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Revista Española de Enfermedades Digestivas
versión impresa ISSN 1130-0108
Rev. esp. enferm. dig. vol.105 no.3 Madrid mar. 2013
https://dx.doi.org/10.4321/S1130-01082013000300005
Questionnaires for measuring fatigue and its impact on health perception in inflammatory bowel disease
Cuestionarios de medida e impacto de la fatiga en la percepción de salud en la enfermedad inflamatoria intestinal
María Dolores Castillo-Cejas, Virginia Robles, Natalia Borruel, Antonio Torrejón, Ester Navarro, Andrés Peláez and Francesc Casellas
Crohn-Colitis Care Unit (UACC). Gastroenterology Department. Hospital Universitari Vall d'Hebron. Barcelona, Spain
ABSTRACT
Introduction: fatigue impacts perceived health, but its importance in inflammatory bowel disease is not known.
Objectives: to define the applicability of the fatigue measurement questionnaires and analyze it in patients with Crohn's disease and ulcerative colitis.
Material and methods: in a first phase, the psychometric properties of 3 fatigue measurement questionnaires were determined in 99 patients: Daily Fatigue Impact Scale, Fatigue Severity Scale, and Modified Fatigue Impact Scale. In a second phase, fatigue status and its relationship to disease and quality of life was determined in 127 patients and 69 healthy controls.
Results: the first part of the study showed the applicability of the questionnaires listed in inflammatory bowel disease, the Daily Fatigue Impact Scale (DFIS) having the best correlation with the quality of life and clinical activity. In the second phase, significantly higher levels of fatigue were observed in active disease than in disease in remission and healthy controls (p < 0,05). The severity of fatigue was significantly correlated with quality of life (r = -0.66 and -0.72 between IBDQ-9 and DFIS and in Crohn's disease and ulcerative colitis, respectively) and with disease activity (r = 0.25 and Crohn's disease and ulcerative colitis, respectively, p < 0.05).
Conclusions: in inflammatory bowel disease, fatigue measurement questionnaires have good properties and show that fatigue is an important manifestation of the disease, which has a significant impact on quality of life of patients.
Key words: Fatigue. Inflammatory bowel disease. Quality of life. Validation. Questionnaire.
RESUMEN
Introducción: la fatiga repercute en la salud percibida, pero se desconoce su relevancia en la enfermedad inflamatoria intestinal.
Objetivos: definir la aplicabilidad de cuestionarios de medida de fatiga y analizarla en pacientes con enfermedad de Crohn y colitis ulcerosa.
Material y métodos: en una primera fase, en 99 pacientes se determinaron las propiedades psicométricas de 3 cuestionarios de medida de fatiga: Escala del Impacto Diario de Fatiga, Escala de Gravedad de la Fatiga y Escala Modificada del Impacto de Fatiga. En una segunda fase, se determinó el estado de fatiga y su relación con la enfermedad y la calidad de vida en 127 pacientes y 69 controles sanos.
Resultados: la primera parte del estudio, demostró la aplicabilidad de los cuestionarios citados en la enfermedad inflamatoria intestinal, siendo la Escala del Impacto Diario de Fatiga (EIDF) el de mejor correlación con la calidad de vida y la actividad clínica. En la segunda fase, se objetivaron unos niveles significativamente superiores de fatiga en la enfermedad activa que en la enfermedad en remisión y los controles sanos (p < 0,05). La intensidad de la fatiga se correlacionó de forma significativa con la calidad de vida (r = -0,66 y -0,72 entre el IBDQ-9 y EIDF en enfermedad de Crohn y colitis ulcerosa respectivamente) y con la actividad de la enfermedad (r = 0,25 y 0,33 en la enfermedad de Crohn y colitis ulcerosa respectivamente, p < 0,05).
Conclusiones: en la enfermedad inflamatoria intestinal los cuestionarios de medida de fatiga tienen propiedades adecuadas y demuestran que la fatiga es una manifestación importante de la enfermedad, que repercute de forma significativa en la calidad de vida de los pacientes.
Palabras clave: Fatiga. Enfermedad inflamatoria intestinal. Calidad de vida. Validación. Cuestionario.
