Assessing health-related quality of life in patients with inflammatory bowel disease in Zhejiang, China

CLINICAL ISSUES

Assessing health-related quality of life in patients with inflammatory

bowel disease in Zhejiang, China

Yunxian Zhou, Weihong Ren, Elizabeth Jan Irvine and Dagan Yang

Aims. The aim of this study was to assess health-related quality of life in patients with inflammatory bowel disease in Zhejiang,

Mainland China.

Background. The incidence of inflammatory bowel disease in China is believed to be low but has been increasing in the past

decade. The quality of life of Chinese patients with inflammatory bowel disease is unknown.

Design. A cross-sectional study.

Methods. The study was conducted in 92 patients with inflammatory bowel disease in Zhejiang, China, 52 with ulcerative

colitis and 40 with Crohn’s disease. Health-related quality of life was measured by the Chinese version of the Inflammatory

Bowel Disease Questionnaire and Short Form-36, respectively. Disease activity was assessed by the Walmsley and Harvey–

Bradshaw simple indices for ulcerative colitis and Crohn’s disease, respectively. Demographic and clinical variables were also

recorded. Short Form-36 data from the study sample were compared with a reference population of 1688 Chinese people

residing in Hangzhou, Zhejiang, China.

Results. No significant health-related quality of life differences were found between patients with ulcerative colitis and

Crohn’s disease (p > 0Æ05). Pooled data showed that inflammatory bowel disease patients with active disease had signifi-

cantly lower scores for all eight dimensions of Short Form-36 compared to those in remission (p < 0Æ01); those with active

disease scored significantly lower than population norms in all dimensions of Short Form-36 except mental health (p < 0Æ05);

whereas those in remission scored significantly lower than population norms in role physical (p < 0Æ01) and general health

dimensions (p < 0Æ05). The regression analyses identified only disease activity index and employment status to explain

variations in health-related quality of life (p < 0Æ01).

Conclusions. Inflammatory bowel disease similarly impairs health-related quality of life in patients with both ulcerative colitis

and Crohn’s disease.

Relevance to clinical practice. The results suggest that any interventions that produce a stable clinical remission, whether

medical or surgical, allowing patients to return to their usual work position can decrease the disease impact on their daily lives.

Key words: Crohn’s disease, health-related quality of life, inflammatory bowel disease, ulcerative colitis

Accepted for publication: 27 May 2009

Introduction

Inflammatory bowel diseases (IBD), includes both ulcerative

colitis (UC) and Crohn’s disease (CD), which are chronic,

recurrent inflammatory disorders of the gastrointestinal

system with unknown origins and uncertain pathogenesis

(Fiocchi 1998). These two diseases are histologically different

but share many of the same symptoms such as diarrhoea,

Authors: Yunxian Zhou, Master of Medicine, RN, PhD student,

Department of Nursing, The Second Affiliated Hospital, College of

Medicine, Zhejiang University, Hangzhou, Zhejiang, China;

Weihong Ren, Bachelor of Nursing, RN, Department of Nursing,

The Second Affiliated Hospital, College of Medicine, Zhejiang

University, Hangzhou, Zhejiang, China; Elizabeth Jan Irvine, MD,

Professor of Medicine, Division of Gastroenterology, University of

Toronto & St Michael’s Hospital, Toronto, ON, Canada; Dagan

Yang, Master of Engineering, Department of Laboratory, The First

Affiliated Hospital, College of Medicine, Zhejiang University,

Hangzhou, Zhejiang, China

Correspondence: Dagan Yang, Department of Laboratory, The First

Affiliated Hospital, College of Medicine, Zhejiang University,

Hangzhou 31003, Zhejiang, China. Telephone: +86 571 87236380.

E-mail: [email protected]

� 2010 Blackwell Publishing Ltd, Journal of Clinical Nursing, 19, 79–88 79

doi: 10.1111/j.1365-2702.2009.03020.x

rectal bleeding and abdominal pain. UC is characterised by

recurrent diffuse inflammation involving the surface mucosal

and submucosal layers of the colon and rectum (Lennard-

Jones 1989). CD is an inflammatory disease involving the full

thickness of the intestinal wall, which can affect any part of

the gastrointestinal tract (Lennard-Jones 1989). These dis-

eases have their highest incidence between 15–30 years of

age, but without substantial mortality. As a result, they have

a great impact during a very active period of an individual’s

life (Hendriksen & Binder 1980).

The conventional clinical indices such as endoscopic and

disease activity indices consider more powerfully the physi-

ological and pathological changes in the disease and are thus

inadequate to estimate the full impact of the disease on

patients’ everyday lives. It is important, therefore, to measure

patients’ health-related quality of life (HRQoL) to reflect

their subjective experience of health better (Zahn et al. 2006)

and to quantify the broader impact of the disease and/or

therapy upon patients’ lives, as well as provide guidance for

the management of the disease.

IBDs are common chronic conditions in Western countries.

Incidences for UC and CD in Europe and the USA were

reported to be 10–20/105 and 5–10/105 respectively; and the

prevalence of UC and CD were 100–200/105 and 50–100/105

respectively (Carter et al. 2004). There is considerable

international evidence that IBD impairs patients’ HRQoL

(Casellas et al. 2001, 2002, Guthrie et al. 2002, Bernklev

et al. 2005a,b, 2006, Irvine 2008), and CD patients appear to

have a worse HRQoL compared to UC patients (Drossman

et al. 1991, Farmer et al. 1992). Furthermore, while many

existing studies conclude that IBD active patients are more

impaired than patients in remission, there is some disagree-

ment over whether HRQoL is impaired only when the disease

is active, or whether it is also impaired during remission.

The incidence and prevalence of IBD are believed to be

much lower in China compared to Western countries even

though there are no large population-based epidemiological

studies in existence (Wang et al. 2007). Hospital-based

studies estimate the prevalence of UC and CD in China to

be 11Æ6/105 (Chinese IBD Working Group 2006) and 1Æ4/105

(Ouyang et al. 2005, Wang et al. 2007), respectively. In

addition, there are some significant identified differences in

clinical characteristics of UC and CD in China compared to

Western countries (APDW 2004 Chinese IBD Working

Group 2006, Chinese IBD Working Group 2006), such as

relative male predominance, milder disease course, fewer

severe cases, fewer extra-intestinal manifestations and bowel

complications. Thus, genetic, environmental and cultural

determinants of IBD and related HRQoL may be different in

China from other countries.

