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The work dynamics of the person with rheumatoid arthritis.

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This paper traces the work history of patients
with rheumatoid arthritis (RA) from the year of diagnosis to 1985. The paper also describes the risk factors
for work loss among patients with RA. It uses data from
a panel of 698 RA patients, observed for 4 years, from
the practices of a random sample of northern California
rheumatologists. Of these 698, 353 had worked for pay
at some point in their lives. Three hundred six of the 353
had worked when diagnosed as having RA. Of these
306, 157 (51%) were no longer working in 1985. Fortyseven individuals started working after the onset of
illness, but of these, approximately one-third had
stopped working by 1985. In all, 50% of RA patients
with some work experience stopped working within a
decade of diagnosis, 60% within 15 years, and 90%
within 30 years. We found that the probability of work
loss is lessened among persons in jobs that have few
physical requirements, among those with high levels of
discretion over the pace and activities of work, and
among those who were able to stay on the job held when
the diagnosis was made. The probability of work loss is
increased among service workers. The findings of this
longitudinal study, showing that work characteristics
From the Multipurpose Arthritis Center, University of
California, San Francisco.
Supported by grant AM-20684 to the University of California, San Francisco, Multipurpose Arthritis Center, by the Robert
Wood Johnson Foundation, and by a Research Career Development
Award from the National Institute on Aging (grant K04-AG00273) to
Dr. Yelin. The opinions and conclusions expressed herein do not
necessarily represent the views of the funding agencies.
Edward Yelin, PhD; Curtis Henke, PhD; Wallace
Epstein, MD.
Address reprint requests t o Edward Yelin, PhD, 350
Pamassus Avenue, Suite 407, San Francisco, CA 94117.
Submitted for publication July 16, 1986; accepted in revised
form December 12, 1986.
Arthritis and Rheumatism, Vol. 30, No. 5 (May 1987)
profoundly alter the probability of work loss among
persons with RA, are consistent with the findings of our
earlier cross-sectional studies of work outcome and RA.
Work disability-the
cessation of employment-is a common outcome for persons with rheumatoid arthritis (RA). In 2 previous studies, 1 using a
sample derived from the practices of rheumatologists
and 1 from a national, community-based sample, we
found that approximately one-half of all patients with
RA who are working at disease onset can expect to
stop working sooner than they would if they were
healthy (1,2).
Literature on work disability indicates that people who have chronic diseases stop working when
functional impairment from the illness interacts with
the physical requirements of jobs and with the social
characteristics of work (2-6). In comparison with most
other chronic conditions, RA is a common cause of
work loss because its functional limitations are numerous and severe (7). However, many RA patients who
have worked in the past do not experience work loss.
For those individuals who eventually stop working,
work loss is only the final outcome of a long and
sometimes complicated process of accommodating
work to the disease, a process involving changes in
working conditions within jobs, and changes in jobs.
The purpose of this paper is to describe the patterns of
adjustments in work that are made by people with
RA-specifically , to describe the employment history
of persons with RA, the incidence and prevalence of
work loss over time, and the risk factors for work loss.
Data sources. This report is a compilation of data
from a panel of individuals with RA. The panel was formed
in 1982 and 1983. We have now observed the panel members
for an average of 3% years. To form the panel, we randomly
sampled one-half (n = 57) of the board-eligible rheumatologists in northern California. Of these 57 rheumatologists, 7
reported that they were not in practice and 10 declined to
participate. The 40 who did participate listed all patients
meeting strict criteria for RA who presented during a prospectively specified 1-month period, and they provided us
with information on the stage of illness, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF) presence or
absence, count of anatomic sites with erosions, and current
drug therapy for each patient. The rheumatologists listed 847
patients, of whom we interviewed 822 (97.1%). The initial
patient interview collected data on symptoms, functional
ability (including the Stanford Health Assessment Questionnaire [HAQ]), work status, use of health care providers, and
health insurance.
In 1984, we reinterviewed 754 of the original cohort
(92%); in 1985, we reinterviewed 698 (93% of 754; 85% of
822). Of the 124 patients from the original cohort not
interviewed in 1985, 30 were deceased, 4 were institutionalized, 2 reported that their physicians no longer believed they
had IIA, 56 were contacted but refused to complete one or
both of the followup interviews, and 32 (4% of the original
cohort) were lost to followup. Details of the composition of
the panel at baseline and at followup are given in references
8-10. Characteristics of those patients who were reinterviewed did not differ from those who were interviewed only
in the baseline year.
At the baseline interview, 390 patients from the panel
reported that they had worked for pay at some point in their
lives and that they were going to be under age 65, the normal
age of retirement, in 1985. This paper concerns these 390
individuals, of whom 353 (91%) were reinterviewed in 1985.
