Evaluation of calcium level in patients with diabetes mellitus according to the examination in the mobile medical center (Diamodule)
Authors:   Endocrinology Research Centre, Moscow, Russia, Zheleznyakova Anna V. , Volodicheva Victoriya L. ,   Endocrinology Research Centre, Moscow, Russia, Vikulova Olga K. ,   Endocrinology Research Centre, Moscow, Russia, Serkov Alexey A. ,   Endocrinology Research Centre, Moscow, Russia, Eremkina Anna K. ,   Endocrinology Research Centre, Moscow, Russia, Shestakova Marina V. ,   Endocrinology Research Centre, Moscow, Russia, Mokrysheva Natalia G. ,   Endocrinology Research Centre, Moscow, Russia
Published: July 2021

Background. Diabetes mellitus (DM) is characterized by multiple risk factors for the combined development of disorders of phosphorus-calcium metabolism, due to more frequent overweight, decreased renal filtration function and vitamin D deficiency in this category of patients. Aim. To assess the level of calcium in blood serum and its correlations with parameters of carbohydrate metabolism, body mass index (BMI) and renal function in patients with type 1 and type 2 diabetes. Materials and methods. The object of the study: adult patients with type 1 diabetes (T1DM) and type 2 diabetes (T2DM) ≥18 years old who underwent examination in Diamodule (n=294) in 2019 in the Voronezh region, who were additionally tested for serum calcium. The examination at the mobile medical center includes: assessment of anthropometric data (height, weight, BMI), biochemical data of blood lipids and creatinine levels with calculation of glomerular filtration rate (GFR-EPI), albuminuria and the albumin/creatinine in a single portion of urine, measurement of glycated hemoglobin (HbA1c), blood pressure, electrocardiogram, consultation with a cardiologist, ophthalmologist, specialist of the Diabetic Foot office, diabetologist. All biochemical parameters was carried out using commercial kits on a biochemical express analyzer Spotchem EZ ArkraySP-4430. Determination of HbA1c, albuminuria, albumin/creatinine was performed by immunochemical method on a DCA Vantage analyzer. Data analysis was carried out using the Statistica v.13.3 software package (TIBCO Software Inc., USA). The results are presented as medians and quartiles [25; 75], the level of reliability is taken as p<0.05. Results. Hypocalcemia (serum calcium level less 2.15 mmol/L) was detected in 88.3% of patients with T1DM and 73.6% of patients with T2DM. The level of serum calcium in T1DM was 1.96 [1.83; 2.07], in T2DM – 2.04 [1.97; 2.16] (p<0.001) with significant differences in GFR: in T1DM 69.6 [57.8; 82.5], with T2DM 50.5 [44.1; 59.9] (p<0.001). We observed correlation between GFR and calcium level r=-0.3 (p<0.05,). GFR<60 ml/min/1.73 m² was observed in 30.5% of T1DM patients, in 75.0% of T2DM. The HbA1c in T1DM was 8.7% [7.7; 9.8], in T2DM – 8.3% [6.8; 9.4] (p=0.01). Obesity was revealed in T1DM in 12.3%, in T2DM in 71.4%; the median BMI in T1DM was 25.5 kg/m2 [21.9; 28.4], in T2DM – 33.2 kg/m2 [29.7; 37.9]. There was correlation between BMI and calcium level r=0.26 (p<0.05). Conclusion. The results of the study revealed a high prevalence of hypocalcemia among patients with diabetes, the most pronounced in type 1 diabetes. In the presence of a correlation between calcium and GFR, there was a high incidence of hypocalcemia in patients with T1DM, even in the absence of a significant decrease in GFR, which may indicate to additional risk factors. Since the assessment of the level of calcium is not included in the list of standard clinical examination, it is recommended to include this parameter and conduct regular screening in risk groups, which include patients with diabetes. More extensive research is needed to analyze the factors.