Supplements and Featured Publications
Economic Impact of Irritable Bowel Syndrome: What Does the Future Hold?
Volume 11
Issue 1 Suppl

Total Costs of IBS: Employer and Managed Care Perspective

Irritable bowel syndrome (IBS) is a common gastrointestinalmotility disorder that typically affectspersons of working age and is costly to employers.The financial burden attributable to the direct (use ofhealthcare resources) and indirect (missed days fromwork [absenteeism] and loss of productivity while atwork [presenteeism]) costs of IBS is similar to that ofother common long-term medical disorders, such asasthma, migraine, hypertension, and congestiveheart failure. The symptoms of IBS are significantlybothersome and place a substantial burden on thepersonal and working lives of patients. As with otherlong-term medical conditions that have a significantimpact on productivity, directed efforts by employerscan address IBS in the workplace and therebypotentially decrease its impact. In this article, thesymptoms of IBS and its impact on patients and onsociety as a whole are discussed; options are outlinedby which employers can help reduce the totalcosts of IBS, including lost productivity (both absenteeismand presenteeism), in the workplace.

(Am J Manag Care. 2005;11:S7-


Irritable bowel syndrome (IBS) is a commongastrointestinal (GI) motility disorder,characterized by abdominal painor discomfort and altered bowel function,that has been estimated to affect up to 10%to 15% of North Americans.1 IBS can affectpersons of all ages, but it is most often diagnosedin working-aged persons, typicallythose between the ages of 30 and 50 years.2Although IBS is estimated to affect millions,only 25% of persons with IBS actually seekmedical treatment for their symptoms.3

Partly because of its chronicity, manypatients with IBS experience symptoms foryears before they seek medical attention.4,5For example, 42% of respondents to the IBSin the Real World Survey reported that theyhad IBS symptoms for an average of 10 yearsbefore diagnosis.5 Similar results wereobtained from the IBS Bulletin Survey, inwhich 50% of respondents reported that theyhad IBS symptoms for 11 years or longer.4

Given its prevalence and epidemiology, itis not surprising that IBS has the potential toimpose a substantial financial burden onsociety.6-8 IBS has been shown to be associatedwith significant direct (use of healthcareresources) and indirect (absenteeism[missed days of work] and presenteeism[loss of productivity while at work]) costs. Infact, indirect costs appear to account formost of the financial burden associatedwith IBS.9,10

Recently, interest in the relationshipbetween this burden and employers hasgrown—perhaps, in part, because of theavailability of newer agents for treatment—and substantial employer costs have beenidentified.11 Because IBS remains a poorlyrecognized and understood condition, formallyaddressing IBS in the workplace andeducating employers and employees aboutthe disorder may reduce the burden of IBSby improving the delivery of effective therapiesto employees with IBS.

Total Costs of IBS

Total costs attributable to any medicalcondition are composed of direct (ie, physicianvisits, outpatient care, inpatient/emergencycare, diagnostic tests) and indirect (ie,lost worker productivity—both absenteeismand presenteeism) costs.

Previously, the socioeconomic impact ofIBS on the workforce was difficult to measureobjectively—researchers had to rely onobservations of crude absenteeism rates.Several studies have demonstrated thatthese rates are significantly higher for IBSpatients than for matched controls.12,13 Forexample, a survey of 5430 persons from arandom sample of US households found thatillness caused the average patient with IBSto miss 13.4 days per year from work orschool, whereas the average subject withouta GI disorder missed only 4.9 days per yearbecause of illness.12 In another survey ofidentified IBS patients in the United States(n = 287), 30% of respondents reported thatthey had missed work completely because oftheir IBS symptoms, and 46% reported thattheir symptoms had forced them to leaveearly or to report late for work.13

Direct costs attributable to IBS have beenestimated to be approximately $1.5 billion6,14,15;however, based on an estimate of$8 billion in 1992, one report estimated theadjusted direct costs to be as high as $10 billion,excluding the costs of prescription andover-the-counter (OTC) drugs. In addition,the indirect costs of IBS, which are largelyborne by the employer, have been estimatedto be as high as $20 billion.6 However,given that this estimate is based on costsassociated with IBS patients who soughtmedical attention—only a minority ofpatients with IBS—unmeasured indirectcosts may be significantly higher than currentbest estimates.

For perspective, the prevalence of IBS1,8appears to be similar to that of other long-termconditions, such as asthma,16 coronaryheart disease (CHD),16 diabetes,16 hypertension,16 and migraine16 (Figure 1). However,the estimated total cost of IBS6,7 is greaterthan that of asthma17 or migraine18 (long-term,episodic conditions) and comparablewith that of hypertension19 and congestiveheart failure19 (long-term, persistent conditions)(Figure 2).

Direct Costs of IBS

Healthcare Utilization.

