The quality of life in patients with Crohn's disease

The quality of life in patients with Crohn’s disease

R. D. COHEN

University of Chicago Medical Center, Chicago, IL, USA

Accepted for publication 10 May 2002

SUMMARY

Background: Health-related quality of life studies provide

insight into the influence of Crohn’s disease on patients’

lives, and the potential impact on professional and

personal productivity.

Aim: To compare health-related quality of life in Crohn’s

disease patients with that in other patients and healthy

controls, and between medically and surgically treated

Crohn’s disease patients, and to correlate health-related

quality of life with Crohn’s disease activity.

Methods: An expanded MEDLINE search of full length,

English language, adult Crohn’s disease studies from

January 1966 to September 2000 was performed. The

key words utilized were: �Quality of Life�, �Health Status�or �Health Related Quality of Life� and �Crohn�s’ or

�Inflammatory Bowel Disease�.

Results: A total of 258 articles were identified; 236

subsequently were excluded, leaving 22 for analysis.

Compared with Crohn’s disease patients, the health-

related quality of life was better in healthy controls and

in ulcerative colitis patients (except pre-colectomy), but

similar to or worse than that in many other medical

conditions. The health-related quality of life was directly

correlated with Crohn’s disease activity, and was worse

in active disease than in remission. The health-related

quality of life was improved only in the short term in

surgically vs. medically treated Crohn’s disease patients.

Conclusions: Health-related quality of life analysis pro-

vides important insights into the impact of Crohn’s

disease, and should be included in clinical trials.

Researchers, clinicians and other health care providers

need to be cognizant of the impact of the health-related

quality of life upon patients’ lives.

INTRODUCTION

Crohn’s disease is a chronic, relapsing inflammatory

disease of the gastrointestinal tract. Rarely fatal, its

young age of onset and the morbidity associated with

the disease and its therapies have the potential to

profoundly affect patients, not only physically, but

also through limitations in social, educational, profes-

sional and emotional activities. The impact of Crohn’s

disease upon these factors can be quantified using

formalized studies of the health-related quality of life

(HRQOL).

The HRQOL has perhaps been most eloquently

described by Guyatt et al. as �the rubric for all those

things one might want to measure in clinical trials

beyond the traditional outcomes of death and physio-

logic measures of disease activity�.1 The four major

components of HRQOL are physical function, emotion-

al⁄social function, ability to work productively and

absence of specific disease-related symptoms.2, 3

There are many characteristics of Crohn’s disease that

make HRQOL measurements of particular importance in

this entity, such as the young age of onset, impact on

productivity and the recurrent nature of the disease.4

Previous investigations have shown that traditional

measurements of disease activity correlate poorly with

patient assessment in Crohn’s disease.5 Due to the

importance of HRQOL in Crohn’s disease, formal

HRQOL questionnaires are often included as secondary

outcomes in clinical trials.

The three key characteristics of HRQOL questionnaires

are validity, reliability and responsiveness.6 Two major

� 2002 Blackwell Science Ltd 1603

Correspondence to: Dr R. D. Cohen, The University of Chicago Medical

Center, MC 4076, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.E-mail: [email protected]

Aliment Pharmacol Ther 2002; 16: 1603–1609.

types of HRQOL instrument are those that address

disease-specific issues and those that measure general

well-being.7 Disease-specific questionnaires are appro-

priate for use when studying the disease for which they

were designed and validated. They are usually extreme-

ly responsive to changes within the disease, but cannot

be applied widely to other diseases. In contrast, general

questionnaires are used across disease states, and

provide a comprehensive evaluation across several

domains of function, such as emotional and social

functioning, physical health and psychological state.

They allow comparison across a broad spectrum of

diseases, but may not be responsive to a clinically

important change for the particular disease. Examples of

common disease-specific8–12 and general13–16 question-

naires utilized in Crohn’s disease are shown in Tables 1

and 2.

