Among patients with osteoarthritis of the knee, women experienced greater sensitivity to various pain modalities, such as lower tolerance to heat, cold, and pressure, and greater widespread pain than men, according to a study published online ahead of print October 5 in Arthritis Care & Research.
“Many questions still remain as to why women with knee osteoarthritis are more sensitive to painful stimuli than are men. While therapeutic approaches to control pain are only beginning to take these sex differences into account, there is still quite a bit of research yet to be done to help reduce this gender gap and improve clinical therapies for men and women alike,” said lead author Emily J. Bartley, PhD, a Research Assistant Professor at the University of Florida College of Dentistry in Gainsville.
Emily J. Bartley, PhD
For this study, 288 participants between the ages of 45 and 85 completed a battery of quantitative sensory pain procedures assessing sensitivity to contact heat, cold pressor, mechanical pressure, and punctate stimuli. Differences in temporal summation were examined, along with measures of clinical pain and functional performance.
When compared to men, women exhibited greater sensitivity to multiple pain modalities (eg, lower heat, cold, pressure thresholds/tolerances, greater temporal summation of pain). There were no sex differences in clinical pain with the exception of greater widespread pain observed in women. Although there were select age-related differences in pain sensitivity, sex differences in pain varied minimally across age cohort.
“Overall, these findings provide evidence for greater overall sensitivity to experimental pain in women with symptomatic knee osteoarthritis compared with men, suggesting that enhanced central sensitivity may be an important contributor to pain in this group,” wrote Dr. Bartley and colleagues.