Impact of prenatal alcohol exposure on intracortical myelination and deep white matter in children with attention deficit hyperactivity disorder

Cobalamin Status Among Patients with Fetal Alcohol Spectrum Disorder (FASD)-A Preliminary Study

Background/Objectives: Fetal alcohol spectrum disorders comprise a range of neurodevelopmental disorders caused by prenatal alcohol exposure. Recent investigations have revealed that among patients with neurodevelopmental disorders, serum cobalamin (vitamin B12) levels are substantially higher than those of healthy controls. Patients with fetal alcohol spectrum disorders similarly present with higher levels of cobalamin, yet the significance of cobalamin in the pathogenesis of fetal alcohol spectrum disorders remains to be established. This study aimed to examine cobalamin and other cobalamin status markers in patients with fetal alcohol spectrum disorders in comparison with healthy controls. Methods: In total, 80 patients were enrolled in the study-41 diagnosed with fetal alcohol spectrum disorders and 39 healthy controls. The diet history method was used to assess vitamin B12 intake for three days preceding blood sampling. Total vitamin B12 (cobalamin), holotranscobalamin, methylmalonic acid and soluble transcobalamin receptor (CD320) were measured in serum samples. Results: The daily intake of vitamin B12 was higher in patients with fetal alcohol spectrum disorders compared to controls, both in the simple analysis and after adjusting for age (OR for patients with FASDs: 1.82; 95% CI: 1.16-2.87). An elevated serum cobalamin level was noted in some patients from the group with fetal alcohol spectrum disorders. No statistically significant differences were found between the groups in serum levels of cobalamin, holotranscobalamin, CD320 or methylmalonic acid. However, the correlations between cobalamin and its metabolites differed in fetal alcohol spectrum disorders as compared to those in the control group. Conclusions: Our study did not find any deficits of vitamin B12 and its metabolites in patients with fetal alcohol spectrum disorders. Further studies to investigate the role of vitamin B12 in the pathogenesis of fetal alcohol spectrum disorders should be established given the fact that both high and low levels of vitamin B12 may have negative health impacts.

Exploring Nutritional Status and Metabolic Imbalances in Children with FASD: A Cross-Sectional Study

BACKGROUND/OBJECTIVES

Malnutrition is a significant concern in paediatric populations, particularly among children with neurodevelopmental disorders such as foetal alcohol spectrum disorder (FASD). This study aimed to examine macronutrient and micronutrient imbalances and assess the nutritional status of a group of patients with FASD.

METHODS

This study involved an analysis of the serum levels of key nutrients in a group of children diagnosed with FASD. Macronutrients and micronutrients were measured to identify any imbalances, including vitamin D, B12, E, A, albumin, and serum protein, among others.

RESULTS

The study found a high prevalence of vitamin D deficiency among the patients. Additionally, elevated serum concentrations of micronutrients such as vitamin B12, E, and A were observed in 8%, 7%, and 19% of patients, respectively. Macronutrient imbalances were noted, including high levels of albumin and serum protein, indicating a possible metabolic disturbance. Unexpectedly, high rates of hypercholesterolemia were observed, raising concerns about an increased risk of metabolic syndrome in this population.

CONCLUSIONS

These findings suggest that the principal issue among patients with FASD is an altered metabolism rather than nutritional deficiencies. Potential causes of these abnormalities could include oxidative stress and changes in body composition. The results underline the need for further research to better understand the unique nutritional challenges in children with FASD and to guide the development of targeted therapeutic strategies.

