The optimal vitamin D cut-off value associated with hyperglycemia in an Iranian population

Fariba Alaei-Shahmiri; Mohammad E Khamseh; Khosro Manhoei; Hosein Yadegari; Hosein Kazemi; Majid Meshkini

doi:10.1007/s40200-019-00433-y

The optimal vitamin D cut-off value associated with hyperglycemia in an Iranian population

J Diabetes Metab Disord. 2019 Dec 10;19(1):5-12. doi: 10.1007/s40200-019-00433-y. eCollection 2020 Jun.

Authors

Fariba Alaei-Shahmiri¹, Mohammad E Khamseh¹, Khosro Manhoei², Hosein Yadegari², Hosein Kazemi², Majid Meshkini³

Affiliations

¹ Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences (IUMS), No. 10, Firouzeh St, Vali-asr St, Vali-asr Sq, Tehran, Iran.
² SAIPA Corporation, Tehran, Iran.
³ Department of Epidemiology, School of Public Health, Iran University of Medical Sciences (IUMS), Tehran, Iran.

Abstract

Background: Vitamin D deficiency may accelerate the risk of type 2 diabetes mellitus. The association of vitamin D with hyperglycemia may be influenced by lifestyle.

Objective: To evaluate the relationship between vitamin D status and hyperglycemia among the workers' population.

Methods: This was a medical records review of 7054 Iranian factory workers participating in an annual health check-up for employees. Of those, potential participants were included in this analysis if data for serum 25-hydroxyvitamin D [25(OH) D] levels were also available.

Results: Data of 429 male participants were used for this analysis. Of those, 61.07% had serum 25(OH)D concentrations lower than the sufficient level [≥20 ng/ml]. Hyperglycemic participants had significantly lower 25(OH)D than those with normal fasting blood glucose (FBG). Regression analyses highlighted serum 25(OH)D as a significant determinant of hyperglycemia [OR: 0.943(0.901, 988); p = 0.01]. The association between 25(OH)D and FBG remained significant after adjustment for potential confounders (p = 0.008). Using the ROC analysis, the serum 25(OH)D value of 14.7 ng/ml was the optimal cut-off point to predict hyperglycemia in this population (sensitivity: 63.6%, specificity: 62.3%, p = 0.01).

Conclusion: Our results revealed a considerable proportion of participants with serum 25(OH)D below the optimal level as well as a significant inverse association between vitamin D status and hyperglycemia among the factory workers. These findings highlight the importance of including the evaluation of vitamin D status as a part of annual health examinations for employees, and may help health policy- makers prevent or delay type 2 diabetes mellitus among the workers' population.

Keywords: 25(OH)D; 25-hydroxyvitamin D; Blood glucose; Cut-off point; Hyperglycemia; Vitamin D; Workers.