Table 3.
Multivariable negative binomial regression models for the association of baseline SLICC-FI and SDI scores with the change in SDI score during follow-up among SLE patients in the SLICC inception cohort.
| Univariable model (n = 1549) |
Multivariable model a (n = 1539) |
|||
|---|---|---|---|---|
| Incidence Rate Ratio (95% CI) |
p value | Incidence Rate Ratio (95% CI) |
p value | |
| Model 1: SLICC-FI | ||||
| SLICC-FI (per 0.05) | 1.26 (1.20 – 1.33) | <0.001 | 1.20 (1.14 – 1.27) | <0.001 |
| Model 2: SDI | ||||
| SDI (per 1.0) | 1.31 (1.20 – 1.43) | <0.001 | 1.17 (1.07 – 1.28) | <0.001 |
| Model 3: SLICC-FI & SDI | ||||
| SLICC-FI (per 0.05) | 1.23 (1.17 – 1.30) | <0.001 | 1.19 (1.13 – 1.25) | <0.001 |
| SDI (per 1.0) | 1.19 (1.09 – 1.31) | <0.001 | 1.10 (1.01 – 1.21) | 0.038 |
| Overall model comparisons | LR test statistic | p value | LR test statistic | p value |
| Model 1 vs. Model 3 | 15.35 | <0.001 | 5.18 | 0.023 |
| Model 2 vs. Model 3 | 67.64 | <0.001 | 40.49 | <0.001 |
| Akaike information criteria (AIC) | ||||
| Model 1: SLICC-FI | 3735.12 | 3566.78 | ||
| Model 2: SDI | 3787.41 | 3602.09 | ||
| Model 3: SLICC-FI & SDI | 3721.78 | 3563.60 | ||
a
Models adjusted for the following baseline characteristics: age, sex, steroid use, antimalarial use, immunosuppressive use, ethnicity/location, post-secondary education, and SLEDAI-2K.
Notes: SLICC = Systemic Lupus International Collaborating Clinics; FI = Frailty Index; SDI = SLICC / ACR Damage Index; LR = Likelihood Ratio