Claudia Campbell, PhD, the study's lead author. (Photo credit: Claudia Campbell, PhD)

Claudia Campbell, PhD, the study’s lead author. (Photo credit: Claudia Campbell, PhD)

Knee osteoarthritis patients who sleep poorly and are consumed by thoughts of pain may experience an amplification of their clinical pain, according to a study published recently in Arthritis Care & Research, a journal of the American College of Rheumatology (ACR).

In their case-controlled study, researchers categorized 208 participants into four groups, according to a news release from Wiley: OA patients with insomnia, OA patients with normal sleep habits, healthy controls with insomnia, and healthy controls without a pain syndrome and normal sleep. From the total number of participants, 72% were female. Everyone in the study completed sleep assessments, psychological and pain evaluations, and sensory testing.

The release explains that after studying the results, the research team found that the subjects with knee OA and insomnia had the greatest degree of central sensitization—or amplification of pain—compared to the controls. They also found that patients with poor sleep and high catastrophizing scores—or a high degree of thoughts of pain—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,” says the study’s lead author, Claudia Campbell, PhD, an associate professor in the Department of Psychiatry and Behavioral Sciences at Johns Hopkins University School of Medicine in Baltimore, in the release.

“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,” she explains.

[Source(s): Wiley, EurekAlert]