Table 3.
Multivariable linear regression model evaluating the association between low cumulative RA disease activity category as measured by DAS28ESR and femoral neck bone mineral density (gm/cm2) controlling for important demographic and clinical variables. The model was weighted by number of study visits.
| β | 95% CI | p-value | |
|---|---|---|---|
| Low disease activitya,b | 0.071 | 0.021 to 0.122 | 0.020 |
| Age at time of DXA (years) | −0.005 | −0.007 to −0.003 | <0.0001 |
| Female | −0.021 | −0.084 to 0.042 | 0.502 |
| Race/Ethnicity | |||
| Hispanic/Latino | −0.100 | −0.162 to −0.039 | 0.002 |
| Asian | −0.088 | −0.155 to −0.021 | 0.010 |
| Other | ref | -- | -- |
| RA duration (years) | −0.001 | −0.004 to 0.002 | 0.533 |
| BMI | 0.005 | 0.001 to 0.010 | 0.016 |
| bMDARD usec | 0.076 | 0.017 to 0.135 | 0.012 |
| Prednisone (mg/day)b | 0.004 | −0.005 to 0.012 | 0.381 |
| ACPA positive | −0.013 | −0.076 to 0.050 | 0.680 |
| OP medication use (ever) | −0.002 | −0.056 to 0.051 | 0.931 |
-DAS28ESR: Disease activity score 28-joints with erythrocyte sedimentation rate; DXA: dual x-ray absorptiometry; RA: rheumatoid arthritis; BMI: body mass index; bDMARD: biologic disease modifying anti-rheumatic drug; ACPA: anti-cyclic citrullinated peptide; OP: osteoporosis.
Low DAS28ESR ≤3.2 vs. moderate/high DAS28ESR >3.2.
Cumulative values calculated using trapezoidal area under the curve/observation time.
Calculated as proportion (%) of visits where participant was taking bDMARDs.