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Keywords:

  • Rheumatoid arthritis;
  • Work disability;
  • Women's health

Abstract

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

Objective

To analyze factors associated with leaving employment among women with newly diagnosed rheumatoid arthritis (RA).

Methods

Women with RA were recruited from a national sample of rheumatologists in 1987 and 1998. Inclusion criteria were RA diagnosis <18 months earlier, age ≥18 years, and no other disabling health condition. The 1987 and 1998 cohorts comprised 48 and 91 women, respectively. Data were collected by telephone for 4 years. Survival analysis was conducted using Kaplan-Meier curves and a proportional hazards generalized linear model to assess whether the time to stopping work differed between the cohorts and to identify baseline predictors and time-varying covariates of leaving work.

Results

Most patients were age <50 years, married, had >12 years of education, and were white. Fifteen patients (31%) in the 1987 cohort and 24 patients (26%) in the 1998 cohort stopped working in the observation periods. Kaplan-Meier survival curves for each cohort were not significantly different. Multivariate analyses demonstrated that married women (P = 0.03) and those with joint deformities (P = 0.00) were more likely to stop working. A significant flares by cohort interaction (P = 0.01) indicated that, in comparison with patients in the 1998 cohort, those in the 1987 cohort with <2 disease flares had the lowest risk of stopping work and those with ≥2 flares had the greatest risk.

Conclusion

Unexpectedly, the cumulative rate of stopping work among women in the 1998 study did not differ from that among women diagnosed >16 years earlier. However, disease flares greatly affected employment in the 1987 but not the 1998 cohort, possibly indicating that newer medications were effective in maintaining functional status among those with more severe disease activity, measured by number of flares, in the 1998 group.


INTRODUCTION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

Studies of the psychosocial effects of rheumatoid arthritis (RA) indicate that disability in paid work is a pervasive social problem (1–8) for patients with RA. Many studies of RA indicate that demographic factors, work characteristics, and health status are related to maintaining employment (9–13). Recent reviews (1, 14) of factors contributing to risk of work disability indicate consistency among studies in finding that physically demanding work, lack of autonomy, worse pain and functional status, and fewer years of education are associated with increased risk of work disability.

A limitation of some studies of RA and patterns of work disability is that patients have had the diagnosis of RA for many years and recall bias may influence the reliability of the data. Furthermore, it is possible that the ability to maintain paid work and to maintain better physical and psychological health status is determined fairly early in the disease course. Results of studies investigating the experience of patients in the early days of the RA diagnosis (within the past 12–24 months) are mixed on whether the greatest risk of work disability and functional declines occurs early (15). Some investigators report that effects of RA occur before the diagnosis or soon after (4, 14, 16–25) and that these early experiences may determine long-term consequences over the course of the disease. Others suggest that disability occurs much later in the disease course (26–28). As with studies of patients with long-term disease, studies of RA during the early years have found that health status, family, and work factors contribute to increased risk of work disability (29).

Recent developments in the management of early RA with aggressive use of disease-modifying antirheumatic drugs (DMARDs) and the newer biologic agents may contribute to lower rates of functional decline and work disability (30). The effects of these treatments and cost effectiveness have not been studied extensively (31, 32). Two groups have shown that early use of DMARDs in the management of RA helps maintain work capacity (33, 34) and reduces the risk of work disability (35). The few studies of the effects of etanercept and infliximab (36, 37) demonstrate that use of these drugs is associated with higher employment rates and more hours worked per week.

The purpose of this study was to investigate rates of work disability among women with recent-onset RA and to assess demographics, work characteristics, and health status factors that affect the risk of becoming work disabled. The data were from 2 cohorts of patients with RA, one with women recruited in 1987–1988 and the other with women recruited in 1998–2000. Both cohorts were followed for 4 years. Having data from 2 cohorts 10 years apart offered a unique opportunity to determine whether factors influencing risk of work disability remained constant over time and whether trends in work disability have improved. Analysis of these 2 cohorts offers the opportunity to assess temporal changes in the illness experiences of women with recent-onset RA and to determine whether factors influencing risk of work disability changed in the time period. Much has been learned about the effects of RA in the early period just before and after diagnosis. Having such a historical record will contribute to a better understanding of how and whether these effects have changed over time.