(Four percent of the 390 patients were lost to followup.)
Data collection. We designed a survey to be administered to the 353 persons who remained in the panel in 1985
and who reported having a work history. The survey followed the format traditionally used in obtaining work histories ( I l ) , and which we had used in our earlier study of
disability and RA (1). The survey asked respondents to
recount their working conditions in the year their arthritis
was first diagnosed, in 1984, and in 1985. Specifically,
respondents were asked about occupation, industry, selfemployment status, union membership, size of firm, tenure
of employment, the physical requirements of the job (e.g.,
lifting, reaching, gripping, walking), supervisory status, and
the individual’s autonomy with respect to the pace, time,
and activities of the job. Respondents also reported changes
within jobs, including all accommodations made by employers because of the respondents’ illnesses. Finally, they
reported if and when they changed jobs or left work entirely.
Table 1 details the medical, social, and work characteristics of the 353 individuals interviewed for this study.
Data analysis. Since we used descriptive information
on the work history of persons with RA, statistical analysis
was not necessary. As part of this descriptive information,
Table 1. Characteristics of study population
Percentage of
patients with
Education (years)
Widowed, separated, divorced
Painful joints (no.)
Change in painful joints (no.)*
Swollen joints (no.)
Change in swollen joints (no.)*
Stiff joints (no.)
Change in stiff joints (no.)*
Years since diagnosis
Comorbid conditions (no.)
White collar occupations
Blue collar occupations
Duration of employment (years)
* Between baseline year and
Mean t
10 2 4
1 2 4
6 k 3
0 1 3
9 2 5
0 2 4
11 5 8
1 2 1
9 2 8
we used life-table methods (12) to calculate rates of the
incidence and prevalence of work loss for each of the first 15
years after diagnosis. In the calculation of these rates, this
method took into account the duration of time between
diagnosis and disability for each subject.
Finally, we assessed the risk factors for work loss by
regressing work status in 1985 on demographic characteristics (age, sex, race, marital status, and education), symptoms (the number of painful, swollen, and stiffjoints; and the
change in the number of painful, swollen, and stiff joints
between the baseline and interview years), seventy (the
number of anatomic sites with erosions, the presence or
absence of an elevated ESR, the presence or absence of RF,
and current medications), overall health status (the number
of chronic conditions, respondents’ assessments of overall
health status, and the change in these 2 parameters since
baseline), functional capacity (the HAQ score and change in
HAQ score since baseline), and work characteristics in the
year the RA was first diagnosed (occupation, industry,
self-employment, union membership, size of the firm and
office, duration of employment, number of physical activities
required at the job, number of activities of the job over
which individual has discretion, and supervisory status).
Work status was dichotomous (working versus disabled). Accordingly, we used logistic regression for these
estimations. The chi-square statistic for each independent
variable in the regression indicates the strength of its association with work status (test size = 0.05). We used the
coefficients for each independent variable to estimate the
covariates-adjusted relative risk for disability associated
with that variable (for example, the relative risk of disability
among unionized and nonunionized workers after the effect
of other variables has been taken into account). We reported
relative risks only for those independent variables which
significantly affected work status. The relative risk for di-
chotomous variables was calculated for the values 0 and 1.
For continuous variables, we made this calculation for
values that were one-half a standard deviation above and
below the mean in the sample as a whole. We also determined the maximum potential effect that demographics,
health status, disease severity, symptoms, function, and
work variables have on the probability of work loss. We
calculated these effects by setting the values of each variable
within a major group (e.g., demographic characteristics) at
its minimum and maximum values, while all other variables
in the equation were given mean values across the study
population. This allowed us to estimate the extent to which
changes within a group of variables alter the probability of
disability when there is no other change.
The onset of RA is a profound cause of withdrawal from the labor force. Within roughly a decade,
approximately one-half of the patients with RA who
had been working during the year of diagnosis were no
longer employed (Table 2). Most patients who stopped
working did so because they claimed to be disabled by
the RA, although 2%, 3%, and 5%, respectively,
claimed unemployment for non-health reasons, had
become housewives, or were retired for non-health
Table 3 shows the work status in the year of
diagnosis and in 1985 for any individual with RA who
had ever worked for pay. The number of patients who
withdrew from work after diagnosis (127 patients,
Table 2) is somewhat offset by the 47 patients who
began employment after diagnosis of RA. These 47
were primarily students or housewives at disease
onset. Some of them subsequently left work because
of RA or other reasons. As a result of the movement in
and out of the labor force, about one-half the patients
with a history of labor force participation were working as of 1985.
