Table 3.
Crude and Adjusted Incidence Rate Ratios for Serious Infections by Individual Opioids Among Tennessee Medicaid Enrollees (1995–2015)
| Opioid Type | Infections During Current Use (n) | Incidence per 100 Person-years of Current Use | Crude IRR (95% CI) |
Spline-adjusted IRRa (95% CI) |
IPTW-adjusted IRRb (95% CI) |
|||
|---|---|---|---|---|---|---|---|---|
| Opioids with previously recognized immunosuppressive properties | ||||||||
| Morphine | 459 | 2.91 | 1.00 | (reference) | 1.00 | (reference) | 1.00 | (reference) |
| Fentanyl | 501 | 8.95 | 3.08 | (2.71, 3.50) | 1.06 | (0.88, 1.28) | 0.89 | (0.73, 1.08) |
| Methadone | 52 | 2.30 | 0.79 | (0.59, 1.06) | 0.83 | (0.61, 1.13) | 0.82 | (0.60, 1.11) |
| Opioids without previously recognized immunosuppressive properties | ||||||||
| Oxycodone | 179 | 2.84 | 0.98 | (0.82, 1.16) | 0.73 | (0.60, 0.89) | 0.72 | (0.59, 0.87) |
| Oxymorphone | 19 | 1.17 | 0.40 | (0.25, 0.64) | 0.95 | (0.58, 1.56) | 1.05 | (0.56, 1.97) |
Abbreviations: CI, confidence interval; IPTW, inverse-probability of treatment weighting; IRR, incidence rate ratio.
aAdjusted for cubic spline of the propensity score for treatment with each opioid, cubic spline of the cumulative opioid dose, and cubic spline of age and calendar year (2-year intervals).
bAdjusted for cubic spline of the cumulative dose, cubic spline of age, calendar year (2-year intervals), and using IPTW with the propensity score for treatment with each opioid.