Irritable bowel syndrome: Toward a cost-effective management approach

Abstract

To examine the economic implications of current irritable bowel syndrome (IBS) management practices and formulate recommendations based on these implications.
Relevant English-language research publications in which the direct and indirect costs of IBS were examined, identified using a search of records contained in Medline.
Review of the identified publications indicates that in Western nations, IBS management is associated with high direct costs (particularly for diagnostic testing, office visits, pharmacotherapy, and emergency department visits). Indirect costs, associated with lost wages and decreased productivity, account for the largest proportion of the IBS economic burden. Moreover, rapid projected growth in IBS disease-related costs indicates a need for more focused attention toward improved treatment of IBS. More cost-effective management might be achieved by diagnosing and instituting nonpharmacologic and pharmacologic management earlier in the disease process. Under such an approach, patients are classified based on symptoms and a therapeutic trial is begun. More extensive, expensive diagnostic testing is reserved for patients refractory to treatment or for whom serious disease must be ruled out.
IBS is a condition with high direct and indirect costs. Management strategies should be evaluated both on their clinical efficacy and on their cost effectiveness. As new, IBS-specific pharmacotherapies become available, the ability to diagnose and manage the condition in a cost-effective manner can be improved.

Full text

S268 THE AMERICAN JOURNAL OF MANAGED CARE JULY 2001
Abstract
Objective: To examine the economic impli-
cations of current irritable bowel syndrome (IBS)
management practices and formulate recom-
mendations based on these implications.
Methods: Relevant English-language research
publications in which the direct and indirect
costs of IBS were examined, identified using a
search of records contained in Medline.
Results: Review of the identified publications
indicates that in Western nations, IBS manage-
ment is associated with high direct costs (partic-
ularly for diagnostic testing, office visits, pharma-
cotherapy, and emergency department visits).
Indirect costs, associated with lost wages and
decreased productivity, account for the largest
proportion of the IBS economic burden.
Moreover, rapid projected growth in IBS disease-
related costs indicates a need for more focused
attention toward improved treatment of IBS.
More cost-effective management might be
achieved by diagnosing and instituting nonphar-
macologic and pharmacologic management ear-
lier in the disease process. Under such an
approach, patients are classified based on symp-
toms and a therapeutic trial is begun. More
extensive, expensive diagnostic testing is
reserved for patients refractory to treatment or for
whom serious disease must be ruled out.
Conclusion: IBS is a condition with high
direct and indirect costs. Management strate-
gies should be evaluated both on their clinical
efficacy and on their cost effectiveness. As new,
IBS-specific pharmacotherapies become avail-
able, the ability to diagnose and manage the
condition in a cost-effective manner can be
improved.
(Am J Manag Care 2001;7:S268-S275)
Irritable bowel syndrome (IBS) is a
chronic and recurrent type of func-
tional gastrointestinal (GI) disorder.
Although IBS is the most common disor-
der diagnosed by gastroenterologists,1,2
many patients may not seek treatment,3
and the disease prevalence may be
underestimated. IBS has been a diffi-
cult disease to diagnose, and only
recently are therapies based on patho-
physiology becoming available. This
article reviews the economic and
health burden of IBS and makes rec-
ommendations for cost-effective man-
agement of the condition.
IBS: A Difficult Condition to Diagnose
Historically, the diagnosis of IBS has
been based on clinical patterns rather
than physical signs because the symp-
toms may not be linked with clear objec-
tive findings. The condition involves
changes in bowel patterns (either consti-
pation or diarrhea) and abdominal pain,
discomfort, and bloating.4,5 Despite such
recognizable symptoms, radiologic, endo-
scopic, and laboratory testing reveal no
significant structural or biochemical
abnormalities of the GI tract.5,6 This lack
of objective findings may occur because
Irritable Bowel Syndrome: Toward a
Cost-Effective Management Approach
Robert Martin, MS, RPh; John J. Barron, PharmD;
and Christopher Zacker, RPh, PhD
. . . REPORT . . .
