European Journal of Cardiovascular Medicine

The number of persons with diabetes is expected to rise significantly in India, where the incidence of Type 2 diabetes mellitus (T2DM) is rising at an alarming rate [1]. The most prevalent metabolic disease is this one. Type 1 and type 2 diabetes mellitus were distinguished in 1936, however the condition was first documented in Egyptian writings 3,000 years ago [2,3].

Globally, urban areas will account for the majority of the anticipated population growth between 2000 and 2030 [1]. By 2030, there will be 366 million diabetics worldwide, up from 171millionin 2000 [4].

A collection of metabolic disorders with many etiologies, diabetes mellitus is characterized by persistently elevated blood sugar levels and involves abnormalities in the metabolism of fats, proteins, and carbohydrates brought on by the action and synthesis of insulin [5].

Insulin is an anabolic hormone that alters the metabolism of minerals, lipids, carbohydrates, and many other compounds. Depending on the cause of diabetes mellitus, low insulin secretion, decreased glucose utilization, and increased glucose synthesis are all factors that lead to hyperglycemia [6,7]. India is expected to have 101.2 million diabetes patients by 2030, up from 62.4 million in 2011, according to the ICMR INDIA [8].

Most diabetics in poor nations are between the ages of 45 and 64, whereas most diabetics in industrialized nations are older than 64.[9] Over 82 million individuals in underdeveloped nations and over 48 million in industrialized nations are predicted to have diabetes by the year 2030 [9].

Type 1 diabetes mellitus, type 2 diabetes mellitus, and gestational diabetes mellitus are the three categories typically used by the American Diabetes Association [10].

In 1988, the main element of metabolic syndrome was identified as type 2 diabetes mellitus. It was predicted that 366 million individuals would have diabetes mellitus in 2011; by 2030, that figure is estimated to have increased to 552 million [11,12].

Type 2 diabetes, another name for non-insulin-dependent diabetes mellitus, is characterized by high blood sugar (hyperglycemia), insulin resistance, and perhaps an insulin shortage [13].

Hyperglycemia brought on by the increasing failure of pancreatic cells in the context of chronic insulin resistance is a hallmark of diabetes mellitus 2, an endocrine illness [14]. It has been demonstrated in experiments that calcium and vitamin D enhance peripheral insulin sensitivity and pancreatic beta-cell activity, while low vitamin D levels are linked to indicators of insulin resistance [16] and poor glucose metabolism [14,15]. In recent decades, it has been demonstrated that calcium and vitamin D homeostasis are necessary for insulin resistance and secretion [17]. The beta-cell must receive calcium in order for the calcium-dependent mechanism of insulin production to occur [17, 18].

Insulin's ability to decrease phosphate was identified as soon as insulin preparations were made accessible [19]. Phosphorus plasma concentration and the level of metabolic regulation in diabetes are closely related [20–24].

Analyzing blood calcium, serum phosphorous, and vitamin D levels in patients with type 2 diabetes mellitus and in healthy individuals, as well as evaluating the relationship between these parameters, was the primary goal of this study.

This was a hospital based prospective cross-sectional study  between case and control group conducted in Department of Biochemistry and Physiology Department at a Tertiary care Centre, Uttar Pradesh. A Total of 100 patients were included in this study and divided into two groups.

Group1: (CASE GROUP) consist of 50 patients with type -2 Diabetes mellitus.

Group 2: (CONTROL GROUP) consists of healthy individuals.

Inclusion criteria: Patients above aged above 20 years having type-2 diabetes mellitus.

Exclusion criteria: Patients with other complications like Chronic liver disease, Pregnant women, heavy smokers, patients taking drugs like isoniazid, rifampicin and patients on vitamin-D therapy were excluded from this study.

Sample collection: Five millilitres of blood were drawn from the antecubital vein under aseptic conditions following an overnight fast in both the fasting and postprandial states. Three millilitres of blood were placed in a plane vial, allowed to coagulate to extract the serum, and then centrifuged for ten minutes at 3000 rpm. The centrifuged sample was then used to measure the levels of calcium, phosphorous, and 25-hydroxyvitamin-D.

To check the fasting blood sugar level, the remaining 2 millilitres of blood were transferred into an EDTA vial. Two hours following the meal, the postprandial blood glucose level was assessed.

