Table 5.
Crude and Adjusted Odds Ratios (ORadj) and 95% Confidence Intervals (CIs) for Autism Spectrum Disorders (ASDs) Associated With Selected Organism Specific Infections, Kaiser Permanente Northern California Childhood Autism Perinatal Study, 1995 – 1999
| Exposure* | ASD Cases (N = 407) n(%) |
Controls (N=2075) n (%) |
Crude OR (95% CI) | ORadj**(95% CI) |
|---|---|---|---|---|
| Unexposed group*** | 199 (48.9) | 1080 (52.0) | reference | reference |
| Bacterial Infection | ||||
| 30 Days Pre Conception | 6 (1.5) | 35 (1.7) | 0.93 (0.39–2.24) | 0.89 (0.36 – 2.20) |
| Pregnancy period1 | 67 (16.5) | 292 (14.1) | 1.24 (0.92–1.69) | 1.31 (0.96 –1.80) |
| 1st Trimester | 12 (2.9) | 69 (3.3) | 0.94 (0.50–1.77) | 0.95 (0.49 – 1.84) |
| 2nd Trimester | 20 (4.9) | 61 (2.9) | 1.78 (1.05–3.01) | 1.71 (0.99 – 2.96) |
| 3rd Trimester | 45 (11.1) | 186 (8.9) | 1.31 (0.92–1.88) | 1.42 (0.98 – 2.06) |
| Viral infection | ||||
| 30 Days Pre Conception | 2(0.5) | 11 (0.5) | - | - |
| Pregnancy period1 | 40 (9.8) | 184 (8.9) | 1.18 (0.81–1.71) | 1.15 (0.78 – 1.68) |
| 1st Trimester | 5 (1.2) | 45 (2.2) | 0.60 (0.24–1.54) | 0.63 (0.24 – 1.65) |
| 2nd Trimester | 12 (2.9) | 57 (2.7) | 1.14 (0.60–2.17) | 1.06 (0.55 – 2.04) |
| 3rd Trimester | 27 (6.6) | 104 (5.0) | 1.41 (0.90–2.21) | 1.35 (0.85 – 2.15) |
| Mycoses Infection | ||||
| 30 Days Pre Conception | 4 (0.9) | 10 (0.5) | - | - |
| Pregnancy period1 | 32 (7.8) | 116 (5.6) | 1.50 (0.98–2.28) | 1.53 (0.98 – 2.96) |
| 1st Trimester | 9 (2.2) | 33 (1.6) | 1.48 (0.70–3.14) | 1.56 (0.71 – 3.41) |
| 2nd Trimester | 11 (2.7) | 40 (1.9) | 1.49 (0.75–2.96) | 1.46 (0.71 – 2.98) |
| 3rd Trimester | 14 (3.4) | 48 (2.3) | 1.58 (0.86–2.92) | 1.64 (0.87 – 3.10) |
| Unknown Infection | ||||
| 30 Days Pre Conception | 22 (5.4) | 79 (3.8) | 1.51 (0.92–2.48) | 1.42 (0.84 – 2.39) |
| Pregnancy period1 | 142 (34.9) | 690 (33.3) | 1.15 (0.88–1.41) | 1.16 (0.91 – 1.48) |
| 1st Trimester | 61 (15.0) | 312 (15.0) | 1.06 (0.77–1.45) | 1.14 (0.81 – 1.58) |
| 2nd Trimester | 55 (13.5) | 259 (12.5) | 1.15 (0.83–1.60) | 1.22 (0.87 – 1.72) |
| 3rd Trimester | 64 (15.7) | 290 (14.0) | 1.20 (0.89–1.63) | 1.22 (0.89 – 1.68) |
*
Maternal infections diagnosed during an inpatient hospitalization or outpatient clinic visit during pregnancy.
**
All ORs were adjusted for the matching variables (child sex, year of birth and hospital of birth) in addition to maternal age and race/ethnicity.
***
The unexposed group had no diagnosed infections during the period from 30 days before pregnancy to delivery.
1
The pregnancy period is defined as the time between the LMP and the date of delivery.