The incidence of IBD in China has been lower than in

Western countries, but has increased rapidly in the past

decade (Jiang & Cui 2002). The most recent review (Hu et al.

2007) of the Chinese literature reported 143,511 cases of IBD

(140,114 UC and 3397 CD) in the last 15 years, with a more

marked increase in UC cases. This suggests that IBD may

become a more prevalent chronic disease in China along with

the ongoing westernisation of lifestyles (Ouyang et al. 2005).

The quality of life of Chinese patients with IBD is unknown

but is nonetheless of interest and significance given the

potential volume of patients in the most populous country in

the world (Leong et al. 2003). In addition, as the optimal

disease management aims at achieving remission, a compar-

ison of active and remission IBD patients with the general

population is necessary to estimate its impact on daily life.

Furthermore, identifying the factors that are involved in the

impairment of HRQoL in IBD patients is important as it may

then be possible to modify some of these factors and thereby

improve patients’ HRQoL. Therefore, the aims of this study

were to (1) assess the HRQoL in patients with IBD in

Zhejiang, Mainland China, (2) compare the HRQoL of UC

patients with CD patients, (3) compare the HRQoL in patients

with IBD in active and remission status with population

normative values and (4) evaluate the influence of demo-

graphic and clinical variables on HRQoL in IBD patients.

Method

Patients

A consecutive series of Mainland Chinese patients with IBD

were recruited from hospital wards and outpatient clinics of a

large university affiliated teaching hospital in Hangzhou, the

capital of Zhejiang Province, southeast Mainland China from

June 2005–May 2006. The total population of Zhejiang

Province was 49,760,000 on 1 November 2006. The hospital

has 1900 beds, and it provides health care services for both

patients with health insurance and those without. The main

inclusion criterion was that participants have a definite

diagnosis of UC or CD for at least six-month duration. The

diagnosis of UC or CD was made according to the Lennard-

Jones criteria (Lennard-Jones 1989). The exclusion criteria

were the inability to comprehend or complete the self-admin-

istered questionnaires or the presence of a psychiatric disorder,

stoma or malignancy. The hospital ethics committee approved

the protocol, and written informed consent was obtained from

the study subjects. Some of the demographic variables (gender,

age, education level, marriage status, employment status) and

clinical variables (disease type, disease duration, disease

activity index, extra-intestinal manifestations, intestinal

Y Zhou et al.

80 � 2010 Blackwell Publishing Ltd, Journal of Clinical Nursing, 19, 79–88

surgical history, number of hospitalisations because of IBD

in the past two years and number of clinic visits because of

IBD in the past six months) were also obtained.

Assessment of HRQoL

HRQoL was measured by a disease-specific and a generic

questionnaire: the Mainland Chinese version of the Inflam-

matory Bowel Disease Questionnaire (IBDQ) (Ren et al.

2007) and the Chinese version of the Medical Outcomes

Study Short Form-36 (SF-36) (Wan et al. 1998) respectively.

The original IBDQ was initially developed and validated in

Canada in 1989 (Guyatt et al. 1989) and more fully validated

later (Irvine et al. 1994). It includes 32 items grouped into four

dimensions of health: bowel symptoms (10 questions), sys-

temic symptoms (five questions), emotional function (12

questions) and social function (five questions) (Guyatt et al.

1989). Each question is scored on a seven-point Likert scale,

ranging from 1 (represents a very severe problem)–7 (repre-

sents no problem at all), reflecting the quality of life of the

previous two weeks. The total IBDQ score ranges from

32–224. The validity, reliability and sensitivity to detect

important changes in health status of IBDQ have been

extensively evaluated, and it has been translated and cross-

culturally validated in several different language versions, all

with good reliability and validity (Russel et al. 1997, Han

et al. 1998, Lopez-Vivancos et al. 1999b, Cheung et al. 2000,

Hjortswang et al. 2001, Pallis et al. 2001, Bernklev et al.

2002, Hashimoto et al. 2003). The version used in this study

was the Mainland Chinese version of IBDQ. The translation

and validation have been reported elsewhere (Ren et al. 2007).

The Cronbach’s a for each subscale of the Chinese translation

was 0Æ94–0Æ95; test–retest reliability was 0Æ69–0Æ93.

HRQoL was also assessed using SF-36 (Wan et al. 1998), a

widely accepted generic instrument that assesses the eight

dimensions of physical functioning (PF), role physical (RP),

bodily pain (BP), general health perception (GH), vitality

(VT), social functioning (SF), role emotional (RE) and mental

health (MH). The total score for all subscales is 145, with a

standardised norm score for each subscale range from 0–100.

The Chinese version of SF-36 has been validated and used to

assess a wide variety of medical conditions in Mainland

China including gastrointestinal disease (Si et al. 2003, Xiong

et al. 2004). The Cronbach’s a was 0Æ93, and the test–retest

reliability was 0Æ78 in this study.

Disease activity indices

A gastrointestinal physician, blinded to the results of the

IBDQ and SF-36, independently interviewed the UC and CD

patients at the time of completion of the questionnaires and

scored the disease activity by the means of the Walmsley

simple colitis activity index (CAI) (Walmsley et al. 1998) and

the Harvey–Bradshaw simple index (HBI) (Harvey & Brad-

shaw 1980) respectively. The CAI includes bowel frequency

during the day and night, urgency of defacation, blood in

stool, general well-being and extra-colonic features. The total

scores ranged from 0–>16, with a score <4 indicating

‘remission’ and a score of at least 4 indicating ‘active’. The

HBI includes general well-being, abdominal pain, number of

liquid stools per day, abdominal mass and complications.

Here, the total scores range from 0–>12 and again, a score

of <4 indicates ‘remission’ and a score of at least 4 indicating

‘active’. Higher scores are associated with more severe

disease. These two indices were chosen, because they are

widely used internationally, rely entirely on symptoms of the

previous 24 hours and do not require any invasive proce-

dures. They also correlate very well with the more complex

disease severity indices (Harvey & Bradshaw 1980, Walmsley

et al. 1998).

General population sample

SF-36 data for the general population in Hangzhou were

collected in a previous study by Wang et al. (2001) and Li

et al. (2003) from a sample of 1000 households (with people

aged 18 years and older reflecting the age distribution of our

IBD population) using multi-staged mixed sampling to fully

represent the general population from two districts (173,765

households) in Hangzhou, Zhejiang Province, China. Of

1972 questionnaires sent, 1688 (85Æ6%) were returned.

