Objective: To determine what is known about neurobehavioral outcomes in patients with the obstructive sleep apnea hypopnea syndrome following treatment with continuous positive airway pressure (CPAP).
Data sources: Medline was searched. Abstracts presented at international meetings were searched and authors were contacted for additional trials. Bibliographies of the retrieved articles were reviewed.
Study selection: We reviewed all prospective studies that included: 1) a target population with obstructive sleep apnea, 2) CPAP as a study intervention, 3) evidence that the CPAP level was titrated until the AHI was < 5, and 4) standardized neurobehavioral outcomes appropriate for assessing sleep apnea.
Data synthesis: Twenty-six studies contributed to this qualitative systematic review. Effect sizes were calculated and adjusted for small samples and multiple measurements. Studies were then scored according to the outcome of the study.
Conclusions: This qualitative systematic review supports the assertion that CPAP has a significant and positive impact on subjective sleepiness and depression when randomized controlled trials are considered, and on fatigue, generic health-related quality of life, vigilance, and driving performance when all prospective trials are considered. These parameters appear to be sensitive to treatment duration and compliance. These results should be considered when developing health policy and designing future clinical trials.