IBS is commonlydiagnosed by primary care physicians andgastroenterologists2,20; patients with IBSconstitute one of the largest diagnosticgroups in the gastroenterology setting.20,21According to the American GastroenterologicalAssociation, patients with IBS made3.65 million visits to physicians in 1998.6

Many consultations result in interventions,such as diagnostic tests and prescriptions.According to the 1997 NationalAmbulatory Medical Care Survey, medicationsfor the treatment of IBS symptomswere prescribed at an estimated 2.5 millionvisits per year, and 89% of IBS-related consultationsin 1997 resulted in at least 1 IBS-relatedprescription.22 This considerable useof healthcare resources has resulted in highcosts to managed care, patients, andemployers.

Costs to Managed Care.

Patients withIBS make a significantly greater number ofhealthcare visits per year than populationcontrols.23-25 This substantial use of healthcareresources results in considerable managedcare costs. For example, analyses of useand cost data obtained through the computerizedinformation systems of a large, staff-modelhealth maintenance organization(HMO) in western Washington demonstratedthat the total costs of all healthcare providedby the HMO during a 12-month periodwere slightly more than $4000 for patientswith IBS (n = 3153) compared with approximately$2700 for population controls (a49% difference).26

Costs to Patients.

A commonly overlookedcomponent of the total cost of IBS isthe time and cost expenditure for individualpatients with IBS. Many patients reportsubstantial out-of-pocket expenses for IBStherapies.27 For example, a recent survey of657 members of the Intestinal DiseaseFoundation found that patients with IBSspent an average of $288 on OTC and alternativetherapies for their IBS symptoms duringthe 3 months preceding the survey.27

Costs to Employers.


Although IBSimposes a significant financial burden onpatients and managed care, employersshoulder a large proportion of the totalcosts—both direct costs (insurance payments)and indirect costs (absenteeism andpresenteeism)—attributable to IBS. Regardingdirect costs, a recently published surveyof beneficiaries with IBS (n = 1509; subset ofemployees, n = 504) who were identifiedfrom administrative claims data of a nationalFortune 100 manufacturing companyfound that employees with IBS cost thisemployer 1.5 times more than employees ina matched control sample ($6364 [employeeswith IBS] compared with $4245 [controls];< .001; Figure 3),11 resulting in anestimated $1.9 million per year in additionalcosts to the employer. Presumably, this isan underestimation—because this studyanalyzed claims data, indirect costs includedonly absenteeism costs; adding presenteeismcosts would probably have increasedthe total cost estimate substantially. Of note,the most significant incremental costs to theemployer in this analysis were related to thegreater use of ambulatory care and prescriptiondrugs by IBS patients than by controls.IBS did not appear to result in high levels ofdisability, nor did it cause substantial use ofinpatient care11—which employers typicallyequate with high cost—most likely becausethis condition waxes and wanes.

Indirect Costs of IBS

Although direct costs are more easilyquantified and tracked, long-term andepisodic conditions, such as IBS, also resultin substantial indirect costs. In fact, it is estimatedthat direct costs account for less thanhalf the total costs of IBS that employersincur.9 Disease-related indirect costs,including absenteeism from work, disabilityprogram use, worker compensation programcosts, worker turnover, family medicalleave, and presenteeism, account for most ofthe financial burden for employers.9

Productivity Costs.

The effects on workerproductivity caused by the symptoms andtreatment of several long-term (ie, diabetes,asthma, hypertension, heart disease, mooddisorders)28 and acute (ie, influenza)29 conditionshave been documented. The Table,30-38which shows baseline Work Productivity andActivity Impairment (WPAI) scores for severalcommon long-term and episodic conditions,illustrates this point. WPAI is aproductivity questionnaire that was developed as a general health measure and hasbeen modified and validated for specifichealth conditions, including IBS.10 It isdesigned to measure work impairment attributedto absenteeism (missed days fromwork) and presenteeism (reduced productivityat work) and impairment in daily activities,such as housework, shopping, childcare, and exercising.10 WPAI outcomes areexpressed as impairment percentages, withhigher numbers indicating greater impairmentand less productivity (ie, worse outcomes).Another measure of lost productivity,the work productivity score, enumeratesreduced productivity attributed to IBS symptomsas a percentage of potential total workproductivity during a full-time workweek.

