TABLE 3

Incidence of Opioid-Related Adverse Events According to Age Category, Timing of Use, Days Since Prescription Filled, and Dose Tertile

Prescription Exposure Period, dN CasesIncidence per 100 000 dIRRa95% CI
Age category, y
 12–179 380 2213103.32.221.67–2.96
 6–115 303 297711.30.940.66–1.33
 2–53 997 444561.4Reference
Timing of use
 Current5 048 6472635.22.091.58–2.76
 Recent13 632 3151741.3Reference
Days since prescription filled, d
 1–33 339 6522296.93.312.41–4.53
 4–74 203 526872.11.511.13–2.02
 ≥811 137 7841211.1Reference
Dose (mg/kg per d) tertile
 High6 075 0311772.91.861.45–2.39
 Intermediate6 426 7591602.51.591.23–2.04
 Low6 179 1721001.6Reference
  • —, not applicable.

  • a The Poisson regression model for adjusted IRRs includes age (2–5, 6–11, and 12–17 years), sex, current versus recent use, days since the prescription fill (1–3, 4–7, and ≥8), dose tertile by age, and calendar year (1999–2003, 2004–2007, and 2008–2011). Current use was defined as the time between the filling of the prescription and the end of the days of supply. Recent use was defined as the additional 14 days after the end of the days of supply.