Vitamin D binding protein polymorphism is associated with body weight in females.

Abstract

Objectives: Vitamin D binding protein (DBP) polymorphism has been linked to parameters related to metabolism, but the problem in hypertensive patients has not been well characterized. The current study sought to characterize the distribution of DBP phenotypes in patients diagnosed with essential hypertension, and evaluate the possible relationships with cardiovascular risk.

Methods: We studied 411 Caucasian patients with essential hypertension. DBP phenotypes were determined using polyacrylamide gel electrophoresis on serum samples. A review of clinical and laboratory measurements for each patient including blood pressure, serum lipids, and body mass index (BMI), as well as rates of diabetes diagnosis, was conducted and compared across DBP phenotypes. A matched control group (n=141) was utilized for initial comparisons.

Results: DBP phenotype distribution in the study population was consistent with Hardy-Weinberg equilibrium and parallelled the control group. We found no significant differences for systolic and diastolic blood pressure, total cholesterol, HDL, LDL, lipoprotein(a), or other demographic variables, between DBP phenotypes. Unexpectedly, DBP 2-2 phenotype was associated with a significantly higher BMI, and a greater diabetes prevalence in patients, especially in females. Notably, serum triglyceride levels in females classified as DBP 2-2 were also significantly elevated suggesting the possible metabolic consequences are gender specific.

Conclusions: DBP 2-2 phenotype appears to be linked to adverse metabolic features in hypertensive patients, particularly among women. These findings support a potential role for DBP genetic variation as a determinant of obesity and diabetes risk, highlighting the need to consider sex-specific genetic influences in metabolic syndrome risk assessments.