Indirect costs associated with absenteeismand presenteeism as a result of IBSare substantial. In 1992, IBS was the secondleading cause, behind the common cold, ofworkplace absenteeism,39 and recent datasuggest that the gap may be shrinking.40-42 Ina study of 2143 patients with IBS identifiedfrom 47 074 telephone screening interviewsin the United States and in 8 Europeancountries (United Kingdom, Netherlands,Italy, Switzerland, Germany, Belgium,Spain, and France), Europeans with IBSreported missing an average of 4 to 10.9 daysof work during the previous year comparedwith 1.5 to 5.6 days reported by control subjects;Americans with IBS reported missing,on average, 6.4 days compared with 3 daysreported by matched controls.41 These findingsare consistent with previous surveys,which indicate that patients with IBS missmore than 6 days of work per year becauseof their symptoms.42 By way of comparison,a recent analysis concluded that affectedworkers lost roughly 1 day of work (9 hours)per common cold episode.43 Another surveyfound that 67% of adults experience atleast 1 cold per year and that among thoseadults the average is 2.2 cold episodes peryear.44

In addition to absenteeism, IBS symptomsare responsible for significant presenteeism.In fact, because IBS symptoms wax andwane, presenteeism actually results ingreater costs for employers than absenteeism.10 Patients with IBS tend to misswork sporadically rather than for longstretches of time.11 A 2-part survey of theemployees of Comerica Incorporated (N =11 806)—a nationwide bank with majorbranches in Michigan, California, Texas,and Florida—examined worker productivity(both absenteeism and presenteeism) usingthe WPAI. Results showed a reduced workproductivity rate of 21.1% among employeeswith IBS, which is equivalent to workingonly 4 days of a 5-day workweek.10 Anotherstudy surveyed members of a managed careorganization who had IBS (n = 574) andfound that the average indirect costsincurred for productivity losses caused bythe restriction of normal activities (ie, presenteeism)was $2837 per year amongemployed respondents (n = 151). Averagecosts resulting from absenteeism were estimatedto be $996 per year.45 These dataclearly indicate that IBS symptoms result in asignificant loss of productivity.

Impact on Patients.

Patients with IBSoften tolerate the symptoms for years beforethey seek diagnosis.4,5 IBS symptoms restrictor otherwise negatively impact manyaspects of patients'lives, including diet, travel,sleep, intimacy, and leisure activities.4,5,13,42,46,47 It has been demonstrated thatthe quality of life of IBS patients is substantiallydiminished compared not only withthe general population but also with patientswho have gastroesophageal reflux disease,asthma, diabetes, or migraine.48,49 Patientswith IBS report that symptoms often causethem to be late for work or to leave workearly.5,46,50 Because of their IBS symptoms,many have made job decisions they wouldnot otherwise have made, such as cuttingback on days of work, working fewer hours,turning down promotions or advancements,and working from home.4,5,13,42,46

Because of the nature of IBS symptomsand the fact that some employers do notaccept these symptoms as valid reasons forwork absence, patients often do not disclosethat they have IBS. For example, in the IBSBulletin Survey, 47% of respondents reportedthat they had not informed their employersof their IBS.4

All of these factors contribute to the complexityof managing IBS and have importantramifications for the implementation of IBSeducational programs in the workplace.Developing and implementing an appropriateprogram for IBS awareness, similar tothat for other long-term medical disorders,requires that employers be cognizant of thepotential presence and scope of the problemin their workforces and that they understandthe specific issues surrounding thediagnosis and treatment of this prevalentand costly disorder.

IBS in the Workplace—Steps forDeveloping an IBS Program

Despite the absence of biochemical orstructural markers for IBS, a positive diagnosisof IBS can be confidently made when astepwise, symptom-based approach is followed.1 A recent systematic review50 suggeststhat in the absence of "red flags"(Figure 4), which may be indicative oforganic GI disease, routine diagnostic testsare not required or even particularly discriminatoryfor making a positive anddurable diagnosis of IBS.50,51 These findingscorroborate those of an early study byHamm and colleagues.51 However, early andaccurate diagnosis is essential for the cost-effectivemanagement of IBS. The diagnosisof IBS is often delayed, causing patients toconsult multiple physicians, make multipleoffice visits, and undergo unnecessary andoften repetitive diagnostic testing and procedures,including, in some cases, unnecessaryabdominal surgeries.5,52,53

Effective therapies that are well toleratedand treat the multiple symptoms of IBS arealso essential to cost-effective management.54 Many patients are dissatisfied withtraditional IBS therapies such as fiber, antispasmodics,antidiarrheals, and laxatives,which typically address only individual IBSsymptoms (eg, constipation, diarrhea,bloating, or abdominal pain) and oftenswitch medications or use multiple medicationsto alleviate all of their IBS symptoms.55 Additional effective, well-toleratedagents that provide global relief of the multiplesymptoms of IBS could help diminishthe use of polypharmacy and thus reducethe total costs of prescription and OTCmedications.

