Neuronal Biomarkers and Micronutrient Status in Adults with Mild Cognitive Impairment
Background: Mild cognitive impairment (MCI) represents an intermediate state between normal cognitive ageing and dementia. Given the increasing dementia burden in the country, there is a critical need for early detection through the assessment of MCI. However, studies that comprehensively examined the associations between micronutrients, neuronal markers, and cognitive impairment are scarce. Methods: A community-based cross-sectional study was conducted among 184 adults aged 55–85 years in Hyderabad between January 2024 and March 2025. Sociodemographic, anthropometric, biochemical, nutritional, and neuronal biomarkers were estimated. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) tool. Results: The study reported an MCI prevalence of 36.4% among older adults, significantly associated with higher HbA1c and systolic blood pressure, and elevated neuronal markers such as β-Amyloid, T tau, and Nfl. Vitamin D, B1, B2, B6, and B9 levels were significantly lower in the MCI group, with a higher burden of deficiency. Higher vitamin levels were correlated with better MoCA scores and a lower predicted probability of MCI, especially vitamins D and B6. In particular, B2 and B6 have shown associations with BDNF, tau, and Nfl markers. Conclusions: Lower levels of circulatory vitamins were significantly associated with a higher probability of MCI. Also, neuronal biomarkers were significantly associated with micronutrient deficiencies. These findings suggest that micronutrient deficiencies may be associated with MCI in older adults, highlighting the potential importance of maintaining adequate micronutrient status to support healthy cognitive aging and possibly reduce the risk of dementia. However, given the cross-sectional design of the present study, causal relationships cannot be established. Future longitudinal studies are warranted to validate these associations and further clarify the temporal relationship between micronutrient status and cognitive decline.