Among the respondents, 50Æ9% were male; the mean age

was 46Æ0 years; 15Æ8% had primary education or less, 66Æ4%

had secondary education, and 17Æ8% had tertiary education

(college or university) or above (Wang et al. 2001, Li et al.

2003). These data were used for comparison with our IBD

patients.

Statistical analysis

Statistical analyses were performed using the SPSSSPSS version

13.0 (SPSS Inc., Chicago, IL, USA) for Windows. Frequen-

cies, medians, means, standard deviations (SD) and 95%

confidence intervals (95% CI) were used for descriptive

statistics. Differences in the demographic and clinical vari-

ables between UC and CD groups, active IBD group,

remission IBD group and the population norm were evalu-

ated by Student’s t-test (for continuous data) and Chi-square

test (for categorical data). Student’s t-test and analysis of

covariance (ANCOVAANCOVA) were used in comparing the HRQoL of

Clinical issues Quality of life in inflammatory bowel disease patients


the two groups with age, gender and educational level as

covariate(s) when appropriate. To explore the factors that

were associated with HRQoL in patients with IBD, multi-

variable linear regression modelling was applied. The IBDQ

and the SF-36 total scores were used as dependent variables,

and demographic variables (gender, age, educational level,

employment status) and clinical variable (disease activity

index) were used as explanatory variables. The choice of

explanatory variables was based on an extensive literature

review (Irvine et al. 1998, Casellas et al. 2002, Guthrie

et al. 2002, Pallis et al. 2002, Andersson et al. 2003,

Hjortswang et al. 2003, Blanco et al. 2005, Han et al.

2005, Bernklev et al. 2006, Canavan et al. 2006, Graff et al.

2006, Zahn et al. 2006, Gibson et al. 2007) and clinical

experience, while also taking into account our sample size. As

a result, a forced entry approach of regression modelling was

applied in this study to estimate the contribution of the

independent variables to the explained variance of the

subjects’ HRQoL. Two explanatory variables, educational

level and employment status, were categorical variables with

three levels. These variables were transformed appropriately

to two sets of dummy variables. For all analyses, a two-sided

alpha for statistical significance was set at 0Æ05.

Results

Patient characteristics

One hundred and two consecutive Chinese patients with IBD

who met the inclusion criteria were approached for partic-

ipation. Ten patients were excluded for the following

reasons: (four patients), stoma (two patients), anxiety (one

patient), severe complications (two patients) and poor com-

prehension (one patient). Ninety-two patients were included

in the study; 52 with UC and 40 with CD. The demographic

characteristics of the 10 non-participants were similar to the

92 participants. As the sample is a non-selective continuous

hospital IBD cohort (all eligible subjects during the study

period were approached and invited to participate except

those who refused to participate), with a high response rate, it

is deemed representative of IBD population of that hospital.

While the majority of the patients were recruited from the

outpatient clinic, 29 were hospitalised at the time of HRQoL

assessment. The demographic and clinical data of the patients

are listed in Table 1. There were more males than females

included in the patient sample, and the gender distribution

was similar in patients with UC and CD (p = 0Æ253).

The mean age in the CD group was significantly lower than

in the UC group: 35Æ7 vs. 45Æ0 years (p = 0Æ002), and patients

in the CD group had higher education than in the UC patients

(p = 0Æ001). The median disease activity index was similar at

3Æ0 and 2Æ0 for UC and CD respectively, (p = 0Æ100) and

59Æ8% of all patients were in remission.

HRQoL in patients with IBD

There was a wide range of IBDQ total scores in patients with

IBD, with the lowest being 68Æ0 and the highest being 217Æ0.

The mean scores for bowel domain, systemic domain, emo-

tional domain and social function domain were 58Æ1 (SD 8Æ8),

Table 1 Demographic and clinical

characteristics of patients with IBDItem

IBD

(n = 92)

UC

(n = 52)

CD

(n = 40)

Males (%) 60Æ9 55Æ8 67Æ5Mean age (years) (SD) 40Æ9 (15Æ3) 45Æ0 (16Æ7) 35Æ7 (11Æ6)

Education level (%)

Primary or less 28Æ3 40Æ4 12Æ5Secondary 45Æ6 46Æ1 45Æ0Tertiary or above 26Æ1 13Æ5 42Æ5

Marital status (%)

Single 23Æ9 17Æ3 32Æ5Married 76Æ1 82Æ7 67Æ5

Employment status (%)

Continue work 43Æ5 38Æ5 50Æ0Work and sick leave alternate 40Æ2 51Æ9 25Æ0Long-term sick leave 16Æ3 9Æ6 25Æ0

Mean disease duration (months) (SD) 39Æ5 (42Æ5) 30Æ5 (29Æ8) 50Æ9 (52Æ9)

Extra-intestinal manifestations (% of presence) 14Æ1 9Æ6 20Æ0Previous history of intestinal surgery (% of presence) 25Æ0 5Æ8 50Æ0Remissions (%) 59Æ8 55Æ8 65Æ0

CD, Crohn’s disease; IBD, inflammatory bowel diseases; UC, ulcerative colitis.

Y Zhou et al.


24Æ0 (SD 6Æ3), 67Æ2 (SD 12Æ0) and 27Æ8 (SD 6Æ7) respectively.

As there were no significant differences in total and dimen-

sional scores between UC and CD patients using either the

IBDQ or SF-36 (p > 0Æ05) (Tables 2 and 3), we subsequently

analysed all the cases together.

HRQoL in active or remission IBD patients and the

population norm

The SF-36 total score for 92 IBD patients ranged from 51Æ10–

136Æ40. To explore whether HRQoL is impaired only when

the disease is active, or whether it is also impaired during

remission, IBD patients were divided into two groups

according to disease activity indices. There were 55 patients

in the remission group and 37 in the active group. The gender

distribution across the active group, remission group and

population norm was similar (p = 0Æ146). The mean age was

similar between the active and norm groups (46Æ4 vs.

46Æ0 years old, p = 0Æ857), but it was significantly different

across active and remission groups (46Æ4 vs. 37Æ4 years old,

p = 0Æ004) and remission and norm groups (37Æ4 vs.

