Interstitial Cystitis Data Base Study Research Articles

Management of Bladder Pain Syndrome: Green-top Guideline No. 70.

Management of Bladder Pain Syndrome: Green-top Guideline No. 70.

Gender Specific Pelvic Pain Severity in Neurogenic Cystitis

Interstitial cystitis/painful bladder syndrome is a chronic bladder inflammatory disease of unknown etiology that is often regarded as neurogenic cystitis. The condition is associated with focal inflammation, urothelial lesions, voiding dysfunction and pain in the pelvic/perineal area. Approximately 90% of patients with the condition are women, suggesting the possibility of hormonal involvement in interstitial cystitis/painful bladder syndrome symptoms. We examined the basis of gender specific pelvic pain in a murine model of neurogenic cystitis that recapitulates features of interstitial cystitis/painful bladder syndrome and in which pelvic pain is mediated by mast cell histamine. Murine neurogenic cystitis was induced by tail base inoculation of C57BL/6 or BALB/c mice with the Bartha strain of pseudorabies virus. Pelvic pain behavior was assessed by quantifying tactile allodynia in response to mechanical stimulation with von Frey filaments. Bladder mast cells were quantified by flow cytometry. Female mice of each genetic background showed significantly greater pelvic pain behavior than males, although responses were greater in BALB/c females. Gender specific pelvic pain behavior did not correspond to increased bladder inflammation or barrier dysfunction. Modulating reproductive hormonal status by ovariectomy and subsequent estrogen replacement had no effect on the magnitude of pseudorabies virus induced pain. The number of mast cells was associated with pelvic pain severity in female mice but it did not correlate with gender specific pelvic pain. These data suggest that pelvic pain in mice with murine neurogenic cystitis is mediated by gender specific responsiveness to mast cells while pelvic pain severity is modulated by genetic factors.

A Prospective Early History of Incident Interstitial Cystitis/Painful Bladder Syndrome

The longitudinal history of interstitial cystitis/painful bladder syndrome has been studied infrequently. In a national sample of incident cases we assessed changes in symptoms during the first several years of interstitial cystitis/painful bladder syndrome. We recruited 312 women with a history of interstitial cystitis/painful bladder syndrome symptoms of 12 months or less and interviewed them by telephone at baseline, and 6, 12, 18, 24, 36 and 48 months later. We queried symptoms in the last week and interval medication use. Individual and composite symptom categories were constructed. The median history of symptoms at study enrollment was 9 months. Median followup was 33 months after onset. The 57 study withdrawals (18%) were not substantively different than those remaining in followup. Many cases of severe and moderate interstitial cystitis/painful bladder syndrome at enrollment improved with time. As followup progressed, increasing proportions reported improvement while decreasing proportions reported symptom worsening. Of the women 27 (9%) reported at least temporary symptom remission. Of 304 women with incident interstitial cystitis/painful bladder syndrome 35% reported improvement from baseline in symptoms at last followup a median of 33 months after onset. However, the disappearance of all symptoms at any followup was uncommon.

Interstitial Cystitis/Painful Bladder Syndrome and Associated Medical Conditions With an Emphasis on Irritable Bowel Syndrome, Fibromyalgia and Chronic Fatigue Syndrome

