Children born to diabetic mothers may be more likely to have intellectual disability

Maternal smoking during pregnancy and offspring risk of intellectual disability: a UK-based cohort study

Background

Observational studies have described associations of maternal smoking during pregnancy with intellectual disability (ID) in the exposed offspring. Whether these results reflect a causal effect or unmeasured confounding is still unclear.

Methods

Using a UK-based prospectively collected birth cohort (the Avon Longitudinal Study of Parents and Children) of 13,479 children born between 1991 and 1992, we assessed the relationship between maternal smoking at 18 weeks' gestation and offspring risk of ID, ascertained through multiple sources of linked information including primary care diagnoses and education records. Using confounder-adjusted logistic regression, we performed observational analyses and a negative control analysis that compared maternal with partner smoking in pregnancy under the assumption that if a causal effect were to exist, maternal effect estimates would be of greater magnitude than estimates for partner smoking if the two exposures suffer from comparable biases.

Results

In observational analysis, we found an adjusted odds ratio for ID of 0.75 (95% CI = 0.49-1.13) for any maternal smoking and 0.97 (95% CI = 0.71-1.33) per 10-cigarette increase in number of cigarettes smoked per day. In negative control analysis, comparable effect estimates were found for any partner smoking (OR = 0.94; 95% CI = 0.63-1.40) and number of cigarettes smoked per day (OR = 0.94; 95% CI = 0.74-1.20).

Conclusions

The results are not consistent with a causal effect of maternal smoking during pregnancy on offspring ID.

Inflammatory Conditions During Pregnancy and Risk of Autism and Other Neurodevelopmental Disorders

Background

Maternal inflammation can result from immune dysregulation and metabolic perturbations during pregnancy. Whether conditions associated with inflammation during pregnancy increase the likelihood of autism spectrum disorder (ASD) or other neurodevelopmental disorders (DDs) is not well understood.

Methods

We conducted a case-control study among children born in California from 2011 to 2016 to investigate maternal immune-mediated and cardiometabolic conditions during pregnancy and risk of ASD (n = 311) and DDs (n = 1291) compared with children from the general population (n = 967). Data on maternal conditions and covariates were retrieved from electronic health records. Maternal genetic data were used to assess a causal relationship.

Results

Using multivariable logistic regression, we found that mothers with asthma were more likely to deliver infants later diagnosed with ASD (odds ratio [OR] = 1.62, 95% CI: 1.15-2.29) or DDs (OR = 1.30, 95% CI: 1.02-1.64). Maternal obesity was also associated with child ASD (OR = 1.51, 95% CI: 1.07-2.13). Mothers with both asthma and extreme obesity had the greatest odds of delivering an infant later diagnosed with ASD (OR = 16.9, 95% CI: 5.13-55.71). These increased ASD odds were observed among female children only. Polygenic risk scores for obesity, asthma, and their combination showed no association with ASD risk. Mendelian randomization did not support a causal relationship between maternal conditions and ASD.

Conclusions

Inflammatory conditions during pregnancy are associated with risk for neurodevelopmental disorders in children. These risks do not seem to be due to shared genetic risk; rather, inflammatory conditions may share nongenetic risk factors with neurodevelopmental disorders. Children whose mothers have both asthma and obesity during pregnancy may benefit from earlier screening and intervention.

The impact of maternal diabetes on the future health and neurodevelopment of the offspring: a review of the evidence

Maternal health during gestational period is undoubtedly critical in shaping optimal fetal development and future health of the offspring. Gestational diabetes mellitus is a metabolic disorder occurring in pregnancy with an alarming increasing incidence worldwide during recent years. Over the years, there is a growing body of evidence that uncontrolled maternal hyperglycaemia during pregnancy can potentially have detrimental effect on the neurodevelopment of the offspring. Both human and animal data have linked maternal diabetes with motor and cognitive impairment, as well as autism spectrum disorders, attention deficit hyperactivity disorder, learning abilities and psychiatric disorders. This review presents the available data from current literature investigating the relationship between maternal diabetes and offspring neurodevelopmental impairment. Moreover, possible mechanisms accounting for the detrimental effects of maternal diabetes on fetal brain like fetal neuroinflammation, iron deficiency, epigenetic alterations, disordered lipid metabolism and structural brain abnormalities are also highlighted. On the basis of the evidence demonstrated in the literature, it is mandatory that hyperglycaemia during pregnancy will be optimally controlled and the impact of maternal diabetes on offspring neurodevelopment will be more thoroughly investigated.

