Table 3.
Logistic Regression Model of TNF-Inhibitor Initiation in First Year by Insurance Type
| Public Insurance (n=268 ) | Private Insurance (n=818) | |||||
|---|---|---|---|---|---|---|
| Unadjusted OR (95% CI) | Adjusted ORa (95% CI) | Adjusted OR with Site of Careb (95% CI) | Unadjusted OR (95% CI) | Adjusted ORa (95% CI) | Adjusted OR with Site of Careb (95% CI) | |
| Male | 1.29 (0.76–2.20) | 1.44 (0.69–2.98) | 1.4 (0.65–3.03) | 0.93 (0.69–1.26) | 0.96 (0.67–1.38) | 0.97 (0.67–1.41) |
| Age (per 1 year increase) | 1.07 (1.02–1.13)* | 1.01 (0.94–1.08) | 1.0 (0.93–1.07) | 1.10 (1.07–1.13)** | 1.03 (1.00–1.07) | 1.03 (0.99–1.06) |
| Race/Ethnicity | ||||||
| White | 0.82 (0.49–1.38) | 1.29 (0.40–4.19) | 1.34 (0.38–4.78) | 0.76 (0.51–1.14) | 1.08 (0.50–2.31) | 1.15 (0.53–2.52) |
| Black | 1.42 (0.64–3.18) | 1.24 (0.35–4.34) | 1.47 (0.39–5.47) | 2.77 (1.34–5.71)* | 1.97 (0.74–5.28) | 2.11 (0.77–5.75) |
| Hispanic | 1.15 (0.65–2.06) | 1.15 (0.33–4.0) | 1.40 (0.38–5.17) | 0.96 (0.55–1.66) | 0.88 (0.41–1.90) | 0.90 (0.41–1.98) |
| Asian | 0.56 (0.17–1.87) | 0.45 (0.08–2.56) | 0.48 (0.07–3.22) | 0.90 (0.49–1.62) | 0.91 (0.41–2.01) | 0.93 (0.41–2.12) |
| Native American, American Indian or Alaskan Native | 1.39 (0.34–5.66) | 2.25 (0.35–14.43) | 2.66 (0.36–19.62) | 0.27 (0.03–2.64) | 0.19 (0.01–2.55) | 0.20 (0.01–2.83) |
| Middle Eastern/North African | 2.08 (0.40–10.76) | 1.32 (0.21–8.67) | 1.28 (0.19–8.79) | |||
| Native Hawaiian or Other Pacific Islander | 1.66 (0.15–18.32) | 0.43 (0.03–6.26) | 0.47 (0.03–6.69) | |||
| Other * | 1.53 (0.56–4.17) | 9.06 (0.54–153.09) | 5.88 (0.34–102.9) | 1.10 (0.24–4.95) | 1.01 (0.19–5.46) | 1.10 (0.20–6.02) |
| Prefer not to state | 1.38 (0.12–5.36) | 0.57 (0.02–13.95) | 0.74 (0.03–19.09) | 0.82 (0.29–2.37) | 0.83 (0.20–3.55) | 0.85 (0.20–3.68) |
| Self-Reported Household Income (ref >150K) | ||||||
| <25K | 0.39 (0.05–2.85) | 0.48 (0.03–6.83) | 0.50 (0.03–9.34) | 0.77 (0.25–2.33) | 0.59 (0.15–2.26) | 0.59 (0.15–2.37) |
| 25–49K | 0.27 (0.04–2.00) | 0.32 (0.02–4.66) | 0.35 (0.02–6.88) | 1.40 (0.76–2.59) | 0.75 (0.36–1.58) | 0.74 (0.35–1.59) |
| 50–74K | 0.36 (0.05–2.78) | 0.47 (0.03–7.29) | 0.47 (0.02–9.80) | 1.37 (0.82–2.29) | 1.18 (0.64–2.17) | 1.09 (0.58–2.05) |