We hypothesized that 1) the rate of work disability would be lower in the 1998 cohort than the 1987 cohort because of improvements in disease management and advances in pharmaceutical therapies; 2) women who had less severe self-reported symptoms would have lower rates of work disability; 3) women who had less demanding family work would have lower rates of work disability; and 4) women who were more satisfied with employment, had less physically demanding work, had better employment benefits such as paid sick leave, and wanted to work would have lower rates of work disability compared with other women.

PATIENTS AND METHODS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

Sample.

Both samples were recruited using a 2-stage selection process. First, for both studies, a random sample of rheumatologists using a table of random numbers was selected from the membership of the American College of Rheumatology (ACR; formerly the American Rheumatism Association). In the 1987 study, 116 physicians were randomly selected. Of those asked to participate, 56 agreed to refer any patients (male or female) with classic or definite RA according to the ACR criteria (38) regardless of time since diagnosis. In the 1998 study, 644 physicians were randomly selected and asked to participate, and 189 agreed. The lower response rate (29%) in 1998 likely reflects the greater clinical demands on rheumatologists and the increased number of requests to participate in clinical trials. Physicians in the 1998 study were asked to refer women with a diagnosis of RA using current ACR (formerly the American Rheumatism Association) criteria (39) and only those who had been diagnosed within the past 12 months. Because of lagging recruitment, we expanded the inclusion criteria to include women diagnosed within 18 months.

Second, office staff in both studies asked patients to complete a response card that was sent to the University of Connecticut. Research staff telephoned prospective participants, explained the study, and conducted a telephone interview at a convenient time. Participants were interviewed annually by telephone for the next 3 years. Physicians also completed a clinical assessment form in the baseline year.

For this analysis, the sample for the 1987 cohort was assembled by selecting from the final sample employed women diagnosed within the past year. In the 1987 study, 1,049 individuals returned response cards, 988 completed the baseline interview, and 498 were employed. Of these 498 employed participants, 107 were diagnosed in the past year and 48 were women. In the 1998 study, 187 female patients returned response cards to the university staff. Of these, 30 were not eligible, 23 refused, and 157 agreed to participate. Of the 157 who agreed to participate, 91 women were employed.

Possible sample bias.

There could be some small differences in the samples because of the changed diagnostic criteria and the differences in time since diagnosis. Regarding the diagnostic criteria, our exclusion criteria for the 1987 sample aligned well with the 1987 criteria; therefore, we do not believe that there were any differences in the diagnosis of RA for women included in the 2 samples. We only included patients with definite and classic RA in the 1987 study; we excluded those with a probable or possible diagnosis; finally, we excluded anyone who had other rheumatic conditions from both samples. As Arnett and colleagues point out, “the new criteria preserve continuity by retaining many features of the old criteria set and, in fact, closely parallel the old definition of definite or classic RA” (39).

There also could be some small differences in the sample because we expanded recruitment in the 1998 study to include patients diagnosed at 18 months. We believe that 12 or 18 months is an arbitrary cutoff, and many studies of recent-onset RA include patients who were diagnosed up to 2 years prior. The critical factor is that we captured information on women in the early course of their disease in both studies. It was not possible to identify with great precision the exact date of onset of the disease or symptoms, therefore we relied on the date of diagnosis, which could be documented. Including some women with more time since diagnosis in the 1998 study should not appreciably affect the results, particularly because the majority, 84 of the 91 patients, in the 1998 study were diagnosed 12 months earlier or less.

Variables.

Data on demographic, health status, work, and family characteristics were collected.

Demographics

Demographic characteristics included age, years of formal education, marital status, and race. Income was assessed using the US census categories and was dichotomized at the median income of $40,000 adjusted to 1998 dollars for the 1987 participants.

Work characteristics

Participants reported total number of hours worked; how much they liked work; whether they preferred to work full time, part time, or not at all; whether their job was mostly mental, mostly physical, or part mental and physical; occupation; whether they supervised people; and how much paid sick time they had. These variables were dichotomized for the analyses as follows: total number of hours was grouped into <40 hours and ≥40 hours per week; participants who liked work a great deal were compared with those who liked work somewhat or not at all; wanting to work full time was compared with wanting to work part-time and not at all; mostly mental work was compared with part mental work and mostly physical work; and white collar workers were compared with those in blue collar occupations.

