Abstract

Objective: Fibromyalgia patients often complain of unrefreshed sleep. Polysomnography findings have shown a decrease in slow wave sleep, alpha-delta EEG pattern, decreased rapid eye movement (REM) sleep and increased number of arousals. However, the sleep abnormality and unrefreshed sleep in fibromyalgia could be more than a reduction in slow wave sleep and alpha-intrusion pattern. Emerging information has shown the comorbidity of fibromyalgia with obstructive sleep apnea. The aim of this study is to evaluate the frequency of obstructive sleep apnea (OSA) in fibromyalgia patients and its occurrence with REM and non-REM (NREM) sleep.

Methods: A retrospective chart review was conducted at our center. Charts of patients who visited the clinic of one psychosomatic medicine specialist from January 2015 to December 2015 were reviewed for patients diagnosed with fibromyalgia, OSA, and patients with combined fibromyalgia and OSA. A sleep study (polysomnography test results) of patients carrying a combined diagnosis of OSA and fibromyalgia were also reviewed.

Results: Of the total number of patients (n=117) patients diagnosed with fibromyalgia was n=14 (12%). Out of these 14 patients, 10 patients also had obstructive sleep apnea (71%). And of these patients’ polysomnography results were available n=8, decreased REM sleep n=5 (62%), apnea/hypopnea worse in REM sleep n=6 (75%), with a mean REM Apnea Hypopnea Index of 37.5 events per hour.

Conclusion: There is a possible association of fibromyalgia with OSA where REM sleep abnormalities were found in patients with combined fibromyalgia and OSA.

Keywords: Fibromyalgia; Obstructive sleep apnea; Non-REM sleep; REM sleep; Alpha intrusion pattern; Alpha-delta pattern; Slow wave sleep; Hyperalgesia