Serum 25(OH) D was estimated with the ELISA method [21]. Estimation of serum calcium was done with Arsenazo 111 method/ cresalphthalein complexions method [22]. Estimation of serum phosphorus with Molybdate U. V. method [23] FPG and 2-h PPPG were measured using enzymatic methods (GOD-POD) [24].

Statistical analysis: The data were analyzed with excel software version 12. Values of P < 0.05 were assumed to be significant (P < 0.05). Pearson correlation coefficients were calculated to assess the relationships between serum calcium, phosphorus, and vitamin D levels.

A total of 100 individuals which were divided into two groups were studied. Group I (CASE GROUP): include diabetic patients (n=,50) in which males were 33(66%) and females were 17(34%). Their ages were observed between 20 to 80 years. (Table 1 and Table 2).

The maximum number of diabetic patients were found in the age group of 61-70 (30%)  followed by 27.5% were found in the age group of 51-60 and only 5% of diabetic patients were found in the age group of 20-30. In group 2 (CONTROL GROUP): there were 42(84%)were females and 8(16%) were males. Among them the 10(25%) of individuals were belong to age group 61-70 while only 3 (7.5%) were belong to age group 31-40. (Table 1 and Table 2).

Table 1: Comparison of Gender between healthy individuals and diabetic patients.

In this table it was observed that, 66% and 34% males and females were diabetic respectively.

Table 2: Comparison of Age between control group and diabetic patients.

From the Table No. 2 it was observe that, maximum number of diabetic patients were from the age group between 40-70 years. This age group was also similar with the control group.

The serum phosphorous level was higher in diabetic patients than in healthy individuals. In diabetic patients, 39(78%) individuals have phosphorous level <3.4mg/dl while 8(16%) individuals have phosphorous level is in normal range between 3.5 to 4.5mg/dl and only one patient have phosphorous level > 4.5mg/dl. As shown in table3.

Table 3: Comparison of Serum Phosphorous level between Diabetic patients and in control groups.

In this table it was observed that, serum phosphorous level was less than normal range in diabetic patients which include 78% of individuals while 84% healthy individuals show serum phosphorous level in normal range.

The serum calcium level in diabetic patients (n=40) was found to be less than the healthy individuals. Among diabetic patients, 17(34%) individuals have serum calcium level less than 8.4mg/dl. While 26(52%) individuals have serum calcium level is in between normal range which is 8.5-10.5mg/dl and only 3(6%) individuals have serum calcium level >10.5mg/dl. Comparison of serum calcium level between diabetic patients and healthy individuals is given in table 4.

Table 4: Comparison of Serum calcium level between diabetic patients and control group.

In this table it was observed that, 100% healthy individuals have serum calcium level is in the normal range. While in diabetic group, 34% individuals shows calcium level <8.4mg/dl.

In this study it was observed that the deficiency of vitamin-D level in diabetic patients was quite low as only 9(18%) of diabetic patients shows vitamin-D deficiency. Comparison of vitamin-D level among healthy and diabetic patients was shown in Table 5.

Table 5: Comparison of Serum 25-hydroxy Vitamin-D level between diabetic patients and control group.

In this table it was observed that, only 18% of diabetic patients were less concentration of Vitamin-D level.

   Graph: 1:  Bar Chart showing frequency distribution of HbA1C, Seum Calcium, Phosphorus and Vit-D levels among Cases

Graph 2:  Bar Chart showing frequency distribution of HbA1C, Seum Calcium, Phosphorus and Vit-D levels among Control group

In the current  study the HbA1C versus Serum Calcium was studied where  Chi²  : 8.11, P-value:  0.017 which was observed to be statistically significant. The result for  HbA1C versus Serum Phosphorus was found to be Chi ²  : 5.79,  P-value:  0.059 which was noted to be statistically  significant.

The result for HbA1C versus Serum Vit-D Chi ²  :11.07,  P-value:  0.017 which was observed to be statistically  significant.

Diabetes mellitus is a metabolic disorder. It is a group and various degrees of carbohydrate, lipid and protein metabolism impairment [25] .

Diabetes mellitus can have a variety of causes and etiologies, but it usually involves aberrant insulin secretion & response at some point throughout the disease's evolution. Type 1 diabetes (autoimmune diabetes) and type 2 diabetes mellitus are the two most frequent types of diabetes mellitus both are characterized by hyperglycemia, insulin resistance and relative insulin shortage [13].