Introduction
Inflammatory bowel disease (IBD) includes Crohn's disease (CD) and ulcerative colitis (UC). Both are chronic inmunoinflammatory diseases of fluctuating course that are associated with complications, including the risk of neoplastic processes (1). They require continuous treatment, with potential side effects that must be controlled and, eventually, surgery (2,3). IBD limits the quality of life of patients as a result of the events inherent to it, its complications, and their treatments (4,5), and also due to more subjective variables of the patient itself, affecting all domains of life (6-8).
Assessment of quality of life in relation to health has gained great importance in recent years (9-11). Given its multidimensional nature, its course over time, and its subjectivity, measuring quality of life is complex. Because of this, administration of questionnaires specifically designed for that purpose is used (12).
As in other gastrointestinal chronic intestinal diseases, such as celiac disease (13), fatigue is a manifestation reported by many patients with IBD, deeply influencing their quality of life (14) and representing a major health-determining factor (15-17).
Fatigue is the feeling of tiredness with reduced energy levels, decreased muscle strength, and cognitive impairment. As a symptom, chronic fatigue is that which persists for longer than 6 months, generally associated with a chronic illness and not related to exertion or completely improved with rest (18). It is characterized by its subjective nature and depends on many variables. Several scales have been developed for its measurement (19). However, in our setting, there is no information on the applicability of questionnaires for measuring fatigue in patients with IBD, or the impact of fatigue on quality of life in these patients.
Therefore, the objectives of this study were, on the one hand, to assess in patients with IBD the applicability of the following three questionnaires for measuring fatigue: Daily Fatigue Impact Scale (DFIS), Fatigue Severity Scale (FSS) and Modified Fatigue Impact Scale (MFIS), and to determine which had better application characteristics. On the other hand, to determine the impact of fatigue on health perception in patients with IBD in our setting. A prospective study was thus carried out in two phases in patients with IBD and healthy controls to whom questionnaires on fatigue and quality of life were administered.
Methods
A prospective, observational cross-sectional study was designed in patients with CD and UC, unpreselected, in two phases:
First phase, validation of fatigue measurement questionnaires: Daily Fatigue Impact Scale (DFIS), Fatigue Severity Scale (FSS), and Modified Fatigue Scale (MFIS).
Second phase, administration of the DFIS questionnaire to quantify fatigue in patients with IBD and correlate it with the degree of activity and quality of life status.
Participants
Patients included in the study were from the Crohn-Colitis Care Unit (UACC) of the Hospital Universitari Vall d'Hebron, as well as patients admitted to this hospital for a relapse of their disease. All patients, over 18 years of age, had been previously diagnosed according to standard criteria (clinical, endoscopic and histological) (20,21), had different states of clinical activity and had expressed their consent to participate in the study.
Patients were stratified into 2 groups according to their diagnosis, CD versus UC. Patients with inability to complete the questionnaires, those with an underlying psychiatric illness or with other relevant chronic disease were excluded.
Additionally, a third study group consisting of healthy subjects was included. This control group was used to give meaning to the values of the fatigue questionnaire in patients from the healthy population, given the lack of data on normal values in the reference population. Inclusion criteria for the control group were the absence of disease and age between 18 and 65 years.
Disease activity in participants was measured using standard clinical indexes (22): Colitis Activity Index (CAI) for UC and Harvey-Bradshaw index for CD. Patients were considered in remission if the score was less than 6 and 3, respectively.
Measurement of fatigue
The fatigue questionnaires evaluated to determine applicability in IBD were the DFIS, FSS, and MFIS.
The DFIS is a unidimensional scale containing 8 items with 5 options each, so that the total score ranges from 0 to 32, where a higher score indicates more severe fatigue (23,24).
The FSS has been widely used in its English version and translations into other languages (including Spanish). It has been applied previously to neurological diseases, like multiple sclerosis (25), and other chronic diseases of autoimmune origin (26). The FSS is a multidimensional scale assessing psychosocial and generic aspects. It consists of 9 items with 7 possible values (where 0 indicates "totally disagree", 4 "neither agree nor disagree", and 7 is "totally agree"). The cutoff point is placed at 5 to differentiate between the presence or absence of the symptom.