Figure 1 displays graphically the work history
Table 2. Work status (in 1985) of 306 patients with rheumatoid
arthritis who worked in the year of diagnosis
No. (%) working in*
Work status
Working, on leave, or laid off
Retired for non-health reasons
Year of
306 (100)
* Percentages may not total 100%. due to rounding.
149 (49)
5 (2)
127 (42)
0 (0)
10 (3)
I5 (5)
Table 3. Work status (in the year of diagnosis and in 1985) of 353
patients with rheumatoid arthritis and a history of work
No. (%) working in*
Work status
Year of
Working, on leave, or laid off
Retired for non-health reasons
306 (87)
1 (0)
2 (1)
19 ( 5 )
23 (7)
2 (1)
181 (51)
6 (2)
136 (39)
1 (0)
13 (4)
16 ( 5 )
* Percentages may not total loo%, due to rounding.
of patients who began employment after diagnosis of
RA. Most of these 47 individuals entered the labor
force in the years between diagnosis and 1985. However, 15 of them left employment in 1985; two-thirds of
those who left work did so because of RA. A few
patients who had never worked began work in 1985, so
that ultimately, approximately two-thirds of the persons who were not employed when diagnosed, but
later began working, were working in 1985.
Figure 2 traces the work patterns of patients
who were employed at the time of diagnosis. Of the
306 patients who were working when diagnosed, about
one-third (106 patients) remained employed at the
same job in the period between diagnosis and 1985.
Most of them (94 patients) were still working in 1985.
However, many changed the nature of their job while
remaining employed at the same workplace. Of the 106
who stayed with the same employer, 62 changed their
occupations, the hours, or the procedures of the job.
Only 14% (44 of the 306) retained the same working
conditions from the year of diagnosis until 1985. Of
these 44, 5 stopped working in 1985 (data not shown).
About one-sixth of the patients employed when
diagnosed changed jobs during the time period between diagnosis and 1985. Few of them claimed that
this change was because of RA. Nevertheless, changing jobs did not forestall disability. Of the 57 who
changed jobs, 41 (72%) were still working in 1985. This
proportion was significantly smaller than the 89% (94
of 106) of those individuals who retained jobs they had
before the diagnosis of RA.
Far more people (143 patients) stopped work
altogether in the period between diagnosis and 1985
than stayed at the same job (106 patients) or changed
jobs (57 patients). Most of these attributed the loss of
work to RA. Approximately 10% of the 143 patients
who stopped work were employed again as of 1985.
Eighty-two percent of patients not working in 1985
No1 working
Between year of diagnosis and 1985
Not working
(8 5%)
(91 5%)
No1 working
131 9%)
* o n e person was on temporary k a Y e
probability of work loss. In other words, elevated
ESR, R F positivity, the count of erosions, and current
medications being taken did not predict who would
stop working after diagnosis, and in combination,
changes in severity altered the probability of work loss
by only 4%.
The RA patients' work status was shown to be
much more dependent on the symptoms of illness. As
symptoms increased from minimum to maximum values, the probability of disability increased by 36%.
The most influential symptom was the count of painful
joints. An increase of 1 SD in the number of painful
joints is associated with 1.76 times the probability of
work loss. It is the nature of the RA and its symptoms,
and not overall health status, that determined the work
status of persons with this illness. The level of
comorbidity, for example, did not significantly affect
disability status. Changes in overall health status altered the probability of work loss by only 8%.
Functional level, demographics, and characteristics of work were shown to have the largest impact
on the probability of work loss. As functional level
worsened, the probability of disability increased by
66%, when other factors were constant. Both the
absolute level of function and the change in ability to
function affected work status: the HAQ score had a
relative risk of >3, and the change in HAQ score had
a relative risk of >2. Although among the demographic
characteristics, only age reached statistical significance, several others almost did. Thus, as demo-
Due lo R A
Figure 1. Work history of patients with rheumatoid arthritis (RA)
who started working after the year of diagnosis.
(129 of 157) came from the ranks of those who had
stopped working previously.