46Æ0 years old, p < 0Æ001). The distribution of education

level was similar between the active and remission groups

(p = 0Æ134), the active and norm groups (p = 0Æ183), but not

the remission and norm groups (p < 0Æ001). Therefore, age

was used as a covariate when comparing the SF-36 score

between the active and remission groups. As Table 4

indicates, IBD patients with an active status scored signif-

icantly lower in all eight dimensions than those in remission

(p < 0Æ01). Further, as Table 5 indicates, IBD patients with

an active status scored significantly lower in all dimensions

except MH compared to the population norm (p < 0Æ05). In

contrast, IBD patients in remission scored significantly lower

in only the RP (p < 0Æ01) and GH (p < 0Æ05) dimensions

Table 2 The comparison of Inflammatory

Bowel Disease Questionnaire score in

patients with UC (n = 52) and CD (n = 40)

expressed by mean (95% CI)

Item UC CD p-value

Bowel 57Æ1 (54Æ5–59Æ7) 59Æ3 (56Æ8–61Æ8) 0Æ582

Systemic 23Æ5 (21Æ9–25Æ1) 24Æ7 (22Æ5–26Æ9) 0Æ742

Emotional 67Æ2 (64Æ0–70Æ5) 67Æ2 (63Æ2–71Æ1) 0Æ650

Social function 27Æ9 (26Æ0–29Æ8) 27Æ6 (25Æ5–29Æ7) 0Æ529

Total score 175Æ7 (167Æ4–184Æ0) 178Æ8 (169Æ2–188Æ4) 0Æ922

CD, Crohn’s disease; UC, ulcerative colitis.

ANCOVAANCOVA, adjusted for age and education level.

Table 3 The comparison of Short Form-36

score in patients with UC (n = 52) and

CD (n = 40) expressed by mean (95% CI)

Item UC CD p-value

PF 82Æ0 (77Æ5–86Æ6) 82Æ6 (77Æ1–88Æ2) 0Æ457

RP 44Æ7 (33Æ4–56Æ0) 45Æ0 (31Æ4–58Æ6) 0Æ423

BP 74Æ1 (67Æ5–80Æ9) 74Æ9 (67Æ2–82Æ5) 0Æ706

GH 45Æ9 (40Æ3–51Æ4) 44Æ7 (39Æ0–50Æ4) 0Æ240

VT 54Æ5 (48Æ2–60Æ8) 59Æ3 (52Æ7–65Æ8) 0Æ903

SF 73Æ3 (65Æ6–81Æ0) 73Æ1 (65Æ4–80Æ7) 0Æ844

RE 70Æ5 (60Æ2–80Æ9) 67Æ5 (55Æ3–79Æ7) 0Æ953

MH 73Æ8 (69Æ0–78Æ6) 69Æ1 (62Æ8–75Æ4) 0Æ061

Total score 107Æ8 (102Æ8–112Æ9) 107Æ5 (101Æ3–113Æ6) 0Æ410

BP, bodily pain; CD, Crohn’s disease; GH, general health perception; MH, mental health; PF,

physical functioning; RE, role emotional; RP, role physical; SF, social functioning; UC, ulcerative

colitis; VT, vitality.

ANCOVAANCOVA, adjusted for age and education level.

Table 4 The comparison of Short Form-36 score in active and

remission IBD patients expressed in mean (SD)

Item

Active IBD

(n = 37)

Remission IBD

(n = 55) p-value

PF 75Æ5 (20Æ1) 86Æ8 (12Æ2) 0Æ010

RP 18Æ9 (27Æ9) 62Æ3 (39Æ6) 0Æ000

BP 62Æ3 (23Æ1) 82Æ7 (20Æ9) 0Æ000

GH 37Æ5 (17Æ4) 50Æ6 (18Æ5) 0Æ003

VT 42Æ4 (20Æ7) 66Æ1 (16Æ9) 0Æ000

SF 62Æ5 (25Æ3) 80Æ4 (23Æ9) 0Æ001

RE 47Æ8 (36Æ5) 83Æ6 (30Æ7) 0Æ000

MH 60Æ4 (18Æ6) 79Æ4 (14Æ0) 0Æ000

BP, bodily pain; GH, general health perception; IBD, inflammatory

bowel diseases; MH, mental health; PF, physical functioning; RE,

role emotional; RP, role physical; SF, social functioning; VT, vitality.

ANCOVAANCOVA, adjusted for age.



compared with the population norm. Surprisingly, IBD

patients in remission also scored significantly higher in the

PF, VT and MH dimensions compared to the population

norm (p < 0Æ01).

Factors influencing HRQoL in IBD patients

In exploring factors that were associated with HRQoL in IBD

patients, both the IBDQ and the SF-36 total score regression

models revealed that among these explanatory variables, only

the disease activity index and employment status have an

influence on HRQoL (p < 0Æ01), and this model explained

54–55% of the variance (Table 6). More specifically, the

disease activity index appears to be the most important factor

and had a negative influence on HRQoL in both models, with

a higher disease activity score predicting worse HRQoL

(p < 0Æ01). Employment status was also significant, and

those who continued to work had an average IBDQ score of

21Æ10 higher than those who were on long-term sick leave

(p < 0Æ01). Further, those who alternated between work and

sick leave had an average IBDQ score of 25Æ04 higher than

the long-term leave group (p < 0Æ01). The SF-36 model also

Table 5 The comparison of Short Form-36 score in active and remission IBD patients with population norm expressed in mean (SD)

Item

Active IBD

(n = 37)

Remission IBD

(n = 55)

Population norm*

(n = 1688)

Active/norm

p-value

Remission/norm

p-value

PF 75Æ5 (20Æ1) 86Æ8 (12Æ2) 82Æ2 (19Æ8) 0Æ050 0Æ007

RP 18Æ9 (27Æ9) 62Æ3 (39Æ6) 81Æ2 (33Æ6) 0Æ000 0Æ001

BP 62Æ3 (23Æ1) 82Æ7 (20Æ9) 81Æ5 (20Æ5) 0Æ000 0Æ683

GH 37Æ5 (17Æ4) 50Æ6 (18Æ5) 56Æ7 (20Æ2) 0Æ000 0Æ018

VT 42Æ4 (20Æ7) 66Æ1 (16Æ9) 52Æ0 (20Æ9) 0Æ008 0Æ000

SF 62Æ5 (25Æ3) 80Æ4 (23Æ9) 83Æ0 (17Æ8) 0Æ000 0Æ424

RE 47Æ8 (36Æ5) 83Æ6 (30Æ7) 84Æ4 (32Æ4) 0Æ000 0Æ854

MH 60Æ4 (18Æ6) 79Æ4 (14Æ0) 59Æ7 (22Æ7) 0Æ812 0Æ000

BP, bodily pain; GH, general health perception; IBD, inflammatory bowel diseases; MH, mental health; PF, physical functioning; RE, role

emotional; RP, role physical; SF, social functioning; VT, vitality.

