A new means of assessing the quality of life of patients with obstructive sleep apnea: The MOSAS questionnaire

Background: The nightly use of continuous positive airway pressure (CPAP) increases the quality of life of patients affected by obstructive sleep apnea syndrome (OSAS). The aim of this study was to develop and validate a questionnaire to assess the psychological and physical impact of OSAS and adherence to the CPAP device. Methods: Ninety-six patients underwent a polygraphic examination to establish a diagnosis of OSAS. They attended educational sessions concerning CPAP and completed the Maugeri Obstructive Sleep Apnea Syndrome (MOSAS) questionnaire before the adaptation phase to the device and after six months, when the number of hours of CPAP use was documented. Results: Exploratory and confirmatory factor analysis of MOSAS section A revealed two factors with good internal consistency: "Sleep Apnea Psychological Impact" (alpha = 0.77) and "Sleep Apnea Physical Impact" (alpha = 0.75). Structural equation modeling confirmed the goodness of fit of the structure to the observed (RMSEA = 0.034; GFI = 0.95; AGFI = 0.92; and CFI = 0.96). MOSAS section B, which assesses the "discomfort and nuisance of CPAP," is mono-factorial with good internal consistency (alpha = 0.663). The Psychological Impact factor positively correlated with the anxiety (r = 0.44) and depression scores (r = 0.49) and the physical impact factor positively correlated with daytime sleepiness (r = 0.65). The discomfort and nuisance of CPAP negatively correlated with recorded CPAP use after six months (r = -0.52). Conclusions: The statistical quality of MOSAS is good, and it car be used to assess the psychological and physical impact of OSAS and subjective adherence to a CPAP device. (C) 2011 Elsevier B.V. All rights reserved.