Correlation of thiamine metabolite levels with cognitive function in the non-demented elderly

Thiamine metabolism is critical for glucose metabolism and also vital for brain function, which is susceptible to decline in the elderly. This study aimed to investigate whether thiamine metabolites correlate with cognitive function in the non-demented elderly and their impact factors. Volunteers >60 years old were recruited and their blood thiamine metabolites and Mini-Mental State Examination (MMSE) scores were measured. The apolipoprotein E (APOE) genotype, routine blood parameters, liver and kidney function, and levels of fasting blood glucose and triglycerides were also measured. The results showed that the thiamine diphosphate (TDP) level weakly correlated with MMSE score in the non-demented elderly. Participants with high TDP levels performed better in Recall and Attention and Calculation than those with low TDP. TDP levels were associated with the APOE ε2 allele, body mass index, hemoglobin level, fasting blood glucose, and triglycerides. Our results suggest that TDP, which is easily affected by many factors, impacts cognitive function in the elderly.