People with fibromyalgia are very commonly diagnosed with obstructive sleep apnea, highlighting the importance of sleep studies for better management of the condition, researchers from Loyola University Chicago report.
The review study, “Obstructive sleep apnea co-morbidity in patients with fibromyalgia: a single-center retrospective analysis and literature review,” was published in the journal Rheumatology: Research and Reviews.
Improving sleep patterns and sleep quality is vital in the symptomatic management of fibromyalgia. Sleep disturbance, and specifically obstructive sleep apnea (OSA), is prevalent in fibromyalgia patients, but often undiagnosed. This causes a delay in treatment, as well as “leading to medical and economic consequences,” the researchers said.
Determining the rate of co-morbidity — or the co-occurrence — of fibromyalgia and OSA will help to improve the treatment and management of fibromyalgia, according to the study.
The team searched the Loyola University Chicago health system medical records and identified patients, 18 years and older, diagnosed with fibromyalgia and OSA from 2012 to 2016. They then determined the overlap between the two diagnoses.
The researchers assessed clinical data from all outpatient clinics in the system, including psychiatry, sleep, and rheumatology.
Among the total number of patients in each clinic, the greatest number of fibromyalgia patients — 2,505 of 8,607, or 29.1% — were identified in the rheumatology clinic. Next was the sleep clinic (1,205/6,975; 17.2%), followed by psychiatry (364/2,393; 15.2%), and other clinics (15,106/380,666; 3.9%).
The majority (14,833) of all those diagnosed with fibromyalgia (19,180) were women.
Further review showed that, among those with fibromyalgia, OSA was diagnosed in 85.8% (1035/1205 ) of patients in sleep clinics, 42% (153/364) in psychiatry, 18.7% (470/2,505) in rheumatology, and 3.6% (552/15,106) in the other clinics.
“The varying prevalence of [fibromyalgia] patients with co-morbid OSA in sleep clinics, when compared to other outpatient clinics, suggests a discrepancy in the identification of [fibromyalgia] patients with OSA,” the researchers said.
The review found that, except in the sleep clinic, people with fibromyalgia were not regularly referred to polysomnography (sleep study) to screen for OSA or other sleep disorders. All fibromyalgia patients in the sleep clinic had the sleep study done at least once.
However, no sleep study was performed in 93.5 % of fibromyalgia patients in the rheumatology clinic, or in 96% of those in all other clinics. “We were not able to identify, in our retrospective study, the reason for this low referral rate. A prospective survey could address this,” the researchers said.
“Our analysis suggests that there could be a correlation between FM and OSA, and referral to sleep studies is recommended in the management of patients with FM,” they concluded.