Health utility scales are helpful in assigning a value or

worth to a particular health state, which then allows a

comparison to be made of health status and cost utility

across disease states or between various interventions.

Examples of utility measures used in Crohn’s disease17

include the time trade-off technique,18 the standard

gamble19 and the visual analogue scale.20

HRQOL has been shown to correlate with disease

activity in Crohn’s disease in a variety of studies. For

example, standard disease activity indices, such as the

Crohn’s disease activity index and⁄or the Harvey

Bradshaw index, have been shown to correlate with

the inflammatory bowel disease questionnaire (IBDQ),21

the short IBDQ,10 the Korean-translated IBDQ,22 the

time trade-off technique,17 the standard gamble,17 the

Spanish IBDQ23 and the Dutch-translated IBDQ.24

This paper provides an overview of HRQOL in Crohn’s

disease, comparing it with that in healthy controls and

in patients with other medical disorders, as well as

between medically and surgically treated Crohn’s

disease patients, and correlating it with Crohn’s disease

activity.

METHODS

Potential articles to be included in the review were

identified first by MEDLINE search, covering all

abstracted articles from January 1966 to September

2000. The initial key words used were �Quality of Life�and �Crohn�s’, and �Quality of Life� and �Inflammatory

Bowel Disease�. The additional qualifier of �English

language� was included. Next, review articles on HRQOL

in Crohn’s disease and inflammatory bowel disease were

searched for references that were not found in the initial

MEDLINE search. Subsequent review of these other

articles not identified by the original search revealed

two additional headings that were subsequently used

for an expanded MEDLINE search: �Health Status� and

�Health Related Quality of Life�, each paired with

�Crohn�s’ or �Inflammatory Bowel Disease�. Chapters

discussing quality of life from gastrointestinal textbooks

were also searched for additional references.

Studies were excluded if they included only paediatric

patients or did not include separate data for adults, as

HRQOL issues and questionnaires differ between adults

and children. Studies comparing the outcomes of

various types of Crohn’s surgeries were also excluded,

as they were felt to be beyond the scope of the current

review. Due to the need to subject the methodologies

Table 1. Common disease-specific health-related quality of life

(HRQOL) questionnaires used in inflammatory bowel disease

Questionnaire Description

McMaster IBDQ8 32 questions; 4 dimensions: bowel,

systemic, social, emotional

IBDQ-369 36 questions; 5 dimensions: bowel,

systemic, social, emotional, functional

Short IBDQ10 10 questions; 4 dimensions: bowel,

systemic, social, emotional

RFIPC11 25 questions; 4 dimensions: disease,

body, interpersonal, sexual

Cleveland Clinic

questionnaire12

47 questions; 4 dimensions: medical,

functional, social, �life�

IBDQ, inflammatory bowel disease questionnaire; RFIPC, rating form

of inflammatory bowel disease patient concerns.

Table 2. Common general health-related quality of life (HRQOL)

questionnaires used in inflammatory bowel disease

Questionnaire Description

SIP13 136 questions; 7 dimensions: physical,

psychosocial, sleep⁄rest, eating, work,

home, recreation

PGWBI14 22 questions: subjective general well-being

EuroQOL15 5 items; 5 dimensions: mobility, personal

care, daily activities, pain, anxiety⁄depression

VAS indicating health status

SCL-9016 Psychological function

GSI Psychological distress

GSI, global symptom index; PGWBI, psychological general well-beingindex; QOL, quality of life; SIP, sickness impact profile; SCL-90,

symptom checklist-90; VAS, visual analogue scale.

1604 R. D. COHEN

� 2002 Blackwell Science Ltd, Aliment Pharmacol Ther 16, 1603–1609

and results to careful review, only full length, English

language manuscripts that clearly identified the data for

the patients with Crohn’s disease were eligible for

inclusion. Two additional requirements — the verifica-

tion of the diagnosis of Crohn’s disease by endoscopic,

radiographic or histological criteria and the use of a

validated, reliable or responsive HRQOL questionnaire

— were applied to assess the quality of the studies

included in this review.