We characterized and compared the impact of clinical phenotypic associations between interstitial cystitis/painful bladder syndrome and controls in relation to potentially related conditions, particularly irritable bowel syndrome, fibromyalgia and chronic fatigue syndrome. Female patients with interstitial cystitis/painful bladder syndrome and controls with no interstitial cystitis/painful bladder syndrome completed a biopsychosocial phenotyping questionnaire battery which included demographics/history form, self-reported history of associated conditions, and 10 validated questionnaires focused on symptoms, suffering/coping and behavioral/social factors. Questionnaires were completed by 205 patients with interstitial cystitis/painful bladder syndrome and 117 controls matched for age. Prevalence of self-reported associated condition diagnosis in interstitial cystitis/painful bladder syndrome vs controls was irritable bowel syndrome 38.6% vs 5.2%, fibromyalgia 17.7% vs 2.6% and chronic fatigue syndrome 9.5% vs 1.7% (all p <0.001). In the interstitial cystitis/painful bladder syndrome cohort 50.3% reported no other associated condition, 24.4% had interstitial cystitis/painful bladder syndrome + irritable bowel syndrome only, 2.5% had interstitial cystitis/painful bladder syndrome + fibromyalgia only, 1.5% had interstitial cystitis/painful bladder syndrome + chronic fatigue syndrome only, while 20.2% had multiple associated conditions. As the number of associated conditions increased (ie localized, regional, systemic), pain, stress, depression and sleep disturbance increased while social support, sexual functioning and quality of life deteriorated. Anxiety and catastrophizing remained increased in all groups. Symptom duration was associated with this apparent phenotypic progression. Irritable bowel syndrome, fibromyalgia and chronic fatigue syndrome are more prevalent in patients with interstitial cystitis/painful bladder syndrome than in asymptomatic control subjects, and result in significant impact. There are at least 3 distinct clinical phenotypes based on identification of overlapping syndrome patterns. A suggestion that remains to be proven with longitudinal studies is that there may be progression over time from an organ centric to a regional and finally to a systemic pain syndrome with progression of symptom severity, and deterioration of cognitive and psychosocial parameters.

Sites of Pain From Interstitial Cystitis/Painful Bladder Syndrome

In interstitial cystitis/painful bladder syndrome multiple pain sites are common. We hypothesized that a careful and systematic description of the pain of interstitial cystitis/painful bladder syndrome might provide clues to its pathogenesis. Women with 12 months or greater of interstitial cystitis/painful bladder syndrome symptoms underwent a medical record review and interview. Each completed a questionnaire that included views of the female body and described up to 5 interstitial cystitis/painful bladder syndrome pains, noting 40 descriptors for each. Two-thirds of the 226 patients reported multiple pains. Pain could be consolidated at 4 sites, including suprapubic, urethral, genital and nongenitourinary. Most descriptors were similar and little evidence indicated that 1 pain influenced pain at another site. Another 3 patterns were evident, including 1) a suprapubic > urethral > genital > nongenitourinary ranking in site distribution and at each site proportions that were solitary, the worst and the most frequent pains, and pains that responded to bladder events, 2) site specific allodynia, and 3) for urethral and genital pains a wider spectrum of sensations, including burning, stinging and sharp. Patients with urethral (38%) or genital (27%) pain did not differ from those without such pain in 95% of 44 important characteristics. Suprapubic prominence and changes in the voiding cycle are features consistent with but do not prove that the bladder is the pain generator in interstitial cystitis/painful bladder syndrome and the pain sites described by patients are referred from it. The patients with interstitial cystitis/painful bladder syndrome who might have been diagnosed with vulvodynia or urethral syndrome did not differ from others in important patient variables.

Discovery of Morphological Subgroups That Correlate With Severity of Symptoms in Interstitial Cystitis: A Proposed Biopsy Classification System

We identified morphologically distinct subgroups in interstitial cystitis using cluster analysis and investigated the associations between cluster membership and urinary symptoms. Of 637 patients enrolled in the Interstitial Cystitis Data Base Study 203 (32%) provided bladder biopsies at baseline screening, representing the focus of this analysis. A cluster analysis algorithm implemented in SAS PROC CLUSTER using standardized distances to measure the dissimilarity of each pair of patients with respect to select histopathological features was used to construct subgroups of these patients. Multivariate regression models for baseline nighttime and 24-hour voiding frequency, urinary urgency and pain were developed, incorporating indicator variables for cluster membership as predictors. Longitudinal urinary symptom profiles during 3 years of followup were also compared among the morphology clusters. Three morphology clusters were identified, corresponding to unique pathological groupings. In cluster C2 7 patients showed multiple pathological features of parenchymal damage, including several inflammatory features. In cluster C1 17 patients was characterized by complete denudation of the urothelium and variable edema. In cluster C0 in 179 patients none of the pathological features were present above the specified thresholds for C2. Cluster membership was significantly associated with baseline nighttime and 24-hour frequency (p <0.001, and with urinary urgency (p = 0.03). These significant increases in baseline symptom severity among clusters from C0 to C1 to C2 persisted throughout the 3 years of followup. These results suggest an important role for histopathological features in the predictive modeling of interstitial cystitis symptoms.

