HealthDay News — Untreated obstructive sleep apnea (OSA) is associated with increased cardiovascular mortality in women, but continuous positive airway pressure (CPAP) treatment reduces the risk of mortality, study data published in the Annals of Internal Medicine indicate.
Francisco Campos-Rodriguez, MD, from Valme University Hospital in Seville, Spain, and colleagues observed 1,116 women, consecutively referred to two sleep clinics for suspected OSA from 1998 to 2007. The controls had an apnea-hypopnea index (AHI) of <10. OSA was defined as an AHI of ≥10. Women with and AHI of 10 to 29 were classified as mild to moderate cases, whereas those with an AHI of ≥30 were classified as severe.
Treatment was defined as adherence to CPAP treatment for four hours or more per day. The researchers conducted followed-up until December 2009 to determine incidence of the primary end point of cardiovascular death.
The control group had a significantly lower cardiovascular mortality rate (0.28 per 100 person-years) than the untreated groups with mild to moderate OSA (0.94 per 100 person-years) or severe OSA (3.71 per 100 person-years). Fully adjusted hazard ratios (HRs) for cardiovascular mortality were 3.50 and 0.55 for the untreated and treated severe OSA groups, respectively, and 1.60 and 0.19 for the untreated and treated mild-to-moderate OSA groups, respectively.
“Severe OSA is associated with cardiovascular death in women, and adequate CPAP treatment may reduce this risk,” the researchers wrote.