Fatigue in rheumatoid arthritis - Universiteit Twente

224 Pages·2012·0.95 MB·English

Fatigue in rheumatoid arthritis:
from patient experience to measurement

Stephanie Nikolaus
Thesis, University of Twente, 2012
ISBN/EAN 9789461082763
© Stephanie Nikolaus

Lay-out and printed by Gildeprint Drukkerijen, Enschede, the Netherlands

The studies presented in this thesis were performed at the department of Psychology,
Health & Technology of the University of Twente (Enschede) and the Arthritis Center
Twente at Medisch Spectrum Twente hospital (Enschede) and the hospitals of
“Ziekenhuisgroep Twente” (Almelo and Hengelo), the Netherlands. The rheumatology
research program of PHT is financially supported by the Dutch Arthritis Foundation
(Reumafonds).
This project is financially supported by Stichting Reumaonderzoek Twente and the
Institute of Behavioural Research.
Publication of this thesis was financially supported by the Dutch Arthritis Foundation
(Reumafonds).
FATIGUE IN RHEUMATOID ARTHRITIS:
FROM PATIENT EXPERIENCE TO MEASUREMENT

PROEFSCHRIFT

ter verkrijging van
de graad van doctor aan de Universiteit Twente,
op gezag van de rector magnificus,
prof.dr. H. Brinksma,
volgens besluit van het College voor Promoties
in het openbaar te verdedigen
op vrijdag 16 maart 2012 om 14.45 uur

door

Stephanie Nikolaus
geboren op 2 november 1980
te Kleef, Duitsland
Dit proefschrift is goedgekeurd door de promotor Prof. dr. M.A.F.J. van de Laar en
assistent-promotoren Dr. C. Bode en Dr. E. Taal.
Samenstelling promotiecommissie:

Promotor: Prof. dr. M.A.F.J. van de Laar

Assistent-promotoren: Dr. C. Bode
Dr. E. Taal

Leden: Prof. dr. E.T. Bohlmeijer (University of Twente)
Prof. dr. J. Dekker (Free University Amsterdam)
Prof. dr. R. Geenen (University Utrecht)
Prof. dr. C.A.W. Glas (University of Twente)
Prof. dr. S. Hewlett (University of West England, Bristol UK)
Prof. dr. P.L.C.M. van Riel (Radboud University, Nijmegen)

Contents

Chapter 1 General introduction 9

Chapter 2 Fatigue and factors related to fatigue in rheumatoid
arthritis: a systematic review 21

Chapter 3 Measuring fatigue in rheumatoid arthritis 69

Chapter 4 New insights into the experience of fatigue among
patients with rheumatoid arthritis: a qualitative study 75

Chapter 5 Four different patterns of fatigue in rheumatoid
arthritis patients: results of a Q-sort study 89

Chapter 6 Selection of items for a computer-adaptive test to
measure fatigue in patients with rheumatoid
arthritis: a Delphi approach 115

Chapter 7 Which dimensions of fatigue should be measured in
patients with rheumatoid arthritis? A Delphi study 137

Chapter 8 Expert’s evaluations of fatigue questionnaires used in
rheumatoid arthritis – A Delphi study among patients,
nurses and rheumatologists in the Netherlands 149

Chapter 9 Calibration of a multidimensional item bank to measure
fatigue in rheumatoid arthritis patients 163

Chapter 10 Summary and general discussion 197

Summary in Dutch (Samenvatting) 207
Acknowledgements (Dankwoord) 215
Curriculum vitae 219
List of publications 221

Chapter 1

General introduction

9
When you enter the term “human fatigue” into Google approximately 131.000.000 hits
emerge within 0.17 seconds. This enormous amount of information indicates that fatigue
is a topic that has considerable relevance for people. Basically, being tired is nothing to
worry about. Everybody knows it as signal that body and mind need sleep or relaxation for
recovery. Usually fatigue diminishes after taking adequate rest, body and mind are
refreshed again. The Oxford dictionary defines fatigue as “a feeling of being extremely
tired, usually because of hard work or exercise”.1 However, for most persons with a
chronic somatic condition such as rheumatoid arthritis (RA), the situation is different.

Aim of this thesis was to explore how fatigue is experienced in patients with RA as only
very little is known about this phenomenon. Furthermore it was investigated how fatigue
in RA can be measured adequately. The topic is thus twofold; meaning and measurement
of fatigue in RA.

Rheumatoid arthritis and the experience of fatigue
RA is a chronic auto-immune disease that is characterized by inflammation of the joints.2
Typical symptoms are pain, tender and swollen joints, stiffness, functional limitations and
fatigue. Between 40% and 80% of the patients report substantial fatigue.3-8 In fact, they
mention fatigue as one of their most bothersome problems with RA.9 Patients describe
their fatigue as annoying, multidimensional symptom with far-reaching consequences for
daily life.10-13 It is different from usual fatigue or tiredness because it is more extreme and
no longer earned what makes it unpredictable. Thus general descriptions and lay
knowledge do not reflect the experience of patients with RA. Consequently, a different
definition of fatigue is needed than for healthy people. However, an internationally
accepted definition of fatigue in RA does not exist.14 We do not yet know for sure whether
there are differences between RA fatigue and fatigue in other somatic diseases. According
to Hewlett there are similar multidimensional components and consequences of fatigue
but the diseases differ significantly with regard to the attribution and interpretation of
fatigue.11 In cancer for example, fatigue is attributed to chemotherapy and therefore can
be predicted and prepared for.15 In MS, fatigue is perceived as exacerbating existing
symptoms, whereas in RA existing symptoms are perceived to exacerbate fatigue.16 Based
on these differences we might conclude that a definition of fatigue in RA seems necessary
and useful.
A definition without referring to previous activity is provided by Dittner et al.17 They state
that fatigue is an essentially subjective experience that can be described as “extreme and
persistent tiredness, weakness or exhaustion—mental, physical or both”.17 In our
10