*Population norms as reported by Li et al. (2003); One-sample t-test. The age in remission group is significantly younger than population norm

(37Æ4 vs. 46Æ0 years old), and it was not adjusted.

Table 6 Factors influencing health-related

quality of life in inflammatory bowel

diseases patients measured using IBDQ

and SF-36

Variables B SE b p-value

IBDQ total score

Disease activity index �9Æ25 1Æ19 �0Æ63 0Æ000

Occupational status

Continued work vs. long-term sick leave 21Æ10 6Æ33 0Æ35 0Æ001

Alternate vs. long-term sick leave 25Æ04 6Æ68 0Æ42 0Æ000

Education level

Primary vs. tertiary education 2Æ79 5Æ51 0Æ05 0Æ615

Secondary vs. tertiary education 5Æ76 6Æ89 0Æ09 0Æ405

Age �0Æ03 0Æ18 �0Æ01 0Æ884

Gender (male = 0, female = 1) �0Æ35 4Æ77 �0Æ01 0Æ942

Adjusted R2 0Æ55

SF-36 total score

Disease activity index �5Æ41 0Æ75 �0Æ59 0Æ000

Occupational status

Continue work vs. long-term sick leave 16Æ30 3Æ97 0Æ43 0Æ000

Alternate vs. long-term sick leave 19Æ36 4Æ20 0Æ52 0Æ000

Education level

Primary vs. tertiary education 4Æ60 3Æ46 0Æ12 0Æ187

Secondary vs. tertiary education 2Æ65 4Æ33 0Æ07 0Æ542

Age 0Æ03 0Æ12 0Æ02 0Æ820

Gender (male = 0, female = 1) �1Æ98 3Æ00 �0Æ05 0Æ510

Adjusted R2 0Æ54

B, unstandardised partial regression coefficient; SE, standard error; b, standardised partial

regression coefficient; IBDQ, Inflammatory Bowel Disease Questionnaire; SF-36, Short Form-36.

Y Zhou et al.


produced similar results; those who continued to work had

an average SF-36 score of 16Æ30 higher than those on long-

term sick leave (p < 0Æ01) and those who alternated between

work and sick leave had an average SF-36 score of 19Æ36

higher than those on long-term sick leave (p < 0Æ01).

Discussion

There are many studies examining HRQoL in IBD patients

worldwide but there are limited data available in the Chinese

population. The prevalence of IBD in China is believed to be

low but has been increasing in recent decades (Jiang & Cui

2002). In addition, most previous studies have used either

general or disease-specific indices for comparing UC with CD

or for determining changes over time such as before and after

surgery. In the present study, we applied both generic and

disease-specific measures in parallel. One advantage of using

a generic measure is the possibility of making a comparison

with a general population or across several disease states.

Also, previous studies have observed that generic and disease-

specific measures of quality of life appear to be complemen-

tary rather than interchangeable (Guyatt et al. 1989, McColl

et al. 2004).

Using a consecutive hospital-based sample of IBD patients

with a high response rate, the results of the present study, in

accordance with previous research (Casellas et al. 2002,

2005, Pallis et al. 2002, Blanco et al. 2005, Graff et al.

2006), confirmed that the HRQoL of UC patients is not

statistically significantly different compared to CD patients,

which suggests that disease type is not a key determinant of

HRQoL in IBD. This is inconsistent with some other findings

that have indicated that compared to UC, CD patients have a

worse HRQoL (Drossman et al. 1991, Farmer et al. 1992).

However, the difference in HRQoL observed between UC

and CD are most likely caused by differences in disease

severity (Lopez-Vivancos et al. 1999a, Guthrie et al. 2002).

After adjusting for the disease severity in those studies, the

differences by disease type were no longer significant. We

consider that this finding in our study may also relate to the

fact that our sample was composed of mostly outpatients and

many may either have been in remission or suffering only

mild symptoms. However, as the literature shows, IBD

patients in China were generally less severe and had fewer

complications than in Western countries (APDW 2004

Chinese IBD Working Group 2006, Chinese IBD Working

Group 2006).

In this study, the IBDQ dimensional scores were high; the

mean IBDQ total score was 177Æ0, showing that our sample

of IBD patients had a relatively good quality of life. Our

study results are similar to those of Kim et al. (1999), while

de Boer et al. (1995) and Hashimoto et al. (2003) found

significantly lower scores. Different populations, culturally

diverse attitudes and priorities and severity of disease could

account for this discrepancy.

This study also demonstrated that the HRQoL of active

IBD patients was significantly worse compared to the

HRQoL of remission patients, an observation noted in many

other studies (Casellas et al. 2001, 2002, Guthrie et al. 2002,

Andersson et al. 2003 Bernklev et al. 2005a, 2006). This

confirms the view that HRQoL can be much improved when

disease status shifts from active to remission. For both active

and remission IBD patients, the most pronounced differences

were found in the dimensions of RP and GH compared to the

population norm. This indicates that even remission patients

may still have some practical problems caused by physical

health in their daily lives and that they have a low perception

of their own general health. The fact that RP and GH were

scored lower for those in remission than the population norm

also suggests that the SF-36 is sensitive in detecting HRQoL

change in chronic diseases, even when the diseases are

medically controlled (Andersson et al. 2003).

Interestingly, patients in remission scored higher than the

population norm on the PF, MH and VT dimensions of the

SF-36. This may indicate that chronically ill patients make

certain mental adjustments and have lower quality of life

expectations (Wang et al. 2001). In addition, according to the

studies by Li et al. (2003) and Wang et al. (2001), the norms

of MH and VT are much lower for the Chinese population

compared with the USA, and this may also have contributed

to our findings. For practical reasons, we used the figures from

a historical population norm as a basis for comparison. While

the gender distribution was similar across active, remission

and norm groups, the mean age in the remission group was

8Æ6 years younger than the norm group. Also, there were no

details regarding socioeconomic data. We acknowledge that

there might be other potential confounding factors in the

comparison and further studies using an age-matched, gender-

matched as well as socio-economic status-matched population

might provide more information on these issues.