Summary results are provided for each outcome

studied. Detailed tables are available upon request from

the author.

RESULTS

The initial MEDLINE search (�Quality of Life� and

�Crohn�s’ or �Inflammatory Bowel Disease�) uncovered

176 English language articles. Subsequent MEDLINE

search of the term �Health Status� yielded 93 articles, 28

of which were duplicates, for a net of 65 additional

articles. A third search of the term �Health Related

Quality of Life� yielded 42 articles, 35 of which were

duplicates, for a net of seven additional articles, and a

MEDLINE total of 248. There were 10 additional articles

located through searches of references of review articles

and chapters that were not duplicated on MEDLINE

searches, for a total of 258 articles. Of these, 236

articles failed to fulfil the inclusion criteria and were

excluded from further analysis, resulting in 22 studies

remaining.

The article types (and the numbers of articles) that

were excluded were: (i) surgical therapy articles without

formal quality of life analyses (46); (ii) review articles

without original HRQOL analyses (41); (iii) articles

detailing clinical course or therapeutic trials without

formal HRQOL analyses (39); (iv) articles that did not

include HRQOL analyses, or did not compare the quality

of life of the patients with a comparison group or disease

activity index (28); (v) articles in which the patients did

not have Crohn’s disease (26) or their Crohn’s diagnos-

es were unclear (1); (vi) studies containing only

paediatric patients (22); (vii) epidemiological studies

(10); (viii) surgical therapy articles with formal quality

of life analyses (8); (ix) studies of disability without

formal HRQOL analyses (6); (x) historical articles (3);

(xi) articles in which the HRQOL data were published in

a duplicate source (3); (xii) articles on health utilization

or cost without HRQOL analyses (2); (xiii) studies

appearing only in abstract form (1).

Summary results for outcome 1: comparison of HRQOL

in Crohn’s disease with that in healthy controls

Three studies had at least one instance of measurement

of HRQOL in Crohn’s disease patients compared with

that in healthy controls.9, 25, 26 Two of the three

utilized IBDQ-36.9, 26 They both found that the global

scores and the scores of all five dimensions (systemic

symptoms, bowel symptoms, functional impairment,

social impairment and emotional function) were worse

in Crohn’s disease patients. The study by Love et al. did

not pass the quality assessment as it relied on patient

recall to verify the diagnosis of Crohn’s disease and was

not validated.9 The study by Drossman et al. utilized a

self-administered sickness impact profile questionnaire

and found that Crohn’s disease patients had a worse

functional status on the psychosocial and overall scales,

but not on the physical scales.25 Utilization of a �generic�scale, such as the sickness impact profile, rather than

the disease-specific IBDQ-36, is more appropriate when

comparing a disease with a non-disease state, or when

comparing two different diseases. Thus, HRQOL appears

to be worse in Crohn’s disease patients than in healthy

controls, although physical functioning may be similar.


in Crohn’s disease with that in other medical disorders

There were a total of nine articles that had at least

one instance of measurement of HRQOL in Crohn’s

disease patients compared with patients with other

disorders.11, 12, 22, 25, 27–31 In all but two studies,22, 27

the comparison group was patients with ulcerative

colitis, and four of the studies had the same primary

author (Drossman). When general questionnaires were

used, Crohn’s disease patients scored similar to, or

worse than, ulcerative colitis patients in almost all

areas. Questionnaires specific for IBDQ and derivatives

did not show a difference between the diseases, with the

exception of studies that utilized the rating form of

inflammatory bowel disease patient concerns.11, 25, 31

Using this rating form, Crohn’s disease patients indicat-

ed more concerns with pain, energy level, being a

burden on others, achieving their full potential, finan-

cial costs and passing the disease to others, but less

cancer or incontinence concerns, than patients with

ulcerative colitis. In the two non-ulcerative colitis

studies, patients with Crohn’s disease scored similar to

those with Behcet’s disease22 and to hospitalized

CROHN’S DISEASE AND QUALITY OF LIFE 1605


controls,27 although neither study used a validated

questionnaire.

