Objective: fatigue and sleep problems are significant in patients with ankylosing spondylitis (AS). This subanalysis of the RHAPSODY study (Review of Safety and Effectiveness with Adalimumab in Patients with Active Ankylosing Spondylitis) was conducted to evaluate the effect of adalimumab on sleep in patients with active AS.
Methods: all patients (n = 1250) had active AS and received adalimumab 40 mg every other week during the 12-week open-label treatment period. Sleep was assessed by the Medical Outcomes Study Sleep Scale (MOS-SS) at screening and Weeks 6, 12, and 20 (optional continuation period). Effect sizes were calculated to determine clinical significance. Paired Student t tests compared the change in the MOS-SS domains from Week 12 to baseline. Correlation coefficients were calculated to determine the relationship between change in sleep domains and other Week 12 clinical and patient-reported outcomes (Bath AS Disease Activity Index, C-reactive protein, nocturnal pain, total back pain, Bath AS Functional Index, patient's global assessment of disease activity, morning stiffness, Short Form-36 Health Survey, and Work Productivity and Activity Impairment questionnaire components).
Results: at week 12, adalimumab significantly improved sleep in each of the MOS-SS domains (p < 0.001). Effect sizes for 3 of the 6 domains (disturbance, -0.69; adequacy, 0.55; somnolence, -0.52) and both sleep problems indices (Index I, -0.68; Index II, -0.77) were moderate, suggesting clinical significance. Change in the MOS-SS Sleep Problem Index II was moderately correlated with change in most clinical and patient-reported outcomes. Sleep improvements were similar in patients with and without radiographically advanced AS.
Conclusion: adalimumab improves overall sleep and sleep quality in patients with active AS.