Address correspondence to: Christopher Zacker,
RPh, PhD, Novartis Pharmaceuticals Corporation,
Health Care Management, 59 Route 10, East
Hanover, NJ 07936-1080; Tel: (908) 696-0664;
Fax: (908) 696-8840; E-mail: christopher.zacker
@pharma.novartis.com.

VOL. 7, NO. 8, SUP. THE AMERICAN JOURNAL OF MANAGED CARE S269
Irritable Bowel Syndrome:Toward a Cost-Effective Management Approach
the condition is not caused by structur-
al problems in organs of the GI system.
Recent research indicates that IBS
may be caused by dysfunction of neuro-
logic mechanism(s) that leads to alter-
ations in GI motility and visceral sensory
perception.6,7 For instance, scientists
have found that patients with IBS experi-
ence abdominal pain at significantly
lower distension volumes, respond at
lower than normal thresholds to various
painful gut stimuli, and have more fre-
quent high-amplitude contractions of
the rectosigmoid.8Several studies have
shown that IBS diagnosis is correlated
with other, non-GI somatic conditions,
including headache, fatigue, urologic
and gynecologic symptoms, fibromyal-
gia, and depression.9,10 Together, these
findings suggest that IBS may be associ-
ated with a systemic neural disorder.
Issues also arise about the characteris-
tics of the population that seeks medical
help for this condition. Based on US sur-
veys, IBS is the seventh most common
diagnosis encountered by all physicians,
and its symptoms are estimated to be
present in up to 20% of the population at
any one time.1,2 In Western countries,
IBS is reported by women 3 times more
often than by men,11 and women seek
medical care for IBS twice as often as
men.1However, cross-cultural differ-
ences in the female-to-male incidence
ratio suggest that this may reflect cultural
gender differences in healthcare-seeking
behavior.8Physicians attempting to diag-
nose IBS should have these patterns of
care-seeking behavior in mind and need
to be cognizant that some patients suffer-
ing from IBS may be hesitant to seek
treatment.
The Economic Challenge of IBS
Overall Cost Estimates. A communi-
ty-based study showed that annual socie-
tal costs associated with IBS are about
$8 billion (1992 $US).12 This estimate
adjusted to 1999 $US amounts to $10.5
billion annually. Further, even this esti-
mate may be low because this study did
not include prescription drug costs and
indirect costs related to lost wages, and
nonmedical costs such as home care.12,13
Indeed, IBS patients take over 2 million
prescriptions annually. Fullerton14 found
a wide range of estimates of the total
international costs of IBS, amounting to
about $41 billion ($US) in 8 major indus-
trialized countries.
Cost increases are a result of increas-
es in various aspects of medical care.
Eisen et al15 performed a cross-sectional,
case-controlled study of patients enrolled
in the Lovelace Healthcare management
organization. Over the course of 1 year,
IBS respondents at Lovelace Healthcare
filled more prescriptions (5.9 versus 4.8),
had a greater number of outpatient visits
(9.1 versus 6.9), and had higher outpa-
tient charges ($934 versus $680) than
patients without IBS (G. M. Eisen et al,
unpublished data, 2001).
