title: Prognosis and cardiovascular morbidity and mortality in prospective study of hypertensive patients with obstructive sleep apnea syndrome in St Petersburg, Russia.
abstract: 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.
  
  
  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.
authors.affiliation: Almazov Federal Heart, Blood and Endocrinology Centre, Saint-Petersburg, Russia.
authors.forename: Lyudmila S
authors.initials: LS
authors.lastname: Korostovtseva
authors.forename: Yurii V
authors.initials: YV
authors.lastname: Sviryaev
authors.forename: Nadezhda E
authors.initials: NE
authors.lastname: Zvartau
authors.forename: Alexandra O
authors.initials: AO
authors.lastname: Konradi
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Kalinkin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000188:drug therapy / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011379:Prognosis; D011446:Prospective Studies; D012426:Russia / Q000453:epidemiology; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000401:mortality*; D016019:Survival Analysis; D013577:Syndrome
chemical_list: D000959:Antihypertensive Agents