The MFIS is a multidimensional scale that has been used in other chronic diseases. It has been shown that there are no differences in applying the MFIS between several languages, including Spanish, and different cultures (27). It consists of 21 items distributed into 3 subscales: physical, cognitive, and psychosocial. The final score ranges from 0 and 84, and a score of 38 has been established as the cutoff point to define the presence or absence of fatigue.
Measurement of quality of life
For measurement of health-related quality of life, the generic EuroQol-5D questionnaire and the disease-specific IBDQ-36 and IBDQ-9 questionnaires were used.
The EuroQol-5D is a questionnaire that has been widely validated in different languages and countries, including Spanish, for which normal values have been reported for Spanish and Catalan populations (28,29). It has also been assessed in a wide variety of chronic diseases (30-32) including IBD (4,33,34). It evaluates 5 dimensions of health status which are: Mobility, self-care, daily life activities, pain/discomfort, and anxiety/depression (35,36). Each item has 3 possible answers, where 1 is not having problems with regard to the assessed variable and 3 is having limiting problems. The result is expressed as a tariff ranging from 0 to 1, considering 1 the best possible state and 0 the worst. The EuroQol-5D also includes a visual analog scale (VAS) for quality of life (37). The VAS consists of a 100 mm vertical line, like a thermometer, ranging from 0 (worst imaginable health state) to 100 (best imaginable health state). The individual should mark the point on the vertical line that best reflects, in their opinion, the assessment of their general health status on the day of data collection.
The IBDQ (38,39) is a specific questionnaire for measuring quality of life in patients with IBD. There are different versions of the IBDQ duly translated and validated in Spanish. In the first phase of the study, the 36 item version (40) was used. In the second phase, the unidimensional IBDQ-9 short version with 9 questions was used (41). Each question is answered using a Likert scale from 1 to 7, where 1 represents worst quality of life and 7 the best. The result of the IBDQ-9 is expressed by a score transformed into a percentage on a scale of 0-100, with better health status corresponding to a higher score.
Procedure
Participants of both phases of the study underwent a clinical evaluation related to their disease status (type, activity, manifestations, etc.) and were requested to give consent to participate in the study.
In the first phase of the study, the fatigue measurement questionnaires DFIS, FSS and MFIS and the IBDQ-36 quality of life questionnaire were administered. In the second phase, after clinical classification, the questionnaires DFIS for quantification of fatigue, IBDQ-9 and EuroQol-5D-Tariff and VAS scale were administered.
Statistical analysis
The records with the information on the included cases were managed using an Excel spreadsheet. The statistical data analyses were made using the SigmaStat version 3.5 computer program and SPSS Statistics version 17.0. Since many variables did not follow a normal distribution according to the Kolmogorov test, the results were expressed as medians and percentiles [25-75], and the statistics used were based on nonparametric tests. Quantitative varia-bles were compared using the Mann-Whitney or Kruskal-Wallis statistical tests as required for unpaired samples. A value of p < 0.05 was considered statistically significant.
Results
Questionnaire validation phase
A total of 99 patients were included, 55 with CD and 44 with UC. Both groups had a similar distribution in terms of sex, age, and time since diagnosis. The only differences were related to smoking and the number of prior surgeries (Table I). It was observed that the group of CD patients had a higher percentage of smokers (p < 0.05) as well as a higher proportion of patients with prior surgery compared to UC patients (p < 0.01).
The correlation was then established between the three fatigue questionnaires (Fig. 1), all showing a positive correlation, with values "r" between 0.77 and 0.84, with p < 0.001 in the three cases.
Next, the correlation was established between fatigue measured using the three questionnaires and quality of life measured with the global score of the IBDQ-36. It was observed that the results of the three fatigue questionnaires had an inverse relationship, showing that the greater the fatigue, the poorer the quality of life perceived. A statistically significant correlation of IBDQ-36 with the three fatigue questionnaires was obtained (with a r between -0.72 and -0.81, p < 0.001), and the correlation with the DFIS was slightly higher than with the other two questionnaires (Fig. 2).
