Objective: To investigate the relationship between anxiety and depression and reporting of knee pain in the community.
Methods: Subjects (n = 374) were community volunteers aged 40 years and above who are participants in the Baltimore Longitudinal Study of Aging, a prospective multidisciplinary research study of normative aging. Knee pain was defined by the First National Health and Nutrition Examination Survey question "have you ever had pain in or around your knee on most days for at least one month?"; anxiety and depression were measured by the relevant subscales of the Arthritis Impact Measurement Scales questionnaire. All subjects had standing anteroposterior radiographs, read for Kellgren and Lawrence (K + L) grade.
Results: After adjustment for age, women reporting "ever" knee pain had significantly higher anxiety scores than those reporting "never" pain (3.06 +/- 0.26 versus 2.35 +/- 0.17; P = 0.025). Pain reporting was related neither to anxiety scores in men, nor to depression in either sex. Analysis stratified by radiographic severity, adjusted for age and gender, showed that differences in anxiety were confined to those reporting knee pain in the absence of radiographic change (i.e., K + L grade 0).
Conclusions: In the community, women reporting knee pain in the absence of radiographic osteoarthritis have higher anxiety scores than those without pain. Depression was not significantly related to knee pain in this population. Psychosocial factors may explain some of the discrepancy between reported knee pain and structural change as seen on x-ray.