Previous authors have also published HRQOL scores of

Crohn’s disease patients using general HRQOL scales

and compared them with the scores of patients with

other diseases. For example, Patrick and Deyo compared

scores on the sickness impact profile between disease

states.32 Crohn’s disease patients scored better than

patients with most of the other disease states, including

rheumatoid arthritis, chronic obstructive pulmonary

disease (COPD), back pain, chronic pain, and haemod-

ialysis, but not as well as patients with ulcerative colitis,

myocardial infarction or cardiac arrest. Gregor et al.

reviewed studies using time trade-off assessment to

measure utilities in a variety of chronic disease states

and showed that Crohn’s disease patients had overall

better scores than patients on renal dialysis or with pre-

colectomy ulcerative colitis, but slightly worse than

patients with severe angina.17 Patients with acute

Crohn’s disease flares had utility scores similar to or

better than those measured in patients with pre-

colectomy ulcerative colitis.

In summary, it appears that patients with Crohn’s

disease have a worse quality of life than those with

ulcerative colitis, but similar to or better than those with

the other medical disorders studied. Utility scores for

Crohn’s disease patients are better than those for pre-

colectomy ulcerative colitis patients.


in active and inactive Crohn’s disease

There were a total of eight articles that had at least one

instance of measurement of HRQOL in Crohn’s disease

patients with active disease compared with Crohn’s

disease patients identified as either being in remission or

with inactive disease.10, 17, 21, 23, 24, 26, 30, 33 The eight

studies utilized a total of 15 different questionnaires, all

of which suggested significantly worse HRQOL in

patients with active disease. All of the studies utilized

validated questionnaires, and all but one passed the

quality assessment. The study that failed the quality

assessment30 had utilized a questionnaire mailed to

patients of the Crohn’s and Colitis Foundation of

America, and had acknowledged that it had not

confirmed the diagnosis of Crohn’s disease, but refer-

enced another study by the Crohn’s and Colitis Foun-

dation of America that showed a 98% correlation

between self-reported inflammatory bowel disease and

the presence of definite or probable disease by endo-

scopic, radiographic or histological criteria.34 One of the

studies utilized utility analysis, showing higher utility

scores for patients in remission than those with active or

chronic Crohn’s disease.17 Overall, HRQOL appears to

be worse in Crohn’s disease patients with active disease.

Summary results for outcome 4: correlation of HRQOL

with disease activity in Crohn’s disease

There were a total of 10 articles that had at least one

instance of comparison of HRQOL in Crohn’s disease

patients with active disease, but with different levels of

disease activity.10, 11, 17, 21–23, 25, 33, 35, 36 In nine of the

10 studies, there was a direct correlation between

worsened HRQOL and increased disease activity. Seven

of these nine studies utilized only disease-specific mea-

sures of HRQOL, while the sole study that did not find a

correlation between HRQOL and disease activity utilized

a general HRQOL scale.25 One of the studies utilized a

utility analysis.17 In all instances except one, the global

and all dimensional scores of the disease-specific ques-

tionnaires correlated HRQOL with disease activity. The

exception was the �short� version of the IBDQ,10 where

the social dimension of the HRQOL scale did not directly

correlate with worsened disease activity. All of the

HRQOL questionnaires passed the quality assessment,

except for the Korean IBDQ,22 which was not validated

in Korean, and another study by Drossman et al.,11

which did not verify the diagnosis of Crohn’s disease, as

previously discussed. Disease activity also correlated

with utility scores.17 In summary, HRQOL appears to be

directly correlated with Crohn’s disease activity.