Predictors of Symptom Severity in Patients With Chronic Prostatitis and Interstitial Cystitis

Numerous studies have been performed to identify potential risk factors for CP/CPPS and IC. However, few studies have been done to identify predictors of disease severity. A total of 174 men with CP/CPPS and 111 women with IC completed questionnaires to quantify symptom severity and identify demographic, medical and psychosocial characteristics. Symptom severity was assessed with the National Institutes of Health CPSI in men, and the O'Leary-Sant ICSI and problem index in women. Univariate and multivariate analyses were performed to identify characteristics predictive of worse symptoms. The mean National Institutes of Health CPSI score in men was 15.32, and the mean O'Leary-Sant ICSI and problem index in women was 19.17. The most commonly reported comorbidities were allergies, sinusitis, erectile dysfunction and irritable bowel syndrome in men, and allergies, urinary incontinence, sinusitis and irritable bowel syndrome in women. In the 2 sexes self-reported urinary frequency and urgency, worse depression scores and lower education level were independent predictors of worse symptom severity. In men additional independent predictors were self-reported pelvic pain, fibromyalgia and previous heart attack, and in women an additional independent predictor was postmenopausal status. There are several common medical conditions associated with urological pelvic pain syndromes in men and women. Few of them were predictive of symptoms severity in this analysis. Self-reported pelvic pain symptoms, education and depression severity were the factors most strongly predictive of symptom severity in patients with CP/CPPS and IC.

INTERSTITIAL CYSTITIS, CHRONIC NONBACTERIAL PROSTATITIS AND CHRONIC PELVIC PAIN SYNDROME IN MEN: A COMMON AND FREQUENTLY IDENTICAL CLINICAL ENTITY

In this ongoing review we characterize interstitial cystitis in men, identifying multiple clinical factors in the diagnosis and treatment of men with interstitial cystitis. An ongoing and retrospective chart review of 92 men with interstitial cystitis within our large single specialty practice was performed. Presenting complaints, duration of symptoms, epidemiology, and clinical and physical findings were reviewed. All patients met National Institute for Diabetes and Digestive and Kidney Diseases criteria for the diagnosis of interstitial cystitis. Of the patients 83% were white and 17% were American Indians of Cherokee descent. Average patient age at diagnosis was 51 years and average duration of symptoms was 8.8 years. The most commonly reported initial complaints were mild suprapubic discomfort, which rapidly progressed in an average of 21/2 years to severe suprapubic discomfort, severe dysuria and severe urinary frequency. Sexual dysfunction occurred in 60% of patients with painful ejaculation. The most common physical findings were suprapubic tenderness to palpation and anterior rectal wall tenderness on digital rectal examination. Of the patients 40% had microscopic hematuria. All patients demonstrated severe glomerulations under anesthesia with cystoscopy and hydraulic distention of the bladder. Average bladder volume was 510 cc. Interstitial cystitis in males appears to be more common than historically reported. Interstitial cystitis in males and patients with chronic pelvic pain syndrome and chronic nonbacterial prostatitis share many clinical findings. A higher incidence of interstitial cystitis had been found in American Indian males of Cherokee descent and deserves further investigation.

IS URINE METHYLHISTAMINE A USEFUL MARKER FOR INTERSTITIAL CYSTITIS?