A systematic review of the biological, social, and environmental determinants of intellectual disability in children and adolescents

AIM

This systematic review aimed to identify the most important social, environmental, biological, and/or genetic risk factors for intellectual disability (ID).

METHODS

Eligible were published prospective or retrospective comparative studies investigating risk factors for ID in children 4-18 years. Exclusions were single group studies with no comparator without ID and a sample size <100. Electronic databases (Medline, Cochrane Library, EMBASE, PsycInfo, Campbell Collaboration, and CINAHL) were searched for eligible publications from 1980 to 2020. Joanna Briggs Institute critical appraisal instruments, appropriate for study type, were used to assess study quality and risk of bias. Descriptive characteristics and individual study results were presented followed by the synthesis for individual risk factors, also assessed using GRADE.

RESULTS

Fifty-eight individual eligible studies were grouped into six exposure topics: sociodemographic; antenatal and perinatal; maternal physical health; maternal mental health; environmental; genetic or biological studies. There were few eligible genetic studies. For half the topics, the certainty of evidence (GRADE) was moderate or high.

CONCLUSION

Multiple studies have examined individual potential determinants of ID, but few have investigated holistically to identify those populations most at risk. Our review would indicate that there are vulnerable groups where risk factors we identified, such as low socioeconomic status, minority ethnicity, teenage motherhood, maternal mental illness, and alcohol abuse, may cluster, highlighting a target for preventive strategies. At-risk populations need to be identified and monitored so that interventions can be implemented when appropriate, at preconception, during pregnancy, or after birth. This could reduce the likelihood of ID and provide optimal opportunities for vulnerable infants.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=120032], identifier [CRD42019120032].

Association of maternal diabetes with neurodevelopmental disorders: autism spectrum disorders, attention-deficit/hyperactivity disorder and intellectual disability

Background

Maternal diabetes has been associated with a risk of neurodevelopmental disorders (NDDs) in offspring, though the common co-occurrence of autism spectrum disorders (ASD), attention-deficit/hyperactivity disorder (ADHD) and intellectual disability (ID) is rarely considered, nor is the potential for confounding by shared familial factors (e.g. genetics).

Methods

This population-based cohort study used data from Psychiatry Sweden, a linkage of Swedish national registers, to follow 2 369 680 individuals born from 1987 to 2010. We used population-averaged logit models to examine the association between exposure to maternal type 1 diabetes mellitus (T1DM), pre-gestational type 2 diabetes mellitus (T2DM) or gestational diabetes mellitus (GDM), and odds of NDDs in offspring. Subgroup analysis was then performed to investigate the timings of GDM diagnosis during pregnancy and its effect on the odds of NDDs in offspring. We compared these results to models considering paternal lifetime T1DM and T2DM as exposures.

Results

Overall, 45 678 individuals (1.93%) were diagnosed with ASD, 20 823 (0.88%) with ID and 102 018 (4.31%) with ADHD. All types of maternal diabetes were associated with odds of NDDs, with T2DM most strongly associated with any diagnosis of ASD (odds ratio_adjusted 1.37, 95% confidence interval 1.03–1.84), ID (2.09, 1.53–2.87) and ADHD (1.43, 1.16–1.77). Considering common co-morbid groups, the associations were strongest between maternal diabetes and diagnostic combinations that included ID. Paternal T1DM and T2DM diagnoses were also associated with offspring NDDs, but these associations were weaker than those with maternal diabetes. Diagnosis of GDM between 27 and 30 weeks of gestation was generally associated with the greatest risk of NDDs in offspring, with the strongest associations for outcomes that included ID.

Conclusion

The association of maternal diabetes with NDDs in offspring varies depending on the co-morbid presentation of the NDDs, with the greatest odds associated with outcomes that included ID. Results of paternal-comparison studies suggest that the above associations are likely to be partly confounded by shared familial factors, such as genetic liability.

Taurine attenuates liver autophagy and injury of offspring in gestational diabetic mellitus rats

PURPOSE

Gestational diabetes mellitus (GDM) has many adverse effects on offspring, such as abnormal glycolipid metabolism, obesity, insulin resistance, mental retardation, schizophrenia and so on.

METHODS

We established a GDM rat model by injecting 1% streptozotocin associated with a high-fat diet one week before pregnancy, and offspring rats were sacrificed at 8 weeks of age to obtain liver tissue for study. We used hematoxylin-eosin (HE) staining to observe liver morphological changes, Tunel staining for hepatocyte apoptosis, transmission electron microscope for liver ultrastructure, and western blot for protein expression in liver tissue.