Family/social characteristics

Participants were asked to rate satisfaction with their ability to perform household duties from very satisfied to very dissatisfied, and were asked if they could take a day off easily. They also reported the number of individuals living in the household. Satisfaction with ability was dichotomized into very satisfied and satisfied in one group and neutral, dissatisfied, and very dissatisfied into a second group. Being able to take a day off very easily was compared with not easily or not able to do. Number of individuals in the household was divided into 1–2 individuals and >2.

Social support was evaluated using the Qualitative Social Support Scale designed to measure how supportive the social network is perceived to be. The scale contains 20 Likert-type items scored on a scale of 1 (never true) to 4 (always true) that ask about perceptions of social support received by important others, such as feedback, task assistance, and ego support. Four items assessed relationship strain (e.g., the extent to which a relationship is stressful) and were reverse scored (40) (Cronbach's α = 0.82).

Self-reported health status

Pain was assessed using a visual analog scale. Participants were asked to rate pain on the day of the interview from 0 (no pain) to 100 (the most pain possible). One or more days of missed work was compared with not missing any days, and sick time was grouped as a week or longer or some/none.

Physician-assessed health status

Physicians were asked to complete a clinical assessment form at baseline. They reported the number of flares in the past year, presence of joint deformities in 6 areas (wrists/hands, ankles/feet, shoulder, elbows, knees, other), radiographic stage (I, II, III, or IV) (41), and presence of rheumatoid factor. For the analyses, the variables were dichotomized at the median category, which was ≥2 for flares, ≥1 for joint deformities, and II or higher for radiographic stage (none of the participants was in stage IV).

Statistical analysis.

Survival analysis methods were applied to identify variables that affected risk of terminating employment in the time following entry to the study. Survival curves, using the Kaplan-Meier method, were used to inspect employment patterns relative to time and to identify any systematic differences in continuation or cessation of employment between the 2 cohorts. Because data on the continuation/cessation of employment were collected only during annual interviews, the times of changes in employment status were interval censored. Following methods described by Hosmer and Lemeshow (42), we applied a modified form of proportional hazards regression that allowed us to model relationships between patient characteristics and employment and to account for interval censoring. Models were fitted using bivariate and multivariate approaches to understand both the effects of individual variables on employment and the simultaneous effects of multiple variables. Because the study samples were assembled using a 2-stage nested sampling approach, standard errors, statistical tests, and confidence interval estimates based on these models were adjusted for the effects of cluster sampling.

In the multivariate analyses, model building was performed by entering variables sequentially in 5 blocks. The blocks and their order were as follows: demographic variables, self-assessed health status, physician-assessed health status, family/social characteristics, and employment characteristics. Within each block, a forward stepwise selection strategy was applied based on a 5% level of significance. Variables found to be significant within a block were retained when the next block of variables was evaluated. The cohort effect, i.e., whether the participant was in the 1987 or 1998 cohort, was included as a covariate throughout the model building process. Once all blocks had been evaluated, first-order interaction terms were evaluated. Due to the limited sample size, potential interaction terms were added to the model only one at a time. In the final models with interaction terms, we decided to include variables based on a 10% level of significance because the small sample size might obscure significant effects that were worthy of investigation in future studies.

RESULTS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

Description of the samples.

Data on the descriptive characteristics of the women in the studies are presented in Table 1. Most women were <50 years of age, had more than a high school education, were married, and were white. The only significant difference in the demographic characteristics between the 2 cohorts was that the women in the 1998 cohort were in more affluent households, adjusting to 1998 dollars.

Table 1. Comparison of baseline characteristics between 1987 and 1998 cohorts of women with recently diagnosed rheumatoid arthritis who were employed at study entry*
Characteristics1987 cohort (n = 48)1998 cohort (n = 91)
  • *

    Values are the number (percentage).

  • Proportions are significantly different using a chi-square test statistic with P < 0.05.

