{"paper_id":"33cb733b-e6c8-4107-8bb0-582a62abee92","body_text":"Abstract\nIntroduction: Recent literature indicates that interstitial cystitis (IC) may affect 20% of women and a smaller proportion of men, although many individuals with IC may be misdiagnosed or remain undiagnosed. Factors that can contribute to the cost of IC include medical and drug utilisation related to treatment and diagnosis of IC and associated conditions (e.g. depression), as well as employee work loss. This study assesses the direct medical cost and indirect cost of work loss for IC patients in the first year after diagnosis, and evaluates IC treatment patterns and prevalence of co-morbidities.\nMethods: Data for patients under the age of 65 years with at least one diagnosis of IC (n = 749) were drawn from a de-identified, administrative database of approximately 2 million beneficiaries that included medical, drug and disability claims for 1999–2002. A 2: 1 matched control sample of patients without an IC diagnosis (non-IC sample) was randomly selected based on patient characteristics. Indirect costs were calculated from a subgroup of 152 IC patients (plus their matched controls) who had disability information available.\nCosts incurred in the first year after IC diagnosis and co-morbidities were compared between IC patients and the non-IC sample, with the difference in costs defined as ‘excess costs’ of IC patients. Treatment patterns were profiled in the 2 months following initial diagnosis of IC. Descriptive statistics are presented. A multivariate two-part model was applied to estimate the IC direct medical cost, indirect cost and total cost to adjust for observed patient demographics and comorbidities. Statistical significance was evaluated by the bootstrap method.\nResults: The average IC patient had 130% higher direct costs (p < 0.05) and the average IC employee patient had 84% higher indirect costs than the average non- IC control individual. IC patients also had a higher diagnostic prevalence of prostatitis (relative risk [RR] = 40.0), endometriosis (RR = 7.4), vulvodynia (RR = 6.9), chronic pelvic pain (RR = 5.8) and urinary tract infections (RR = 5.1) [all p < 0.05]. IC patients were also more likely to report depression (RR = 2.8) and anxiety (RR = 4.5 ) than non-IC controls (all p < 0.05).\nSeventeen percent of IC patients received pentosan polysulfate therapy, the only US FDA-approved oral drug therapy indicated for treating IC, within the first 2 months after diagnosis. Of these patients, 69% received at least one ‘other’ drug from the non-approved oral medications studied. Approximately one-third of IC patients received only ‘other’ drug therapies, and almost half of IC patients received no drug treatment within the first 2 months after the initial diagnosis.\nConclusions: IC is a costly disease associated with co-morbidities. Following diagnosis, patients with IC are commonly untreated or treated with non-approved drug therapies. It is possible that more accurate diagnosis and earlier and more appropriate treatment of IC would lead to better management (or even prevention) of co-morbidities and reduce healthcare costs, and this should be investigated in future studies.\nSimilar content being viewed by others\nReferences\nHenderson L. Diagnosis, treatment, and lifestyle changes of interstitial cystitis. AORN J 2000 Mar; 71 (3): 525–38\nMessing E. Interstitial cystitis and related syndromes. In: Walsh PC, Retik AB, Stameey TA, et al., editors. Campbell’s urology. Philadelphia (PA): WB Saunders Co., 1992: 982\nGillenwater JY, Wein AJ. Summary of the National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases Workshop on Interstitial Cystitis. National Institutes of Health. Bethesda (MD), 1987 Aug 28-9. J Urol 1988; 140: 203–6\nMelts J. Interstitial cystitis: urgency and frequency syndrome. Am Fam Physician 2001 Oct; 64 (7): 1199–206\nParsons CL, Dell J, Stanford EJ, et al. Increased prevalence of interstitial cystitis: previously unrecognized mologic and gynecologic cases identified using a new symptom questionnaire and intravesical potassium sensitivity. Urology 2002; 60: 573–8\nKoziol JA, Clark DC, Gilles RE et al. The natural history of interstitial cystitis: a survey of 374 patients. J Urol 1993; 149: 465–9\nKoziol JA. Epidemiology of interstitial cystitis. Urol Clin North Am 1994; 21: 7–20\nBurkman RT. Chronic pelvic pain of bladder origin: epidemiology, pathogenesis and quality of life. J Reprod Med 2004; 49: 225–9\nRatner V, Taylor N, Wein AJ, et al. Re: epidemiology of interstitial cystitis. A population based study [comment]. J Urol 1999; 162: 500\nMathias SD, Kuppermann M, Liberman RF, et al. Chronic pelvic pain: prevalence, health-related quality of life, and economic correlates. Obstet Gynecol 1996; 87: 321–7\nPropert KJ, Schaeffer AJ, Brensinger CM, et al. A prospective study of interstitial cystitis: results of longitudinal follow-up of the interstitial cystitis database cohort. The Interstitial Cystitis Data Base Study Group. J Urol 2000; 163: 1434–9\nHanno PM, Landis JR, Matthews-Cook Y, et al. The diagnosis of interstitial cystitis revisited: lessons learned from the National Institutes of Health Interstitial Cystitis Database study. J Urol 1999; 161: 553–7\nMichael YL, Kawachi I, Stampfer MJ, et al. Quality of life among women with interstitial cystitis. J Urol 2000; 164: 423–7\nBarger M, Woolner B. Primary care for women: assessment and management of genitourinary tract disorders. J Nurse Midwifery 1995; 40: 231–45\nRatner V, Slade D, Greene G. Intersitial cystitis: a patient’s perspective. Urol Clin North Am 1994 Feb; 21: 1–5\nInterstitial Cystitis Association. What is IC? Interstitial cystitis factsheet. 2003 [online]. Available from URL: http://www. ichelp.com/whatisic/icfactsheet.html [Accessed 2005 Nov 25]\nMullahy J. Much ado about two: reconsidering retransformation and the two-part model in health econometrics. J Health Econ 1998; 17: 247–81\nManning WG. The logged dependent variable, heteroscedasticity, and the retransformation problem. J Health Econ 1998; 17: 283–95\nEfron B, Tibshirani R. Bootstrap methods for standard errors, confidence intervals, and other measures of statistical accuracy. Stat Sci 1986; 1: 54–77\nWhite A, Birnbaum HG, Mareva MN, et al. Economic burden of illness for employees with painful conditions. J Occup Environ Med 2005 Sep; 47 (9): 884–92\nAcknowledgements\nThis research was funded by an unrestricted research grant from Ortho Women’s Health & Urology, Division of Ortho-McNeil Pharmaceutical, Inc.\nEric Wu, Howard Birnbaum and Andrew Parece prepared the analysis plan, supervised the analysis and were responsible for writing the manuscript. Milena Mareva and Zihong Huang conducted the analysis and prepared the programmes. David Mallett provided the data, addressed data issues and reviewed the manuscript. Haya Taitel conceived of the study, provided input into the analysis and reviewed the manuscript. Eric Wu, Howard Birnbaum, Andrew Parece, Milena Mareva and Zihong Huang were employed by Analysis Group at the time of this research, and David Mallett was employed by Ingenix. Haya Taitel was employed by Ortho-McNeil Phamaceutical at the time of this research.\nAuthor information\nAuthors and Affiliations\nCorresponding author\nRights and permissions\nAbout this article\nCite this article\nWu, E.Q., Birnbaum, H., Mareva, M. et al. Interstitial cystitis. Pharmacoeconomics 24, 55–65 (2006). https://doi.org/10.2165/00019053-200624010-00005\nPublished:\nIssue date:\nDOI: https://doi.org/10.2165/00019053-200624010-00005","source_license":"public-domain-us","license_restricted":false}