The potential importance of the obstructive sleep apnoea syndrome (OSA) has been recognised only in the last few years. Epidemiological studies suggest that symptomatic OSA occurs in 1-2% of middle-aged men and in approximately half that number of women. The relation of OSA to vascular disease is uncertain and the main indication for treatment is the relief of disabling sleepiness. Two recent evidence based analyses have produced diametrically opposed conclusions on the efficacy of treatment ...