Vitamin D and Cognitive Impairment

Area of Science:

• Gerontology
• Nutritional Science
• Public Health

Background:

• Vitamin D deficiency is a public health concern and a potential risk factor for mild cognitive impairment (MCI).
• Existing evidence on vitamin D status and cognitive function is conflicting.
• This study investigated vitamin D status in the Thai elderly, focusing on its relationship with cognitive function, adiposity, and insulin sensitivity.

Purpose of the Study:

• To determine the prevalence of vitamin D deficiency in the Thai elderly.
• To examine the association between vitamin D status and cognitive function.
• To explore the relationship between vitamin D status, adiposity, and insulin sensitivity in this population.

Main Methods:

• The study included 718 participants aged 55-80 years from the HADThai study cohort.
• Participants were categorized into normal cognitive function or mild cognitive impairment (MCI) groups.
• Baseline data were analyzed to assess vitamin D levels, cognitive function, body composition (BMI, body fat), and insulin resistance (HOMA-IR).

Main Results:

• Vitamin D status did not significantly differ between normal cognition and MCI groups.
• Prevalence of vitamin D deficiency (<20 ng/mL) was 6.5%, and inadequacy (<30 ng/mL) was 40.0%.
• Serum 25(OH)D concentrations showed an inverse association with BMI, body fat, and HOMA-IR, but not cognitive function.

Conclusions:

• High prevalence of vitamin D inadequacy was observed in the Thai elderly population.
• Vitamin D status is inversely associated with adiposity and insulin resistance.
• The study does not support a direct role of vitamin D status in cognitive decline in this elderly cohort, but further research is warranted.