Figure 3 shows the incidence and prevalence of
disability, by the number of years since diagnosis. Ten
percent of RA patients stopped work within a year of
diagnosis. For the next 13 years after diagnosis, the
incidence of disability varied from 2.5-lo%, and averaged 6.25%. The incidence for any one year seemed to
be subject to random variation within a limited range:
there were several rises and falls. The prevalence of
work disability rose precipitously at first, and then
seemed to increase more slowly over the years. By the
end of 5 years, almost one-third of persons with RA
had stopped working; after a decade, slightly less than
one-half were disabled. Although the rate of increase
in the prevalence of disability moderated over time,
the absolute prevalence rate continued to rise. These
data indicate that 6 of 10 persons with RA will become
disabled by the fifteenth year after diagnosis, and
approximately 90% will stop work by the thirtieth
Table 4 lists the factors which influence
whether an individual will stop working after onset of
RA. 'The table shows the specific variables within each
major group which significantly affected the probability of work loss among the patients studied, as well as
the covariates-adjusted relative risk associated with
each variable. It also gives the maximum amount that
each major group of variables can affect the probability of work loss, when the other variables in the
equation are assigned mean values. No individual
measure of the severity of RA was shown to affect the
Between year o! diagnosis and 1985
Year of diagnosis
I -
Stayed a1 Same p b
n=306 1100%)
Changed IOD
Due 10 RA
n i l 6 3 1533%)
n = i a (487%)
Figure 2. Work history of persons with rheumatoid arthritis (RA)
who were working in the year of diagnosis.
51 1
Prevalence of disability
Incidence of disability
1 0 j /--a
Years since diagnosis
Figure 3. Rates of incidence and prevalence of work disability among persons with rheumatoid
arthritis, by years since diagnosis.
graphic characteristics, in combination, changed, the
probability of disability would increase by 71%.
But it was the nature of the work itself which
had the greatest impact on the work status of persons
with RA. All else being equal, altering the characteristics of the job to make them more conducive to the
maintenance of employment increased by 97% the
probability of patients continuing to work, in effect
almost eliminating the prospect of work loss. Workers
in service industries were twice as likely to stop
working after diagnosis as were those in other industries. A I-SD increase in the physical requirements of
the job multiplied the risk of lost work by 1.5. Conversely, increasing the worker's discretion on the job
by 1 SD reduced the probability of work loss almost
fourfold (relative risk = 0.28).
We previously documented that RA is associated with high rates of work disability (1,2). In this
report, we again demonstrate this and add a dynamic
Table 4. The determinants of work disability among 270 patients
with rheumatoid arthritis (RA)*
Major group of
Severity of RA
Symptoms of RA
Specific variables
Maximum potential
within this group which
impact of this
affect work disability
major group of
rates (relative risk)t
variables (YO)
Number of painful
joints ( I .76)
Overall health status
HAQ score (3.28);
change in HAQ
score (2.03)
Age (1.73)
Service industry (2.06);
number of physical
activities ( I .46);
number of discretionary activities
* Analysis excludes individuals who claimed to be out of the labor
force for non-health reasons and individuals on whom data was
missing on a variable in the regression.
t Dependent variable takes a value of 0 if the person is working, I if
the person is disabled. Thus, a relative risk of > I connotes a higher
probability of work loss, and a relative risk of < 1 connotes a lower
probability. HAQ = Health Assessment Questionnaire.
element to the previous studies by tracing the work
history of the person with RA over time, and by
calculating a life-table to show how the probability of
disability increases in the years after diagnosis.
Within a decade after diagnosis, almost one-half
of the patients with RA stop work permanently. Fewer
than one-third of those working at the time of the
diagnosis will stay on the same job; fewer than onesixth will d o so without changes in occupation, hours,
or rules af work. Many will change jobs because they
were laid off from their former jobs, or will do so
voluntarily in the belief that they can find a job that
will be easier for a person with RA. But this strategy
will not necessarily forestall disability: only 72% of
those who changed jobs were still working in 1985.
Many more will simply stop work altogether, and most
RA patients never return to the labor force.
These work disability rates differ dramatically
from those experienced by the adult population without chronic disease or with other chronic conditions.
About three-quarters of an age- and sex-matched
population who are free of chronic disease and who
have a history of labor force participation work.
Two-thirds of those with a history of labor force
participation and 1 or more chronic conditions that
cause activity limitation work as well (13).
The data reported here concerning the determinants of work loss indicate that, severe illness notwithstanding, many persons with RA will continue to work
for years. We found that persons with few physical
tasks on the job and great discretion over the pace and
activities were much less likely to stop working. This
was the case despite disease which, on average, had
lasted for 11 years, and had resulted in 10 painful, 6
swollen, and 9 stiff joints (Table 1). These results
suggest that workers with physically demanding jobs
might be counseled t o seek to change to occupations
within their place of employment that are less demanding. Employers should be taught that the person with
RA needs flexible working conditions because of the
periodicity of illness, morning stiffness, and the need
to sometimes leave work in the middle of the day in
order to seek medical care.
The authors thank John Spencer, Sherry Markrow,
Jim Calvert, and Roy Kriedeman for their assistance.
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work, arthritis, dynamics, person, rheumatoid
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