Table 3.
Cox proportional hazards models assessing the risk of worsening disability.
| Forward Risk of Worsening Disability N=22,432; PY=58,437 |
VARA Registry Risk of Worsening Disability N=1,574; PY =3,953 |
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|---|---|---|---|---|
|
| ||||
| HR (95% CI) | p | HR (95% CI) | p | |
|
|
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| Baseline HAQ/MD-HAQ | 0.52 (0.51, 0.54) | <0.001 | 0.51 (0.46, 0.58) | <0.001 |
| Follow-up Duration (per yr) | 1.11 (1.09, 1.13) | <0.001 | 1.37 (1.21, 1.55) | <0.001 |
| Age (per 10 yrs) | 1.00 (0.98, 1.01) | 0.80 | 1.04 (0.97, 1.11) | 0.22 |
| Male | 0.66 (0.63, 0.69) | <0.001 | 0.96 (0.76, 1.22) | 0.85 |
| Caucasian | 0.87 (0.81, 0.93) | <0.001 | 0.84 (0.72, 0.98) | 0.03 |
| Enrollment BMI | ||||
| <20 kg/m2 | 0.83 (0.72, 0.95) | 0.006 | 1.05 (0.73, 1.50) | 0.80 |
| 20–25 kg/m2 | 0.93 (0.88, 0.97) | 0.001 | 1.07 (0.89, 1.27) | 0.47 |
| 25–30 kg/m2 | 1 (Reference) | -- | 1 (Reference) | -- |
| 30–35 kg/m2 | 1.14 (1.08, 1.20) | <0.001 | 1.12 (0.94, 1.33) | 0.16 |
| >35 kg/m2 | 1.25 (1.18, 1.33) | <0.001 | 1.33 (1.07, 1.66) | 0.01 |
| RDCI (Comorbidity Score) | 1.10 (1.09, 1.11) | <0.001 | 1.06 (1.01, 1.12) | 0.01 |
| Disease Duration (per 10 yrs) | 1.00 (1.00, 1.00) | <0.001 | 1.00 (0.94, 1.06) | 0.82 |
| Current Smoking | 1.12 (1.05, 1.22) | 0.002 | 1.01 (0.86, 1.18) | 0.93 |
| Time-Varying | ||||
| CRP, mg/dl | -- | -- | 1.04 (1.02, 1.07) | 0.001 |
| Swollen Joint Count (0–28) | -- | -- | 1.05 (1.04, 1.06) | <0.001 |
*
The comorbidity score was the Rheumatic Disease Comorbidity Index
Abbreviations: VARA= VA Rheumatoid Arthritis; PY= Person-Years; HR= Hazard Ratio; HAQ= Health Assessment Questionnaire; MD-HAQ= Multidimensional Health Assessment Questionnaire; BMI= Body Mass Index; RDCI = Rheumatic Disease Comorbidity Index; CRP= C-Reactive Protein