Session Information
Session Type: Abstract Submissions (ARHP)
Background/Purpose We previously found that household income less than $30k/yr and not owning a home influenced rheumatoid arthritis (RA) disease severity measures. We sought to further expand our findings to explore whether block group poverty (BGP) modified the associations between income and homeownership with RA health outcomes (RAHO).
Methods We carried out a cross-sectional analysis in 898 African American participants with RA in the CLEAR Registry. We assessed the main effects of BGP (≥20% vs. <20%) on RAHO, and explored whether BGP modified the associations between income or homeownership and RAHO. Multivariate regression models for continuous, binary and count outcomes were used to estimate beta coefficients (β), odds ratios (OR) and prevalence rate ratios (PRR), respectively, and their 95% confidence intervals (CI). Associations between income and homeownership on RAHO were stratified by BGP and interaction p-values calculated. All analyses were adjusted for gender, age, body mass index, disease duration, pack-years of smoking, number of comorbidities, current Methotrexate/Leflunomide use, current biologics use and study site.
Results The cohort had a mean age of nearly 55 years, was largely female, and had disease duration of nearly 8 years. In regression models comparing the effects of BGP ≥20% with BGP <20% on RAHO, we observed strong positive associations with DAS, JSN and joint erosions as well as with HAQ score (Table 1). Stratification of the effect of income on RAHO by BGP poverty revealed no statistically significant interaction. However, when stratifying the analyses of homeownership, we observed effect modification that narrowly missed statistical significance (Table 2). Notably, among those who lived in an area with BGP ≥20%, non-homeowners had a 69% higher Joint Alignment and Motion (JAM) score than homeowners (PRR=1.69; 95% CI=1.09-2.62), whereas there was no association with JAM score for homeownership among those living in an area with BGP <20% (interaction p-value=0.11). Other associations which narrowly missed statistically significant interactions were observed for joint space narrowing, joint erosion, and DAS (interaction p-values=0.13, 0.05, and 0.14, respectively).
Conclusion Our results suggest that block group poverty modifies the association between homeownership and joint damage measures. These findings suggest that further research is warranted to identify the underlying factors for these associations; for example monetary reasons precluding medication purchase or access to adequate medical care.
|
Table 1. Adjusted‡ estimates of cross-sectional associations of block group poverty≥20%£ with |
|
|
|
disease severity of rheumatoid arthritis in the total cohort of CLEAR African Americans |
|
|
|
Total Cohort (CLEAR I & II) (N=898) |
Block group |