Indirect Costs. Cost estimates for the
total economic burden associated with
IBS are likely to be lower than actual
costs because a clinical diagnosis of IBS
is often not made and the indirect costs
are not well characterized. In a survey of
5430 mailings from a random sample of
US households,16 people with IBS symp-
toms missed work or school an average of
13 days per year, an absenteeism rate
nearly 40% greater than among people
without these symptoms. IBS affects
many aspects of a patient’s life because
its symptoms disrupt sleep, diet, and
sexual functioning.17-19 These changes, in
turn, interfere with daily activities and
disrupt the ability to function in family
and work-related roles. Using the Short
Form-36 (SF-36), an extensively validat-
ed quality-of-life (QOL) instrument, in a
cross-sectional, point-in-time, postal
survey, Hahn et al20 showed that a ran-
dom sample of 1000 IBS patients from
both the United States and United
Kingdom experienced serious QOL
decrements compared with norms in all
dimensions of health measured. They
found that one third of the IBS patients
reported work absenteeism, with an
average of 1 to 2 workdays missed every
4 weeks.20

S270 THE AMERICAN JOURNAL OF MANAGED CARE JULY 2001
REPORT
Although indirect costs related to IBS
have received scant research attention,
several studies indicate they account for
the largest proportion of total annual IBS
costs. For instance, wages lost because of
IBS-related absenteeism in Canada dur-
ing 1999 were estimated to be slightly
over $1 billion.21 In a database study of
630 employees with IBS and 1260 with-
out any GI disorders, IBS patients were
found to have 3.27 more absences annu-
ally than those with no GI conditions
(A. J. Chawla, PhD, et al, unpublished
data, 2001). Based on expected demo-
graphic and economic changes, total
indirect costs of functional digestive dis-
eases (including functional dyspepsia
and IBS) in the United States were pro-
jected to grow to $19.6 billion in 2000.14
Diagnostic Testing: Substantial Portion
of Disease Cost. Because of the absence
of an objective, confirmatory test for
IBS, physicians are advised to base
diagnosis on the recognition of changes
in bowel patterns and pain/bloating
(Tables 1, 2).4,22,23 Because symptoms
are not specific to IBS and in some
cases may signify more serious disease
(eg, malabsorption, inflammatory bowel
disease, cancer), diagnosis based on
symptoms alone is unlikely to be accu-
rate or prudent.22 Alarming symptoms,
such as nocturnal awakening with onset
of symptoms and the passage of mucus
or blood with defecation, need to be
more aggressively evaluated.6Physicians
are advised to conduct a limited num-
ber of diagnostic procedures that rule
out structural and biochemical abnor-
malities. These are to be chosen based
on the patient’s age, symptom severity
and duration, and medical and family
history.10,24,25
A considerable portion of IBS costs
may be attributable to diagnostic investi-
gations.21 Studies suggest that IBS con-
tinues to be overinvestigated.26 For
example, in a recent Canadian study,
diagnostic tests for IBS accounted for
$41 million and $59.7 million (1996
Canadian dollars) in Ontario and
Quebec, respectively. In both provinces,
this consumed the largest proportion of
the total annual IBS direct costs (45% to
46%), exceeding the proportion expend-
ed for drugs (up to 19%), office visits (up
to 29%), or emergency department visits
(up to 11%).21 Similarly, in the United
States, estimated annual costs for labora-
tory and radiologic investigations are
higher among IBS patients (US $196)
than among patients with other, non-GI
symptoms (US $114) and accounted for
26% of the annual direct costs observed
among the IBS patients studied.12 In the
United Kingdom, a recent study showed
that 63% of IBS patients underwent an
investigative procedure, such as barium
meals or enemas, small bowel X rays,
abdominal ultrasound, and occult blood
testing.27 Camilleri and Williams26 fur-
ther stated that high diagnostic costs for
IBS in the United States may be the
result of a system that creates incen-
tives for overinvestigation because of
Table 1. Manning Symptoms of IBS
IBS = irritable bowel syndrome.
*Significantly more common in patients with IBS
(P< .001).
†Significantly more common in patients with IBS
(P< .01).
Source: Manning AP, Thompson WG, Heaton KW,
Morris AF. Towards positive diagnosis of the irritable
bowel. BMJ 1978;2:653-654. Adapted with permission.
■Looser stools with onset of pain*
■More frequent stools with onset of pain†
■Pain relief after bowel movement†
■Visible distension†
■Sensation of distension
■Passage of mucus
■Sensation of incomplete emptying
■Bowel movement before breakfast
■Nocturnal bowel movement
■Urgency of defecation
■Pain worsening after bowel movement
■Pain eased with flatus
■Two bowel movements between meals
■Harder stools with onset of pain
■Less frequent stools at onset of pain

VOL. 7, NO. 8, SUP. THE AMERICAN JOURNAL OF MANAGED CARE S271
Irritable Bowel Syndrome:Toward a Cost-Effective Management Approach
reimbursement for individual diagnostic
procedures.