RESULTS

Compared with normal offspring rats, hepatocytes of GDM offspring rats showed obvious edema, liver organ index increased, and hepatocyte apoptosis and autophagosome in the liver were significantly increased; Bax, cleaved-caspase3/caspase3, LCII, Beclin 1, P-IKBα/IKBα and P-p65/p6 protein expression in the liver were significantly increased; Bcl2, p62 and PPARγ protein expression in the liver were significantly decreased. Tau prevented the GDM-related effects in the offspring: Tau decreased hepatocyte edema (or even disappears), liver organ index, hepatocyte apoptosis and the number of autophagosomes in the liver. In addition, Tau also decreased Bax, cleaved-caspase3/caspase3, LCII, Beclin 1, P-IKBα/IKBα and P-p65/p6 protein expression, and increased Bcl2, p62 and PPARγ protein expression in the liver of GDM offspring rats.

CONCLUSION

Taurine should be considered as a potential gestational nutritional supplement to prevent liver damage in GDM offspring.

Neurocognitive and behavioural outcomes in offspring exposed to maternal pre-existing diabetes: a systematic review and meta-analysis

AIMS/HYPOTHESIS

We performed a systematic review and meta-analysis to determine whether exposure to maternal pre-existing diabetes in pregnancy is associated with neurocognitive or behavioural outcomes in offspring.

METHODS

We searched MEDLINE, EMBASE, PsychINFO, the Cochrane Database of Systematic Reviews and Scopus for studies that examined any neurocognitive or behavioural outcomes in offspring of mothers with pre-existing diabetes in pregnancy in accordance with a published protocol (PROSPERO CRD42018109038). Title and abstract review, full-text review and data extraction were performed independently and in duplicate. Risk of bias was assessed using the Newcastle-Ottawa scale. Meta-analyses of summary measures were performed using random-effects models.

RESULTS

Nineteen articles including at least 18,681 exposed and 2,856,688 control participants were identified for inclusion. Exposure to maternal pre-existing diabetes in pregnancy was associated with a lower pooled intelligence quotient in the offspring (pooled weighted mean difference -3.07 [95% CI -4.59, -1.55]; I2 = 0%) and an increased risk of autism spectrum disorders (effect estimate 1.98 [95% CI 1.46, 2.68]; I2 = 0%). There was also an increased risk of attention deficit/hyperactivity disorder (pooled HR 1.36 [95% CI 1.19, 1.55]; I2 = 0%), though this was based on only two studies. Although most studies were found to be high quality in terms of participant selection, in many studies, comparability of cohorts and adequacy of follow-up were sources of bias.

CONCLUSIONS/INTERPRETATION

There is evidence to suggest that in utero exposure to maternal pre-existing diabetes is associated with some adverse neurocognitive and behavioural outcomes. It remains unclear what the role of perinatal factors is and the degree to which other environmental factors contribute to these findings.

Infants of Mothers With Diabetes and Subsequent Attention Deficit Hyperactivity Disorder: A Retrospective Cohort Study

Background: Maternal diabetes mellitus (DM) increases the risk of fetal, neonatal, and long-term complications in offspring. Although this has been widely known for decades, data are limited regarding the effect of maternal pregestational and gestational diabetes on the subsequent neurodevelopmental outcome of offspring. This study investigated whether infants of mothers with diabetes (IDMs) were associated with a risk of subsequent attention deficit hyperactivity disorder (ADHD). Objectives: We collected data from newborn infants born to mothers with gestational or pregestational diabetes at China Medical University Children's Hospital between January 1, 2006, and December 31, 2012. These patients were followed to evaluate their risk of ADHD (IDM group) compared with that for those born to mothers without DM (non-IDM group). Several assumed perinatal risk factors accompanying the IDMs were also analyzed. Results: Overall, 104 patients with average gestational ages of 36.5 weeks were included in the IDM group. Additionally, 110 patients with average gestational ages of 36.6 weeks were included in the non-IDM group. Compared with non-IDMs (reference), the overall risk of ADHD in IDMs was 2.6 [95% confidence interval (CI)P, 1.11-5.90; p = 0.03]. Furthermore, the risk of ADHD among male (OR, 3.78; 95% CI, 1.37-10.3; p = 0.001) and full-term infants [odds ratio (OR), 4.5; 95% CI, 1.16-17.6; p = 0.03] in the IDMs was higher than that in the non-IDM group. No significant differences were found among IDMs for the assumed perinatal risk factors that were analyzed. Conclusions: The study revealed a higher incidence rate of ADHD in IDMs, especially male and full-term infants. It is crucial for pediatricians to identify the early symptoms neurodevelopmental disorders, especially ADHD, in children of diabetic mothers to initiate proper assessment and treatment.