between medically and surgically treated Crohn’s disease

patients

There were a total of four articles that had at least one

instance of comparison of HRQOL between medically

and surgically treated patients with Crohn’s dis-

ease.26, 37–39 In the study by Casellas et al., the deter-

mining factor was whether the patient had active disease

and not whether he or she had undergone previous

Crohn’s disease surgery.26 Thirlby et al. showed post-

operative improvement at various time points,37 while

most scales utilized in the study by Tillinger et al. (which

included utility studies) showed an advantage 3 and

6 months, but not 24 months, post-operatively.38 Thus,

1606 R. D. COHEN


in patients with active Crohn’s disease, HRQOL appears

to improve in the immediate post-operative period, but

not in the long term. This is consistent with the natural

history of Crohn’s disease, which gradually recurs post-

operatively in most patients.40, 41

DISCUSSION

There are many unique characteristics of Crohn’s disease,

suggesting that formalized HRQOL analysis has an

important role to play in understanding the true impact

of the disease upon patients’ lives and lifestyles, as well as

possibly guiding therapies designed to treat patients with

the disease. Crohn’s disease is a chronic, recurrent disease

with an early age of onset, yet without substantial

mortality. This suggests that patients will be dealing with

their disease throughout most of their adult life and will

need to balance the impact of their disease with their

professional, social and personal lifestyles. As evidenced

from this systematic review, Crohn’s disease patients

score as well as patients with other chronic diseases on

generic HRQOL indices, with a direct correlation between

disease activity and impaired HRQOL.

Many recent clinical trials in Crohn’s disease have

included HRQOL as a secondary outcome, often utilizing

disease-specific questionnaires together with disease

activity indices. There are numerous examples of studies

in which a drug’s beneficial impact on Crohn’s disease

activity is paralleled by an improvement in the HRQOL

score. For example, placebo-controlled trials have

shown statistically significant improvement in HRQOL

scores of patients receiving mesalamine,36 inflix-

imab,42, 43 ciclosporin,21 methotrexate44 and budeso-

nide.35, 45, 46

The importance of including HRQOL analyses is also

apparent when economic analyses are applied to the

management of patients with Crohn’s disease. Using

the data from utility studies, it is then possible to express

the impact of an intervention as a cost per quality-

adjusted life-year gained, allowing for comparison with

other disease states and assisting in decisions regarding

the allocation of health care resources. This is partic-

ularly relevant given the cost-saving environment of the

health care systems of most countries. The advent of

new, potent medical therapies often carries a higher

medication price tag, but multiple economic analyses

have suggested that such efficacious medical therapies

may, in fact, be cost saving if they decrease the

utilization of expensive health care services, such as

hospitalizations and surgeries.47–53 Surgical advances,

such as the introduction of minimally invasive surger-

ies, intestinal-sparing strictureplasties and the adapta-

tion of different approaches to anaesthesia in patients

undergoing Crohn’s disease surgeries, also hold the

promise of improving HRQOL and decreasing direct and

indirect costs.49, 54, 55

HRQOL and cost data are also important when

determining the �true� cost and impact of disease and⁄or

therapies. The most obvious case in Crohn’s disease

patients is the use of corticosteroids. Available at a

comparatively low drug cost,49 the objectionable side-

effects, coupled with the negative impact on long-term

quality of life, suggest that a more �expensive� therapy

may actually be comparable or cost saving if it is

efficacious and lacks the negative side-effect profiles

typically seen with traditional corticosteroids.56, 57

There are multiple potential future directions for

studies of HRQOL in Crohn’s disease. The findings of

this review, together with the issues touched upon

above, give further credence to the importance of

HRQOL analysis in patients with Crohn’s disease. These

findings support the continued use of HRQOL analysis in

the clinical trials of agents for the treatment of Crohn’s

disease, and suggest that greater awareness on the part

of the physician and other health care providers needs

to be given to the overall quality of life of patients with

Crohn’s disease. The development of short, validated

HRQOL questionnaires may assist in the incorporation

of quality of life analyses into the standard treatment

plans of physicians. Utility analyses will hopefully assist

in the pharmacoeconomic evaluation of the impact

of Crohn’s disease on society and the potential impact of

new technologies, allowing for the rational allocation

of health care resources.

