Of the 6476 participants in the study, 1600 (25.93%) had experienced any type of chronic pain and any mental disorder in their lifetime. All types of pain were related to mental disorders, with the most substantial associations being mental disorders preceding onset of chronic pain.
These included affective disorders preceding headaches and any chronic pain; anxiety disorders preceding chronic back/neck pain, headaches, and any chronic pain; behavior disorders preceding headaches and any chronic pain; and any mental disorder preceding chronic back/neck pain, headaches, and any chronic pain.
“Our results corroborate and extend knowledge about the link between chronic pain and mental disorders in adults, which suggests that this relationship forms as early as childhood through adolescence, with an increasing level of comorbidity in adulthood,” wrote the researchers.
These findings give reason to hypothesize a causal role between mental disorders and the development of chronic pain, but more research is needed to determine whether this is the case. Current theories are that one condition is a risk factor for the other, or that underlying risk factors (such as the family environment) create vulnerabilities for both mental disorders and physical diseases. More research is needed to understand these mechanisms and to identify treatment strategies.