Chronic pain and depression

Chronic pain and depression are epidemiologically linked. Functional neuroimaging techniques demonstrate differences in brain activity among adults with chronic pain and depression. Knowledge of the epidemiologic associations and pathophysiological processes that interrelate chronic pain and depression provide a broad framework for understanding the clinical use of antidepressants in the treatment of chronic pain. Epidemiologic studies have demonstrated an indirect association between depressive symptoms and chronic pain. Depressive symptoms were measured using the Center for Epidemiological Studies-Depression scale and the severity of neck and back pain was measured using the Chronic Pain Questionnaire. Consistent with epidemiologic studies which have identified a direct association between chronic pain and depression, experimental studies have demonstrated that patients with depression have altered pain thresholds and tolerances. Tricyclic antidepressants are predominantly used in the treatment of neuropathic pain, but the drugs have shown efficacy in the treatment of chronic low back pain and fibromyalgia.