Defense mechanisms in patients with fibromyalgia and major depressive disorder

Background and objectives: Fibromyalgia (FM) and depression has been suggested to share a common underlying etiology. Few studies have investigated the role of emotional regulation processes in FM compared to depressive disorders. The purpose of the current study was to explore the use of defense mechanisms in FM patients with and without comorbid lifetime depressive disorder (LDD), and to compare their use of defenses to healthy control subjects and patients with Major Depressive Disorder (MDD). Methods: A total of 91 participants were included (17 with FM and LDD, 25 with FM but not LDD, 24 with MDD, and 25 healthy controls). Depressive disorders were identified by using the Structured Clinical Interview for DSM Axis I disorders (SCID-I). All diagnosis of FM were confirmed to meet the American College of Rheumatology’s criteria for FM. The Life Style Index (LSI) was used to measure defense mechanisms. Results and Conclusions: Group comparisons indicated that MDD patients and FM patients with LDD made significantly more use of defenses than healthy controls, whereas FM patients without LDD made significantly less use of defenses than both MDD patients and FM patients with LDD, but did not differ from healthy controls. Follow up analyses indicated significant main effects for the defense mechanisms of regression, compensation and displacement. This study suggests that FM and depression do not share common risk factors in terms of restricted affects or avoidance of conflicted feelings. Received 1 October 2007 Revised 26 June 2008 Accepted 11 July 2008 186 TORMOD LANDMARK ET AL.