Stress modulates key psychological processes and characteristic symptoms in females with fibromyalgia.

OBJECTIVES To examine how stress interacts with psychological processes and key phenotypic symptom characteristics in females with fibromyalgia. METHODS Ninety-eight women with fibromyalgia, diagnosed according to ACR 1990 criteria, and 35 female healthy controls without pain were studied. Applied questionnaires included the following: Perceived Stress scale [PSS], Fibromyalgia Impact Questionnaire [FIQ], Perceived Control of Internal States (PCOIS), Mastery scale and the Profile of Mood States scale (POMS). RESULTS Perceived stress correlated significantly with the characteristic features of fibromyalgia including pain (p<0.05) and sleep change, fatigue and cognitive dysfunction (all p<0.001). Perceived stress correlated inversely with measures of control and positively with mood and neuroticism (all p<0.001). When controlling for stress, most of these variables were no longer significant, suggesting that stress impacts on the majority of variables associated with FM. CONCLUSIONS Stress in females with fibromyalgia associates with both key symptoms and a range of relevant psychological variables. Stress appears to have a major role in modulating several key 'up-stream' processes in fibromyalgia.