The relationship between fatigue and clinical activity of the disease was established by correlation of the three questionnaires (DFIS, FSS, and MFIS) with the score on the Harvey-Bradshaw index in patients with CD and the score on the CAI in patients with UC. The results obtained showed a positive relationship between the degree of disease activity and the level of fatigue in the three questionnaires tested, with the greater the fatigue the greater the clinical activity. The questionnaire with greatest potency in this relationship, both in UC and CD patients, was the DFIS. It obtained r = 0.67 (p < 0.001) for CD and r = 0.50 (p < 0.001) for UC with the FSS. These values were r = 0.53 (p < 0.001) for CD and r = 0.37 (p < 0.05) for UC; with the MFIS, the values were r = 0.48 (p < 0.001) for CD and r = 0.39 (p < 0.01) for UC.
Based on the results described above, we consider that the three fatigue measurement questionnaires tested in IBD were valid, but the DFIS was chosen for the next phase of the study because it showed the greatest correlation with clinical activity and quality of life of patients.
Questionnaire administration phase
A total of 137 patients were included in this phase, 70 with a diagnosis of CD, and 67 with a diagnosis of UC, different from the validation phase. Overall data are shown in Table II, suggesting that UC patients had lower tobacco consumption and a higher median age than CD patients, reaching a p value with statistical significance. Another difference was that there was a higher percentage of smokers among patients with CD. Regarding clinical characteristics, CD patients had been diagnosed younger than the UC patients, and had required a higher percentage of surgery, 50 % in CD patients versus 3 % in UC patients (p < 0.05). It was also found that there was a higher percentage of patients in relapse in the CD group (24.3 %) than in the UC group. At the time of data collection, a follow-up laboratory test was obtained to determine the presence of anemia, vitamin B12 deficiency and acute phase reactants. These parameters were also analyzed according to whether patients were in relapse or remission, revealing (Table III) that patients in relapse had elevated acute phase reactants (leukocyte count, platelet count, and CRP, p < 0.001) to a greater extent than patients in remission. Moreover, they had lower hemoglobin values (median 13.3 g/dl in patients in remission and 12.6 g/dl in patients in relapse) (p < 0.05), with no differences between the CD group and UC group.
Measurement of fatigue was performed according to the DFIS questionnaire and quality of life according to the EuroQol-5D and IBDQ-9 questionnaires. No statistically significant differences were observed between CD and UC patients in scores on the three questionnaires. However, there was a certain trend to score worse on the DFIS in patients with CD than in those with UC (median 9.5 vs. 6.0, respectively), although without reaching statistical significance.
Analysis was then performed by stratifying patients according to the degree of disease activity. It was found that patients in relapse scored worse on the quality of life questionnaires, both IBDQ-9 and EuroQol-5D, and had a greater fatigue index on the DFIS questionnaire, with no differences between CD and UC (Table IV).
The relationship between clinical disease activity and level of fatigue, on the one hand, and quality of life and level of fatigue on the other, was statistically significant in both cases (Fig. 3). The correlation of clinical activity with fatigue was r = 0.34 and r = 0.26 in UC and CD, respectively (p < 0.01). Similarly, the correlation of clinical activity with quality of life was also statistically significant in UC and CD (r = -0.62 and r = -0.47, respectively, p < 0.001 (Fig. 4). Also, when establishing the correlation between the degree of fatigue and quality of life, values of inverse correlation were obtained reaching statistical significance (r = -0.73 and r = -0.67 for UC and CD, respectively, p < 0.001) (Fig. 5).
As mentioned above, given the lack of normal ranges in our population, a control group of healthy individuals was established to determine the degree of perception of fatigue in people without disease. A total of 69 people were included. The demographic data are shown in Table II, with no statistically significant differences versus the group of patients.
Comparison of the DFIS score in the group of healthy individuals versus the group of patients, overall and by patients in relapse or in remission, showed that healthy controls had a lower level of fatigue compared to patients (4.0 vs. 9.0, respectively, p < 0.01). According to the stratification of patients by disease activity, a poorer DFIS score was seen in both groups of patients compared to controls (Table V).
