Sleep Apnea in Postmenopausal Women is Associated with Joint Pain Severity and Fatigability: a Cross-Sectional Study.

Objective: This study aimed to investigate the relationships between sleep apnea parameters and various symptoms in postmenopausal women who had treatment-resistant sleep disorders. Methods: The respiratory disturbance index (RDI), the number of times apnea-hypopnea occurred in an hour, and transcutaneous oxygen saturation (SpO(2)) were monitored during one night of sleep using a portable monitoring device in 51 postmenopausal women who did not have an improved subjective sleep quality with the use of hypnotics. Physical and psychological health statuses and subjective sleep disturbance were evaluated using validated questionnaires, including the Epworth Sleepiness Scale, the Cornell Medical Index, and the Questionnaire for Assessment of Climacteric Syndrome in Japanese Women. The associations between RDI, nadir SpO(2) and various symptoms, as well as cardiovascular parameters, such as blood pressure, serum lipid profile, and glucose tolerance, were analyzed separately. Results: Among the 51 study participants, seven (13.7%) were diagnosed with obstructive sleep apnea. After adjustment for age, body mass index, and the background factors related to RDI and nadir SpO2, the association remained significant between a higher RDI and joint pain (Questionnaire for Assessment of Climacteric Syndrome in Japanese Women) (standardized partial regression coefficient [beta] = 0.423, P = 0.016), and between lower nadir SpO(2) and fatigability (Cornell Medical Index) (beta = -0.472, P = 0.007). Conclusions: Detailed examination of sleep-disordered breathing is warranted in women with severe joint pain and fatigability.