Overactive Bladder Symptoms in Patients with Fibromyalgia: A Systematic Case-Controlled Study

Background: A recent survey reported an association between fibromyalgia and overactive bladder. Objective: To carry out the first systematic case-controlled study to compare the level of overactive bladder symptoms in a group of fibromyalgia patients and a group of matched controls. Methods: The symptom-bother OAB-q8 questionnaire and Revised Fibromyalgia Impact Questionnaire (FIQR) were administered to 27 patients who fulfilled the revised diagnostic criteria for fibromyalgia of the American College of Rheumatology and to 26 healthy controls who had no history of suffering from fibromyalgia or any other rheumatological or neurological illness. Results: The groups were matched in respect of age, sex and ethnicity. None of the 53 subjects was taking medication, which might cause urinary urgency, none was suffering from, or had recently suffered from, a urinary tract infection and none had undergone a previous operative procedure on the lower urinary tract. Twenty-five (93%) patients had evidence of an overactive bladder during the previous four weeks, compared with five (19%) of the control group (p < 0.001). In terms of symptom severity, the mean (standard error) OAB-q8 score was 24.4 (1.5) in the fibromyalgia patients and 10.8 (4.5) in the controls (p < 0.001). Furthermore, the total OAB-q8 and FIQR scores were positively correlated (rs = 0.727, p < 0.001). Conclusion: This systematic controlled study confirms that fibromyalgia is associated with overactive bladder symptoms. The relatively high prevalence of 93% indicates that overactive bladder is an important urological association of fibromyalgia and should be routinely assessed in these patients.