Preliminary evidence suggests that theuse of novel IBS therapies, such as the serotonergicagent alosetron, a serotonin (5-HT)type 3 (5-HT3) receptor antagonist indicatedfor the treatment of women with severe IBSwith diarrhea, and tegaserod, a 5-HT4 receptoragonist indicated for use in women withIBS with constipation (IBS-C), may helpdecrease worker absenteeism and improveworker productivity. Tegaserod has alsobeen shown to be cost-effective.56 An economicmodel of the indirect costs associatedwith IBS and their reduction with treatmentintervention found that in the base case scenarioof employees with IBS-C, tegaserodtherapy results in an annual cost savings of$1882 in avoided lost productivity per treatedfemale employee with IBS.57 In addition,in a randomized, double-blind, placebo-controlled,multicenter study of 2600 womenwith IBS-C, tegaserod treatment was foundto significantly reduce work productivityand daily activity impairment.58

In addition to these therapeutic advances,innovative tools are now availablefor use in workplace educational awarenessprograms designed to help employees bettermanage their IBS symptoms.59 Such interventionshold promise for significantlydecreasing the impact of this condition inthe workplace.

Step 1: Implement an IBS Educational

Awareness Campaign.

An educationalawareness campaign in the workplace wouldhelp address the need for awareness aboutthe causes and consequences of IBS. IBS isassociated with numerous misconceptionson the part of employers, physicians, andpatients. For example, many patients withIBS fear that their IBS could progress to amore serious disease, such as cancer.60Others believe that their symptoms arecaused by lifestyle factors or that they arepsychosomatic.46

Many patients with IBS believe they haveinsufficient information about their disorder.60 When respondents in a recent telephonesurvey conducted in the UnitedStates were asked to select from a list oflong-term disorders that included asthma,depression, CHD, and diabetes, almost 50%ranked IBS as the medical disorder aboutwhich they knew the least.61 Similar resultswere found in Europe.60

Evidence also suggests that healthcareproviders should acquire a greater understandingof IBS. A study involving 36 generalpractitioners and 3111 patients in theUnited Kingdom found that IBS was identifiedin only 58% of patients whose symptomswarranted the diagnosis.62 Even physicianswho recognize and treat IBS seem unawareof the degree to which IBS disrupts anddebilitates affected patients. When describingon a scale of 1 ("barely noticeable") to10 ("completely incapacitating") the painassociated with IBS, IBS patients, on average,rated their pain as 6.3, whereas physiciansrated it as 5.163; these results indicatethat there is a disconnection between physiciansand patients regarding IBS.

Although these observations from theworkplace appear bleak, an IBS educationalawareness campaign may prove to be aneffective intervention. It has been welldemonstrated that workplace healthimprovement programs are effective in managingother long-term conditions.64 Patientswho have participated in these programsreport that they feel healthier and more incontrol of their disease; this outcome hasresulted in measurable reductions in medicalcare costs and absenteeism and inenhanced productivity in patients withdepression and diabetes.64-66

Step 2: Implement Incentive Programs.

Employers may consider implementingincentive programs to encourage employeeswith IBS to seek and comply with treatment.For example, the educational campaignand incentives program fordepression management initiated by FirstChicago Corporation in the 1980s resultedin reduced behavioral healthcare costs ineach subsequent year after its inception,and, by 1996, the mental health share oftotal healthcare costs had decreased from14% to less than 5%.64

It can be seen from the previous discussionthat on-site educational or incentiveprograms can help employees better managelong-term medical disorders and be moreproductive at work and that employers whoprovide such programs can reduce totaldirect healthcare costs and costs resultingfrom absenteeism and presenteeism.

Step 3: Reevaluate and Monitor

Program Impact.

Effective programs requirereevaluation and monitoring. Reevaluationallows for program updates and forthe introduction of new information, such asdetails about newly available therapies. Forexample, whereas sumatriptan was once thecost-effective choice for migraine management,67-69 the cost/benefit model shiftedwhen almotriptan was introduced to themarket. Almotriptan was found to be aseffective and as well tolerated as sumatriptan, but its acquisition cost was lower, makingit the more cost-effective choice.70 Forthem to be most effective, educational programsmust be kept current with new developmentsin disease management, andtreatment recommendations should be continuallymonitored to ensure that they staycurrent and relevant.


IBS is a long-term, episodic GI motilitydisorder that is prevalent among adults ofworking age. It imposes a substantial burdenon patients and employers. Although IBScan be confidently diagnosed on the basis ofcharacteristic symptoms, it is often misdiagnosedor underrecognized by patients andphysicians, leading to multiple physicianvisits, multiple medications, and unnecessarydiagnostic tests, procedures, and surgeries—all of which contribute to higherdirect medical costs. Additionally, employersincur significant costs because of IBS-relatedabsenteeism and presenteeism. Suchcosts have traditionally been difficult toquantify, but recent efforts have led to betterunderstanding of their magnitude. Educationalawareness programs have been usedsuccessfully to reduce the costs associatedwith other long-term disorders; with appropriateimplementation, such programs mighthave similar results for IBS. Finally, ongoingand future development of therapies thateffectively and safely provide global relief ofthe multiple symptoms of IBS may also helpto reduce the sizable costs associated withthis common condition.

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