Discussion
Little information is available on the impact of fatigue or its impact on quality of life in patients with IBD. Therefore this study was designed in two sequential stages with two concrete objectives. The first objective was to establish whether fatigue measurement questionnaires available in Spanish -DFIS, FSS, and MFIS- were applicable to patients with IBD. The second objective of the study was to analyze fatigue in IBD by administering the questionnaire with the best properties, and determining its influence on the quality of life of patients. Lastly, the importance of fatigue in IBD was established by comparing the results obtained in patients with those of a control group of healthy subjects.
The results obtained in the study show that the three fatigue measurement questionnaires analyzed have adequate properties for use in IBD, with the DFIS standing out as the one which achieves better correlations with clinical activity and quality of life of the patients. Our results also suggest that fatigue is a major problem in IBD, both in CD and UC, and is influenced by various factors, particularly disease activity. In addition, fatigue impacts unfavorably on patient quality of life, in both CD and UC, so that greater fatigue is related to poorer quality of life.
Both CD and UC patient groups had similar demographic characteristics, as well as a similar disease course, except for the greater need for surgery in patients with CD. Laboratory parameters of both groups also showed significant differences, except for higher acute phase reactants in patients in relapse (CD or UC) than in those in remission.
Previously, the study by Jelsness et al. (42) had shown in a Norwegian population that the greater the fatigue, the poorer IBD patients scored on quality of life tests, both in CD and UC, particularly in the domains of physical function, which caused them to have problems to comply with their work/studies. They also found that having chronic fatigue as a symptom caused patients to have a greater degree of concern about their disease, which in turn led to poorer, perceived quality of life. In our study, a similar score was found in the quality of life questionnaires between CD and UC groups, measured both with generic instruments and specific for IBD. When fatigue was quantified, no statistically significant differences were observed between both groups, although a clear trend was shown to score worse, that is, express greater fatigue, in the CD group. This could be related to the higher percentage of patients in relapse of the disease in the group of CD patients compared to the percentage of patients in relapse in the group of UC patients. Quality of life and the fatigue index showed an inversely proportional relationship, with a statistically significant index of relation demonstrating that more fatigue is associated with poorer quality of life. The Kruskal-Wallis statistical analysis confirmed fatigue as a determinant of poor quality of life, which was observed in both CD and UC.
Another of our objectives in the study was to establish whether the disease activity index is related to fatigue. Römkens et al. (43) evaluated a group of Dutch patients with IBD and showed that patients reporting more fatigue were those with greatest activity. Our patients were stratified between high activity index (considered as relapse) and low activity index (considered as remission) and poorer perceived quality of life was found in patients in relapse with statistically significant differences, both in patients with CD and UC. When the relationship was established between quality of life and clinical disease activity, an inverse trend was seen between both parameters so that the greater the activity, the poorer perceived quality of life, with statistical significance. This same relationship was also found between the activity index and patient fatigue, in such a way that patients with a greater activity index expressed more fatigue. In this study, the influence of other factors on fatigue was not determined, an aspect that remains open for future projects.
In our study, the fatigue index obtained in patients with IBD was compared with a healthy control group, and the patients in general had a greater DFIS index than the healthy subjects, which is in line with the results of the study conducted by Römkens et al. (43). On stratifying patients in relapse and remission, it was seen that patients in remission also scored poorer than healthy subjects, with the difference reaching statistical significance.
This study has the limitations of the small number of patients included, which prevented performing subanalyses of groups to compare patients according to their extradigestive manifestations, extension of disease and other related aspects. This study could be expanded in the future, which would also allow for other factors to be establis-hed which influence the perception of fatigue by patients regardless of the underlying disease.
In conclusion, from this study it can be stated that in inflammatory bowel disease, both CD and UC, fatigue measurement questionnaires, particularly the DFIS, have properties which make their use appropriate. It has also been confirmed in our setting that fatigue is an important manifestation of the disease, particularly in relapse, and significantly impacts the quality of life of patients.
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Correspondence:
Francesc Casellas
Unitat d'Atenció Crohn-Colitis
Hospital Universitari Vall d'Hebron
Pso. Vall d'Hebron, 119
08035 Barcelona, Spain
e-mail: fcasellas@vhebron.net
Received: 08-10-2012
Accepted: 17-01-2013