Table 3.
Multivariable Analysis of Predictors for Treatment Persistence
| Variable | Odds ratio (95% confidence interval) | P value |
|---|---|---|
| Cohort (ref: TNF inhibitor cyclers) | ||
| TNF inhibitor-alternative MOA switchers | 1.280 (1.165–1.406) | <.001 |
| Alternative MOA cyclers | 1.435 (1.220–1.689) | <.001 |
| Alternative MOA-TNF inhibitor switchers | 1.108 (0.941–1.304) | .219 |
| Age-group, yrs (ref: 55–64 yrs) | ||
| 18–34 | 0.880 (0.749–1.033) | .118 |
| 35–44 | 0.832 (0.741–0.934) | .002 |
| 45–54 | 0.897 (0.819–0.984) | .021 |
| Male (ref: female) | 1.090 (0.982–1.209) | .105 |
| Plan type (ref: EPO/PPO) | ||
| Comprehensive/indemnity | 1.003 (0.809–1.242) | .982 |
| HMO | 0.886 (0.782–1.004) | .058 |
| POS | 1.027 (0.889–1.187) | .717 |
| POS with capitation | 0.957 (0.524–1.747) | .886 |
| Other | 1.075 (0.931–1.242) | .323 |
| Missing/unknown | 0.969 (0.788–1.192) | .766 |
| Index year (ref: 2011) | ||
| 2010 | 1.007 (0.894–1.134) | .912 |
| 2012 | 0.936 (0.829–1.056) | .283 |
| 2013 | 0.758 (0.672–0.855) | <.001 |
| 2014 | 0.747 (0.655–0.852) | <.001 |
| Region (ref: South) | ||
| Northeast | 1.095 (0.972–1.233) | .137 |
| North Central | 1.201 (1.080–1.336) | .001 |
| West | 1.162 (1.041–1.297) | .008 |
| Unknown | 1.030 (0.669–1.584) | .894 |
| Rural (ref: urban) | 0.998 (0.896–1.112) | .973 |
| Charlson Comorbidity Index | 0.942 (0.898–0.988) | .014 |
| Any hydroxychloroquine in baseline | 1.002 (0.912–1.101) | .965 |
| Any leflunomide in baseline | 0.900 (0.808–1.002) | .054 |
| Any methotrexate in baseline | 1.145 (1.055–1.241) | .001 |
| Any sulfasalazine in baseline | 1.176 (1.015–1.362) | .031 |
| >1 targeted DMARDs preindexa | 0.863 (0.674–1.105) | .244 |
| Baseline total healthcare cost | 0.999 (0.997–1.001) | .146 |
| Baseline RA-related cost | 1.002 (0.998–1.006) | .348 |
| Baseline number of RA-related office visits | 0.997 (0.985–1.009) | .648 |
| Baseline PDC for all therapies | 1.951 (1.581–2.409) | <.001 |
a
Using a variable preindex period; other baseline measures used 12-month baseline preindex.
DMARDs indicates disease-modifying antirheumatic drugs; EPO, exclusive provider organization; HMO, health maintenance organization; MOA, mechanism of action; PDC, proportion of days covered; POS, point of service; PPO, preferred provider organization; RA, rheumatoid arthritis; ref, reference; TNF, tumor necrosis factor.