Fibromyalgia and cognition.

Patients with fibromyalgia frequently complain of cognitive problems or "fibrofog." The existence of these symptoms has been confirmed by studies of the incidence of cognitive problems in fibromyalgia patients and by the results of objective tests of metamemory, working memory, semantic memory, everyday attention, task switching, and selective attention. The results of these tests show that fibromyalgia patients have impairments in working, episodic, and semantic memory that mimic about 20 years of aging. These patients have particular difficulty with memory when tasks are complex and their attention is divided. Cognitive symptoms in these patients may be exacerbated by the presence of depression, anxiety, sleep problems, endocrine disturbances, and pain, but the relationship of these factors to cognitive problems in fibromyalgia patients is unclear. Standardized tests and treatment have not yet been established for cognitive problems in fibromyalgia patients.