Prognosis and cardiovascular morbidity and mortality in prospective study of hypertensive patients with obstructive sleep apnea syndrome in St Petersburg, Russia
Lyudmila S. Korostovtseva, Yurii V. Sviryaev, Nadezhda E. Zvartau, Alexandra O. Konradi, Alexander L. Kalinkin
Med Sci Monit 2011; 17(3): CR146-153
Background: To assess the impact of obstructive sleep apnea-hypopnea syndrome (OSAHS) on prognosis and cardiovascular morbidity and mortality in relation to other major cardiovascular risk factors.
Material/Methods: This prospective study recruited 234 patients from an out-patient clinic. Based on the Berlin questionnaire, 147 patients (90 males, mean age 52.1±10.4 years) with highly suspected sleep breathing disorders were included in the study. Based on cardiorespiratory monitoring, patients were divided into 2 groups: 42 patients without sleep breathing disorders (SBD), and 105 patients with OSAHS. Among these, 12 patients started CPAP therapy and formed the third group.
Results: The mean follow-up period was 46.4±14.3 months. Event-free survival was lowest in the untreated OSAHS patients (log rank test 6.732, p=0.035). In the non-adjusted regression model, OSAHS was also associated with a higher risk of cardiovascular events (OR=8.557, 95% CI 1.142–64.131, p=0.037). OSAHS patients demonstrated higher rates of hospitalization compared to the control group without SBD (OR 2.750, 95%CI 1.100–6.873, p=0.04).
Conclusions: OSAHS hypertensive patients, and in particular, according to our model, patients with severe OSAHS (AHI ≥30/h), are at higher risk of fatal and non-fatal cardiovascular events. Moreover, untreated OSAHS patients demonstrate higher rates of hospitalization caused by the onset or deterioration of cardiovascular disease.
Keywords: Russia - epidemiology, Prospective Studies, Prognosis, Morbidity, Middle Aged, Male, Hypertension - mortality, Humans, Follow-Up Studies, Female, Antihypertensive Agents - therapeutic use, Aged, 80 and over, Aged, Adult, Sleep Apnea, Obstructive - mortality, Survival Analysis, Syndrome