Table III.
Association between covariates of interest and earlier drug discontinuation.
| Methotrexate | TNFi | Prednisone | HCQ | SSZ | |
|---|---|---|---|---|---|
| n=15,082 | n=8,412 | n=11,627 | n=7,490 | n=4,359 | |
| Discontinued: 14,770 | Discontinued: 8,313 | Discontinued: 11,349 | Discontinued: 7,287 | Discontinued: 4,299 | |
| HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | |
| Age | |||||
| <60 yrs | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 60–70 yrs | 0.82 (0.79, 0.86)*** | 0.89 (0.84, 0.94)** | 0.98 (0.93, 1.03) | 0.92 (0.86, 0.97)* | 0.90 (0.83, 0.97)** |
| 70–80 yrs | 0.88 (0.83, 0.93)* | 0.92 (0.85, 0.99) | 0.98 (0.93, 1.04) | 0.94 (0.87, 1.02) | 0.96 (0.86, 1.06) |
| >80 yrs | 0.94 (0.87, 1.02) | 1.14 (0.99, 1.32)** | 0.88 (0.81, 0.96)* | 1.12 (1.05, 1.34)*** | 0.97 (0.82, 1.14) |
| Male | 0.90 (0.85, 0.95)*** | 0.80 (0.75, 0.86)*** | 0.86 (0.81, 0.91)*** | 0.93 (0.86, 1.00) | 0.86 (0.78, 0.96)** |
| Black | 1.13 (1.07, 1.19)*** | 1.08 (1.00, 1.16) | 1.05 (0.99, 1.11) | 1.31 (1.22, 1.41)*** | 1.17 (1.07, 1.28)* |
| Depression | 1.09 (1.04, 1.14)*** | 1.14 (1.09, 1.21)*** | 1.08 (1.03, 1.13)** | 1.14 (1.08, 1.21)*** | 1.13 (1.05, 1.22)** |
| Anxiety | 1.11 (1.06, 1.17)*** | 1.06 (1.00, 1.13) | 1.16 (1.09, 1.22)*** | 1.01 (0.95, 1.09) | 0.98 (0.90, 1.07) |
| CHF | 1.09 (1.02, 1.17)* | 1.06 (0.96, 1.17) | 1.06 (0.99, 1.14) | 0.96 (0.87, 1.06) | 1.01 (0.90, 1.13) |
| Malignancy | 1.05 (1.00, 1.11) | 1.11 (1.03, 1.20)* | 1.00 (0.94, 1.06) | 1.03 (0.95, 1.10) | 1.01 (0.92, 1.11) |
| Comorbidity Score (RDCI) | 1.03 (1.01, 1.04)** | 1.03 (1.01, 1.06)** | 0.99 (0.97, 1.01) | 0.97 (0.95, 0.99)* | 0.98 (0.95, 1.01) |
| 2010–2014 vs. 2005–2009 | 1.10 (1.05, 1.15)*** | 1.05 (0.99, 1.12) | 1.29 (1.23, 1.36)*** | 1.09 (1.03, 1.16)*** | 0.98 (0.90, 1.06) |
| Current smoker | 1.07 (1.00, 1.13)* | 1.11 (1.04, 1.20)*** | 1.14 (1.07, 1.22)*** | 1.07 (0.99, 1.15) | 1.02 (0.92, 1.12) |
| ACPA-positive | 0.87 (0.83, 0.91)*** | 0.94 (0.87, 1.01) | 0.90 (0.86, 0.95)** | 0.95 (0.89, 1.02) | 0.97 (0.88, 1.06) |
| Concurrent Prednisone | 0.97 (0.93, 1.01) | 1.13 (1.07, 1.18)*** | N/A | 1.00 (0.95, 1.05) | 1.07 (1.00, 1.15)* |
| Concurrent MTX use | N/A | 0.89 (0.85, 0.93)*** | 0.97 (0.93, 1.00) | 0.98 (0.93, 1.03) | 0.94 (0.88, 1.01) |
| Concurrent TNFi use | 1.07 (1.00, 1.13)* | N/A | 1.14 (1.07, 1.21)*** | 1.09 (0.99, 1.20) | 1.07 (0.95, 1.20) |
| Concurrent SSZ use | 1.05 (0.96, 1.14) | 0.96 (0.88, 1.05) | 1.13 (1.03, 1.25)* | 1.11 (1.02, 1.22)* | N/A |
| Initial Biologic | N/A | 0.87 (0.82, 0.91)*** | N/A | N/A | N/A |
*
p<0.05
**
p<0.01
***
p<0.001.
Additional variables were included in the models and are not shown (BMI category) or non-significant (CRP, disease duration >5 years, concurrent HCQ, diabetes, hypertension).
CHF: congestive heart failure; RDCI: Rheumatic Disease Comorobidity Index; ACPA: anti-cyclic citrullinated peptide antibody; MTX: methotrexate; TNFi: tumour necrosis factor inhibitor; SSZ: sulfasalazine; CRP: C-reactive protein; HCQ: hydroxychloroquine.