Is all of this diagnostic intensity
required? US, UK, and Danish studies
show that initial misdiagnosis is rare,28-30
and additional testing, in the absence of a
change in the nature of symptoms, sel-
dom alters the initial diagnosis.10,31
Together, these studies suggest that cur-
rent diagnostic practices for IBS are not
cost effective and present opportunities
for cost reduction through the use of
more standardized diagnostic guidelines.
Recently, Suleiman and Sonnenberg32
found that inexpensive and noninvasive
tests (history plus physical examination,
laboratory test panel, hydrogen breath
test, and small bowel follow-through) of
IBS provided a diagnostic probability over
80% at a cost of $398. Use of flexible sig-
moidoscopy or colonoscopy increased the
diagnostic probability to a small extent
but increased costs substantially.
Physician Office Visits
Patients with IBS visit physicians’
offices about 3.5 million times per year.11
IBS patients in both the United States
and the United Kingdom have frequent
office visits, with 1 study indicating an
average of 4.7 and 5.2 visits per year,
respectively.20 These and other studies
indicate that such office visit rates are
much higher than those seen for patients
without IBS.12,16,20,33 Moreover, IBS
patients report a higher number of office
visits for non-GI symptoms.16 In their
large community survey, Talley et al12
found that costs for office visits (US
$228) may account for 31% of the total
annual cost incurred per IBS patient.
Studies conducted in the United
Kingdom and Canada report similar esti-
mates.13,21 For instance, Bentkover et al21
found that in Ontario, Canada, 29% of
the direct costs incurred by IBS patients
were attributable to office visits to gen-
eral practitioners, though a lower figure
(18%) was seen in Quebec.21 These find-
ings are in line with an earlier analysis
from Wells et al,13 who estimated that
visits to a general practitioner were
responsible for 29% of the total estimat-
ed direct costs incurred by IBS patients
in the United Kingdom in 1995.
However, to the best of our knowledge,
the earlier Wells study did not include
charges for visits to specialists. This may
be critical to accurately estimating
office-visit costs. The recent Bentkover
study indicated that visits to specialists
were responsible for an additional 10% of
resource usage.21
Prescription Drug Costs. Because the
underlying cause of IBS is not known,
treatment focuses on symptom manage-
ment. Although dietary and behavioral
modifications are suggested,7clinical tri-
als have failed to show the efficacy of
these approaches, and most patients
who receive therapy are managed with
prescription drugs. Seventy-five percent
of visits to gastroenterologists for IBS
symptoms result in GI drug prescrip-
tions,1and over 2 million prescriptions
are received for IBS management annu-
ally.11 Commonly prescribed drugs for
IBS include antidiarrheals, antispasmod-
ics, cathartics/laxatives, acid reducers,
analgesics, and antidepressants.8In a
claims-based review of drug utilization
data from 3149 patients diagnosed with
Table 2. Rome II Criteria for IBS Diagnosis
IBS = irritable bowel syndrome.
Source: Reference 5.
At least 12 weeks, which need not be consecutive, in the preceding
12 months of:
Abdominal pain or discomfort
that has 2 of 3 features:
■Relieved with defecation, and/or
■Onset associated with change in frequency of stool, and/or
■Onset associated with change in form (appearance) of stool
Supporting symptoms
■Abnormal stool frequency (>3/day or <3/week)
■Abnormal stool form (lumpy/hard or loose/watery)
■Abnormal stool passage (straining, urgency, or feeling of incomplete
evacuation)
■Bloating or feeling of abdominal distension

S272 THE AMERICAN JOURNAL OF MANAGED CARE JULY 2001
REPORT
IBS, it was found that antispasmodics
were the most commonly prescribed
medication for IBS (51%).34 The majority
of IBS patients receive 2 or more drugs,
either singly or concurrently, during the
year after IBS diagnosis,34 which may
indicate a need for more effective
monotherapies that can impact the mul-
titude of symptoms exhibited by IBS
patients. Few studies have examined the
prescription drug cost component in IBS
sufferers. In Canadian and UK studies,
costs associated with IBS prescription
drug use were estimated to account for
between 5% and 27% of the total annual
cost of caring for IBS patients who seek
medical care.13,21
Inpatient/Emergency Department
Services. A number of studies indicate
