Obstructive sleep apnoea as a risk factor for hypertension.

It is controversial whether obstructive sleep apnoea (OSA) is a risk factor for hypertension as previous reviews of the subject have emphasized the confounding effect of obesity. We examined evidence from recent studies to reassess this debate. Cross-sectional studies from sleep clinic population (Sydney Sleep Cohort, Gothenburg Sleep Clinic Cohort), community sample (Busselton Sleep Survey, Wisconsin Sleep Cohort) and obese population (Swedish Obese Subjects Study) provide stronger evidence that the relationship between sleep apnoea and hypertension is an independent one. Moreover recent studies looking at the effect of sleep apnoea treatment have demonstrated a fall in blood pressure independent of weight change. More definitive studies are required but recent data provide increasing evidence that OSA is an independent risk factor for hypertension.