CPAP treatment of a population-based sample - what are the benefits and the treatment compliance?

Background & purpose: Continuous positive airway pressure (CPAP) treatment has positive effects, including improved insulin sensitivity in sleep-laboratory cohorts with obstructive sleep apnea syndrome. There is still a lack of data on benefits obtained and possibilities to treat less symptomatic individuals. The aim of this study was to evaluate the effect of CPAP treatment on metabolic profile and quality of life (QoL) in a population-based sample of men with sleep apnea. Another purpose was to investigate the compliance to CPAP in this population. Patients and methods: A population-based sample of 38 men with an AHI >= 10 were treated with CPAP regardless of symptom profile. The controls included men with AIR < 10 matched for age and hypertension. The effects were evaluated after 3 weeks and 6 months. Insulin resistance was quantified using the homeostasis model assessment (HOMA). Daytime sleepiness, QoL and subjective symptom load was assessed using the Epworth Sleepiness Scale (ESS), the Medical Outcomes Study Short Form Health Survey (SF-36) and the Minor Symptoms Evaluation-Profile (MSE-P) questionnaires, respectively. Results: Complete three-week data were obtained from 28 treated men and 28 controls. Compared with controls, the CPAP group displayed a greater reduction of fasting serum insulin (P=0.02), decrease in insulin resistance (P=0.01) and an increase in IGF-1 (P=0.005). The CPAP group further showed an improvement in the SF-36 domains of mental health (P=0.03) and vitality (P=0.06) and a reduction in symptom load in the sleep dimension of the MSE-P. Only 11 (29%) of subjects starting CPAP were still on treatment after 6 months. Those who still used CPAP had a higher score on ESS at baseline (11.3 (4.4) vs. 5.9 (3.4), P<0.0001). Conclusions: Benefits of short-term treatment included signs of reduced insulin resistance and improved QoL. However, in this population-based sample compliance with CPAP was very low. More severe sleepiness was a positive predictive factor for treatment compliance. (C) 2006 Elsevier B.V. All rights reserved.