Multiple Pain Complaints in Patients With Major Depressive Disorder

Abstract
Objective: To characterize the co-existence of multiple pain-related complaints in patients enrolled in a series of pharmaceutical company drug trials for the treatment of Major Depressive Disorder (MDD). Method: Pooled ‘blinded' data from 2191 patients enrolled in randomized, multicenter, double-blind placebo-controlled studies for the treatment of MDD were analyzed. Painful symptoms were assessed using the seven pain symptoms subset of the Somatic Symptoms Inventory: ‘Headache,' ‘Pain in lower back,' ‘Neck pain,' ‘Pain in joints,' ‘Soreness in muscles,' ‘Pain in heart or chest,' and ‘Pain or cramps in abdomen.' The 17-item Hamilton Depression Rating Scale (HAMD) was used to assess severity of depression. Results: Of those meeting the study entry criteria (total HAMD score ≥15), 25% reported no pain complaints and 18% reported 1 pain compliant; the majority (57%) of patients reported the co-existence of multiple pain-related complaints, with 14%, 12%, 11%, 11%, 7%, and 3% of patients reporting 2, 3, 4, 5, 6 and 7 different pain symptoms, respectively. The number of pain-related symptoms experienced was moderately related to severity of depression (r = 0.35), with the most common pain symptom combinations being among headaches, lower back pain, neck pain, pain in joints, and soreness in muscles. Conclusions: This study supports pain as a component feature of MDD. The number of comorbid pain-related complaints, which generally increased as a function of depressive severity, should be considered in the diagnosis of depression, planning of treatment strategies, and measurement of treatment outcome. MDD = Major Depressive Disorder; SSI = Somatic Symptoms Inventory; HAMD = Hamilton Depression Rating Scale; DSM-IV-TR = Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision; ICD-10 = International Classification of Diseases, 10th Revision.