that IBS patients are more likely to
receive emergency or inpatient medical
care and to incur higher expenditures
related to such care than people with
non-GI symptoms.12 IBS patients in
the United Kingdom and in the United
States who reported receiving some form
of medical assistance presented for emer-
gency care an average of 1.5 and 1.8
times per year, respectively.20 In the large
US study by Talley et al,12 17% of such
IBS patients received emergency and/or
inpatient care with a median cost (1992
$US) of $1024. This was nearly twice the
proportion of patients with non-GI symp-
toms who received such care (9%), and
the median cost per visit was nearly
twice that for controls.12 In the Canadian
study by Bentkover et al,21 analysis of
emergency department usage revealed
a similar trend: 7% and 9% of IBS
patients in Quebec and Ontario, respec-
tively, were judged to be in need of
emergency department services, and
these services constitute a considerable
portion (7% to 11%) of the total estimat-
ed costs of IBS management in these
provinces. According to 1 study, com-
pared with charges for non-GI patients,
higher hospital costs for IBS patients
may be attributed not only to more fre-
quent emergency department visits but
also to the higher probability of under-
going a variety of abdominal and
extra-abdominal surgeries, including
gynecologic and urologic procedures,
as well as removal of skin lesions, eye
or nasal surgery, and breast biopsies.35
Summary of Cost Analysis
IBS patients are 1.6 times more like-
ly to present for medical care than sim-
ilar patients without such symptoms,12
and costs incurred are higher for
patients with IBS than for people with
non-GI symptoms who present for med-
ical care. Excess costs have been
reported in every category examined,
including investigational procedures,
physician office visits, outpatient hospi-
tal costs, emergency and inpatient hos-
pital charges, and indirect costs as a
result of lost wages and decreased qual-
ity of life. The average annual direct
cost per IBS patient has been estimated
to be 58% higher than that seen with a
demographically similar patient without
IBS.12 Collectively, these studies suggest
that IBS presents significant economic
burdens to both the healthcare industry
and society as a whole.
Recommendations for Cost-Effective
Management
The economic burden of IBS is heavy
and continues to grow,14 making devel-
opment of effective and cost-sparing
management guidelines ever more
important in the absence of a curative
treatment. As has been documented in
other types of chronic diseases, the pat-
tern of frequent office visits, repeated
investigative procedures, and utilization
of multiple prescription and nonpre-
scription drugs12,27,34 indicates that IBS
patients appear to suffer substantial
symptoms and decreased quality of life.
Many of the therapies currently used
for IBS only target 1 symptom and are
ineffective or produce adverse effects.
Limited success with these agents may
frustrate physicians and patients.
Difficulties in diagnosing the condition
and dissatisfactory therapies may lead
patients to “doctor shop” in an attempt
to achieve relief from IBS symptoms.

VOL. 7, NO. 8, SUP. THE AMERICAN JOURNAL OF MANAGED CARE S273
Irritable Bowel Syndrome:Toward a Cost-Effective Management Approach
Detailed cost analyses and disease
burden studies highlight clear opportu-
nities for improving the diagnosis and
management of IBS. In particular, inves-
tigators have attempted to target more
efficient and effective approaches that
reduce resource utilization for investiga-
tive procedures, frequent office visits,
and specialist referrals. With these goals
in mind, a number of authors have pro-
posed strategies and helpful guidelines
(Table 3) aimed at primary care physi-
cians, who manage the majority of IBS
patients.27
For instance, to avoid unnecessary,
expensive, repeated, and sometimes
risky investigations, physicians manag-
ing patients with suspected IBS (based on
clinical features, a thorough patient and
family history, and limited, complemen-
tary investigation) may initiate appro-
priate symptomatic treatment, with
reassessment in several weeks.7,24,36 Most
of the tests recommended for initial diag-
nosis of patients with mild or moderate
IBS symptoms, such as blood tests and
stool tests, are available to the primary
care provider.37 For many patients, this
appears to be a prudent, low-risk, and
cost-effective approach.