Oxidative Stress, Maternal Diabetes, and Autism Spectrum Disorders

Autism spectrum disorders (ASD) are a group of early-onset neurodevelopmental conditions characterized by alterations in brain connectivity with cascading effects on neuropsychological functions. To date, in the framework of an increasing interest about environmental conditions which could interact with genetic factors in ASD pathogenesis, many authors have stressed that changes in the intrauterine environment at different stages of pregnancy, such as those linked to maternal metabolic pathologies, may lead to long-term conditions in the newborn. In particular, a growing number of epidemiological studies have highlighted the role of obesity and maternal diabetes as a risk factor for developing both somatic and psychiatric disorders in humans, including ASD. While literature still fails in identifying specific etiopathological mechanisms, a growing body of evidence is available about the presence of a relationship between maternal immune dysregulation, inflammation, oxidative stress, and the development of ASD in the offspring. In this framework, results from high-fat diet animal models about the role played by oxidative stress in shaping offspring neurodevelopment may help in clarifying the pathways through which maternal metabolic conditions are linked with ASD. The aim of this review is to provide an overview of literature about the effects of early life insults linked to oxidative stress which may be involved in ASD etiopathogenesis and how this relationship can be explained in biological terms.

Preventing intellectual disability during pregnancy: what are the potentially high yield targets?

OBJECTIVE

To identify risk factors among children with unknown cause intellectual disability (ID) and to estimate the population-attributable risk (PAR) associated with these factors.

METHODS

This was a retrospective cohort study of maternal and child pairs born between 2004 and 2010 in South Carolina, and information was obtained from Medicaid billing records, birth certificates, and other administrative data. The data included 123,922 children and logistic generalized estimating equations (GEE) regression models were used to estimate the association of maternal risk factors and ID. We estimated models with and without birth weight as a covariate, since low birth weight is known to be a mediator of the association between some risk factors and ID in children.

RESULTS

The prevalence of ID in the children was 3.85% and the associations between risk factors and ID were similar for female and male children. We found that the odds of having ID were increased if a child's mother had a diagnosis of major depression; for male children, the odds ratio (OR) was 1.34 (95% confidence interval [CI] 1.14-1.59, PAR 2.17%); and for females, the OR was 1.59 (95% CI 1.30-1.95, PAR 4.70%). The odds of having ID were also increased for children of women with bipolar disorder (males - OR 1.95, 95% CI 1.53-2.48, PAR 2.85%; females - OR 1.63, 95% CI 1.20-2.22, PAR 2.05%).

CONCLUSIONS

Major maternal depression and bipolar disorder were each significantly associated with the odds of ID in children, each accounting for approximately 2-5% of the PAR, when controlling for covariates.

Prenatal, Perinatal and Neonatal Risk Factors for Intellectual Disability: A Systemic Review and Meta-Analysis

BACKGROUND

The etiology of non-genetic intellectual disability (ID) is not fully known, and we aimed to identify the prenatal, perinatal and neonatal risk factors for ID.

METHOD

PubMed and Embase databases were searched for studies that examined the association between pre-, peri- and neonatal factors and ID risk (keywords "intellectual disability" or "mental retardation" or "ID" or "MR" in combination with "prenatal" or "pregnancy" or "obstetric" or "perinatal" or "neonatal". The last search was updated on September 15, 2015. Summary effect estimates (pooled odds ratios) were calculated for each risk factor using random effects models, with tests for heterogeneity and publication bias.

RESULTS

Seventeen studies with 55,344 patients and 5,723,749 control individuals were eligible for inclusion in our analysis, and 16 potential risk factors were analyzed. Ten prenatal factors (advanced maternal age, maternal black race, low maternal education, third or more parity, maternal alcohol use, maternal tobacco use, maternal diabetes, maternal hypertension, maternal epilepsy and maternal asthma), one perinatal factor (preterm birth) and two neonatal factors (male sex and low birth weight) were significantly associated with increased risk of ID.

CONCLUSION

This systemic review and meta-analysis provides a comprehensive evidence-based assessment of the risk factors for ID. Future studies are encouraged to focus on perinatal and neonatal risk factors and the combined effects of multiple factors.