Incident Hypertension in Patients with Obstructive Sleep Apnea

Cross-sectional studies show a relation between obstructive sleep apnea (OSA) and hypertension, but prospective studies of incident hypertension have yielded conflicting results. OSA patients who receive continuous positive airway pressure (CPAP) experience short-term reductions in blood pressure, but CPAP's long-term effects are unknown, as are its cardiovascular (CV) benefits for patients with mild OSA. In two related studies from Spain, investigators explored these issues.

In one study (median follow-up, 12 years), researchers recruited 1889 patients (mean age, 50; mean body-mass index [BMI], 30 kg/m²) without hypertension who were referred for polysomnography. Of 1579 with OSA, 1117 (71%) were eligible for CPAP. In analyses adjusted for CV risk factors, BMI, and other variables, risk for incident hypertension in OSA patients who adhered to CPAP therapy was 29% lower than in non-OSA participants. In contrast, risk for incident hypertension was higher in OSA patients who were ineligible for CPAP (+33%), in those who declined CPAP (+96%), and in those who did not adhere to CPAP therapy (+78%) than in non-OSA participants.

In another study from the same investigators (median follow-up, 4 years), 725 patients (mean age, 52; mean BMI, 31 kg/m²) with OSA but without daytime sleepiness were randomized to CPAP or no therapy. No difference was found between the CPAP and control groups in incident hypertension or adverse CV events.