ABSTRACT

The aim of this study was to evaluate the relationship between hemoglobin A1c (HbA1c) and 25-hydroxyvitamin D levels and to investigate the difference in this relationship between genders.

In this study, we retrospectively evaluated fasting blood glucose, HbA1c, 25-hydroxyvitamin D and parathyroid hormone levels in 3675 subjects (660 male, 3015 female). The subjects were divided into two groups according to sex and into three groups according to HbA1c levels as pre-diabetics (5.7-6.4%), diabetics (6.5-8.0%) and uncontrolled diabetics (>8.1%). Individuals with an HbA1c value between 4.0% and 5.6% who had no history of diabetes mellitus constituted the control group.

Significantly low levels of 25-hydroxyvitamin D were detected in female uncontrolled diabetics (p<0.001). However, no difference found in males between the groups A downward trend in 25-hydroxyvitamin D levels was observed to start in prediabetes period. There was no significant difference in parathyroid hormone levels between the groups.

In addition to HbA1c levels, 25-hydroxyvitamin D levels should be investigated and considered especially in follow-up of diabetic female patients.