Abstract
Iron deficiency affects 40%-50% of pregnancies. Iron is critical for early neurodevelopmental processes that are dysregulated in autism spectrum disorder (ASD). We examined maternal iron intake in relation to ASD risk in California-born children enrolled in a population-based case-control study (the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study) from 2003 to 2009 with a diagnosis of ASD (n = 520) or typical development (n = 346) that was clinically confirmed using standardized assessments. Mean maternal daily iron intake was quantified on the basis of frequency, dose, and brands of supplements and cereals consumed each month from 3 months before pregnancy through the end of pregnancy and during breastfeeding (the index period), as reported in parental interviews. Mothers of cases were less likely to report taking iron-specific supplements during the index period (adjusted odds ratio = 0.63, 95% confidence interval: 0.44, 0.91), and they had a lower mean daily iron intake (51.7 (standard deviation, 34.0) mg/day) than mothers of controls (57.1 (standard deviation, 36.6) mg/day; P = 0.03). The highest quintile of iron intake during the index period was associated with reduced ASD risk compared with the lowest (adjusted odds ratio = 0.49, 95% confidence interval: 0.29, 0.82), especially during breastfeeding. Low iron intake significantly interacted with advanced maternal age and metabolic conditions; combined exposures were associated with a 5-fold increased ASD risk. Further studies of this link between maternal supplemental iron and ASD are needed to inform ASD prevention strategies.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 890-900 |
| Number of pages | 11 |
| Journal | American Journal of Epidemiology |
| Volume | 180 |
| Issue number | 9 |
| DOIs | |
| State | Published - Nov 1 2014 |
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Keywords
- autism
- case-control studies
- child development
- dietary supplements
- iron
- pregnancy
- primary prevention
- risk factors
ASJC Scopus subject areas
- Epidemiology
- Medicine(all)
Cite this
Maternal intake of supplemental iron and risk of autism spectrum disorder. / Schmidt, Rebecca Jean; Tancredi, Daniel J; Krakowiak, Paula; Hansen, Robin L; Ozonoff, Sally J.
In: American Journal of Epidemiology, Vol. 180, No. 9, 01.11.2014, p. 890-900.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Maternal intake of supplemental iron and risk of autism spectrum disorder
AU - Schmidt, Rebecca Jean
AU - Tancredi, Daniel J
AU - Krakowiak, Paula
AU - Hansen, Robin L
AU - Ozonoff, Sally J
PY - 2014/11/1
Y1 - 2014/11/1
N2 - Iron deficiency affects 40%-50% of pregnancies. Iron is critical for early neurodevelopmental processes that are dysregulated in autism spectrum disorder (ASD). We examined maternal iron intake in relation to ASD risk in California-born children enrolled in a population-based case-control study (the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study) from 2003 to 2009 with a diagnosis of ASD (n = 520) or typical development (n = 346) that was clinically confirmed using standardized assessments. Mean maternal daily iron intake was quantified on the basis of frequency, dose, and brands of supplements and cereals consumed each month from 3 months before pregnancy through the end of pregnancy and during breastfeeding (the index period), as reported in parental interviews. Mothers of cases were less likely to report taking iron-specific supplements during the index period (adjusted odds ratio = 0.63, 95% confidence interval: 0.44, 0.91), and they had a lower mean daily iron intake (51.7 (standard deviation, 34.0) mg/day) than mothers of controls (57.1 (standard deviation, 36.6) mg/day; P = 0.03). The highest quintile of iron intake during the index period was associated with reduced ASD risk compared with the lowest (adjusted odds ratio = 0.49, 95% confidence interval: 0.29, 0.82), especially during breastfeeding. Low iron intake significantly interacted with advanced maternal age and metabolic conditions; combined exposures were associated with a 5-fold increased ASD risk. Further studies of this link between maternal supplemental iron and ASD are needed to inform ASD prevention strategies.
AB - Iron deficiency affects 40%-50% of pregnancies. Iron is critical for early neurodevelopmental processes that are dysregulated in autism spectrum disorder (ASD). We examined maternal iron intake in relation to ASD risk in California-born children enrolled in a population-based case-control study (the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study) from 2003 to 2009 with a diagnosis of ASD (n = 520) or typical development (n = 346) that was clinically confirmed using standardized assessments. Mean maternal daily iron intake was quantified on the basis of frequency, dose, and brands of supplements and cereals consumed each month from 3 months before pregnancy through the end of pregnancy and during breastfeeding (the index period), as reported in parental interviews. Mothers of cases were less likely to report taking iron-specific supplements during the index period (adjusted odds ratio = 0.63, 95% confidence interval: 0.44, 0.91), and they had a lower mean daily iron intake (51.7 (standard deviation, 34.0) mg/day) than mothers of controls (57.1 (standard deviation, 36.6) mg/day; P = 0.03). The highest quintile of iron intake during the index period was associated with reduced ASD risk compared with the lowest (adjusted odds ratio = 0.49, 95% confidence interval: 0.29, 0.82), especially during breastfeeding. Low iron intake significantly interacted with advanced maternal age and metabolic conditions; combined exposures were associated with a 5-fold increased ASD risk. Further studies of this link between maternal supplemental iron and ASD are needed to inform ASD prevention strategies.
KW - autism
KW - case-control studies
KW - child development
KW - dietary supplements
KW - iron
KW - pregnancy
KW - primary prevention
KW - risk factors
UR - http://www.scopus.com/inward/record.url?scp=84911120774&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84911120774&partnerID=8YFLogxK
U2 - 10.1093/aje/kwu208
DO - 10.1093/aje/kwu208
M3 - Article
VL - 180
SP - 890
EP - 900
JO - American Journal of Epidemiology
JF - American Journal of Epidemiology
SN - 0002-9262
IS - 9
ER -