| ADHD medication use | Person- years |
Events | Rate/100,000 person-years |
Hazard Ratio† |
95% confidence interval |
|---|---|---|---|---|---|
| Nonuser | 1,597,962 | 49 | 3.07 | 1.00 | Reference |
| Former user | 607,475 | 25 | 4.12 | 1.03 | 0.57–1.89 |
| Current User | 373,667 | 7 | 1.87 | 0.75 | 0.31–1.85 |
| Methylphenidate | 192,257 | 4 | 2.08 | 0.96 | 0.31–2.97 |
| Amphetamines‡ | 137,448 | 1 | 0.73 | - | - |
| Atomoxetine‡ | 29,330 | 1 | 3.41 | - | - |
| Pemoline‡ | 14,632 | 1 | 6.83 | - | - |
†
Hazard ratios estimated with Cox regression models which included site-specific propensity score decile, site, medical conditions (serious cardiovascular disease, serious chronic illness), psychiatric conditions (major psychiatric illness, substance abuse, and antipsychotic use), utilization variables (medical hospitalization and general medical care access), age, and calendar year.
‡
Because of low numbers of events for use of amphetamines, atomoxetine, and pemoline, regression models were not fit for these individual medications.