Demographic  
 Age ≥50 years21 (43.8)27 (33.0)
 Beyond high school education23 (47.9)55 (60.4)
 Married29 (60.4)56 (61.5)
 Non-Hispanic white42 (87.5)73 (80.2)
 Income >$40,000 (adjusted to 1998 income levels)20 (41.7)54 (59.3)
Work status  
 Work ≥40 hours per week25 (52.1)59 (64.8)
 Like work a great deal31 (64.6)40 (44.0)
 Want full-time work22 (45.8)29 (31.9)
 Mostly mental job9 (18.8)28 (30.8)
 White collar38 (79.2)70 (76.9)
 Supervisor28 (45.8)37 (40.7)
 A week or more of sick time per year26 (54.2)50 (54.9)
Family/social characteristics  
 Very satisfied and satisfied with household activities25 (52.1)45 (49.5)
 1–2 individuals in household22 (45.8)49 (53.8)
 High social support (score ≥63)25 (50.0)46 (50.5)
 Very easily take day off26 (54.2)49 (53.8)
Self-assessed health status  
 High pain (score ≥25)27 (56.3)55 (60.4)
 Missed ≥1 days of work in past week8 (16.7)19 (20.9)
Physician-assessed health status  
 High total flares (≥2)33 (68.8)55 (60.4)
 High total joint deformities (≥1)19 (39.6)20 (22.0)
 Disease stage II or III25 (52.1)21 (23.1)
 Rheumatoid factor positive41 (33.3)70 (76.9)

Women in the 2 cohorts had similar working conditions. Most participants worked ≥40 hours per week, although most did not want to work full time and would have preferred part-time work or staying at home. The only significant difference was that women in the 1987 cohort liked their jobs more than women in the 1998 cohort.

There were no significant differences in family structure or family work responsibilities and most women reported the ability to take a day off easily, satisfaction with ability to do family work, and households with 1–2 additional persons. Most women had supportive social networks, with a median score of 63 out of a possible total of 80.

Physicians reported that disease activity was fairly high among women in both cohorts, with >60% reporting ≥2 flares in the previous year. Physicians also reported a high percentage of women already having deformities in at least 1 joint group within the first year of diagnosis. Women in the earlier cohort had significantly more deformities than the later group (39.6% in the 1987 group compared with 22% in the 1998 group). Furthermore, women in the earlier cohort were significantly more likely to be in radiographic stage II or III, indicating that, overall, women in the earlier cohort were in worse clinical health status as assessed by their physicians. Interestingly, more women in 1998 were positive for rheumatoid factor, which could be a function of more sensitive laboratory testing in the later years.

Cohorts were similar on self-reported pain levels and days missed from work. Most participants (56.3% in the 1987 cohort and 60.4% in the 1998 cohort) reported a score of ≥25 on the 100-point visual analog scale, and 16–20% missed ≥1 day from work in the previous week.

Kaplan-Meier survival curves of employment patterns relative to time for the 1987 cohort compared with that for the 1998 cohort are presented in Figure 1. In total, 15 (31%) of 48 patients in the 1987 cohort and 24 (26%) of the 91 patients in the 1998 cohort stopped working in the followup period. As shown in Table 2, a higher cumulative proportion of patients in the 1987 cohort ended employment during the followup period; the differences in overall survival patterns were not significant. The hazard ratio (HR) for the cohorts was 0.83 (95% confidence interval [95% CI] 0.44–1.58, P = 0.57). The cumulative proportions in both cohorts approximated the well- established rate of about half of patients employed at disease onset who leave the workforce within 10 years (28). It should be noted, however, that once participants left employment, they were censored or dropped from the analyses. Some participants may have returned to work at a later date.

thumbnail image

Figure 1. Proportion continuing employment among the 1987 and 1998 cohorts. Thin line = 1987 cohort; thick line = 1998 cohort.

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Table 2. Results of fitting bivariate models to investigate relationships between baseline characteristics and risk of discontinuing work data adjusting for study cohort*
 Cumulative percentage who discontinued workHR95% CIP
  • *

    HR = hazard ratio; 95% CI = 95% confidence interval.

  • Comparison group.

  • Time-dependent covariate.