|
|
poverty ≥20% |
||
|
Disease activity |
||
|
DAS (0-10)* (β) |
0.29 (0.08,0.50)¶ |
|
|
CRP levels (log mg/L) (0-386) (β) |
0.08 (-0.14,0.31) |
|
|
No. of Joint swelling (0-42)* |
1.07 (0.90,1.28) |
|
|
No. of Joint tenderness (0-42) |
1.14 (0.99,1.33) |
|
|
Joint damage |
||
|
Erosion (0-180) (PRR) |
1.39 (1.01,1.90)¥ |
|
|
JSN score (0-166) (PRR) |
1.28 (1.04,1.58)¥ |
|
|
JAM score (0-126)* (PRR) |
1.12 (0.89,1.42) |
|
|
Autoantibody status |
||
|
ACPA, % Positive (OR) |
1.20 (0.88,1.63) |
|
|
IgA-RF, % Positive (OR) |
1.05 (0.77,1.44) |
|
|
IgM-RF, % Positive (OR) |
0.97 (0.69,1.38) |
|
|
Self-report health status |
||
|
Fatigue VAS (0-10) (β) |
0.10 (-0.31,0.51) |
|
|
Pain VAS (0-10) (β) |
0.26 (-0.13,0.64) |
|
|
HAQ Score (0-3) (β) |
0.15 (0.05,0.24)¶ |
|
|
RAI Score (1-5) (β) |
0.09 (-0.04,0.22) |
|
|
HRQOL |
||
|
Limited activity days (0-30) (PRR) |
1.03 (0.89,1.19) |
|
|
Mentally Unhealthy days (0-30) (PRR) |
0.95 (0.82,1.09) |
|
|
Physically Unhealthy days (0-30) (PRR) |
0.96 (0.85,1.07) |
|
|
‡Adjusted for study site, gender, age, body mass index, disease duration, pack-years of smoking, number of |
||
|
comorbidities, current Methotrexate/Leflunomide use and current biologics
|
||
|
£Referent=Block group poverty <20%
|
||
|
*90 outlying values omitted from analysis
|
||
|
€Odds ratios (95% confidence intervals)
|
||
|
¥P-value <0.05, ¶P-value <0.01
|
||
|
|
||
|
DAS: disease activity score; CRP: C-reactive protein; JSN: Joint-Space Narrowing; JAM: Joint Alignment and Motion |
||
|
Score; ACPA: Anti-Citrullinated Peptide Antibodies; IgA-RF: Rheumatoid factor targeting Immunoglobulin A; IgM-RF: |
||
|
Rheumatoid factor targeting Immunoglobulin M; VAS: Visual Analog Scale; HAQ: Health Assessment Questionnaire |
||
|
(disability); RAI: Rheumatology Attitudes Index (helplessness); HRQOL: Health-Related Quality of Life.
|
||
|
Table 2. Adjusted‡ estimates for the association of household income <$30k£ and not owning your home† with disease severity |
||||||
|
measures in the CLEAR cohort, stratified by block group poverty |
||||||
|
RA outcome |
Household Income <$30k |
|
Non-Homeowner |
|
||
|
Poverty <20% |
Poverty ≥20% |
P€ |
Poverty <20% |
Poverty ≥20% |
P€ |
|
|
Disease activity |
|
|
|
|||
|
DAS (0-10)* (β) |
0.31 (-0.02,0.64) |
0.45 (0.04,0.85)¥ |
0.595 |
0.38 (0.07,0.70)¥ |
0.13 (-0.22,0.48) |
0.141 |
|
CRP levels (log mg/L) (0-386) (β) |
0.17 (-0.19,0.52) |
0.03 (-0.40,0.46) |
0.994 |
0.17 (-0.16,0.50) |
0.13 (-0.24,0.50) |
0.514 |
|
No. of Joint swelling (0-42)* |
1.39 (1.06,1.82)¶ |
1.42 (1.03,1.98)¥ |
0.595 |
1.24 (0.96,1.61) |
1.19 (0.87,1.61) |
0.598 |
|
No. of Joint tenderness (0-42) |
1.25 (0.99,1.57) |
1.34 (1.02,1.76)¥ |
0.679 |
1.33 (1.07,1.66)¥ |
1.25 (0.98,1.59) |
0.516 |
|
Joint damage |
|
|
|
|||
|
Erosion (0-180) (PRR) |
1.20 (0.74,1.94) |
1.16 (0.54,2.51) |
0.799 |
0.97 (0.62,1.52) |
1.29 (0.68,2.44) |
0.019 |
