(HealthDay News) — For patients with knee osteoarthritis (OA) and insomnia, cognitive-behavioral therapy for insomnia (CBT-I) is efficacious and deceases clinical pain, according to a study published in the May issue of Arthritis & Rheumatology.
Michael T. Smith, PhD, from the Johns Hopkins University School of Medicine in Baltimore, and colleagues conducted a randomized trial of CBT-I in 100 patients with knee OA and insomnia (mean age, 59.4 ± 9.5 years). Patients were randomly allocated in a 1:1 ratio to receive eight sessions of CBT-I or behavioral desensitization (placebo).
The researchers observed substantial improvement in sleep in both groups of patients in intent-to-treat analyses. Significantly greater reductions in wake after sleep onset (WASO) were seen for patients in the CBT-I group, as measured by patient diary and polysomnography. In both groups, patients reported significant and comparable reductions in pain over six months; one-third reported a pain severity reduction of 30%. Decreases in clinical pain were predicted by baseline-to-post-treatment reductions in WASO, as measured by diary and polysomnography. Compared with behavioral desensitization, the effect was significantly greater for CBT-I. Laboratory measures of pain modulation did not change significantly.
“These findings strongly support the efficacy of CBT-I for treating insomnia in patients with OA and highlight the notion that future work is needed to identify the mechanisms by which improvements in sleep reduce clinical pain,” the authors write.