Although several studies have been undertaken in this area,

there is no clear agreement over which variables have a

greater impact on the HRQoL in IBD patients. Using

multivariate linear regression modelling, two regression

analyses showed that both IBDQ and SF-36 measures

produced similar results and that disease activity is one of

the important factors in terms of the impact on HRQoL. The

HRQoL worsens during relapses, which underlines the need

to use all available measures, medical and/or surgical, to

bring these patients into clinical remission. Other studies

(Bernklev et al. 2005a, Han et al. 2005) used the SF-36 and/



or IBDQ measures to evaluate UC and/or CD patients and

found that HRQoL was closely related to current symptoms,

especially the number of symptoms, with increasing symp-

toms related to a significant reduction in HRQoL. Many

other studies have also produced similar findings (Casellas

et al. 2001, 2002, 2005, Guthrie et al. 2002, Graff et al.

2006, Pizzi et al. 2006, Gibson et al. 2007).

In the present study, we showed that employment status

has a significant influence on patients’ HRQoL, with those

continuing to work or alternating between work and sick

leave positively related to the HRQoL compared to those on

long-term sick leave. It is reasonable to assume that those

who continue to work may have a relatively mild disease and

that their life and work are less limited. This indicates that

HRQoL is influenced not only directly by disease severity, but

also indirectly by participation in the workforce. Unemploy-

ment and sick leave are related to patient’s HRQoL in a

negative way. Other research has also demonstrated this

factor (Bernklev et al. 2006).

A gender gap in HRQoL has also been reported in Western

countries whereby females demonstrate lower HRQoL scores

than those in males (Blondel-Kucharski et al. 2001, Casellas

et al. 2002, 2005, Blanco et al. 2005). In the present study,

there was no difference on HRQoL scores between genders,

and more recent studies are consistent with our results

(Andersson et al. 2003, Zahn et al. 2006, Gibson et al.

2007). We speculate that the use of multiple regression

analysis based on univariate analysis results (Casellas et al.

2002, Blanco et al. 2005), a large sample size (Casellas et al.

2005) or a different population might have contributed to

this difference. However, the effect of gender in predicating

HRQoL remains controversial.

In our study, age had no apparent influence on HRQoL.

While some studies have suggested that older age is associ-

ated with a worse HRQoL (Canavan et al. 2006), others have

indicated that age is not an independent factor in predicting

HRQoL in IBD patients (Andersson et al. 2003, Blanco et al.

2005, Zahn et al. 2006, Gibson et al. 2007). The lower

HRQoL observed in some studies may relate to the preva-

lence of comorbid medical conditions in some segments of the

older population or in those with diminished social function.

In the present study, the influence of educational level was

found not to be significant. However, other studies have

shown that education was associated with perception of

HRQoL in these patients (Irvine et al. 1998, Casellas et al.

2002, Hjortswang et al. 2003). This may be because of

different patient populations, and our relatively small sample

size warrants further evaluation in future studies.

As to the representativeness of the sample, this study used a

consecutive sampling which was representative of the IBD

population of the study site. The high response rate also

strengthened the validity of the data. It is also worth noting

that in China, approximately only one-third of the popula-

tion has health insurance, and the coverage is particularly an

issue for those living in rural areas. Aware that health care is

poorer in quality in rural areas, rural residents with serious

illnesses frequently bypass local practitioners and facilities to

seek care in the urban hospitals (Blumenthal & Hsiao 2005).

We acknowledge that the way health care is financed could

also influence the representativeness of our sample in terms of

overall IBD population.

Several limitations of this study are acknowledged. First,

the research was conducted in one hospital only, the sample

size was not large, and the generalisation of results may be

limited. Further studies are needed to increase the sample size

and geographic representativeness to enhance generalisabil-

ity. Second, the use of a historical population norm might

have influenced our results. Further less confounded com-

parisons such as an age-matched, gender-matched and socio-

economic status-matched control are recommended. Finally,

the cross-sectional design of this study implies that no cause–

effect conclusions can be drawn from the findings. Despite

the limitations, this study has provided some preliminary

insight into HRQoL of IBD patients in China. While the

patients were representative of a particular hospital in

Zhejiang Province, the results may offer some understanding

of HRQoL in IBD patients throughout Mainland China. In

addition, this study will stimulate further research in the area

in different parts of China.

In conclusion, our research has shown that IBD has a

negative influence on Chinese patients’ HRQoL. Disease

activity index and employment status are the strongest

determinants of this HRQoL and should be adjusted for

when examining other factors. We should attempt to improve

the HRQoL of these patients using aggressive medical and/or

surgical therapies. Allowing patients to return to their usual

work position whenever possible may also decrease the

disease impact on their daily lives.

Relevance to clinical practice

The results suggest that any interventions that produce a

stable clinical remission, whether medical or surgical, allow-

ing patients to return to their usual work position can

decrease the disease impact on their daily lives.

Contributions

Study design: YX, WH, DG; data collection and analysis:

YX, WH, DG and manuscript preparation: YX, EJ, DG.

Y Zhou et al.


Conflict of interest

No potential conflict of interests is disclosed by the authors.

References

Andersson P, Olaison G, Bendtsen P, Myrelid P & Sjodahl R (2003)

Health related quality of life in Crohn’s proctocolitis does not

differ from a general population when in remission. Colorectal

Disease 5, 56–62.

APDW 2004 Chinese IBD Working Group (2006) Retrospective

analysis of 515 cases of Crohn’s disease hospitalization in China:

nationwide study from 1990 to 2003. Journal of Gastroenterology

and Hepatology 21, 1009–1015.

Bernklev T, Moum B & Moum T (2002) Quality of life in patients

with inflammatory bowel disease: translation, data quality, scaling

assumptions, validity, reliability and sensitivity to change of the

Norwegian version of IBDQ. Scandinavian Journal of Gastroen-

terology 37, 1164–1174.

Bernklev T, Jahnsen J, Lygren I, Henriksen M, Vatn M & Moum B

(2005a) Health-related quality of life in patients with inflamma-

tory bowel disease measured with the short form-36: psychometric

assessments and a comparison with general population norms.

