Table 2

HRs and 95% CIs comparing the risk for ADHD in exposed and unexposed children by timing and type of antipsychotic exposure

Number with ADHD/NPerson-years at riskHazard ratio (95% CI)
CrudeModel 1*Model 2†
Antipsychotic exposure
 Unexposed71775/4 308 62041 863 3391.00 (Reference)1.00 (Reference)1.00 (Reference)
 Exposed anytime during pregnancy482/15 466130 2112.28 (2.08 to 2.49)2.00 (1.83 to 2.19)1.10 (1.00 to 1.21)
Timing of antipsychotic exposure
 First trimester only210/647856 1442.17 (1.90 to 2.49)1.72 (1.51 to 1.97)1.07 (0.93 to 1.23)
 Second/third trimester only103/334928 5342.24 (1.84 to 2.72)2.09 (1.72 to 2.54)1.08 (0.89 to 1.32)
 First trimester and second/third trimester169/563945 5342.45 (2.10 to 2.85)2.46 (2.11 to 2.85)1.06 (0.90 to 1.25)
Type of antipsychotic exposure
 Typical antipsychotics only272/689675 1791.84 (1.63 to 2.08)1.71 (1.51 to 1.93)1.11 (0.98 to 1.26)
 Atypical antipsychotics only166/775248 1003.11 (2.67 to 3.62)2.40 (2.06 to 2.79)1.00 (0.85 to 1.17)
  • *Adjusted for source country, birth year, sex of child, maternal age, and parity.

  • †Adjusted for source country, birth year, sex of child, maternal age, parity, maternal education, cohabitation, mother born within source country, BMI, smoking, maternal comorbidity, use of known teratogens, use of suspected teratogens, other medications during pregnancy.

  • ADHD, attention-deficit/hyperactivity disorder; BMI, body mass index; CI, confidence interval; HR, hazard ratio.