Session Information
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose: Rheumatoid arthritis (RA)
is most prevalent in those who are 60 years of age or older. It has not been
clearly established whether pain perception is different according to age in RA
patients. We investigated whether there is any difference in pain level to
similar synovial inflammation with aging using Modified Disease Activity Score
(MDAS), which was shown to have superior correlation with Magnetic Resonance
Image (MRI) detected synovitis.
Methods: For RA subjects enrolled in the
University of Pittsburgh Rheumatoid Arthritis
Comparative Effectiveness Registry (RACER), a cross-sectional analysis was
performed for all first visits available. Levels of inflammation were
calculated by MDAS28 score (=0.49 x ln(C-reactive protein (CRP)) + 0.15 x
Swollen joint count 28 (SJC) + 0.22 x Physician global assessment (PhGA) +1). Spearman’s correlations among pain (visual analog
scale, VAS), disease characteristics, comorbidities and American College of
Rheumatology (ACR) Core Data Set measures were calculated. Univariate and multivariate analyses were performed to
investigate association between pain level and age. Age was categorized into 2
groups (younger RA <60, older RA ≥ 60) in regression models.
Mann-Whitney U test was used to detect differences between two age groups.
Results: For the 740 subjects
analyzed, subject age was 61.2 ±13.7 (median ±SD) years with disease duration
of 14.4 ±12.4 years. In multivariate analyses, pain level had significant
negative association with age even after adjustment for race, gender,
comorbidities, and inflammation. (Table.1) In subjects with moderate
inflammation (defined by MDAS28 score above 50 percentile, N=370), older RA
subjects (age ≥ 60, N=189) had lower pain level, Tender Joint Count
(TJC), Patent Global Assessment (PtGA), PhGA, , Routine Assessment of Patient Index Data 3
(RAPID3), Disease Activity Score (DAS) 28-CRP than younger subjects (age <
60, n=157) but SJC, physical health by 12-Item Short Form Health Survey (SF12)
were not different between them. SF12-Mental Health was better in older RA
subjects. (Table.2). There were no significant differences between two age groups
in subjects with lower levels of inflammation (MDAS ≤ 50 percentile,
N=370).
Conclusion: Decreased pain level in
older RA patients with a similar degree of joint inflammation as younger RA
patients leads to under-estimation of disease activity measured by either
patient reported outcome (RAPID3) or composite disease activity index
(DAS28-CRP). This suggests that current clinical disease activity measurements
may not fully reflect the severity of disease in older RA patients.
|
Table.1 Multiple regression analyses of the associations of pain level with age adjusted for influences of covariates. Model 1 was adjusted for race, gender, comorbidities, and disease duration. Model 2 was adjusted as model 1 plus MDAS28. Model 3 was adjusted as model 2 plus physical & mental health (β: unstandardized coefficient, SE: Standard Error, MDAS28: Modified Disease Activity Score, 12-Item Short Form Health Survey (SF12)- Physical Health(PCS), Mental Health (MCS)) |
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|
Model |
Variables |
β |
SE |
p value |
|
1 |
Age |
-0.722 |
.008 |
0.014 |
|
Race |
1.199 |
.349 |
0.003 |
|
|
Gender |
-0..122 |
.259 |
.684 |
|
|
Charlson Score |
0.174 |
.083 |
.016 |
|
|
Disease duration |
-0.122 |
.000 |
.848 |
|
|
2 |
Age |
-0.700 |
0.270 |
.010 |
|
Race |
.989 |
.334 |
.003 |
|
|
Gender |
-0.171 |
.238 |
.474 |
|
|
Charlson Score |
0.146 |
.075 |
.053 |
|
|
Disease duration |
0.000 |
.0.000 |
0.366 |
|
|
MDAS28 |
0.735 |
.065 |
.000 |
|
|
3 |
Age |
-.602 |
.163 |
.000 |
|
Race |
.619 |
.253 |
.015 |
|
|
Gender |
-.016 |
.187 |
.931 |
|
|
Charlson score |
.050 |
.060 |
.404 |
|
|
Disease duration |
0.000 |
.001 |
.961 |
|
|
MDAS28 |
.314 |
.055 |
.000 |
|
|
SF12-PCS |
-.147 |
.008 |
.000 |
|
|
SF12-MCS |
-.071 |
.007 |
.000
|
|
|
Table. 2 Comparisons between younger (age<60,n=157) and older (age>=60, n=189) RA patients with moderate inflammation (MDAS28 >50 percentile) (SJC: Swollen Joint Count, TJC: Tender Joint Count, PtGA: Patient Global Assessment, PhGA: Physician Global Assessment, SF12-PCS/MCS: 12-Item Short Form Health Survey (SF12)- Physical Health(PCS), Mental Health (MCS), DAS28-CRP: Disease Activity Score 28-C-Reactive Protein, RAPID3: Routine Assessment of Patient Index 3)
|
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|
|
Unadjusted (Mean ± SD) |
Adjusted (Mean ± SD) |
||||
|
|
Age < 60 |
Age ≥ 60 |
p value* |
Age < 60 |
Age ≥ 60 |
p value* |
|
Pain (VAS) |
6.36 (2.59) |
5.14 (2.75) |
<0.001 |
6.16 (1.87) |
5.06 (1.80) |
<0.001 |
|
SJC |
6.76 (5.92) |
6.88 (6.00) |
0.963 |
7.36 (3.85) |
7.06 (3.59) |
0.521 |
|
TJC |
6.74 (6.65) |
4.20 (5.46) |
<0.001 |
6.70 (2.89) |
4.84 (2.71) |
<0.001 |
|
PtGA |
5.56 (2.35) |
4.44 (2.50) |
<0.001 |
5.35 (1.78) |
4.52 (1.67) |
<0.001 |
|
PhGA |
4.89 (2.37) |
3.97 (2.27) |
<0.001 |
4.64 (1.67) |
4.03 (1.56) |
<0.001 |
|
RAPID3 |
4.51 (1.17) |
3.98 (1.09) |
<0.001 |
4.79 (1.62) |
4.04 (1.56) |
<0.001 |
|
DAS28-CRP |
4.94 (2.01) |
4.04 (2.02) |
<0.001 |
4.38 (1.02) |
3.97 (0.96) |
<0.001 |
|
SF12-PCS |
34.77 (9.88) |
35.27 (10.34) |
0.697 |
|
||
|
SF12-MCS |
44.27 (11.58) |
49.27 (10.93) |
<0.001 |
|
||
|
* p values < 0.0056 were considered statistically significant using the Bonferroni correction for multiple comparisons
|
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To cite this abstract in AMA style:
Hwang YG, Feng J, Eng H, Lyons J, Fabio A, Moreland LW. Decreased Pain Level with Aging Leads to Underestimation of Disease Activity in Rheumatoid Arthritis [abstract]. Arthritis Rheumatol. 2015; 67 (suppl 10). https://acrabstracts.org/abstract/decreased-pain-level-with-aging-leads-to-underestimation-of-disease-activity-in-rheumatoid-arthritis/. Accessed .« Back to 2015 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/decreased-pain-level-with-aging-leads-to-underestimation-of-disease-activity-in-rheumatoid-arthritis/