Vitamin D levels correlate with lymphocyte subsets in elderly patients with age-related diseases

Area of Science:

• Immunology
• Endocrinology
• Geriatrics

Background:

• Hypovitaminosis D is linked to age-related diseases such as hypertension, cardiovascular disease (CRVD), cerebrovascular disease (CAD), and type 2 diabetes mellitus (T2DM).
• Vitamin D plays a role in immune function, but its specific associations with lymphocyte subsets in these conditions require further elucidation.

Purpose of the Study:

• To investigate the correlations between serum vitamin D levels (25(OH)D2 and 25(OH)D3) and lymphocyte markers (CD4, CD8, CD3, CD19).
• To explore the relationship between vitamin D status and these immune markers in elderly patients with CRVD, CAD, T2DM, and hypertension.

Main Methods:

• Retrospective observational study involving 461 healthy controls and 8,621 patients with age-related diseases.
• Flow cytometry was used to analyze lymphocyte subsets (CD4, CD8, CD3, CD19).
• Serum levels of 25-hydroxyvitamin D2 (25(OH)D2) and 25-hydroxyvitamin D3 (25(OH)D3) were measured.

Main Results:

• Over 70% of patients in each disease group exhibited vitamin D levels below 20 ng/mL.
• Specific correlations were found between vitamin D metabolites and lymphocyte markers across different disease groups (e.g., CD3/CD19 with 25(OH)D3 in CRVD; CD8/CD4/CD19/CD4:CD8 with 25(OH)D2 in CAD).
• Vitamin D deficiency was associated with increased CD8 and CD4:CD8 ratios in T2DM and hypertension patients, suggesting a Th1 lymphocyte profile induction.

Conclusions:

• Vitamin D deficiency is prevalent in elderly patients with common age-related diseases.
• Specific lymphocyte subsets show differential correlations with vitamin D levels, varying by disease type.
• The findings suggest that vitamin D deficiency may influence immune responses, potentially inducing a Th1 profile in conditions like T2DM and hypertension.