ACKNOWLEDGEMENTS

This research was supported by Astra Zeneca.

REFERENCES

1 Guyatt G, Feeny D, Patrick D. Issues in quality-of-life mea-

surement in clinical trials. Control Clin Trials 1991; 12(4

Suppl.): 81S–90S.

2 Testa MA, Simonson DC. Assessment of quality-of-life out-

comes. N Engl J Med 1996; 334(13): 835–40.

3 Fitzpatrick R, Fletcher A, Gore S, et al. Quality of life mea-

sures in health care. I: Applications and issues in assessment.

Br Med J 1992; 305(6861): 1074–7.



4 Truelove SC, Pena AS. Course and prognosis of Crohn’s

disease. Gut 1976; 17(3): 192–201.

5 Hodgson HJ. Assessment of drug therapy in inflammatory

bowel disease. Br J Clin Pharmacol 1982; 14(2): 159–70.

6 Guyatt GH, Feeny DH, Patrick DL. Measuring health-related

quality of life. Ann Intern Med 1993; 118(8): 622–9.

7 Irvine EJ. Quality of life issues in patients with inflammatory

bowel disease. Am J Gastroenterol 1997; 92(12 Suppl.):

18S–24S.

8 Guyatt G, Mitchell A, Irvine EJ, et al. A new measure of

health status for clinical trials in inflammatory bowel dis-

ease. Gastroenterology 1989; 96(3): 804–10.

9 Love JR, Irvine EJ, Fedorak RN. Quality of life in inflam-

matory bowel disease. J Clin Gastroenterol 1992; 14(1):

15–9.

10 Irvine EJ, Zhou Q, Thompson AK. The Short Inflammatory

Bowel Disease Questionnaire: a quality of life instrument for

community physicians managing inflammatory bowel

disease. CCRPT Investigators. Canadian Crohn’s Relapse

Prevention Trial. Am J Gastroenterol 1996; 91(8): 1571–8.

11 Drossman DA, Leserman J, Li ZM, et al. The rating form of

IBD patient concerns: a new measure of health status. Psy-

chosom Med 1991; 53(6): 701–12.

12 Farmer RG, Easley KA, Farmer JM. Quality of life assessment

by patients with inflammatory bowel disease. Cleve Clin J

Med 1992; 59(1): 35–42.

13 Bergner M, Bobbitt RA, Carter WB, et al. The Sickness Impact

Profile: development and final revision of a health status

measure. Med Care 1981; 19(8): 787–805.

14 Dupuy H. The psychological general well-being (PGWB)

index. In: Wegner N, Mattson M, Fuberg C, eds. Assessment

of Quality of Life in Clinical Trials of Cardiovascular Thera-

pies. New York: Le Jacq, 1984.

15 Badia X, Schiaffino A, Alonso J, et al. Using the EuroQOl 5-D

in the Catalan general population: feasibility and construct

validity. Qual Life Res 1998; 7(4): 311–22.

16 Derogatis LR, Rickels K, Rock AF. The SCL-90 and the MMPI:

a step in the validation of a new self-report scale. Br J Psy-

chiatr 1976; 128: 280–9.

17 Gregor JC, McDonald JWD, Klar N, et al. An evaluation of

utility measurement in Crohn’s disease. Inflamm Bowel Dis

1997; 3(4): 265–76.

18 Sackett DL, Torrance GW. The utility of different health

states as perceived by the general public. J Chronic Dis 1978;

31(11): 697–704.

19 Richardson J. Cost utility analysis: what should be mea-

sured? Soc Sci Med 1994; 39(1): 7–21.

20 Froberg DG, Kane RL. Methodology for measuring health-

state preferences — II. Scaling methods. J Clin Epidemiol

1989; 42(5): 459–71.

21 Irvine EJ, Feagan B, Rochon J, et al. Quality of life: a valid and

reliable measure of therapeutic efficacy in the treatment of

inflammatory bowel disease. Canadian Crohn’s Relapse

Prevention Trial Study Group. Gastroenterology 1994;

106(2): 287–96.

