Table 2.
Odds of Having an Infection during the First Three Years of Life and during the Neonatal Period by Case Status (ASD vs. POP controls and ASD vs. DD controls)
| Caregiver interviews | ASD (n = 699) n (%) | POP (n = 980) n (%) | Crude OR (95% CI) | Adjusted ORa (95% CI) |
|---|---|---|---|---|
| Ever infection | 359(51.4) | 396(40.4) | 1.56(1.36–1.79)e | 1.66(1.47–1.87)e |
| Age of infectionb | ||||
| Never infection | 340(49.3) | 584(60.0) | REF | REF |
| Infection only in first year of life | 72(10.4) | 71(7.3) | 1.74(1.11–2.74)e | 1.76(1.14–2.71)e |
| Infection only in second year of life | 45(6.5) | 65(6.7) | 1.19(0.60–2.34) | 1.35(0.67–2.74) |
| Infection only in third year of life | 40(5.8) | 56(5.7) | 1.23(1.01–1.50)e | 1.32(1.14–1.53)e |
| Infection during multiple time periods | 193(28.0) | 198(20.3) | 1.67(1.45–1.94)e | 1.78(1.57–2.02)e |
| Neonatal records | ASD (n = 594) | POP (n = 771) | Crude OR (95% CI) | Adjusted ORa (95% CI) |
| Ever infectionc | 29(4.9) | 17(2.2) | 2.28(1.25–4.16)e | 1.80(1.12–2.90)e |
| Low temperature | 9(1.5) | 2(0.3) | 5.92(1.90–18.44)e | 6.30(1.65–24.08)e |
| High temperature | 20(3.4) | 24(3.1) | 1.08(0.84–1.41) | 1.29(0.90–1.87) |
| Caregiver interviews | ASD (n = 699) | DD (n = 766) | Crude OR (95% CI) | Adjusted ORa (95% CI) |
| Ever infection | 359(51.4) | 386(50.4) | 1.04(0.82–1.32) | 1.05(0.83–1.33) |
| Age of infectionb | ||||
| Never infection | 340(49.3) | 380(49.6) | REF | REF |
| Infection only in first year of life | 72(10.4) | 73(9.5) | 1.10(0.72–1.69) | 1.17(0.77–1.77) |
| Infection only in second year of life | 45(6.5) | 47(6.1) | 1.07(0.74–1.54) | 1.08(0.67–1.76) |
| Infection only in third year of life | 40(5.8) | 34(4.4) | 1.31(0.84–2.07) | 1.44(0.88–2.37) |
| Infection during multiple time periods | 193(28.0) | 232(30.3) | 0.93(0.80–1.08) | 0.90(0.79–1.04) |
| Neonatal records | ASD (n = 594) | DD (n = 594) | Crude OR (95% CI) | Adjusted ORa (95% CI) |
| Ever infectiond | 29(4.9) | 25(4.2) | 1.17(0.92–1.48) | 1.46(1.05–2.03)e |
| Low temperature | 9(1.5) | 3(0.5) | 3.03(0.94–9.81) | 2.88(0.83–10.05) |
| High temperature | 20(3.4) | 28(4.7) | 0.70(0.49–1.01) | 0.70(0.47–1.03) |
Abbreviations: ASD = Autism spectrum disorder; POP = General population; DD = Non-ASD developmental delays or disorders; OR = Odds ratio.
All models adjusted for child sex, maternal education, maternal race/ethnicity, and maternal age at birth, and accounted for correlation by enrollment site.
Age of infection is a five-level variable; OR’s are calculated separately for each age category, comparing children in that category to those who never had an infection; age of infection missing for 9 ASD, 0 DD, and 6 POP children.
Additional adjustment for: Child birthweight.
Additional adjustment for: Family income and child’s gestational age.
Statistically significant.