Relation Of Vitamin D Level With Glycemic Status In Type2 Diabetes Mellitus

Abstract

Worldwide the Prevalence of Diabetes Mellitus (DM) has increased dramatically in last two decades, from 30 million cases in 1985 to 415 million in 2017. International Diabetes Federation (IDF) predicts that 642 million people will have DM by the year 2040 (1). Few studies have demonstrated the inverse relationship between serum vitamin D level and prevalence of type 2 DM (2), and by supplementing vitamin D the incidence of DM can be decreased (3).

Full text

10289 Afr. J. Biomed. Res. Vol. 27, No.4s (December) 2024 Dr Meghanad Meher et al.
https://africanjournalofbiomedicalresearch.com/index.php/AJBR
Afr. J. Biomed. Res. Vol. 27(4s) (December 2024); 10289-10292
Research Article
Relation Of Vitamin D Level With Glycemic Status In Type2
Diabetes Mellitus
Dr Subhash Chandra Dash1, Dr Sourabh Pradhan2, Dr Soumya Ranjan Pradhan3,
Dr Meghanad Meher4*, Dr Sankalp Gupta5
1Professor, department of general medicine, IMS and Sum Hospital Bhubaneswar ,Soa(Deemed to be
university), Odisha. drsubhashdash73@gmail.com
2MD Medicine, Assistant professor, Medicine department, IMS and Sum Hospital Bhubaneswar. SOA
deemed to be University, Bhubaneswar, Odisha. sourabhpradhan@soa.ac.in
3Assistant professor department of general medicine IMS and Sum Hospital Bhubaneswar ,SoaDeemed to be
university, Odisha. drsoumya016@gmail.com
4Assistant professor department of general medicine IMS and sum hospital (SOA Deemed to be university),
Bhubaneswar Odisha India,megha.hrt@gmail.com,9439275371
5Senior Resident, Dept. of Gastroenterology Sr Kalla Memorial Gastroenterology & General Hospital, Jaipur.
drguptasankalp@gmail.com
*Corresponding Author: Dr Meghanad Meher
*Assistant professor department of general medicine IMS and sum hospital (SOA Deemed to be university),
Bhubaneswar Odisha India,megha.hrt@gmail.com,9439275371
Receive- 01/12/2024 Acceptance -24/12/2024
DOI: https://doi.org/10.53555/AJBR.v27i4S.5653
© 2024 The Author(s).
This article has been published under the terms of Creative Commons Attribution-Noncommercial 4.0 International
License (CC BY-NC 4.0), which permits noncommercial unrestricted use, distribution, and reproduction in any medium
provided that the following statement is provided. “This article has been published in the African Journal of Biomedical
Research.”
Introduction
Worldwide the Prevalence of Diabetes Mellitus (DM)
has increased dramatically in last two decades, from 30
million cases in 1985 to 415 million in 2017.
International Diabetes Federation (IDF) predicts that
642 million people will have DM by the year 2040 (1).
Few studies have demonstrated the inverse relationship
between serum vitamin D level and prevalence of type
2 DM (2), and by supplementing vitamin D the
incidence of DM can be decreased (3).
Vitamin D is mainly produced in the skin by the effect
of sunlight on 7- Dehydrocholesterol (4). Vitamin D
plays a important role not only in musculoskeletal
system, but also in cellular proliferation and
differentiation and immune system modulation (5).
Vitamin D decreases insulin resistance probably by its
effect on calcium and phosphorus metabolism and by
upregulation of insulin receptor gene (6). Different
mechanisms are suggested to associate the role of
Vitamin D with occurrence of DM. Some of these are
location of Vitamin D receptors in the beta cells of
Pancreas, expression of Vitamin D response element in
human insulin gene, improvement of insulin mediated
glucose utilization following Vitamin D therapy, effect
of cytokines like Interleukin 6 and Tumour Necrosis
factor alpha (TNF alpha) in giving rise to insulin
resistance and inhibition of cytokine production by
Vitamin D (7 -10). Serum 25- Hydroxy- Vitamin D,
(25 (OH) D) level is the most specific screening test for
Vitamin D deficiency (11).
Only a few studies are done in India to establish a
relation of Vitamin D level with glycemic status in
Type 2 DM. So this study was picked up.

