Analysis of vitamin D deficiency in patients with type 2 diabetes mellitus

Abstract

Objective To analyze the serum level of 25-hydroxy vitamin D3 and the degree of vitamin D deficiency in the patients with type 2 diabetes mellitus,and the relationships between the degree of vitamin D deficiency,durations of diabetes and glycosylated hemoglobin A1c (HbA1c) levels were also investigated.Methods 140 patients with type 2 diabetes mellitus (60 male and 80 female) were selected from the Department of Endocrinology of The General Hospital of Tianjin Medical University,aged 21 to 89,with an average age of (58.25 ± 13.76) years old.Serum 25-hydroxy vitamin D3 levels between different age groups (＜50,≥ 50 and ＜70,≥70years old group) and tested season groups (winter and spring,summer and autumn group),different duration of diabetes groups (＜ 10,≥ 10 and ＜20,≥ 20 years group) and different HbA l c level groups (＜ 7％,≥7％ and＜ 10％,≥ 10％) were compared.Results (1)The serum 25(OH)D3 levels of these 140 patients were all below normal range,and the average levels was (40.07 ± 16.12) nmol/L.The prevalence of severe vitamin D deficiency,deficiency and sufficiency were 13.57％,67.86％ and 4.29％,respectively.But there was no significant difference between male and female both in the serum 25(OH)D3 levels and the degree of vitamin D deficiency(t =0.803,x2=0.189,both P ＞0.05).(2) The serum 25(OH)D3 levels of patients aged ≥ 50 and＜70 were lower than that of the subjects aged ＜50 in male (F =2.362,P ＜0.05).In female,the serum 25 (OH)D3 levels of patients aged ≥ 50 were lower than that of the subjects aged ＜50 (F =3.928,P ＜ 0.05),and the percentages of vitamin D deficiency were also greater than that in patients younger than 50 years (x2=10.036,P ＜0.01).(3)The serum 25(OH)D3 levels in winter and spring were lower than that in summer and autumn (t =-4.681,P ＜0.01),and the percentage of severe vitamin D deficiency and deficiency were increased as well (x2=18.202,P ＜ 0.01).(4)The serum 25(OH)D3 levels in patients whose durations of diabetes were more than 10 years were lower than that of patients with diabetic duration less than 10 years (F =5.489,P ＜0.05,P ＜0.01),and the percentage of severe vitamin D deficiency in patients whose durations were more than 20 years was higher than that of patients with diabetic duration less than 10 years (x2=7.284,P ＜0.05).(5)The serum 25 (OH)D3 levels in patients whose HbA l c were more than 7％ were lower than those with HbAlc lower than 7％(F =3.963,P ＜0.01),and the percentages of severe vitamin D deficiency and deficiency were higher than that of patients with HbAlc lower than 7％ as well (x2=6.712,P ＜0.05).Conclusion Vitamin D deficiency is common in patients with type 2 diabetes,especially in patient with long durations and continuously poor blood glucose control.The assessment and supplement of vitamin D should be strengthened in patients with diabetes especially in winter. Key words: 25-Hydroxy vitamin D3; Vitamin D deficiency; Vitamin D insufficiency; Diabetes mellitus