Authors:
Thomas Benz (Bad Zurzach | CH)
Felix Angst (Bad Zurzach | CH)
Susanne Lehmann (Bad Zurzach | CH)
Stephan Wagner (Bad Zurzach | CH)
Beat Simmen (Zurich | CH)
Peter Sandor (Bad Zurzach | CH)
Michael Gengenbacher (Bad Zurzach | CH)
Jules Angst (Zurich | CH)
Background & Objectives. The cross-sectional relationship between pain and depression has stimulated research and generated a huge body of scientific literature over the years. The aim was to quantify and to compare the associations between longitudinal changes in pain and depression in different chronic pain conditions.
Material & Methods. Data were retrieved from 6 naturalistic, observational cohort studies. From baseline to the 6-month follow-up, the score changes on the Short Form (36) Health Survey (SF-36) bodily pain (pain) and the SF-36 mental health (depression) scales (0=worst, 100=best) were quantified, using partial correlations obtained by multivariate regression. Adjustment was performed by age, living alone/with partner, education level, number of comorbidities, baseline pain and baseline depression.
Results. Stronger associations were found between changes in levels of pain and depression for neck pain after whiplash (n=103, mean baseline pain=21.4, mean baseline depression=52.5, adjusted correlation r=0.515), knee osteoarthritis (n=177, 25.4, 64.2, r=0.502), low back pain (n=134, 19.0, 49.4, r=0.495), and fibromyalgia (n=125, 16.8, 43.2, r=0.467) than for lower limb lipedema (n=68, 40.2, 62.6, r=0.452) and shoulder arthroplasty (n=153, 35.0, 76.4, r=0.292). Those correlations were somewhat correlated to baseline pain (rank r=–0.429) and baseline depression (rank r=–0.314).
Conclusions. Moderate associations between changes in pain and depression levels were demonstrated across 5 of 6 different chronic pain conditions, in which relatively high pain levels persisted after conservative therapy. The associations between pain change and depression change tended to be stronger if pain and depression were worse at baseline. These two observed dose-response relationships are indicative of a certain degree of causal interference. Our results suggest that relieving pain may lead to the relief of depression and vice versa.