• obstructive sleep apnoea/hypopnoea syndrome

In 1997 Dr Wright and colleagues published a systematic review on the health effects of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) and the effectiveness of treatment with continuous positive airway pressure (CPAP).¹ They concluded that there was limited evidence of increased mortality or morbidity in patients with OSAHS, and that the evidence linking the condition to cardiac arrhythmias, ischaemic heart disease, left and right ventricular dysfunction, systemic and pulmonary hypertension, stroke, and automobile crashes was conflicting and inconclusive. They also concluded that, although CPAP had been shown to improve daytime sleepiness, there were insufficient data to determine its effect on quality of life, morbidity, or mortality. This review generated much controversy but was a wake up call² to investigators in this field that all were not convinced that OSAHS was an important condition that always warranted treatment. At that time our understanding of the natural history of OSAHS and the impact of treatment was at a similar stage to where we were with systemic hypertension and hypercholesterolaemia several decades ago. Considerable progress has been made in the past six years since the publication of this review, and many of the issues which it raised have started to be addressed. Long term population based prospective cohort studies have been initiated to examine the association of OSAHS with morbidity and mortality. Additional studies have been performed to determine the link between OSAHS and automobile crashes. A variety of large, well designed, randomised controlled trials have been completed or are in progress to determine …