Table 3.
Comparisons of the incidence of hyponatremia among the tramadol/acetaminophen extended-release, tramadol/acetaminophen immediate-release, and acetaminophen groups
| PSM model | No. of subjects | Observ.period (person-days) | No. of events | IR per 1000 person-days |
|---|---|---|---|---|
| Na < 135 mM | ||||
| Extended release | ||||
| AA | 2364 | 25,006 | 112 | 4.479 |
| TA | 2364 | 24,482 | 211 | 8.619 |
| Immediate release | ||||
| AA | 3337 | 35,334 | 157 | 4.443 |
| TA | 3337 | 35,196 | 200 | 5.682 |
| Na < 130 mM | ||||
| Extended release | ||||
| AA | 2364 | 25,664 | 12 | 0.468 |
| TA | 2364 | 25,652 | 24 | 0.936 |
| Immediate release | ||||
| AA | 3337 | 36,309 | 15 | 0.413 |
| TA | 3337 | 36,219 | 22 | 0.607 |
PSM propensity-score matched, Observ. observation period, No. number of events, IR incidence rate, AA acetaminophen, TA tramadol/acetaminophen