We determined whether urine methylhistamine (MH) is associated with other clinical features and bladder biopsy findings in interstitial cystitis (IC). Urine MH and University of Wisconsin symptom scores were measured before and 1 month after bladder distention for IC. Bladder biopsies were done at the time of distention. In new patients with IC who met cystoscopic criteria urine MH was compared before and after distention, and changes in urine MH were compared with changes in symptom scores. Pre-distention urine MH was tested for associations with the results of a symptom questionnaire, symptom response after distention, cystoscopic findings and bladder biopsy findings. There were no significant associations between urine MH and symptom scores, response to bladder distention, cystoscopic findings or bladder biopsy features, including mast cell count by tryptase staining. Urine MH was similar in new patients with IC who did vs did not meet cystoscopic criteria. Urine MH was similar in new vs chronically treated patients with IC. Urine MH is unlikely to be useful as an objective marker of the response to bladder distention, as a method to predict which patients will respond to bladder distention or as a noninvasive substitute for bladder biopsy and mast cell counts by tryptase staining.

Biopsy features are associated with primary symptoms in interstitial cystitis: results from the interstitial cystitis database study

The purpose of this study was to investigate associations between bladder biopsy features and urinary symptoms for patients enrolled in the Interstitial Cystitis Database (ICDB) Study. Bladder biopsies were obtained during baseline screening in the ICDB Study and were evaluated for histopathologic features. Multivariable models for nighttime voiding frequency, urinary urgency, and pain were developed, incorporating biopsy features from the most diseased area of the bladder as predictors, adjusting for significant clinical factors, and clinical center variation. Among 204 interstitial cystitis (IC) patients providing biopsy specimens, cystoscopic pathology findings were not statistically associated ( P >0.1) with primary IC symptoms, although the presence of Hunner’s ulcer (n = 12) was suggestive of increased urinary frequency. Within a multivariable predictive model for nighttime voiding frequency, adjusting for age and minimum volume per void, 4 pathology features were noted: (1) mast cell count in lamina propria on tryptase stain; (2) complete loss of urothelium; (3) granulation tissue in lamina propria; and (4) vascular density in lamina propria on factor VIII (F8) stain were statistically significant ( P <0.01). Similarly, in a multivariable model for urinary urgency, minimum volume, and percentage of submucosal granulation tissue remained statistically significant ( P <0.01). Finally, the percentage of mucosa denuded of urothelium and the percentage of submucosal hemorrhage remained highly associated ( P <0.01) with pain in a multivariable predictive model. The fact that the presence or severity of glomerulations was not selected for any of these predictive models suggests that cystoscopic findings of glomerulations are not predictive of IC symptoms. Furthermore, these results suggest an important role for certain pathologic features in the predictive modeling of IC symptoms.

Daily stress and symptom exacerbation in interstitial cystitis patients

Stress-related exacerbation of interstitial cystitis (IC) symptoms has been frequently reported. Previous research has found stress-related IC symptom exacerbation in an experimental model. However, this relation has not been objectively examined with daily life stressors. We used a prospective daily symptom diary methodology to investigate relations between stress and bladder symptoms in IC patients and age-matched healthy controls. A total of 45 previously diagnosed female IC patients completed a bladder symptom and stress diary nightly for 1 month; 31 female age-matched healthy controls completed a similar diary for 7 days. Symptom questions were modified from the Interstitial Cystitis Database study. Patients reported greater mean daily stress, bladder pain, urgency, daytime and nocturnal frequency than controls (all P-values ,0.001). Among all patients, a significant relationship between stress and urgency was observed. In addition, a significant relation between stress and pain was observed among patients with moderate and severe disease. As disease severity increased, more pronounced relations between stress and the symptoms of urgency and pain were evidenced. Greater stress was associated with greater nocturnal frequency among patients with more severe disease. These stress-symptom relations were not observed among controls. Higher levels of stress were related to greater pain and urgency in IC patients but not in controls. In addition, the relation of stress and these IC symptoms was stronger among patients with more severe symptomatology. This study indicates that life stress is associated with greater IC symptoms, particularly among patients whose disease is not well controlled.

