Prevalence of self-reported interstitial cystitis (IC) and interstitial-cystitis-like symptoms among adult women in the community.

Purpose: Reported estimates of IC prevalence vary widely. The objective of this study is to determine the prevalence of IC among community-dwelling adult women.

Methods: We analyzed survey responses from 215 established IC cases and 823 age-matched community-dwelling controls. Using a history of diagnosis of urinary conditions and presence of pelvic pain within the last six months, we identified those with possible IC among the controls using various operative definitions.

Results: The prevalence rates of self-reported IC (SRIC) and IC-like symptoms (ICLS) among controls in the community were 3.7% and 4.4%, respectively. Expanding ICLS by including women who reported pelvic pain only raised the prevalence to 17.3%.

Conclusions: According to our prevalence rates and population estimates in the United States census 2000, the number of adult women who possibly have interstitial cystitis is estimated to be between 422,803 and 21,454,813. Although estimates based on the question of having ever been diagnosed with IC lead to an estimate close to that derived from symptoms, underestimation of IC prevalence might occur in the absence of additional questions and testing to validate and qualify the responses further. There is also a need for clinical studies to verify and validate the diagnoses to enable accurate assessment of the sensitivity and specificity of such history survey questions.