Table 1:
Characteristics of included studies in systematic review and meta analyses
| First author Year of publication | Study design | Sample size | Male % among ADHD cases | Age of ADHD cases | Infection during pregnancy | Method to confirm infection | Method to ADHD assessment | uRR (95% CI) | aRR (95% CI) |
|---|---|---|---|---|---|---|---|---|---|
| Afsharpaiman 2016 (35) | Cross sectional | 92 | 66.7% | Mean (SD): 8.12 (3.25) years | Unknown infections | questionnaire | DSM-IV-TR | 1.00 * (0.06, 16.48) | |
| Arpino 2005 (36) | Case control | 189 | 77.5% | range=6–11 years | Exanthematic infection (i.e. measles, varicella, or rubella) | questionnaire | DSM-IV-TR | 5.26 * (0.81, 34.23) †† | |
| Chudal 2019 (37) | Nested case control | 2158 | 85.4% | Mean (SD): 7.3 (1.9), range: 2–14 | Unknown infection | C-reactive protein (CRP) assayed in stored maternal sera | ICD-10 codes F90.0, F90.1, F90.8, F90.9 | 1.03 * (0.95, 1.11) | 1.05 * (0.96, 1.11) |
| Downey 2015 (38) | Cohort | 826 | 58% | range: 0–2 | Mycoplasma recovered from placenta | interview | DSM-IV-TR | 2.3 *** (1.1, 4.8) | |
| Fever | 14.83 * (4.4, 50.00) | ||||||||
| Urinary tract infection | 16.85 * (8.09, 35.07) | ||||||||
| Vaginal/cervical infection | 26.01 * (12.48, 54.22) | ||||||||
| Periodontal disease | 24.03 * (4.31, 133.76) | ||||||||
| One organism recovered from placenta | Interview | Child Behavior Checklist (CBCL)-defined attention problem † | 2.2 *** (1.3, 3.8) | ||||||
| 2+ organisms recovered from placenta | Child Behavior Checklist (CBCL)-defined attention problem † | 0.9 *** (0.5, 1.7) | |||||||
| Fever | Child Behavior Checklist (CBCL)-defined attention problem † | 14.66 * (4.68, 45.88) | |||||||
| Urinary tract infection | Child Behavior Checklist (CBCL)-defined attention problem † | 17.05 * (8.48, 34.28) | |||||||
| Vaginal/cervical infection | Child Behavior Checklist (CBCL)-defined attention problem † | 12.38 * (5.85, 26.16) | |||||||
| Periodontal disease | Child Behavior Checklist (CBCL)-defined attention problem † | 12.98 * (2.14, 156.52) | |||||||
| Ginsberg 2019 (39) | Cohort | 1066956 | 51.3% | Unknown infections | Medical records | ICD-9 code 314.00, ICD-10 code F90 | 1.03 ** (0.76, 1.41) | ||
| Gustavson 2019 (40) | Cohort | 99947 | Mean:11 range (7–17 | Fever | questionnaire | ICD-10 code F90.0 | 1.45 (1.29, 1.62 ) | 1.30 (1.15–147) | |
| Mann 2011 (21) | Cohort | 84721 | Mean: 6.49 | 71.9% | Genitourinary infections | ICD-9 codes | ICD-9 codes 314.00 314.01 | 1.12 * (1.07, 1.17) | 1.29 * (1.23, 1.35) |
| Candidiasis | 1.01 * (0.9, 1.13) | 1.22 (1.08, 1.37) | |||||||
| Chlamydia/NGU | 1.1 * (0.85, 1.43) | 1.47 (1.12, 1.92) | |||||||
| Gonorrhea | 0.83 * (0.63, 1.08) | 0.99 (0.75, 1.31) | |||||||
| Trichomoniasis | 0.97 * (0.85, 1.1) | 1.26 (1.10, 1.45) | |||||||
| Urinary tract infection | 1.17 * (1.11, 1.24) | 1.25 (1.18, 1.33) | |||||||
| genitourinary infections and preeclampsia | 1.53 * (1.32, 1.77) | ||||||||
| Mellins 2009 (47) | Cross sectional | 340 | perinatally HIV-infected | questionnaire | DSM-IV-TR | 2.45 * (1.2, 4.99) | |||
| Oerlemans 2016 (45) | Case control | 493 | Mean (SD): 11.8 (2.4), range:4–20 | 87.1% | Unknown infections | questionnaire | standardized questionnaires and diagnostic interviews | 1.41 * (0.31, 6.37) | |
| Pineda 2007 (43) | Case control | 486 | Mean (SD): 7.9 (1.5), range:6–11 | 74.5% | urinary infections along other physical illness | questionnaire | Diagnostic Interview for Children and Adolescents (DICA) and the Behavior Assessment System for Children (BASC | 4.20 * (1.70, 10.0 ) | 5.0 * (2.0, 12.9) |
| Severe maternal respiratory infection (flu) | 3.3 * (1.7, 6.4) | 3.1 * (1.5, 6.3) | |||||||
| Syphilis | 1.43 * (0.14, 13.90) | ||||||||
| Measles, Varicella, Rubella | 2.40 * (0.31, 18.35) | ||||||||
| toxoplasmosis | 1.43 * (0.14, 13.9) | ||||||||
| Schmitt 2012 (48) | Cross sectional | 13488 | Mean (SD): 9.8 (4.3), range:3–17 | 78.8% | Unknown infections along other perinatal health problems | Interview | ICD-10 hyperkinetic disorder | 1.88 * (1.6, 2.22) | 1.69 * (1.40, 2.03) |
| Silva 2014 (16) | Case control | 43062 | 77.1% | Urinary tract infection | Medical records | ICD-10 and DSM-IV-TR | 1.37 * (1.21, 1.54) for male | 1.26 * (1.11, 1.44) for male | |
| 1.51 * (1.21, 1.90) for female | 1.33 * (1.04, 1.70) for female | ||||||||
| Werenberg Dreier 2016 (22) | Cohort | 89146 | Fever | Interview | ICD-10 codes DF90.0 DF90.9 | 1.09 (0.99, 1.19) | 1.03 (0.93, 1.13) | ||
| Any infection | 1.09 ** (0.99, 1.19) | 1.01 ** (0.92, 1.11) | |||||||
| Genitourinary infections (cystitis, pyelonephritis, vaginal symptoms) | 1.22 ** (1.11, 1.34) | 1.14 ** (1.03, 1.25) | |||||||
| Persistent viral infections (orofacial herpes infection, genital herpes, condylomas) | 1.03 ** (0.91, 1.16) | 1.01 ** (0.89, 1.14) | |||||||
| Prolong Cough | 1.15 (1.03, 1.29) | 1.05 ** (0.94, 1.19) | |||||||
| Diarrhea | 1.09 (0.99, 1.20) | 0.98 ** (0.89, 1.09) | |||||||
| Other infection | 0.99 ** (0.87, 1.13) | 0.97 ** (0.84, 1.11) |
*
odds ratio
**
hazard ratio
***
risk ratio
†
outcome studied is attention problem
††
odds ratio was estimated using adding 0.5 to each cell of 2×2 contingency table