The Economic Impact of Irritable Bowel Syndrome

J. M. Inadomi, M. B. Fennerty, D. Bjorkman

Disclosures

Aliment Pharmacol Ther. 2003;18(7) 

In This Article

Discussion

The costs of managing irritable bowel syndrome are considerable, although the precise impact remains elusive. The estimates of the direct costs related to irritable bowel syndrome care ranged from Canadian$259 to US$619 annually, with charge data ranging from US$742 to US$2504 annually. The sub-group of patients with severe symptoms of irritable bowel syndrome required as much as US$1743 in direct costs per year. It was estimated that $1.3 billion are expended annually in direct costs associated with irritable bowel syndrome care in the USA, whereas a similar estimate in the UK was £45.6 million. Productivity cost estimates ranged from US$335 to Canadian$748 per patient annually, with total annual productivity losses for the USA estimated at $205 million. Total costs from a societal perspective, including both direct and productivity values, ranged from Canadian$1007 to US$2078 per patient per year, whilst the total annual expenditure in the USA was estimated to be $1.56 billion.

Although irritable bowel syndrome is not associated with significant mortality, the direct and productivity costs associated with the management of this disorder place it within the 10 most expensive gastrointestinal diseases in the USA.[10] It is likely that the presence of chronic symptoms without adequate treatment options in a non-fatal disorder actually increases the cost of management, as the absence of significant mortality acts to increase the prevalence of the disorder. A significant decrement in the health-related quality of life has been demonstrated in irritable bowel syndrome. A recent systematic review illustrated that the impact of irritable bowel syndrome was similar to that of gastro-oesophageal reflux disease or depression.[11] Whilst the severity of irritable bowel syndrome symptoms correlated with decrements in the perceived quality of life, respondents who met the criteria for irritable bowel syndrome but who had not sought health care reported a similar quality of life to non-irritable bowel syndrome controls.

It should be noted that the economic burden of irritable bowel syndrome is not limited to the USA. Even in countries in which a national health service provides care, the costs associated with irritable bowel syndrome are high.[25,26,30,33,34] Although it is difficult to directly compare health care costs across national borders due to differences in economic structure and currency, the studies evaluated in this review consistently illustrate that the magnitude of direct health care resource consumption and productivity losses that are sustained internationally as a result of this disorder is similar.

Five studies reported in this review compared health care utilization in subjects with symptoms of irritable bowel syndrome with that in populations without irritable bowel syndrome symptoms. In each report, direct health care costs were significantly higher amongst subjects with irritable bowel syndrome or irritable bowel syndrome symptoms than in control populations without irritable bowel syndrome symptoms.[24,28,29,32,33] In those studies evaluating the total costs of all health care in addition to irritable bowel syndrome-related expenditure, it was consistently noted that total health care resource utilization was greater amongst irritable bowel syndrome patients than in matched control patients without irritable bowel syndrome.

This study utilized an evidence-based approach to summarize the data regarding irritable bowel syndrome costs. Specifically, a systematic review was conducted using previously published methods.[22,23] In a systematic review, unlike conventional non-systematic reviews, bias is limited by establishing criteria for the performance of the literature search and for the inclusion of the studies in the review in an a priori manner. It should be noted that, although there were a large number of published studies on this topic, few met the pre-defined criteria for inclusion in this review.

There was great variation in the estimated costs of irritable bowel syndrome between the various studies. The reasons for this variation are multiple. The studies were performed in different countries, with different health care systems and different costs for the same services or products. The studies used different methodologies to ascertain costs. Different direct and indirect costs were included in the different studies. Different assumptions were made in the cost estimates. Different irritable bowel syndrome patient groups were included in the various studies, with many studies limited only to the small percentage of irritable bowel syndrome patients who seek care. Finally, different perspectives were used in the various studies. With the wide variation in study methodology and assumptions, it is not surprising to find a wide range of estimates for the costs of irritable bowel syndrome. The one common factor in all of the studies was the conclusion that irritable bowel syndrome is a disease that imposes large direct and indirect costs on the health care system and society. Although the exact costs are difficult to calculate, there is no doubt that the financial impact of this disease is extremely high.

Several other considerations should be made with regard to cost determination in irritable bowel syndrome. The lack of effective therapy has the effect of decreasing the estimated pharmaceutical component of direct health care costs. As opposed to gastro-oesophageal reflux disease, where drug costs are estimated to account for 63% of the total direct costs, only 6% of irritable bowel syndrome direct costs are attributed to medication.[10] On the other hand, 21% of the total direct costs of management of gastro-oesophageal reflux disease are consumed through hospital admissions, whereas 63% of irritable bowel syndrome-related direct costs are attributed to in-patient stays for evaluation, diagnosis and treatment.[10] A significant shift in costs may occur if effective therapy is made available, away from health care encounters or diagnostic tests and towards pharmaceuticals. It should also be recognized that many pharmaceutical therapies for irritable bowel syndrome are available over the counter, imposing costs on patients, but often not captured in estimates of third-party health care costs.

Further research to examine the economic burden of irritable bowel syndrome should focus on several aspects highlighted by this article. It would be ideal to perform the analysis from a societal perspective, so that not only direct health care costs, but also productivity (indirect) costs may be included, as the latter are especially critical when analysing a disease such as irritable bowel syndrome that is associated with more morbidity than mortality. Costs should be reported in a format that reflects the skewed distribution of costs amongst patients, which may include using median values, bootstrapping methods or other non-parametric forms of analysis. The source from which costs are derived should consist of a validated cost-accounting system or claims database. A control group without irritable bowel syndrome, with or without other gastrointestinal disorders, may be useful to more fully assess the economic impact of irritable bowel syndrome. Although irritable bowel syndrome patients exhibit a wide variation in symptom severity, comparison of resource expenditure stratified by this factor is lacking. Finally, total medical care costs, in addition to costs incurred for irritable bowel syndrome care, should be reported, as several studies have noted significantly higher total medical costs in patients with irritable bowel syndrome.

In summary, the economic impact of irritable bowel syndrome is substantially greater than its effect on mortality, illustrating that a disorder need not be lethal in order for tremendous health care resources to be expended in its management. The productivity losses incurred as a result of morbidity contribute in addition to direct health care costs, and the combined losses far exceed those incurred by non-irritable bowel syndrome patients. Geographical boundaries are spanned by this disorder and the impact on national health care in countries other than the USA accounts for considerable deficits. As therapeutic options at the present time are limited, productivity at work and leisure activities suffer, neither of which is quantifiable by present means. The development of effective therapy may dramatically shift resource use away from costly diagnostic evaluations, decrease the productivity (indirect) costs incurred by this disorder and improve the quality of life.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.

processing....