Title:The Correlation between 25-Hydroxyvitamin D Levels and Testosterone
Levels in Type 2 Diabetic Male Patients
Volume: 23
Author(s): Mohamed M. Aboelnaga*, Abdullah Nahed, Sherihan I. Gouda and Amro Elbaz
Affiliation:
- Department of Endocrinology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
Keywords:
Vitamin D, testosterone, type 2 DM, male hypogonadism, 25OH D, testosterone deficiency.
Abstract:
Background: Hypovitaminosis D and low testosterone levels are common in men with T2DM,
and vitamin D has been proposed to regulate pituitary-testicular function.
Objective: We investigated the association between testosterone levels and the circulating vitamin D
among type 2 diabetic males.
Methods: We recruited 95 males with type 2 diabetes in this cross-sectional study and investigated the
circulating form of vitamin D, which is 25-hydroxyvitamin D (25(OH) D). 25(OH) D level <30 ng/mL
was used to define vitamin D insufficiency, and 25(OH) D level <20 ng/ml was defined as a deficiency.
Testosterone deficiency was described as a total testosterone level less than 300 ng/dl.
Result: Testosterone deficiency prevalence in type 2 diabetic males was found to be 46.3%. Testosterone
deficient people with diabetes had significantly lower 25(OH) D levels than patients with normal
testosterone. We observed a higher prevalence of vitamin D deficiency in testosterone deficient people
with diabetes than testosterone sufficient patients. Furthermore, significantly lower total testosterone
levels but not LH levels were observed in diabetic males with vitamin D deficiency compared to nondeficient
patients. We observed that 25(OH) D significantly predicted total testosterone levels in diabetic
males evaluated by linear regression analysis. However, this association was no longer statistically
significant after excluding macro-albuminuric patients. Moreover, vitamin D deficiency was found to be
a significant risk factor for testosterone deficiency in logistic regression analysis.
Conclusion: Testosterone deficient males with diabetes had significantly lower 25(OH)D levels and a
higher prevalence of vitamin D deficiency than normal testosterone diabetic males. Likewise, vitamin D
deficient patients had lower testosterone levels. Overall, 25(OH) D significantly predicted total
testosterone levels. Vitamin D deficiency was thus a significant risk factor for testosterone deficiency in
diabetic males.