| 75–99K | 0.27 (0.03–2.86) | 0.43 (0.02–9.56) | 0.47 (0.02–14.66) | 0.88 (0.55–1.43) | 0.73 (0.41–1.29) | 0.68 (0.38–1.23) |
| 100–150K | 0.97 (0.09–11.05) | 1.67 (0.06–46.32) | 1.97 (0.05–76.17) | 0.79 (0.53–1.19) | 0.69 (0.43–1.11) | 0.66 (0.40–1.07) |
| Prefer not to state | 0.34 (0.04–2.69) | 0.30 (0.02–4.79) | 0.26 (0.01–5.53) | 0.98 (0.59–1.62) | 0.75 (0.42–1.33) | 0.74 (0.41–1.33) |
| Self-Reported Parental Education (ref Grad School) | ||||||
| High School Graduate or Less | 0.75 (0.29–1.95) | 0.65 (0.19–2.22) | 0.69 (0.18–2.61) | 1.80 (1.07–3.03)* | 1.60 (0.85–3.03) | 1.58 (0.83–3.01) |
| College | 0.67 (0.27–1.65) | 0.80 (0.25–2.57) | 0.81 (0.23–2.86) | 1.25 (0.90–1.72) | 1.15 (0.79–1.69) | 1.18 (0.80–1.74) |
| Prefer not to state | 0.81 (0.28–2.41) | 0.59 (0.14–2.39) | 0.68 (0.15–3.17) | 1.10 (0.70–1.74) | 0.95 (0.55–1.62) | 1.05 (0.59–1.87) |
| Arthritis Subtype (ref oligoarthritis) | ||||||
| Enthesitis-related Arthritis | 9.51 (2.56–35.28)** | 7.46 (1.69–33.04)* | 9.53 (1.98–45.93)* | 8.01 (4.72–13.60)** | 4.77 (2.63–8.66)** | 4.78 (2.58–8.84)** |
| Polyarthritis (RF-) | 3.30 (1.79–6.10)** | 1.48 (0.64–3.42) | 1.45 (0.61–3.48) | 3.37 (2.38–4.78)** | 1.40 (0.88–2.22) | 1.42 (0.88–2.28) |
| Polyarthritis (RF+) | 8.15 (3.21–20.68)** | 3.91 (1.14–13.46)* | 3.57 (0.97–13.16) | 9.45 (4.87–18.34)** | 2.63 (1.19–5.81)* | 2.70 (1.21–6.06)* |
| Psoriatic Arthritis | 1.01 (0.33–3.06) | 0.57 (0.14–2.29) | 0.58 (0.13–2.67) | 2.13 (1.14–3.98)* | 1.45 (0.74–2.82) | 1.50 (0.75–3.00) |
| Undifferentiated Arthritis | 2.52 (0.65–9.68) | 2.57 (0.54–12.26) | 2.38 (0.47–12.15) | 3.91 (1.70–9.00)* | 2.49 (1.01–6.13)* | 2.62 (1.04–6.56)* |
| Active Joint Count at Enrollment (per 1 joint increase) | 1.13 (1.08–1.19)** | 1.05 (0.99–1.12) | 1.05 (0.99–1.12) | 1.11 (1.08–1.15)** | 1.05 (1.01–1.09)* | 1.05 (1.01–1.09)* |
| Physician VAS (per 1 point increase) | 1.45 (1.29–1.64)** | 1.30 (1.11–1.54)* | 1.33 (1.11–1.59)* | 1.35 (1.26–1.44)** | 1.15 (1.05–1.26)* | 1.18 (1.07–1.30)** |
| Parent/Patient VAS (per 1 point increase) | 1.27 (1.15–1.41)** | 1.13 (0.97–1.30) | 1.14 (0.97–1.33) | 1.26 (1.19–1.33)** | 1.06 (0.98–1.15) | 1.05 (0.97–1.14) |
*
p<0.05
**
p<0.001
a.
Includes all listed covariates
b.
Includes all listed covariates and site of care as random effect