Do Sleepy Rheumatoid Arthritis Patients Have a Sleep Disorder?

Objective: Subjective reports of sleep dysfunction are common in people with rheumatoid arthritis (RA). Our objective was to determine whether excess sleepiness in RA is associated with polysomnographic (PSG) abnormalities.

Methods: Twelve RA participants with abnormal sleep scores were identified in clinic and age/gender matched to RA participants with normal Epworth Sleepiness Scale (ESS) scores. A total of 25 participants were recruited. All participants underwent overnight PSG studies with measurement of apnoea-hypopnoea indexes (AHI). Questionnaire instruments, including the ESS, Berlin questionnaire for sleep apnoea risk, visual analogue scale for fatigue, modified Health Assessment Questionnaire (mHAQ) and the Center for Epidemiologic Studies - Depression (CES-D) score, along with RA assessments, were reapplied on the PSG study night.

Results: Seven men and 18 women participated. Ten participants had abnormal ESS scores and 15 had normal ESS scores on the PSG night. PSG data revealed that 68% of patients had abnormal AHI (≥ 5). Abnormal ESS (> 10) had an 80% positive predictive value (PPV) for abnormal AHI; the negative predictive value (NPV) of normal ESS was 40%. By contrast, high-risk categorization for obstructive sleep apnoea (OSA) by the Berlin questionnaire had a PPV of 77.8%, and for low-risk status, an NPV of 37.5%.

Conclusions: In the present study population, there was a high prevalence of abnormal AHI consistent with OSA. An abnormal ESS had high positive predictive value for an abnormal AHI.