A comparison of the effects of parental risk markers on pre- and perinatal variables in multiple patient cohorts with fetal alcohol syndrome, autism, Tourette syndrome, and sudden infant death syndrome: an enviromic analysis.

The prevalence and magnitude of effect of individual risk markers for specific developmental disorders vary widely across diagnostic category. The four study cohorts for this project were patients from four diagnostic registries in North Dakota for fetal alcohol syndrome (FAS), autism, sudden infant death syndrome (SIDS), and Tourette syndrome. These four cohorts were used to estimate prevalence and magnitude of effect of parental risk markers in patients with developmental disabilities. Cases with North Dakota birth certificates were matched with controls. Using birth certificate data, we then examined five parental risk markers for each cohort and estimated direct and indirect effects for each risk marker by cohort. The authors found two significant paternal risk markers (age in SIDS and education in FAS). Significant maternal markers were age in SIDS, education in FAS, autism, and SIDS. Marital status was a significant risk marker in FAS. Effect sizes were estimated using paired t tests, odds ratios, and population attributable risk (PAR) for both direct and indirect effects for each marker. We estimated both direct and indirect effects to allow for direct comparisons of the differential effect estimates of each of these markers. The direct effect of parental markers differs across diagnostic cohorts of patients. Use of cohorts from similar denominator populations obtained from prevalence studies is a useful methodological tool for estimating the prevalence and magnitude of effect of risk markers.