22 Kim WH, Cho YS, Yoo HM, et al. Quality of life in Korean

patients with inflammatory bowel diseases: ulcerative colitis,

Crohn’s disease and intestinal Behcet’s disease. Int J Colo-

rectal Dis 1999; 14(1): 52–7.

23 Lopez-Vivancos J, Casellas F, Badia X, et al. Validation of the

Spanish version of the inflammatory bowel disease ques-

tionnaire on ulcerative colitis and Crohn’s disease. Digestion

1999; 60(3): 274–80.

24 Russel MG, Pastoor CJ, Brandon S, et al. Validation of the

Dutch translation of the Inflammatory Bowel Disease Ques-

tionnaire (IBDQ): a health-related quality of life question-

naire in inflammatory bowel disease. Digestion 1997; 58(3):

282–8.

25 Drossman DA, Patrick DL, Mitchell CM, et al. Health-related

quality of life in inflammatory bowel disease. Functional

status and patient worries and concerns. Dig Dis Sci 1989;

34(9): 1379–86.

26 Casellas F, Lopez-Vivancos J, Badia X, et al. Impact of surgery

for Crohn’s disease on health-related quality of life. Am J

Gastroenterol 2000; 95(1): 177–82.

27 Sorensen VZ, Olsen BG, Binder V. Life prospects and quality

of life in patients with Crohn’s disease. Gut 1987; 28(4):

382–5.

28 Verissimo R, Mota-Cardoso R, Taylor G. Relationships

between alexithymia, emotional control, and quality of life

in patients with inflammatory bowel disease. Psychother

Psychosom 1998; 67(2): 75–80.

29 Drossman DA, Leserman J, Mitchell CM, et al. Health status

and health care use in persons with inflammatory bowel

disease. A national sample. Dig Dis Sci 1991; 36(12): 1746–

55.

30 Drossman DA, Li Z, Leserman J, Patrick DL. Ulcerative colitis

and Crohn’s disease health status scales for research and

clinical practice. J Clin Gastroenterol 1992; 15(2): 104–12.

31 Moser G, Tillinger W, Sachs G, et al. Disease-related worries

and concerns: a study on out-patients with inflammatory

bowel disease. Eur J Gastroenterol Hepatol 1995; 7(9):

853–8.

32 Patrick DL, Deyo RA. Generic and disease-specific measures

in assessing health status and quality of life. Med Care 1989;

27(3 Suppl.): S217–32.

33 Martin A, Leone L, Fries W, et al. Quality of life in inflamma-

tory bowel disease. Ital J Gastroenterol 1995; 27(8): 450–4.

34 Baird DD, Narendranathan M, Sandler RS. Increased risk of

preterm birth for women with inflammatory bowel disease.

Gastroenterology 1990; 99(4): 987–94.

35 Irvine EJ, Greenberg GR, Feagan BG, et al. Quality of life

rapidly improves with budesonide therapy for active Crohn’s

disease. Canadian Inflammatory Bowel Disease Study Group.

Inflamm Bowel Dis 2000; 6(3): 181–7.

36 Singleton JW, Hanauer S, Robinson M. Quality-of-life results

of double-blind, placebo-controlled trial of mesalamine in

patients with Crohn’s disease. Dig Dis Sci 1995; 40(5): 931–5.

37 Thirlby RC, Land JC, Fenster LF, et al. Effect of surgery on

health-related quality of life in patients with inflammatory

bowel disease: a prospective study. Arch Surg 1998; 133(8):

826–32.

38 Tillinger W, Mittermaier C, Lochs H, et al. Health-related

quality of life in patients with Crohn’s disease: influence of

1608 R. D. COHEN


surgical operation — a prospective trial. Dig Dis Sci 1999;

44(5): 932–8.

39 Yazdanpanah Y, Klein O, Gambiez L, et al. Impact of surgery

on quality of life in Crohn’s disease. Am J Gastroenterol

1997; 92(10): 1897–900.

