ARTHRITIS & RHEUMATISM
Vol. 54, No. 10, October 2006, pp 3113–3118
DOI 10.1002/art.22130
© 2006, American College of Rheumatology
Changes in Health Assessment Questionnaire Disability Scores
Over Five Years in Patients with Rheumatoid Arthritis
Compared With the General Population
Tuulikki Sokka,
1
Hannu Kautiainen,
2
Pekka Hannonen,
3
and Theodore Pincus
4
Objective. To analyze longitudinal data over 5
years for changes in Health Assessment Questionnaire
(HAQ) scores in patients with rheumatoid arthritis
(RA) and age- and sex-matched controls from the
general population.
Methods. In 2000 and 2005, identical self-report
questionnaires were mailed to a cohort of patients with
RA and control cohort from the community. The ques-
tionnaire included the HAQ, which was used to assess
functional status. Changes in HAQ scores over 5 years
were analyzed.
Results. In 2000, 73% of 1,495 patients with RA
and 77% of 2,000 general population controls responded
to the questionnaire. In 2005, 84% of 2,022 patients with
RA and 77% of 1,817 controls responded. A total of 863
patients with RA and 1,176 community controls re-
sponded in both 2000 and 2005 and were included in the
analyses. Mean baseline HAQ scores were significantly
higher in patients with RA than in controls (0.71 versus
0.17; P < 0.001). Over 5 years, the HAQ scores in-
creased by 0.01 units per year in both the RA cohort and
the community population; in both cohorts, the net
change was primarily attributable to individuals over
age 70 years. Changes in HAQ scores were similar in
patients and controls who had low HAQ scores at
baseline. Female patients with baseline HAQ scores of
>0.5 had less potential for improvement than did
controls. Among subjects in both groups who had HAQ
scores >2, death was a common outcome over the next
5 years.
Conclusion. Currently, progression of functional
disability among patients with RA and among persons
in the general population is largely explained by the
aging process. Our results showing stable function
scores over 5 years in most patients with RA who are
younger than age 70 years provide further evidence of
improved status of RA patients today compared with the
major declines observed in previous decades.
Functional status is the most significant prognos-
tic measure of long-term outcomes in rheumatoid arthri-
tis (RA), such as work disability (1–3), mortality (4–6),
costs (7), the need for joint replacement surgery (8), and
loss of function (4,9). Furthermore, patients with RA
who have significant functional disability have a 3-fold
increased risk of mortality compared with that in the
general population; this risk is comparable with that in
individuals in the general population in the highest
quintile for systolic and diastolic blood pressure, choles-
terol level, or pack-years of smoking (10). In addition,
improvements in disease activity and Health Assessment
Questionnaire (HAQ) (11) scores in patients with early
RA are associated with favorable long-term outcomes
(12), analogous to improved long-term outcomes
achieved by normalization of blood pressure or serum
cholesterol levels.
The HAQ was developed in the late 1970s to
measure outcomes in patients with arthritis. Reference
values in a normal population were not included in the
initial analysis nor in almost all subsequent analyses.
Such information would appear to be of considerable
interest in view of evidence that poor physical function is
a predictor of mortality in nonrheumatic conditions,
including congestive heart failure (13) and acquired
immunodeficiency syndrome (14,15). In 2004, we re-
Supported by a grant from the Central Finland Health Care
District.
1
Tuulikki Sokka, MD, PhD: Jyva ¨skyla ¨ Central Hospital, Jy-
vaskyla, Finland and Vanderbilt University, Nashville, Tennessee;
2
Hannu Kautiainen, BA: Rheumatism Foundation Hospital, Heinola,
Finland;
3
Pekka Hannonen, MD, PhD: Jyva ¨skyla ¨ Central Hospital,
Jyvaskyla, Finland;
4
Theodore Pincus, MD: Vanderbilt University,
Nashville, Tennessee.
Address correspondence and reprint requests to Tuulikki
Sokka, MD, Arkisto/Tutkijat, Jyva ¨skyla ¨ Central Hospital, 40620 Jyvas-
kyla, Finland. E-mail: tuulikki_sokka@hotmail.com.
Submitted for publication April 13, 2006; accepted in revised
form June 26, 2006.
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