|
JSN score (0-166) (PRR) |
1.29 (0.97,1.71) |
1.30 (0.73,2.33) |
0.962 |
1.08 (0.83,1.41) |
1.37 (0.91,2.08) |
0.143 |
|
JAM score (0-126)* (PRR) |
1.26 (0.91,1.76) |
1.22 (0.73,2.04) |
0.852 |
1.23 (0.88,1.72) |
1.69 (1.09,2.62)¥ |
0.109 |
|
Autoantibody status |
|
|
|
|||
|
ACPA, % Positive (OR) |
1.43 (0.90,2.28) |
1.22 (0.68,2.21) |
0.907 |
1.47 (0.95,2.28) |
0.89 (0.54,1.49) |
0.237 |
|
IgA-RF, % Positive (OR) |
1.20 (0.74,1.95) |
1.18 (0.66,2.10) |
0.747 |
1.32 (0.83,2.08) |
1.02 (0.61,1.69) |
0.370 |
|
IgM-RF, % Positive (OR) |
1.80 (1.06,3.06)¥ |
1.55 (0.83,2.90) |
0.677 |
1.13 (0.68,1.87) |
1.13 (0.65,1.95) |
0.717 |
|
Self-report health status |
|
|
|
|||
|
Fatigue VAS (0-10) (β) |
0.33 (-0.29,0.95) |
0.89 (0.09,1.69)¥ |
0.139 |
0.73 (0.16,1.31)¥ |
0.53 (-0.14,1.21) |
0.802 |
|
Pain VAS (0-10) (β) |
1.25 (0.66,1.83)µ |
1.46 (0.73,2.19)µ |
0.355 |
1.24 (0.69,1.78)µ |
0.83 (0.21,1.45)¶ |
0.457 |
|
HAQ Score (0-3) (β) |
0.40 (0.26,0.54)µ |
0.30 (0.12,0.47)¶ |
0.538 |
0.26 (0.12,0.40)µ |
0.18 (0.02,0.33)¥ |
0.549 |
|
RAI Score (1-5) (β) |
0.46 (0.26,0.67)µ |
0.52 (0.28,0.75)µ |
0.677 |
0.37 (0.17,0.56)µ |
0.43 (0.23,0.63)µ |
0.878 |
|
HRQOL |
|
|
|
|||
|
Limited activity days (0-30) (PRR) |
1.27 (1.02,1.58)¥ |
1.23 (0.91,1.67) |
0.935 |
1.16 (0.95,1.42) |
1.20 (0.93,1.55) |
0.508 |
|
Mentally Unhealthy days (0-30) (PRR) |
1.20 (0.98,1.47) |
1.44 (1.06,1.95)¥ |
0.285 |
1.25 (1.03,1.52)¥ |
1.08 (0.83,1.39) |
0.329 |
|
Physically Unhealthy days (0-30) (PRR) |
1.08 (0.91,1.29) |
1.31 (1.04,1.65)¥ |
0.192 |
1.09 (0.92,1.28) |
1.17 (0.96,1.42) |
0.228 |
|
‡Adjusted for study site, gender, age, body mass index, disease duration, pack-years of smoking, number of comorbidities, current Methotrexate/Leflunomide |
||||||
|
use and current biologics
|
||||||
|
£Referent=Annual household income ≥$30k; †Referent=Owning your home
|
||||||
|
€Interaction P-value
|
||||||
|
*90 outlying values omitted from analysis
|
||||||
|
¥P-value <0.05, ¶P-value <0.01, µP-value <0.001
|
||||||
|
DAS: disease activity score; CRP: C-reactive protein; JSN: Joint-Space Narrowing; JAM: Joint Alignment and Motion Score; ACPA: Anti-Citrullinated Peptide |
||||||
|
Antibodies; IgA-RF: Rheumatoid factor targeting Immunoglobulin A; IgM-RF: Rheumatoid factor targeting Immunoglobulin M; VAS: Visual Analog Scale; HAQ: |
||||||
|
Health Assessment Questionnaire (disability); RAI: Rheumatology Attitudes Index (helplessness); HRQOL: Health-Related Quality of Life.
|
||||||
Disclosure:
R. J. Cleveland,
None;
J. Smith,
None;
A. A. Baldassari,
None;
B. L. Jonas,
None;
D. L. Conn,
None;
L. W. Moreland,
None;
S. L. Bridges Jr.,
None;
L. F. Callahan,
None.
« Back to 2014 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/modification-of-effects-of-household-income-and-homeownership-by-block-group-poverty-on-health-outcomes-in-a-cohort-of-african-americans-with-rheumatoid-arthritis/