Interstitial cystitis/bladder pain syndrome (IC/BPS) is a common, painful disease of the urinary bladder. Difficult to diagnose and frequently misdiagnosed as another common urologic disorder, IC/BPS challenges health care providers to identify it early and implement current treatment algorithms that may simplify management and improve quality of life for affected patients.
Interstitial cystitis (IC), or bladder pain syndrome (BPS), is a clinical condition characterized by bladder pain, urinary frequency and urgency, and increased nighttime urination (nocturia).1 More specifically, IC/BPS is defined as an unpleasant sensation in the bladder, abdomen, or pelvis (ie, pain, pressure, burning, and/or other discomfort) perceived to be originating in the urinary bladder. The condition is associated with lower urinary tract symptoms of more than six weeks’ duration, with no infection or other identifiable cause present.2
IC/BPS lacks a single known etiology; rather, it most likely results from multiple contributing factors that cascade into a painful and potentially debilitating syndrome. The condition was first described more than a century ago,3,4 but its complex nature and conflicting theories about its pathogenesis present both diagnostic and therapeutic challenges for health care professionals. Frequent misdiagnosis of IC/BPS as another common urologic disorder can make timely, appropriate treatment elusive.
Without a clearly described pathophysiology, IC/BPS has always been difficult to define using standardized diagnostic criteria and precise terminology. The definition of the condition was revised in 2002 and again in 2008, when the nomenclature bladder pain syndrome was introduced.1,5,6
Less than 10 years ago, US researchers described IC as a subgroup of BPS,7 while in Europe, BPS is used as the broader term, with IC still considered a well-defined subgroup that usually involves ulceration.6 The future may find IC, BPS, and painful bladder syndrome (PBS) used as interchangeable terms—or as unique diagnoses. A better understanding of the pathophysiology of IC/BPS/PBS would contribute not only to resolving issues of nomenclature, but also to establishing an accurate diagnosis earlier in the disease process and providing more efficient, effective treatment.
THE PROBLEM OF EPIDEMIOLOGY
Inconsistencies in the terminology, definitions, and diagnostic criteria of IC/BPS have made epidemiology difficult to establish.1 It has been suggested that IC/BPS is underdiagnosed in the United States and that its prevalence is much greater than generally reported.8
According to one study of IC in a managed care population, its prevalence in 2005 was 197 per 100,000 women and 41 per 100,000 men, with the female-to-male ratio estimated at 5:1.9 In 2011, researchers for the RAND Corporation published what they called the first population-based “symptom prevalence estimate” among US women older than 18, based on more than 100,000 screening interviews conducted by phone. According to their findings, between 3.3 and 7.9 million US women meet the stated criteria for IC/BPS (ie, between 3,113 and 7,453 women per 100,000).10 These conflicting data exemplify the range of epidemiologic conclusions that exist regarding this condition.
On the next page: Proposed pathophysiology >>