[Clinical and cardiovascular characteristics of patients with obstructive sleep apnoeas without excessive daytime sleepiness]

Abstract

Objectives: To investigate whether patients with obstructive sleep apnoea (OSA) without excessive daytime sleepiness (EDS) have cardiovascular problems and different clinical characteristics from OSA with EDS.

Methods: Two groups of patients were compared retrospectively, one without EDS (Epworth <11) and another control group with EDS (Epworth>10), adjusted for sex, age, body mass index (BMI) and apnoea-hypopnoea index (AHI). The diurnal and nocturnal symptoms of OSA were analysed along with, polysomnography variables, prevalence of hypertension, diabetes mellitus, hyperlipaemia and history of previous cardiovascular events. A logistic regression was performed adjusted for multiple confounding factors to identify the variables associated with OSA without EDS.

Results: A total of 166 patients without EDS were studied (Epworth 7.2±2.4) and 295 with EDS (Epworth 14.5±2.5). In the adjusted multivariate logistic regression, OSA without EDS is independently associated with a feeling of restful sleep (95% CI: 1.70 to 3.93), less intellectual deterioration (95% CI: 0.30 to 0.95) and less effective sleep (95% CI: 0.96 to 0.99). No differences were found as regards prevalence of cardiovascular comorbidity, previous cardiovascular events, sleep structure or nocturnal clinical symptoms of OSA. When the patients who were in the extreme quartiles of the Epworth scale were analysed, the results obtained were equivalent to those of the whole series, with only intellectual deterioration disappearing from the final model.

Conclusions: After adjusting for confounding variables, OSA without EDS has a similar prevalence of cardiovascular comorbidities and less diurnal symptoms than OSA with EDS.