The currently recommended diagnos-
tic screening procedures include but are
not limited to selected laboratory tests of
blood and stool samples, colonoscopy,
endoscopy, proctosigmoidoscopy, biopsy,
radiographic testing, GI motility studies,
and ultrasound.8,10 In the systematic
approach, patients meeting initial diag-
nostic criteria undergo a limited screen
for organic disease. They are then catego-
rized based on symptoms (diarrhea, con-
stipation, gas/bloating/pain) and are then
treated. Only when the symptoms are
intractable are further expensive diagnos-
tic tests required. Suleiman and
Sonnenberg32 suggest that use of flexible
sigmoidoscopy and colonoscopy should
be reserved for cases in which serious
organic disease is suspected and must be
ruled out.
The management of IBS has been
limited because the available IBS med-
ications are nonspecific. Recently,
agents have been developed that specif-
ically target IBS. Tegaserod, a partial
5-hydroxytryptamine agonist, has been
found effective for accelerating oroce-
cal transit time in female IBS patients
with constipation.38 Tegaserod has
been shown to reduce abdominal pain,
bloating, and constipation. It also
improves bowel consistency.39 The
agent, alosetron, which was approved
by the Food and Drug Administration
(FDA) for female IBS patients whose
predominant bowel symptom is diar-
rhea,40 was recently withdrawn from
the market because of safety concerns.
(An FDA advisory committee meeting is
planned to consider reintroducing the
drug as a treatment for IBS.) Other
agents under investigation include
kappa-opioid antagonists and neu-
rokinin antagonists.39 Clinicians should
consider new IBS-specific therapies as
they become available as they may pro-
vide more effective management.
Regardless of which therapy is consid-
ered, primary care providers should
proactively educate patients about the
nature of IBS.8,29 The physician who con-
fidently reaches a diagnosis, provides
reassurance about the non–life-threaten-
ing nature of IBS, and discusses the
Table 3. Primary Care Strategies for Reducing Direct and
Indirect IBS Expenditures
IBS = irritable bowel syndrome.
■Diagnose IBS based on positive symptom criteria (eg, Rome,
Manning) and limited investigation
■Initiate early trial of symptomatic treatment (3 to 6 weeks)
■Establish a positive, strong physician-patient relationship
Educate
Reassure
Discuss precipitating factors
Obtain and discuss psychosocial history
■Discuss and negotiate treatment
■Conduct further investigations only if symptoms are intractable
■Discourage repeated investigations
■Refer to specialist if symptoms are severe
■Communicate and coordinate care with specialist

S274 THE AMERICAN JOURNAL OF MANAGED CARE JULY 2001
REPORT
recurrent and often chronic nature of
the syndrome confers several impor-
tant benefits to the patient. The physi-
cian should emphasize that there is no
cure for the condition, but it can be
treated. Patients who are satisfied and
confident with the physician’s diag-
nosis are less likely to require referral
to a specialist.23 Moreover, explaining
to the patient that his/her symptoms
are not life-threatening but are likely
to be recurrent provides necessary
reassurance while laying a foundation
for realistic patient expectations.
Importantly, reassurance and educa-
tion are likely to reduce the possibility
of referral or “doctor shopping” as well
as patient requests for additional,
unnecessary investigations.23 The
patients should also be counseled
about the various treatment options.
The informed patient may experience
less stress and fear, which may in turn
alleviate symptoms and help the
patient better cope with symptoms and
maintain a higher quality of life.
Promoting and maintaining patient
compliance would also lead to benefi-
cial outcomes. Further, these common-
sense steps play an important role in
establishing a positive physician-
patient relationship and have been
shown to result in fewer return visits for
IBS-related symptoms, suggestive of a
more positive patient outcome.29
Primary care physicians are also
encouraged to establish good communi-
cation with the specialists to whom they
refer IBS patients with severe symptoms.
Such communication can prevent
duplication of tests as well as provide
support to the primary care physician,
who is likely to continue to manage the
majority of a given IBS patient’s health-
care needs.23
The search for more effective treat-
ments for IBS holds more promise today
than in the past. Until safe therapies
become available, providers can take
immediate and simple approaches to
help improve outcomes and reduce costs
associated with diagnosis and long-term
IBS symptom management.
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