Becoming More Sensitive to Pain Increases Risk of Knee Pain Not Going Away.

Osteoarthritis affects 302 million adults worldwide, and can lead to chronic disability, frequently in the knee joint. A new study co-authored by School of Public Health researchers finds becoming more sensitive to pain, or pain sensitization, is an important risk factor for developing persistent knee pain in osteoarthritis.

The study was published in Arthritis and Rheumatology.

“Our findings suggest that therapy aimed at prevention or improvement of pain sensitization may be a novel approach to preventing persistent knee pain,” says study co-author Tuhina Neogi, professor of epidemiology. “Preventing pain is crucial to improving quality of life and function in patients who suffer from osteoarthritis.”

The researchers used data from a multicenter osteoarthritis study of 852 adults between the ages of 50 and 79 who had or were at risk of knee osteoarthritis—but were free of persistent knee pain at the beginning of the study. The study collected pain sensitization measurements, sociodemographic data, and data on risk factors traditionally associated with knee pain such as psychological factors, widespread pain, and poor sleep. The participants were then followed over two years to see who developed persistent knee pain.

For the new study, the researchers used the data on risk factors and pain sensitization to identify subgroups of participants who were at more or less risk of developing persistent knee pain. They found that the participants with the highest degree of sensitization had the highest risk of developing persistent knee pain, and that being female, a person of color, and over the age of 65 were significant predictors of being a member of subgroup with the highest degree of sensitization.

“Understanding the factors that contribute to the development of persistent pain is critical in improving our ability to prevent its onset and the transition to more persistent pain,” says lead author Lisa Carlesso of the University of Montreal.

The study was co-authored by by Yuqing Zhang of the School of Medicine and by alumnus Na Lu (SPH’14). The other co-authors were: Neil A. Segal of the University of Kansas; Laura Frey‐Law of the University of Iowa; Michael Nevitt of the University of California, San Francisco; and Cora E. Lewis of the University of Alabama.