Stress and symptoms in patients with interstitial cystitis: a life stress model

Objectives. Stress-related exacerbation of interstitial cystitis (IC) symptoms has frequently been reported. Previous research has found stress-related IC symptom exacerbation in an experimental model. However, this relationship has not been objectively examined with daily life stressors. We used a prospective daily symptom diary method to investigate the relationships among stress and bladder symptoms in patients with IC and age-matched healthy controls. Methods. Forty-five previously diagnosed female patients with IC completed a bladder symptom and stress diary nightly for 1 month; 31 female age-matched healthy controls completed a similar diary for 7 days. The symptom questions were modified from the Interstitial Cystitis Data Base study. Results. Patients reported greater mean daily stress, bladder pain, urgency, and daytime and nocturnal frequency than controls (all P values less than 0.001). Among all patients, a significant relationship between stress and urgency was observed. In addition, a significant relationship between stress and pain was observed among patients with moderate and severe disease. As the disease severity increased, more pronounced relationships between stress and the symptoms of urgency and pain were evidenced. Greater stress was associated with greater nocturnal frequency among patients with more severe disease. These stress-symptom relationships were not observed among the controls. Conclusions. Higher levels of stress were related to greater pain and urgency in patients with IC but not in the controls. In addition, the relationship of stress and these IC symptoms was stronger among patients with more severe disease. The results indicate that life stress is associated with greater IC symptoms, particularly among patients whose disease is not well controlled.

BLADDER EPITHELIAL CELLS FROM PATIENTS WITH INTERSTITIAL CYSTITIS PRODUCE AN INHIBITOR OF HEPARIN-BINDING EPIDERMAL GROWTH FACTOR-LIKE GROWTH FACTOR PRODUCTION

The etiology of interstitial cystitis is unknown. We previously identified an interstitial cystitis urine factor, antiproliferative factor, that inhibits proliferation of bladder epithelial cells in vitro and complex changes in epithelial growth factor levels, including profound decreases in heparin-binding epidermal growth factor-like growth factor (HB-EGF). Bladder and renal pelvic catheterization of patients with interstitial cystitis indicated that the antiproliferative factor is made and/or activated in the distal ureter or bladder. Therefore, we determined whether bladder epithelial cells from interstitial cystitis cases produced the antiproliferative factor and whether purified antiproliferative factor could alter production of growth factors known to be abnormal in interstitial cystitis. Antiproliferative factor activity was determined by 3H-thymidine incorporation into primary bladder epithelial cells. The antiproliferative factor was purified by size fractionation followed by sequential chromatography involving ion exchange, hydrophobic interaction and high performance liquid chromatography. HB-EGF, epidermal growth factor, insulin-like growth factor and insulin-like growth factor binding protein 3 levels were determined by enzyme-linked immunosorbent assay. Bladder epithelial cells from patients with interstitial cystitis produced a single antiproliferative factor with the same purification profile as that purified from interstitial cystitis urine. Purified antiproliferative factor specifically inhibited HB-EGF production by bladder epithelial cells in vitro, and the effect of interstitial cystitis urine or purified antiproliferative factor on bladder cell proliferation was inhibited by recombinant human HB-EGF in a dose dependent manner. Similar to urine HB-EGF, serum HB-EGF was also significantly lower in interstitial cystitis cases than in controls. Bladder epithelial abnormalities in interstitial cystitis may be caused by a negative autocrine growth factor that inhibits cell proliferation by down-regulating HB-EGF production. Furthermore, decreased levels of urine and serum HB-EGF indicate that interstitial cystitis may be a urinary tract manifestation of a systemic disorder.

