THE RELATIONSHIP BETWEEN FIBROMYALGIA AND INTERSTITIAL CYSTITIS

Interstitial cystitis (IC) is a relatively uncommon and enigmatic diso rder characterized by pain in the bladder and pelvic region, typically accompanied by urinary urgency and frequency. Fibromyalgia is a more common disorder, with the prominent symptoms being diffuse musculoskel etal pain and fatigue, and it has been well established that there is substantial clinical overlap between fibromyalgia and chronic fatigue syndrome (CFS). Although genitourinary and musculoskeletal symptoms pr edominate in IC and fibromyalgia respectively, both disorders share a number of features, including similar demographics, ''allied condition s'' (e.g. irritable bowel syndrome, headaches, etc.), natural history, aggravating factors, and efficacious therapy. We hypothesized that th ere was substantial clinical overlap between fibromyalgia and IC, and examined cohorts of individuals with these two disorders in parallel, to compare the spectrum of symptomatology. Sixty fibromyalgia patients , 30 IC patients, and 30 age-matched healthy controls were questioned regarding current symptomatology. A dolorimeter examination was also p erformed in the three groups to assess peripheral nociception. We foun d that the frequency of current symptoms was very similar for the fibr omyalgia and IC groups. Both the fibromyalgia and IC patients displaye d increased pain sensitivity when compared to healthy individuals, at both tender and control points. These data suggest that IC and fibromy algia have significant overlap in symptomatology, and that IC patients display diffusely increased peripheral nociception, as is seen in fib romyalgia. Although central mechanisms have been suspected to contribu te to the pathogenesis of fibromyalgia for some time, we speculate tha t these same types of mechanisms may be operative in IC, which has tra ditionally been felt to be a bladder disorder. (C) 1997 Elsevier Scien ce Ltd.