Dimension of pain-related quality of life and self-reported mental health in men and women of the European Prospective Investigation into Cancer-Norfolk cohort: a population-based cross-sectional study

Both cognitive and behavioural factors are linked to the experience of pain as well as its interference with quality of life. Psychological distress has been shown to be associated to several emotional and social impairments. Although, the association between pain and mental health has been widely discussed, the understanding of life interference and outcome is not fully understood. This study examined the association of pain dimension and mental health domain in 16,051 participants of the EPIC-Norfolk cohort (mean age = 58.9 +/- 9.1 years). Study outcomes were depressive or anxious behaviour and limitations due to emotional problems and impairments in social functioning (mental functional health components of the Short Form-36 (SF-36)). Logistic regression models were constructed controlling for the potentially confounding factors including socio-economic variables (occupational social class, deprivation, marital status, education), lifestyle behaviour (physical activity, smoking, alcohol, dietary) and previous medical history. Strong interference in quality of life due to pain (bottom 20% of pain dimension score of SF-36) was significantly associated with poor MH in men and women (odds ratios (ORs) (95% confidence intervals (CIs)): 1.35 (1.19, 1.54) and 1.39 (1.25, 1.55), respectively; p < 0.0001) in fully adjusted models. Moreover, strong interference due to pain was also significantly associated with poor overall MH including emotional and social functioning (ORs (95% CIs): 1.42 (1.25, 1.62) and 1.39 (1.25, 1.55) respectively; p < 0.0001) in fully adjusted models; subsidiary analysis using linear regression models demonstrated similar results for these domains. Although a strong association has been shown, further research is needed to provide information on the different site and/or causes of pain which would allow stratification. Moreover, assuming a bi-directional nature of both domains, systematic assessment and management of pain have a lot of potential to improve the MH-related quality of life in the general population and vice versa.