Inflammatory Bowel Diseases 11, 909–918.

Bernklev T, Jahnsen J, Schulz T, Sauar J, Lygren I, Henriksen M,

Stray N, Kjellevold R, Aadland E & Vatn M (2005b) Course of

disease, drug treatment and health-related quality of life in patients

with inflammatory bowel disease 5 years after initial diagnosis.

European Journal of Gastroenterology & Hepatology 17, 1037–

1045.

Bernklev T, Jahnsen J, Henriksen M, Lygren I, Aadland E, Sauar J,

Schulz T, Stray N, Vatn M & Moum B (2006) Relationship

between sick leave, unemployment, disability and health-related

quality of life in patients with inflammatory bowel disease.


Blanco BL, Moreno-Jimenez B, Mugica JMD & Munoz AR (2005)

Relationship between socio-demographic and clinical variables and

health-related quality of life in patients with inflammatory bowel

disease. Revista Espanola DE Enfermedades Digestivas 97, 887–

898.

Blondel-Kucharski F, Chircop C, Marquis P, Cortot A, Baron F,

Gendre JP & Colombel JF (2001) Health-related quality of life in

Crohn’s disease: a prospective longitudinal study in 231 patients.

American Journal of Gastroenterology 96, 2915–2920.

Blumenthal D & Hsiao W (2005) Privatization and its discontents –

the evolving Chinese health care system. The New England Journal

of Medicine 353, 1165–1170.

de Boer A, Wijker W, Bartelsman JFW & de Haes H (1995)

Inflammatory Bowel Disease Questionnaire: cross-cultural adap-

tation and further validation. European Journal of Gastroenterol-

ogy & Hepatology 7, 1043–1050.

Canavan C, Abrams KR, Hawthorne B, Drossman D & Mayberry JF

(2006) Long-term prognosis in Crohn’s disease: factors that affect

quality of life. Alimentary Pharmacology & Therapeutics 23, 377–

385.

Carter MJ, Lobo AJ & Travis SPL (2004) Guidelines for the man-

agement of inflammatory bowel disease in adults. Gut 53(Suppl.

5), V1–V16.

Casellas F, Lopez-Vivancos J, Badia X, Vilaseca J & Malagelada JR

(2001) Influence of inflammatory bowel disease on different

dimensions of quality of life. European Journal of Gastroenterol-

ogy & Hepatology 13, 567–572.

Casellas F, Lopez-Vivancos J, Casado A & Malagelada JR (2002)

Factors affecting health related quality of life of patients with

inflammatory bowel disease. Quality of Life Research 11, 775–

781.

Casellas F, Arenas JI, Baudet JS, Fabregas S, Garcia N, Gelabert J,

Medina C, Ochotorena I, Papo M & Rodrigo L (2005) Impairment

of health-related quality of life in patients with inflammatory

bowel disease: a Spanish multicenter study. Inflammatory Bowel

Diseases 11, 488–496.

Cheung W, Garratt AM, Russell IT & Williams JG (2000) The UK

IBDQ-A British version of the inflammatory bowel disease ques-

tionnaire development and validation. Journal of Clinical Epide-

miology 53, 297–306.

Chinese IBD Working Group (2006) Retrospective analysis of 3100

cases of ulcerative colitis hospitalization in China. Chinese Journal

of Digestion 26, 368–372.

Drossman DA, Leserman J, Mitchell CM, Li Z, Zagami EA & Pat-

rick DL (1991) Health status and health care use in persons with

inflammatory bowel disease: a national sample. Digestive Diseases

and Sciences 36, 1746–1755.

Farmer RG, Easley KA & Farmer JM (1992) Quality of life assess-

ment by patients with inflammatory bowel disease. Cleveland

Clinic Journal of Medicine 59, 35–42.

Fiocchi C (1998) Inflammatory bowel disease: etiology and patho-

genesis. Gastroenterology 115, 182–205.

Gibson PR, Weston AR, Shann A, Florin THJ, Lawrance IC, Macrae

FA & Radford-Smith G (2007) Relationship between disease

severity, quality of life and health-care resource use in a cross-

section of Australian patients with Crohn’s disease. Journal of

Gastroenterology and Hepatology 22, 1306–1312.

Graff LA, Walker JR, Lix L, Clara I, Rawsthorne P, Rogala L, Miller

N, Jakul L, McPhail C & Ediger J (2006) The relationship of

inflammatory bowel disease type and activity to psychological

functioning and quality of life. Clinical Gastroenterology and

Hepatology 4, 1491–1501.

Guthrie E, Jackson J, Shaffer J, Thompson D, Tomenson B & Creed

F (2002) Psychological disorder and severity of inflammatory

bowel disease predict health-related quality of life in ulcerative

colitis and Crohn’s disease. American Journal of Gastroenterology

97, 1994–1999.

Guyatt G, Mitchell A, Irvine EJ, Singer J, Williams N, Goodacre R &

Tompkins C (1989) A new measure of health status for clinical

trials in inflammatory bowel disease. Gastroenterology 96, 804–

810.

Han SW, McColl E, Steen N, Barton JR & Welfare MR (1998) The

Inflammatory Bowel Disease Questionnaire: a valid and reliable

measure in ulcerative colitis patients in the north east of England.

Scandinavian Journal of Gastroenterology 33, 961–966.

Han SW, McColl E, Barton JR, James P, Steen IN & Welfare MR

(2005) Predictors of quality of life in ulcerative colitis: the

importance of symptoms and illness representations. Inflammatory

Bowel Diseases 11, 24–34.

Harvey RF & Bradshaw JM (1980) A simple index of Crohn’s disease

activity. Lancet 1, 514.



Hashimoto H, Green J, Iwao Y, Sakurai T, Hibi T & Fukuhara S

(2003) Reliability, validity and responsiveness of the Japanese

version of the Inflammatory Bowel Disease Questionnaire. Journal

of Gastroenterology 38, 1138–1143.

Hendriksen C & Binder V (1980) Social prognosis in patients with

ulcerative colitis. British Medical Journal 281, 581–583.

Hjortswang H, Jarnerot G, Curman B, Sandberg-Gertzen H, Tysk C,

Blomberg B, Almer S & Strom M (2001) Validation of the

Inflammatory Bowel Disease Questionnaire in Swedish patients

with ulcerative colitis. Scandinavian Journal of Gastroenterology

36, 77–85.