Study cohort    
 198731.3 
 199826.40.830.44–1.580.57
Demographic characteristics    
 Age, years    
  <5026.1 
  ≥5031.41.220.64–2.310.54
 Education, years    
  ≥1223.11.560.83–2.940.17
  <1234.4 
 Marital status    
  Not married18.5 
  Married34.12.020.98–4.160.06
 Race    
  Nonwhite41.7 
  White25.20.470.22–0.990.05
 Adjusted income    
  <$40,00023.1 
  ≥$40,00032.41.720.87–3.400.12
Employment characteristics    
 Work hours    
  <4032.1 
  ≥4025.30.680.36–1.280.29
 Like work    
  Moderately/not at all32.4 
  Great deal23.90.520.27–0.990.05
 Desire for paid work    
  Want part time or stay home29.5 
  Want full time25.50.890.45–1.750.74
 Physical demands of job    
  Mostly physical or both physical and mental30.4 
  Mostly mental21.60.670.31–1.480.32
 Occupation    
  Blue collar38.7 
  White collar25.00.530.27–1.040.07
 Supervise others    
  No28.8 
  Yes27.10.850.45–1.620.63
 Paid sick days    
  Less than a week35.5 
  A week or more19.00.540.29–1.000.05
Family/social characteristics    
 Satisfaction with household activity    
  Not satisfied31.9 
  Satisfied/very satisfied24.30.830.44–1.570.57
 Take day off    
  Not easy31.3 
  Very easy25.30.820.44–1.530.53
 No. of individuals in house    
  ≥335.3 
  1–221.10.650.34–1.220.18
 Social support score    
  <6423.2 
  ≥6432.91.400.74–2.640.30
Health status    
 Total no. of joint deformities    
  No deformities20.0 
  ≥148.72.741.45–5.190.01
     
 Total no. of flares    
  0 or 123.5 
  ≥230.71.490.75–2.940.25
 Disease stage    
  Stage I23.7 
  Stage II or III37.01.670.86–3.270.13
 Rheumatoid factor    
  Negative35.8 
  Positive23.30.610.31–1.220.17
 Self-reported pain score    
  <2533.3 
  ≥2524.40.930.49–1.760.82
 Missed work    
  No missed work24.1 
  ≥1 days44.41.900.92–3.920.08

Bivariate associations between baseline characteristics and stopping work.

Table 2 presents the HRs from a series of regression models in which cessation of employment was the dependent variable and each demographic, work, family, or health status measure was entered as a single covariate. The only significant demographic characteristic related to risk of leaving work was race, with white patients having approximately half the risk of leaving employment (HR 0.47, 95% CI 0.22–0.99) compared with nonwhite patients.

The only significant employment characteristic associated with risk of work disability was how much participants liked their work. Those who liked their work a great deal had approximately half the risk of becoming work disabled compared with those who reported liking work a moderate amount or not at all (HR 0.52, 95% CI 0.27–0.99, P = 0.048).

Among the physician-assessed variables, having ≥1 joint deformity greatly increased the risk the leaving employment. Patients with ≥1 deformity were almost 3 times as likely to stop working as those with no deformity (HR 2.74, 95% CI 1.45–5.19, P < 0.01). Self-reported pain and days missed from work were not significantly related to risk of work disability.

Multivariate analysis.

The results of the model building process are presented in Table 3. In the presence of other predictive factors, women without flares in the more recent study (1998 cohort) were significantly more likely to stop working compared with women without flares in the earlier cohort (HR 6.6, 95% CI 1.19–36.5, P = 0.03). Women who were married were more likely to stop working than those who were not married (HR 3.34, 95% CI 1.5–7.4, P = 0.01). Clinical health status reported by physicians was very important as patients with more joint deformities and those with more disease flares were considerably more likely to stop working compared with patients with no deformities (HR 3.37, 95% CI 1.74–6.5, P = 0.00) and those not having any disease flares (HR 8.8, 95% CI 2.0–38.7, P = 0.01).

Table 3. Variables included in the final multivariate model of continuation/cessation of employment*
 HR95% CIP
  • *

    HR = hazard ratio; 95% CI = 95% confidence interval.

1998 study member6.601.19–36.460.03
White0.520.24–1.110.09
Married3.341.51–7.390.01
White collar occupation0.490.20–1.160.11
≥1 joint deformity3.371.74–6.500.00
≥2 flares in past year8.802.0–38.730.01
Flares by cohort interaction0.090.02–0.490.01

The effect of flares differed between cohorts in that there was a significant flares by cohort interaction (P = 0.01). Patients in the earlier study with more flares were more likely to leave employment. The interaction effect is illustrated in Figure 2. The lines representing the 1998 cohort almost completely overlap, indicating that their risk was the same regardless of number of flares. For the 1987 cohort, patients with no flares were the least likely to leave employment whereas women with ≥1 disease flares had the greatest risk of stopping work.

thumbnail image

Figure 2. Proportion continuing employment among those with and without flares in the 1987 and 1998 cohorts. Thin solid line = 1987/flares; thin broken line = 1987/no flares; thick solid line = 1998/flares; thick broken line = 1998/no flares.