QUALITY OF LIFE AMONG WOMEN WITH INTERSTITIAL CYSTITIS

Clinical case series suggest that the impact of interstitial cystitis on quality of life is severe and debilitating, however, little epidemiologic information is available. We examined the impact of interstitial cystitis on quality of life in a population based cohort of United States women. We collected multidimensional measures of quality of life from 159,419 participants in the Nurses' Health Study I and II using a validated instrument, the Medical Outcome Study Short-Form 36 Health Survey Instrument. This instrument measures physical function, role limitations due to physical and emotional problems, bodily pain, vitality, social function and mental health. Quality of life measures were collected on 99 women with prevalent self reported interstitial cystitis confirmed by medical record review. After adjusting for age and co-morbid conditions, women with interstitial cystitis had significantly lower quality of life scores in 4 of the 7 quality of life dimensions, including role/physical (beta -13.1, p <0.001), bodily pain (beta -9.8, p <0.001), vitality (beta -7.7, p <0.001) and social function (beta -7.2, p <0.001) compared to women without interstitial cystitis. Women with interstitial cystitis experienced less decrement in physical function compared to women with rheumatoid arthritis but more compared to women with hypertension. In addition, they experienced greater differences in vitality and mental health than women with rheumatoid arthritis or hypertension. The quality of life among women with interstitial cystitis was especially limited in the psychosocial dimensions, such as vitality and mental health. Future research on interstitial cystitis should incorporate multidimensional measures of quality of life, especially with respect to response to the various treatments.

A PROSPECTIVE STUDY OF INTERSTITIAL CYSTITIS: RESULTS OF LONGITUDINAL FOLLOWUP OF THE INTERSTITIAL CYSTITIS DATA BASE COHORT

We present baseline characteristics and longitudinal profiles of symptoms in the Interstitial Cystitis Data Base study, a prospective cohort study of patients with interstitial cystitis. A total of 637 eligible patients were entered into the study and followed for symptoms of pain, urgency and urinary frequency. Median followup was 31 months. More than 90% of patients were white women with a median age of 43 years. Using the overall pain-urgency-frequency score 7% of participants presented with mild, 44% with moderate and 49% with severe symptoms. Severe urgency in 41% of cases and severe 24-hour frequency in 41% were more common than severe pain in 29%. Of the patients 51% reported nighttime frequency of 2 or more voids. Median duration of interstitial cystitis symptoms was 8 years and 68% of participants were previously diagnosed with the condition. The 36% of patients who withdrew from study or were lost to followup were more likely to have had more severe symptoms at baseline. Patterns of change with time suggest initial symptom improvement due to regression to the mean, and an intervention effect associated with the increased followup and care of cohort participants. Although all symptoms fluctuated, there was no evidence of significant long-term change in overall disease severity. Our observations support the clinical observation that interstitial cystitis is a chronic disease and no current treatments have a significant impact on symptoms with time. These results provide a foundation for the design and performance of future clinical trials in interstitial cystitis using these end points in a similar patient population.

EVALUATION OF REPEAT DAILY VOIDING MEASURES IN THE NATIONAL INTERSTITIAL CYSTITIS DATA BASE STUDY

We address the importance of 3 consecutive daily frequency volume charts relative to a single day in research studies for interstitial cystitis. In addition, differences in voiding patterns between weekend days and weekdays were evaluated. Longitudinal frequency volume chart data for 305 women enrolled in the National Interstitial Cystitis Data Base Study before December 31, 1995 and meeting protocol specifications were summarized for 3 outcome measures. Longitudinal data methods designed to accommodate different within patient correlation patterns for repeat measures within and among patient contacts were implemented in a generalized estimating equation modeling framework, permitting overall testing of day and weekend effects. Day 2 and day 3 measures were not statistically different (1% level) from day 1 for nocturnal voiding frequency and nocturia. Although statistically significant for 24-hour frequency, the mean difference of -0.36 void daily between days 1 and 3 was not likely to be clinically significant. Also, measures on weekdays were not significantly different from those on weekends for each of the 3 outcome measures. Our results suggest that the current clinical research requirement of 3 consecutive days for frequency volume charts can be reduced to a single day. Furthermore, day selection need not be affected by weekday versus weekend considerations.