Hjortswang H, Jarnerot G, Curman B, Sandberg-Gertzen H, Tysk C,

Blomberg B, Almer S & Strom M (2003) The influence of demo-

graphic and disease-related factors on health-related quality of life

in patients with ulcerative colitis. European Journal of Gastroen-

terology & Hepatology 15, 1011–1020.

Hu RW, Ouyang Q, Chen X, Chang YY, Bai AP, Wang RH & Zhang

H (2007) Analysis of the articles of inflammatory bowel disease in

the literature of China in recent fifteen years. Chinese Journal of

Gastroenterology 12, 74–77.

Irvine EJ (2008) Quality of life of patients with ulcerative colitis:

past, present and future. Inflammatory Bowel Diseases 14, 554–

565.

Irvine EJ, Feagan B, Rochon J, Archambault A, Fedorak RN, Groll A,

Kinnear D, Saibil F & McDonald JW (1994) 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 106, 287–296.

Irvine EJ, Grace E, Kerr GD, Lyrenas E, Bolin T & Omorain C

(1998) Non-disease related factors affecting health related quality

of life (HRQOL) in inflammatory bowel disease (IBD). Gastro-

enterology 114, A1002.

Jiang XL & Cui HF (2002) An analysis of 10218 ulcerative colitis

cases in China. World Journal of Gastroenterology 8, 158–161.

Kim WH, Cho YS, Yoo HM, Park IS, Park EC & Lim JG (1999)

Quality of life in Korean patients with inflammatory bowel dis-

eases: ulcerative colitis, Crohn’s disease and intestinal Behcet’s

disease. International Journal of Colorectal Disease 14, 52–57.

Lennard-Jones JE (1989) Classification of inflammatory bowel dis-

ease. Scandinavian Journal of Gastroenterology 24, 2–6.

Leong RW, Lee YT, Ching JY & Sung JJ (2003) Quality of life in

Chinese patients with inflammatory bowel disease: validation of

the Chinese translation of the Inflammatory Bowel Disease Ques-

tionnaire. Alimentary Pharmacology & Therapeutics 17, 711–718.

Li L, Wang HM & Shen Y (2003) Chinese SF-36 health survey:

translation, cultural adaptation, validation and normalisation.

Journal of Epidemiology and Community Health 57, 259–263.

Lopez-Vivancos J, Casellas F, Badia X, Vilaseca J & Malagelada JR

(1999a) Different perception of health related quality of life in

ulcerative colitis vs. Crohn’s disease. Gastroenterology 116, A765.

Lopez-Vivancos J, Casellas F, Badia X, Vilaseca J & Malagelada JR

(1999b) Validation of the Spanish version of the Inflammatory

Bowel Disease Questionnaire on ulcerative colitis and Crohn’s

disease. Digestion 60, 274–280.

McColl E, Han SW, Barton JR & Welfare MR (2004) A comparison

of the discriminatory power of the Inflammatory Bowel Disease

Questionnaire and the SF-36 in people with ulcerative colitis.

Quality of Life Research 13, 805–811.

Ouyang Q, Tandon R, Goh KL, Ooi CJ, Ogata H & Fiocchi C (2005)

The emergence of inflammatory bowel disease in the Asian Pacific

region. Current Opinion in Gastroenterology 21, 408–413.

Pallis AG, Vlachonikolis IG & Mouzas IA (2001) Quality of life of

Greek patients with inflammatory bowel disease: validation of the

Greek translation of the Inflammatory Bowel Disease Question-

naire. Digestion 63, 240–246.

Pallis AG, Vlachonikolis IG & Mouzas IA (2002) Assessing health-

related quality of life in patients with inflammatory bowel disease,

in Crete, Greece. Available at: http://www.biomedcentral.com/

1471-230X/2/1 (accessed 12 May 2008).

Pizzi LT, Weston CM, Goldfarb NI, Moretti D, Cobb N, Howell JB,

Infantolino A, Dimarino AJ & Cohen S (2006) Impact of chronic

conditions on quality of life in patients with inflammatory bowel

disease. Inflammatory Bowel Diseases 12, 47–52.

Ren WH, Lai M, Chen Y, Irvine EJ & Zhou YX (2007) Validation of

the mainland Chinese version of the Inflammatory Bowel Disease

Questionnaire (IBDQ) for ulcerative colitis and Crohn’s disease.


Russel MG, Pastoor CJ, Brandon S, Rijken J, Engels LG, van der

Heijde DM & Stockbrugger RW (1997) Validation of the Dutch

translation of the Inflammatory Bowel Disease Questionnaire

(IBDQ): a health-related quality of life questionnaire in inflam-

matory bowel disease. Digestion 58, 282–288.

Si JM, Chen SJ & Sun LM (2003) An epidemiological and quality of

life study of irritable bowel syndrome in Zhejiang province.

Chinese Journal of Internal Medicine 42, 34–37.

Walmsley RS, Ayres RCS, Pounder RE & Allan RN (1998) A simple

clinical colitis activity index. British Medical Journal 43, 29–32.

Wan CH, Fang JQ, Shi ML, Chen LY & Zhang YZ (1998) A com-

parative study on measuring quality of life for drug addicts by SF-36

scales. Chinese Journal of Behavioral Medical Science 7, 260–262.

Wang HM, Li L & Shen Y (2001) The investigation of quality of life

in a population in Hangzhou using the Chinese version of the

SF-36 Health Survey. Chinese Journal of Preventive Medicine

35, 428–430.

Wang YF, Zhang H & Ouyang Q (2007) The clinical characteristic

differences of inflammatory bowel disease in China and western

countries. Chinese Journal of Gastroenterology 12, 124–128.

Xiong LS, Chen MH, Wang WA, Chen HX, Xu AG & Hu PJ (2004)

Evaluation of the quality of life of patients with irritable bowel

syndrome. Chinese Journal of Internal Medicine 43, 356–359.

Zahn A, Hinz U, Karner M, Ehehalt R & Stremmel W (2006) Health-

related quality of life correlates with clinical and endoscopic

activity indexes but not with demographic features in patients with

ulcerative colitis. Inflammatory Bowel Diseases 12, 1058–1067.

Y Zhou et al.


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Assessing health-related quality of life in patients with inflammatory bowel disease in Zhejiang, China