METHODS AND RESULTS: One hundred and nine consecutive patients with resistant
hypertension were prospectively evaluated with plasma
renin activity (PRA), PAC, 24-hour urinary
aldosterone excretion (UAldo), and polysomnography.
Hyperaldosteronism (PRA < 1 ng x mL(-1) x h(-1) and UAldo > or = 12 microg/24-h) prevalence was 28% and OSA prevalence was 77%. In patients with
hyperaldosteronism, OSA prevalence was 84%, compared with 74% in hypertensive patients with normal
aldosterone levels. There were no significant differences in body mass index or neck circumference between
aldosterone groups. PAC and UAldo were both significantly correlated with
apnea-hypopnea index (AHI) in the high-
aldosterone group (p = 0.568, p = 0.0009; p = 0.533, p = 0.002, respectively). UAldo correlated weakly with
apnea-hypopnea index in the normal-
aldosterone group, but there was no significant correlation between PAC and AHI in the normal-
aldosterone group (p = 0.224, p = 0.049; p = 0.015, p = 0.898, respectively).
CONCLUSIONS: Our analysis of patients with resistant
hypertension confirms a markedly high prevalence of OSA in this group. Furthermore, severity of OSA was greater in those patients with
hyperaldosteronism and related to the degree of
aldosterone excess. The correlation between OSA severity and
aldosterone supports the hypothesis that
aldosterone excess contributes to greater severity of OSA.