A RANDOMIZED DOUBLE-BLIND TRIAL OF ORAL L-ARGININE FOR TREATMENT OF INTERSTITIAL CYSTITIS

Nitric oxide synthase activity is decreased in the urine of patients with interstitial cystitis compared to the urine of controls. In a preliminary trial oral L-arginine, the substrate for nitric oxide synthase, increased urinary nitric oxide synthase activity and improved interstitial cystitis symptoms. This randomized, double-blind, placebo controlled study further investigates the efficacy of L-arginine treatment for interstitial cystitis. A total of 53 interstitial cystitis patients were assigned to receive daily 1,500 mg. L-arginine or placebo orally for 3 months. Interstitial cystitis symptoms were assessed by interviews at 2 weeks, and 1, 2 and 3 months. The trial was completed by 21 of 27 patients in the L-arginine group and 25 of 26 in the placebo group. Using per protocol analysis 29% (6 of 21 patients) in the L-arginine group and 8% (2 of 25) in the placebo group were clinically improved by the end of the trial (p = 0.07). A Likert scale showed greater global improvement in the L-arginine group (48%, 10 of 21) compared to the placebo group (24%, 6 of 25) at 3 months (p = 0.05) with a decrease in pain intensity (p = 0.04), and tendency toward improvement in urgency (p = 0.06) and frequency of pain (p = 0.09). Using an intention to treat approach to analysis there were no differences between groups. Oral L-arginine (1,500 mg. daily) may decrease pain and urgency in a subset of interstitial cystitis patients.

THE DIAGNOSIS OF INTERSTITIAL CYSTITIS REVISITED: LESSONS LEARNED FROM THE NATIONAL INSTITUTES OF HEALTH INTERSTITIAL CYSTITIS DATABASE STUDY

The lack of a precise working definition of interstitial cystitis may have resulted in the de facto use of the National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) "research" definition by clinicians. We evaluated these strict criteria in light of the broader inclusion criteria for patients evaluated in the Interstitial Cystitis Database study to determine their utility in clinical practice as a useful basis for the diagnosis of interstitial cystitis. A total of 379 women who completed screening for the Interstitial Cystitis Database before January 1, 1996 met the basic criteria of urinary frequency, urgency or pain for at least 6 months in duration without a diagnosable etiology. Of these patients 148 underwent cystoscopy and hydrodistention of the bladder as a part of the evaluation. All patients were followed for a minimum of 1 year. Comparisons were made between patients judged to have a clinical diagnosis of interstitial cystitis and those who met the NIDDK research definition of the syndrome. Almost 90% of patients potentially meeting NIDDK criteria are believed by experienced clinicians to have interstitial cystitis, confirming the research value of these criteria in defining a homogeneous population for study. However, strict application of NIDDK criteria would have misdiagnosed more than 60% of patients regarded by researchers as definitely or likely to have interstitial cystitis. The NIDDK criteria are too restrictive to be used by clinicians as the diagnostic definition of interstitial cystitis.

The interstitial cystitis data base study: Concepts and preliminary baseline descriptive statistics

Objectives To describe the design, patient population, and data and specimen collection aspects of the Interstitial Cystitis Data Base (ICDB) Study and to provide preliminary descriptive statistics and inferential results from an interim analysis. Methods All 424 study participants successfully enrolled in the ICDB Study prior to December 31, 1995, were selected for an interim analysis and were classified into 1 of 3 symptom severity subgroups. Statistical tests for associations among these symptom severity subgroups and a broad range of baseline characteristics were conducted using Mantel-Haenszel procedures to adjust for variation among clinical centers. Results ICDB Study patients are predominantly female (91.5%), white (91.0%), with an average age at enrollment of 44.3 years. Nearly 45% of these patients underwent a cystoscopy at baseline screening, among whom there was an overall prevalence of 10.5% for Hunner's patch and 90% for glomerulations. Urodynamic evaluation for the entire 424 patients demonstrated that volumes at first sensation and at maximal capacity were inversely associated with symptom severity subgroups. A broad range of symptoms were analyzed, indicating that nearly 40% of patients reported urinating 15 times or more during awake hours, and more than 20% reported voiding at least 4 times per night. Almost half (47.9%) reported constant urgency and 23.6% reported having severe pain. Patients in the severe symptom subgroup reported greater limitations in selected quality-of-life indicators than those with less severe symptoms. Conclusions This interim analysis of the ICDB Study data was compared to previous epidemiologic studies of IC and provides an essential foundation for further analytic investigations of baseline associations and longitudinal trends.