History of affective disorder and the experience of fatigue in rheumatoid arthritis.

OBJECTIVE: To evaluate how a prior affective disorder (major depression or generalized anxiety disorder) affects current fatigue among individuals with rheumatoid arthritis (RA). To determine whether that relationship is mediated by self-efficacy expectations.
METHODS: Forty-eight RA patients with a prior affective disorder and 74 without a history of affective disorder completed a mailed questionnaire that included the Multidimensional Assessment of Fatigue and indicators of neuroticism and self efficacy.
RESULTS: RA patients with a history of affective disorder reported higher levels of fatigue than those with no previous affective disturbance. Controlling for neuroticism and self efficacy, affective disorder history continued to predict current fatigue. Mediational analyses revealed both direct and indirect effects (via self efficacy) of history of affective disorder on the experience of fatigue in RA.
CONCLUSION: History of affective disorder independently predicts higher levels of fatigue in RA patients, and self efficacy plays a mediating role in this relationship.