The effects of depression and chronic pain on psychosocial and physical functioning.

OBJECTIVE: The present study employed causal modeling to examine the impact of somatic and cognitive symptoms of depression on the functioning of patients with chronic pain.

DESIGN: Path analyses were conducted to determine whether pain level is directly related to the psychosocial and physical dimensions of functional status or whether this relationship is mediated by depression.

SETTING: Subjects were recruited from a facial pain clinic at the University of Florida, an outpatient clinic associated with a tertiary-care health center.

PATIENTS: Subjects were 70 patients with chronic pain, 53 of whom had primary facial pain.

MAIN OUTCOME MEASURES: All subjects completed a packet of self-report questionnaires, including the Beck Depression Inventory, McGill Pain Questionnaire, and Sickness Impact Profile.

RESULTS: Results of path analyses indicated that both somatic and cognitive symptoms of depression significantly correlate with psychosocial functioning even after controlling for the effects of pain level, trait anxiety, and trait anger. Somatic symptoms of depression were significantly correlated with physical functioning after pain level, anxiety and anger were controlled.

CONCLUSIONS: This study indicates that depression is directly related to both the physical and the psychosocial functioning of facial pain patients, while self-reported level of pain is not. A better understanding of the impact of depression on chronic pain and the relationship of these two disorders could lead to improved assessment and treatment of chronic pain disorders.