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Two other variables remained in the model, although they did not achieve statistical significance. White race (P < 0.09) and white collar occupation reduced the risk of work disability (P = 0.106) compared with nonwhite race (HR 0.52, 95% CI 0.24–1.11) and blue collar work (HR 0.49, 95% CI 0.2–1.16).

DISCUSSION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

There has been considerable discussion of whether effects of RA occur early in the disease process or whether disease progression occurs slowly with more limited effects in the early years. This analysis offers the unique opportunity to examine effects with respect to paid work and whether they have changed over time. The women who participated in this study had been diagnosed with RA for less than 18 months. The physicians of the participants reported considerable disease activity among their patients in the previous year with more than 60% having had ≥2 disease flares, 60% having had ≥1 joint deformities, and 33% having progressed to stage II or III in 1 year. Women in the more recent cohort had better overall clinical status compared with those in the earlier study despite a greater prevalence of positive rheumatoid factor among the more recent cohort. This improved clinical picture could be the result of more effective clinical treatment among women in the 1998 cohort compared with the 1987 cohort, including prescription of new medications. Interestingly, self-reported pain levels were about the same in the 2 groups, with a majority reporting pain scores >25 on a 100-point scale and 30% reporting pain levels >50.

The cumulative rate of work disability among women in the 2 samples was high: 31% and 26% for the 1987 and 1998 cohorts, respectively. These rates are similar to those reported in European studies of recent-onset RA that followed patients for 5 years rather than 4 years (29). This represents a major social impact of RA that occurs fairly early in the disease course for these women. The rate was slightly lower for women in the 1998 cohort, but these differences were not significant.

Our study found clinical factors to be very important in predicting work disability. Having more flares and deformed joints greatly increased the risk of leaving the workforce. The interaction effect, which indicated that flares were important only for women in the earlier cohort, was intriguing. This effect indicates that reasons for leaving work are changing in that patients entering the study in 1998 left the workforce for reasons other than increased disease activity. In 1998 these factors might have included the negative effects of prevailing economic conditions and/or the changing economic structure towards a more service-based economy. Further investigation is needed to assess the underlying mechanisms accounting for this effect.

Finally, marital status was a significant factor in that married women had a greater tendency to leave the workforce compared with those who were unmarried. This finding may be related to the financial assistance that a spouse provides. It also could be related to the greater physical and social demands placed on married women with families. Although family size and satisfaction with performing household activities were not significantly related to work disability, other factors such as family-work conflict and the instrumental and nurturant family demands could be important risk factors for work disability and deserve further attention.

The results of this study should be viewed cautiously. Different diagnostic criteria were used in the 2 samples, although the changes in the criteria should not cause any appreciable difference in the diagnosis of RA among women in the 2 studies. However, because disease flares were much more important in the earlier cohort, it is possible that changes in criteria could have an effect. There also could be some differences in the samples because the 1998 sample included women who had a diagnosis of RA for a longer period. Again, this should not have a major effect on the results because we captured information on women in the early experiences of the disease. Small sample size limited the power of the study to detect small effects and the possibility of investigating the effects of simultaneous interactions between covariates. Therefore, some effects that were clinically significant and that could have policy implications for the treatment of patients with RA may have been missed. Some important variables concerning the structure of paid and family work, such as control over work and work demands, which are potentially critical variables for women with a chronic health condition, were not analyzed because this information was not uniformly collected in both samples. However, the results are consistent with other studies of individuals with recent-onset RA and further build on what is known about disease progression in the early years.

AUTHOR CONTRIBUTIONS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES

Dr.Reisine had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study design. Reisine, Fifield.

Acquisition of data. Reisine.

Analysis and interpretation of data. Reisine, Fifield, Walsh, Dauser.

Manuscript preparation. Reisine, Dauser.

Statistical analysis. Fifield, Walsh, Dauser.

REFERENCES

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. PATIENTS AND METHODS
  5. RESULTS
  6. DISCUSSION
  7. AUTHOR CONTRIBUTIONS
  8. REFERENCES