TABLE 4.
Intensive treatment in last 10 cumulative exposure days and inhibitor development
| Early inhibitor development | Late inhibitor development | |||||
|---|---|---|---|---|---|---|
| N | Crude OR (95% CI) | aOR (95% CI) | N | Crude OR (95% CI) | aOR (95% CI) | |
| Surgery | ||||||
| No surgery | 135 | 1 | 1 | 67 | 1 | 1 |
| Surgery | 123 | 1.8 (1.0–3.4) | 1.8 (1.0–3.3) | 30 | 1.5 (0.5–4.6) | 1.5 (0.5–4.5) |
| Peak treatment | ||||||
| No peak treatment | 185 | 1 | 1 | 83 | 1 | 1 |
| Peak treatment | 73 | 1.8 (1.0–3.4) | 1.6 (0.8–3.0) | 14 | 4.0 (1.1–14.3) | 3.3 (0.8–13.1) |
| Mean FVIII dose | ||||||
| Low dose (≤45 IU/kg/ED) | 185 | 1 | 1 | 82 | 1 | 1 |
| High dose (>45 IU/kg/ED) | 73 | 2.8 (1.5–5.1) | 2.7 (1.4–4.9) | 15 | 4.5 (1.2–16.6) | ‐a |
Crude OR: adjusted for matching factors (year of birth in categories [<1945; 1945–1964; 1965–1987; >1987] and cumulative number of EDs in categories [1–19; 20–49; 50–99; >100]). Adjusted OR: adjusted for matching factors and predefined confounding factor. Surgery was adjusted for age at last ED (continuous variable). Peak treatment was adjusted for mean FVIII dose (continuous variable). Mean FVIII dose was adjusted for peak treatment (dichotomous variable).
Abbreviations: CI, confidence interval; ED, exposure days; FVIII, factor VIII; OR, odds ratio.
aOR for high dose could not be calculated in the late inhibitor group, because there were no control patients that received a peak treatment and a high dose.