40 McLeod RS, Wolff BG, Steinhart AH, et al. Risk and signifi-

cance of endoscopic⁄radiological evidence of recurrent Cro-

hn’s disease. Gastroenterology 1997; 113(6): 1823–7.

41 Rutgeerts P, Geboes K, Vantrappen G, et al. Predictability of

the postoperative course of Crohn’s disease. Gastroenterology

1990; 99(4): 956–63.

42 Targan SR, Hanauer SB, van Deventer SJ, et al. A short-term

study of chimeric monoclonal antibody cA2 to tumor

necrosis factor alpha for Crohn’s disease. Crohn’s Disease

cA2 Study Group. N Engl J Med 1997; 337(15): 1029–35.

43 Rutgeerts P, D’Haens G, Targan S, et al. Efficacy and safety of

retreatment with anti-tumor necrosis factor antibody (inf-

liximab) to maintain remission in Crohn’s disease. Gast-

roenterology 1999; 117(4): 761–9.

44 Feagan BG, Rochon J, Fedorak RN, et al. Methotrexate for the

treatment of Crohn’s disease. The North American Crohn’s

Study Group Investigators [see comments]. N Engl J Med

1995; 332(5): 292–7.

45 Bar-Meir S, Chowers Y, Lavy A, et al. Budesonide versus

prednisone in the treatment of active Crohn’s disease. The

Israeli Budesonide Study Group. Gastroenterology 1998;

115(4): 835–40.

46 Thomsen OO, Cortot A, Jewell D, et al. A comparison of

budesonide and mesalamine for active Crohn’s disease.

International Budesonide–Mesalamine Study Group. N Engl

J Med 1998; 339(6): 370–4.

47 Hay AR, Hay JW. Inflammatory bowel disease: medical cost

algorithms. J Clin Gastroenterol 1992; 14(4): 318–27.

48 Hay JW, Hay AR. Inflammatory bowel disease: costs-of-ill-

ness. J Clin Gastroenterol 1992; 14(4): 309–17.

49 Cohen RD. The cost of Crohn’s disease: drugs or surgery?

Biodrugs 2000; 14(5): 331–44.

50 Cohen RD, Larson LR, Roth JR, et al. The cost of hospital-

izations in Crohn’s disease. Am J Gastroenterol 2000; 95(2):

524–30.

51 Silverstein MD, Loftus EV, Sandborn WJ, et al. Clinical course

and costs of care for Crohn’s disease: Markov model analysis

of a population-based cohort. Gastroenterology 1999;

117(1): 49–57.

52 Bernstein CN, Papineau N, Zajaczkowski J, et al. Direct hos-

pital costs for patients with inflammatory bowel disease in a

Canadian tertiary care university hospital. Am J Gastroen-

terol 2000; 95(3): 677–83.

53 Feagan BG, Vreeland MG, Larson LR, et al. Annual cost of

care for Crohn’s disease: a payor perspective. Am J Gastro-

enterol 2000; 95(8): 1955–60.

54 Hurst RD, Cohen RD. The role of laparoscopy and strictu-

replasty in the management of inflammatory bowel disease.

In: Lichtenstein GR, ed. Seminars in Gastrointestinal Disease.

Inflammatory Bowel Disease. Philadelphia: W. B. Saunders,

2000: 10–7.

55 Grass JA. The role of epidural anesthesia and analgesia in

postoperative outcome. Anesthesiol Clin North Am 2000;

18(2): 407–28.

56 Valentine JF, Sninsky CA. Prevention and treatment of

osteoporosis in patients with inflammatory bowel disease.

Am J Gastroenterol 1999; 94(4): 878–83.

57 Gokhale R, Favus MJ, Karrison T, et al. Bone mineral density

assessment in children with inflammatory bowel disease.

Gastroenterology 1998; 114(5): 902–11.



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The quality of life in patients with Crohn's disease