Patients with knee osteoarthritis (OA) who have poor sleep habits display greater central sensitization of pain, according to a study published online ahead of print June 4 in Arthritis Care & Research. Study findings also showed that OA patients who catastrophize had increased central sensitization that was associated with greater pain.
“Our study is the largest and most comprehensive examination of the relationship between sleep disturbance, catastrophizing, and central sensitization in knee OA,” stated lead author Claudia Campbell, PhD, an Associate Professor of Psychiatry and Behavioral Sciences at Johns Hopkins University School of Medicine in Baltimore.
The case-controlled study included 208 participants who were categorized according to 4 groups: patients who have OA and insomnia, patients who have OA and normal sleep habits, healthy controls with insomnia, and healthy controls without a pain syndrome and normal sleep. In all, 72% of the study’s participants were female.
Participants completed multimodal sleep assessments (eg, questionnaire, diary, actigraphy, and polysmnography) and extensive evaluation of pain using clinical measures and quantitative sensory testing to evaluate associations between central sensitization, catastrophizing, and insomnia.
Results showed that the participants with knee OA and insomnia had the greatest amount of central sensitization compared with controls. The team found patients with poor sleep and high catastrophizing scores reported increased levels of central sensitization. In turn, central sensitization was significantly associated with increased clinical pain.
“While no causal processes may be determined from this study, our data suggest that those with low sleep efficiency and higher catastrophizing have the greatest central sensitization. Understanding the intricate relationship between sleep, central sensitization, and catastrophizing has important clinical implications for treating those with chronic pain conditions such as knee OA,” Dr. Campbell stated.