep apnea, identifying potential candidates for treatment. However, emerging data suggest current screening practices are unsatisfactory. Moreover, data regarding the true incidence of primary aldosteronism among this population are limited. This study aimed to assess the primary aldosteronism screening rate among patients with obstructive sleep apnea and hypertension at our institution and estimate the prevalence of primary aldosteronism among this population. MethodsSleep studies conducted at our institution between January and September 2021 were retrospectively reviewed. Adult patients with a sleep study diagnostic of obstructive sleep apnea (respiratory disturbance index ≥5) and a diagnosis of hypertension were included. Patient medical records were reviewed and laboratory data of those with biochemical screening for primary aldosteronism were assessed by an experienced endocrinologist. Screening rates were compared before and after initiation of a screening protocol in accordance with the 2016 Endocrine Society guidelines. ResultsA total of 1,005 patients undergoing sleep studies were reviewed; 354 patients had comorbid obstructive sleep apnea and hypertension. Patients were predominantly male (67%), with a mean age of 58 years (standard deviation = 12.9) and mean body mass index of 34 (standard deviation = 8.1). The screening rate for primary aldosteronism among included patients was 19% (n = 67). The screening rate was significantly higher after initiation of a dedicated primary aldosteronism screening protocol (23% vs 12% prior; P = .01). Fourteen screens (21%) were positive for primary aldosteronism, whereas 45 (67%) were negative and 8 (12%) were indeterminate. Four had prior abdominal cross-sectional imaging, with 3 revealing an adrenal adenoma. Compared with patients without primary aldosteronism, patients with positive primary aldosteronism screens were more likely to have a history of hypokalemia (36% vs 4.4%; P = .002). The frequency of hyperlipidemia, diabetes mellitus, and left ventricular hypertrophy did not differ between patients with positive versus negative screens. ConclusionCurrent screening practices for primary aldosteronism among patients with comorbid obstructive sleep apnea and hypertension are suboptimal. Patients evaluated at sleep centers may represent an optimal population for screening, as the prevalence of primary aldosteronism among this cohort appears high.