Mediating role of obesity on the association between disadvantaged neighborhoods and intracortical myelination

We investigated the relationship between neighborhood disadvantage (area deprivation index [ADI]) and intracortical myelination (T1-weighted/T2-weighted ratio at deep to superficial cortical levels), and the potential mediating role of the body mass index (BMI) and perceived stress in 92 adults. Worse ADI was correlated with increased BMI and perceived stress (p's<.05). Non-rotated partial least squares analysis revealed associations between worse ADI and decreased myelination in middle/deep cortex in supramarginal, temporal, and primary motor regions and increased myelination in superficial cortex in medial prefrontal and cingulate regions (p<.001); thus, neighborhood disadvantage may influence the flexibility of information processing involved in reward, emotion regulation, and cognition. Structural equation modelling revealed increased BMI as partially mediating the relationship between worse ADI and observed myelination increases (p=.02). Further, trans-fatty acid intake was correlated with observed myelination increases (p=.03), suggesting the importance of dietary quality. These data further suggest ramifications of neighborhood disadvantage on brain health.

Associations between moderate alcohol consumption, brain iron, and cognition in UK Biobank participants: Observational and mendelian randomization analyses

BACKGROUND

Brain iron deposition has been linked to several neurodegenerative conditions and reported in alcohol dependence. Whether iron accumulation occurs in moderate drinkers is unknown. Our objectives were to investigate evidence in support of causal relationships between alcohol consumption and brain iron levels and to examine whether higher brain iron represents a potential pathway to alcohol-related cognitive deficits.

METHODS AND FINDINGS

Observational associations between brain iron markers and alcohol consumption (n = 20,729 UK Biobank participants) were compared with associations with genetically predicted alcohol intake and alcohol use disorder from 2-sample mendelian randomization (MR). Alcohol intake was self-reported via a touchscreen questionnaire at baseline (2006 to 2010). Participants with complete data were included. Multiorgan susceptibility-weighted magnetic resonance imaging (9.60 ± 1.10 years after baseline) was used to ascertain iron content of each brain region (quantitative susceptibility mapping (QSM) and T2*) and liver tissues (T2*), a marker of systemic iron. Main outcomes were susceptibility (χ) and T2*, measures used as indices of iron deposition. Brain regions of interest included putamen, caudate, hippocampi, thalami, and substantia nigra. Potential pathways to alcohol-related iron brain accumulation through elevated systemic iron stores (liver) were explored in causal mediation analysis. Cognition was assessed at the scan and in online follow-up (5.82 ± 0.86 years after baseline). Executive function was assessed with the trail-making test, fluid intelligence with puzzle tasks, and reaction time by a task based on the "Snap" card game. Mean age was 54.8 ± 7.4 years and 48.6% were female. Weekly alcohol consumption was 17.7 ± 15.9 units and never drinkers comprised 2.7% of the sample. Alcohol consumption was associated with markers of higher iron (χ) in putamen (β = 0.08 standard deviation (SD) [95% confidence interval (CI) 0.06 to 0.09], p < 0.001), caudate (β = 0.05 [0.04 to 0.07], p < 0.001), and substantia nigra (β = 0.03 [0.02 to 0.05], p < 0.001) and lower iron in the thalami (β = -0.06 [-0.07 to -0.04], p < 0.001). Quintile-based analyses found these associations in those consuming >7 units (56 g) alcohol weekly. MR analyses provided weak evidence these relationships are causal. Genetically predicted alcoholic drinks weekly positively associated with putamen and hippocampus susceptibility; however, these associations did not survive multiple testing corrections. Weak evidence for a causal relationship between genetically predicted alcohol use disorder and higher putamen susceptibility was observed; however, this was not robust to multiple comparisons correction. Genetically predicted alcohol use disorder was associated with serum iron and transferrin saturation. Elevated liver iron was observed at just >11 units (88 g) alcohol weekly c.f. <7 units (56 g). Systemic iron levels partially mediated associations of alcohol intake with brain iron. Markers of higher basal ganglia iron associated with slower executive function, lower fluid intelligence, and slower reaction times. The main limitations of the study include that χ and T2* can reflect changes in myelin as well as iron, alcohol use was self-reported, and MR estimates can be influenced by genetic pleiotropy.

CONCLUSIONS

To the best of our knowledge, this study represents the largest investigation of moderate alcohol consumption and iron homeostasis to date. Alcohol consumption above 7 units weekly associated with higher brain iron. Iron accumulation represents a potential mechanism for alcohol-related cognitive decline.