Biological and psychological factors associated with memory function in fibromyalgia syndrome.

Fibromyalgia is a stress-related disorder characterized by chronic pain, memory impairment, and neuroendocrine aberrations. With the hypothesis that biological and psychological symptoms may underlie the cognitive problems, the relative influences of neuroendocrine function and psychological factors on declarative memory were examined among 50 women with fibromyalgia. This within-group analysis controlled for age, education, pain, and relevant medications. Neuroendocrine function and depression had significant independent associations with memory function. Higher log-transformed mean salivary cortisol levels were associated with better performance on both immediate and delayed visual recall and with delayed verbal recall. Depressive symptoms were negatively associated with verbal recall. These findings suggest that a basic disorder of endocrine stress responses may contribute to the cognitive symptoms experienced by fibromyalgia patients.