Association Between Knee Pain, Impaired Function, and Development of Depressive Symptoms

To examine the association between knee pain and function and depressive symptoms in older Japanese adults.

Community-based prospective cohort study.

Kurabuchi Town, Gumma Prefecture, Japan.

Individuals aged 65 and older (N = 573; n = 260 men, n = 313 women) without depressive symptoms participated in baseline examinations in 2005 and 2006; 95.6% participated in follow-up interviews (2007-08).

Degree of knee pain and functional impairment was assessed at baseline using a self-administered questionnaire in Japanese based on an English version of the Western Ontario and McMaster Universities Osteoarthritis Index. The Geriatric Depression Scale was used to identify depressive symptoms in face-to-face home-visit interviews conducted 2 years later, and the association between knee pain and functional impairment and depressive symptoms was assessed using logistic regression.

During the 2-year follow-up, 11.9% of participants developed depressive symptoms, and pain and functional impairment were found to be associated with development of these symptoms. Pain at night while in bed (adjusted odds ratio (aOR) = 2.6, 95% confidence interval (CI) = 1.4-4.9) and difficulty putting on socks (aOR = 3.7, 95% CI: 1.8-7.5), getting into and out of a car (aOR = 3.4, 95% CI = 1.8-6.5), and taking off socks (aOR = 3.1, 95% CI = 1.5-6.5) were found to be most strongly associated with development of depressive symptoms.

Examining elderly people's responses to questions about pain at night and difficulties performing daily activities may be an efficient way of identifying those at high risk of developing depressive symptoms.