Relationship between Pain and Dementia: The Mediating Effect of Depression among Chinese Elderly

Background: Chronic pain poses a significant problem for older adults and may potentially impact cognitive function. This study aimed to examine the cross-sectional relationship between pain severity and cognitive function in elderly individuals residing in the community. Additionally, this study sought to examine the mediating effect of depression on the relationship between pain and dementia. Methods: The study sample was derived from the 2018 China Health and Aging Longitudinal Study (CHARLS), comprising cross-sectional data from 4559 community residents aged 65 years or older. The primary outcome assessed was the occurrence of dementia, while the main independent variable was pain severity (none, little, somewhat, quite a bit, very). Depression score served as the mediating factor. Chi-square and binary logistic regression analyses were performed to examine the relationship between depression and the occurrence of pain and dementia. An intermediate model was constructed by stepwise regression. Results: The study indicates a significant association between cognitive impairment and both chronic pain and depressive symptoms in older adults living in China. Individuals who frequently report experiencing pain exhibit a higher likelihood of developing dementia when compared to those who do not report any pain (odds ratio (OR) = 1.72, p < 0.001). Moreover, depressive symptoms significantly mediate the relationship between pain and dementia, with the mediating effect accounting for 65.25%. Conclusions: Chronic pain not only directly impacts patients' cognitive function but also indirectly exacerbates cognitive impairment through depressive symptoms as a mediating variable. For elderly individuals experiencing depressive symptoms, it is important to provide appropriate psychological treatment in conjunction with pain management strategies.