Pain is good for you? Non-cancer pain predicts improved 5-year survival

Shega J, Andrew M, Lau D, Herr K, Ersek MT, Weiner DK. Pain is good for you? Non-cancer pain predicts improved 5-year survival. Poster session presented at: American Geriatrics Society Annual Meeting; 2012 May 3; Seattle, WA.

Background: Non-cancer pain is known to result in significant morbidity, but little is known about its impact on mortality. We assessed the relationship of self-reported non-cancer pain at baseline and subsequent 5-year mortality among community-dwelling older adults. Methods: We analyzed data from a large prospective cohort study, the 1996 wave of the Canadian Study of Health and Aging. Non-cancer pain was assessed using the 5-point verbal descriptor scale, dichotomized into "no/very mild" versus "moderate" or greater pain. Frailty was measured as the sum of self-reported health (1 item), social support (1 item), co-morbidity (17 items), and functional abilities (14 items) with each item scored from 0 to 1, ranging from 0- 33, with higher scores indicating greater frailty. Cognitive status was measured using the Modified Mini-Mental Status Exam, ranging from 0-100, with a score < 77 indicating impairment. The Mental Health Inventory consists of 5 self-rated questions about one's psychological state and well-being, ranging from 0 to 30, with scores > 11 indicating depression. Multivariable logistic regression was used to analyze the relationship between pain and mortality, controlling for other factors. Results: Of the 5,703 participants, 4,694 (82.3%) had complete data for analysis. Of these, 35.4% reported moderate or greater pain and 28.6% had died at 5-year follow-up. The 5-year mortality odds increased by 1.12 (CI: 1.10, 1.13); p < 0.001 for each point increase in frailty. Those who were cognitively impaired (compared to intact) and depressed (compared to not) had an increased 5-year mortality odds of 2.35 (CI: 1.90, 2.90); p < 0.001 and 1.23 (CI: 1.03, 1.47); p < 0.001, respectively. Compared to those with mild or no pain, those with moderate or greater pain had a relative 5-year mortality odds of 0.78 (CI: 0.66,0.92); p < 0.001. Conclusions: Self-reported moderate or greater pain was associated with a lower odds of dying within 5 years. Reasons for this are unknown. Well designed prospective studies of non-cancer pain in older adults are needed to better understand its trajectory, associated factors, and outcomes.