Table 4. Maternal Exposure to MF Nonionizing Radiation During Pregnancy and Risk of ADHD With or Without Immune-Related Comorbiditya.
| MF at 90th percentile | ADHD, No. (%) | aHR (95% CI)b | |
|---|---|---|---|
| Yes | No | ||
| Case definition of ADHDc | |||
| ADHD cases with asthma or AD | |||
| Low (n = 564)d | 4 (0.7) | 560 (99.3) | 1 [Reference] |
| High (n = 868)e | 35 (4.0) | 833 (96.0) | 4.57 (1.61-12.99) |
| ADHD cases without asthma and AD | |||
| Low (n = 568)d | 8 (1.4) | 560 (98.6) | 1 [Reference] |
| High (n = 847)e | 14 (1.7) | 833 (98.4) | 0.84 (0.34-2.04) |
| Persistent ADHDf | |||
| ADHD cases with asthma or AD | |||
| Low (n = 562)d | 2 (0.4) | 560 (99.6) | 1 [Reference] |
| High (n = 865)e | 32 (3.7) | 833 (96.3) | 8.27 (1.96-34.79) |
| ADHD cases without asthma and AD | |||
| Low (n = 564)d | 4 (0.7) | 560 (99.3) | 1 [Reference] |
| High (n = 844)e | 11 (1.3) | 833 (98.7) | 1.12 (0.34-3.64) |
Abbreviations: AD, atopic dermatitis; ADHD, attention-deficit/hyperactivity disorder; aHR, adjusted hazard ratio; MF, magnetic field.
a
Asthma or AD.
b
Adjusted for maternal age, race/ethnicity, educational level, prenatal smoking and alcohol use, prepregnancy body mass index, and sex of offspring.
c
Case definition of ADHD is defined as those who had 2 ADHD diagnoses at least 1 year apart.
d
The level of MF nonionizing radiation exposure is lower than 1.3 mG.
e
The level of MF nonionizing radiation exposure is 1.3 mG or higher.
f
Defined as those who continued to have ADHD diagnoses at 12 years of age or older.