Untreated severe obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular mortality in the elderly, and adequate treatment with continuous positive airway pressure (CPAP) may significantly reduce this risk, according to a new study from researchers in Spain.
"Although the link between OSA and cardiovascular mortality is well established in younger patients, evidence on this relationship in the elderly has been conflicting," said lead author Miguel ángel Martínez-García, MD, of La Fe University and Polytechnic Hospital in Valencia, Spain. "In our study of 939 elderly patients, severe OSA not treated with CPAP was associated with an increased risk of cardiovascular mortality especially from stroke and heart failure, and CPAP treatment reduced this excess of cardiovascular mortality to levels similar to those seen in patients without OSA."
The findings were published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.
All subjects in this prospective, observational study were 65 years of age or older. Median follow-up was 69 months. Sleep studies were conducted with either full standard polysomnography or respiratory polygraphy following Spanish guidelines. OSA was defined as mild-to-moderate (apnea-hypopnea index [AHI] 15-29) or severe (AHI ≥30). Patients with AHI <15 acted as controls. CPAP use ≥4 hours daily was considered as good adherence to treatment.