Table 2.
Risk of adverse pulmonary events among patients treated with valproic acid or phenytoin
| Number (%) of events in valproic acid treated patients | Number (%) of events in phenytoin treated patients | Unadjusted hazard ratio (95% CI)* | Adjusted hazard ratio (95% CI)* | |
|---|---|---|---|---|
| Primary outcome | ||||
| Hospital admission or emergency room visit for COPD | 175 (3.8%) | 373 (4.4%) | 0.81 (0.68 – 0.98) | 1.00 (0.79 – 1.27) |
| Tracer outcome | ||||
| Cataract surgery | 91 (2.0%) | 188 (2.2%) | 0.83 (0.64 – 1.07) | 0.79 (0.57 – 1.09) |
*
Reference group is individuals treated with phenytoin. Models adjusted for propensity score, age, sex, Charlson co-morbidity score, residence in long-term care facility, number of prescription drugs in previous year, xanthine use, stroke/transient ischemic attack, seizure disorder and lung malignancy.