In our study the ratio of most diabetic patients were observed to be male (66%) as compared to the  females (34%). The diabetes mellitus was seen most prevalent in the age group of  40-70 years. Our study was in  correlated with the study conducted by  other author Qadri et al in year 2017, where  most patients were male and higher diabetic prevalence were seen in the age group of 30-60 years and patients suffering from diabetes mellitus female patients were about 22% of the total [ 26]. While study by Marwa et al.  was in constrast to the present study where that prevalence of T2DM in females was found to be 63% than males, i.e., 37% [27].

In our study, it was observed that the comparison of age between control group and diabetic group were in the age group of 21-70 years. There were no significant changes in the age group of controls and case group.

In present study, we compared serum calcium level in control groups and diabetic patients, the serum calcium level in diabetic patients were low as compared to control groups (healthy individuals). There were 34% diabetic patients shows decreased in calcium level. This correlates with the study conducted by Qadri et al, where they recorded that the mean value of serum calcium (7.98±0.91 mg/dl) in diabetes patients were significantly (p<0.001) decreased when compared with prediabetes patients (8.53±0.84 mg/dl) [ 26].

It was observed that that the serum phosphorous level in diabetic patients were significantly low as compared to healthy individuals, in our study, 78% diabetic patients were shown <3.4mg/dl serum phosphorous level. This study is significant with P-value:  0.059.(p<0.001).

The study done by Kanchana N, et al. 2014 [28] observed that serum level of calcium with the mean value of (9.4±0.38 mg/dl) was significantly decreased in type 2 diabetes mellitus patients then controls and also found a negative correlation between fasting plasma glucose and serum calcium concentration, that prove increased glucose levels was associated with decreased calcium levels.

While study by Nigah, et al.Serum calcium levels in patients were found to be in the range of 7.20–11.40 mg/dl, while the range of serum calcium concentration in the healthy individuals under study was 7.0–10.80 mg/dl. Thus, serum calcium concentration was significantly lower in patients as compared to controls [ 29].

Serum phosphorus levels in patients were found to be in the range of 2.8–6.0 mg/dl, whereas the range of serum phosphorus concentration in the healthy individuals understudy was 2.4–10.80 mg/dl. Thus, serum phosphorus concentration was also comparatively lower in patients as compared to controls with P value 0.001 at (P < 0.05) [29] and was observed to be statistically significant.

In our study, the vitamin-D level in both diabetic group and control group were in the normal range. There is no correlation between vitamin -D and type-2 diabetes mellitus. The studies conducted by Nigah et al[29 ] showed that Vitamin D deficiency was more frequent in T2DM females 79.7% than males 71.2% this finding confirmed by Arif et al. 2017 who reported that T2DM female were four times more prone for Vitamin D deficiency than males 151 (79%) and 40 (21%), respectively.[30] Vitamin D levels of patients were found to be in the range of 2.25–55.13 while that of controls were in the range of 1.51–71.0 ng/ml which slightly varies from a study conducted by Bayani et al., in which mean concentration of Vitamin D in the case group was 18.7 ± 10.2 and in the control group was 24.6 ± 13.5 ng/dl [31].

Diabetes mellitus (DM) has affected over 387 million patients globally, expected to reach 592 million by the end of 2035. It is a metabolic disorder characterized by chronic hyperglycemia caused by either insulin deficiency, insulin resistance, or both [32,33].

Deficiencies in vitamin D have been associated with reduced insulin production and insulin resistance, both of which play crucial roles in the progression of diabetes due to their influence on calcium homeostasis. Several variables, including less time spent in the sun, altered food, and metabolic changes,contribute to the low vitamin D levels seen in diabetics. The need for careful monitoring and management of vitamin D and calcium levels in people with diabetes to improve their metabolic health [34,35].

This study concluded that, there is a significant correlation in serum calcium, serum phosphorous and vitamin-D level among diabetic patients and control groups. Hence, these parameters should be considered in early detection of type-2 diabetes mellitus among individuals.

This study highlights the strong correlations between person with type 2 diabetes and serum levels of vitamin D, calcium, and phosphorus. These findings suggest that addressing vitamin D deficiency and ensuring mineral metabolism is in balance may help control type 2 diabetes more effectively overall. Additional longitudinal research is required to examine the underlying mechanisms and associated connections since glycemia may be impacted by the declining levels of serum calcium, phosphorus, and vitamin D.

DECLARATIONS

Conflicts of interest: There is no any conflict of interest associated with this study

Consent to participate: We have consent to participate.

Consent for publication: We have consent for the publication of this paper.

Authors' contributions: All the authors equally contributed the work.

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