Relation Of Vitamin D Level With Glycemic Status In Type2 Diabetes Mellitus
10290 Afr. J. Biomed. Res. Vol. 27, No.4s (December) 2024 Dr Meghanad Meher et al.
Materials & Methods
This cross-sectional observational study was conducted
in the Department of Medicine, IMS & SUM Hospital,
Bhubaneswar over a period of 12 months. Diagnosed
case of type 2 diabetes mellitus patients of more than
18 years of age, attending to the Outpatient Department
of Medicine during January 2023 to December 2023
were included in the study. Patients with liver disease,
renal disease, malignancy, metabolic bone disorders
and patients on vitamin D supplementations,
anticonvulsants or steroids were excluded from the
study. Details of the study was explained to the
participants and written informed consent was obtained
before participation. Thus, a total of 110 subjects were
included in the study.
Detailed history and thorough clinical examination
were done in all patients. Demographic data, all clinical
details and biochemical parameters were recorded in a
structured format. Blood sample was taken in the
morning after overnight fasting. Blood sugar was
measured by hexokinase method. Glycosylated
hemoglobin (HbA1c) was measured by high
performance liquid chromatography (HPLC) method.
HbA1c of < 7% was referred to as good glycemic
control (1). Serum 25(OH) D was estimated by electro-
chemiluminescent immunoassay (ECLIA) method by
automated analyzer (Cobas e 411).
All the data were analyzed by using statistical package
SPSS, version 20.0. Data were first analyzed for
normal distribution by Kolmogorov- Simrinov test, Q-
Q Plot and Histogram. Numbers and percentages were
used for categorical variables and mean with standard
deviation, median and range for continuous variables.
Based on serum 25(OH)D levels, participants were
grouped into vitamin D sufficiency (vitamin D level of
≥30ng/ml), insufficiency (vitamin D level of 20-
29.9ng/ml) and deficiency (vitamin D level of
<20ng/ml) groups. Chi-Square test for categorical
variables and ANOVA tests for continuous variables
were used for comparison between the groups. Vitamin
D status was also compared between patients with
HbA1c of < 7% and HbA1c of ≥ 7%. Chi-Square test
for categorical variables and Independent ‘t’ for
continuous variables were used for comparison
between the two groups. Pearson test was used to
correlate serum vitamin D level with HbA1c levels.
Two-tailed p-value of <0.05 was considered as
statistically significant.
Results
Mean age of the participants was 59.18 ±11.6 years and
40.9% (n=45) were female. The mean duration of
diabetes in the participants was 7.8 ±4.5 years and
median duration was of 7years. The mean HbA1c was
8.5 ±4.2%. The mean serum vitamin D level was 17.8
±8.5ng/ml. According to the serum 25(OH)D level,
participants were grouped into Vitamin D sufficient
(8.2%, n=9), insufficient (25.5%, n=28) and deficient
(66.4%, n=73) groups. Other characteristics of the
participants are described in Table1.
Demographic characteristics and other parameters were
compared among the vitamin D status groups (table 2).
There was no difference in sex distribution, age, body
mass index (BMI) and waist circumference (WC)
across the groups (p=0.165, p=0.503, p=0.204 and
p=0.222, respectively). The median duration of
diabetes was not significantly different among the
groups (7 years vs. 7 years vs. 6 years, p=0.078).
However, the mean HbA1c was found significantly
higher in patients with vitamin D deficiency and
insufficiency (8.8 ±2.4% vs. 8.4 ±2.5% vs. 6.3±1.1%,
p=0.011). The mean fasting blood sugar (FBS) levels
were also significantly higher in patients with vitamin
D deficiency and insufficiency (186.4 ± 60.2 vs 166.4±
51.9 vs 132.6 ± 44.1, p=0.018).
Serum vitamin D level was also compared with
glycemic control (HbA1c <7% vs. HbA1c ≥7%) and
found to have significant difference (p=0.004). Further,
frequencies of vitamin D deficiency, insufficiency and
sufficiency were also compared between glycemic
control groups. Among diabetic patients with poor
glycemic control 74.6% (n=59) were having vitamin D
deficiency as compared to 45.1% with good glycemic
status, which was statistically significant (p=0.003)
(Table3). Serum 25(OH)D levels were also correlated
with HbA1c levels but found to have no statistically
significant correlation (r = -0.176, p=0.066).
Table 1. Baseline parameters of study participants (n=110)
Parameters
Mean ± SD
Median (IQR)
% (n)
Age in years
59.18 ±11.6
Female gender
40.9 (45)
BMI in kg/m2
25.3 ±2.8
WC in cm
97.4 ±8.0
SBP in mmHg
138.6 ±17.7
140 (130-150)
DBP in mmHg
82.3 ±8.8
80 (76-90)
Duration of DM in years
7 (5-9)
HbA1C in %
8.5 ±4.2
FBS in mg/dl
176.9 ±58.7
Hypertension
30 (33)
S. Vit.D level ng/ml
17.8 ±8.5
Vit.D deficiency
66.4 (73)
Vit.D insufficiency
25.5 (28)
Vit.D sufficiency
8.2 (9)

Relation Of Vitamin D Level With Glycemic Status In Type2 Diabetes Mellitus
10291 Afr. J. Biomed. Res. Vol. 27, No.4s (December) 2024 Dr Meghanad Meher et al.
Table 2. Comparison of demographic and clinical parameters among Vit.D status groups
Characteristics
Vit. D deficiency
(n=73)
Vit.D insufficiency
(n=28)
Vit.D sufficiency
(n=9)
P value
Female sex % (n)
43.8 (32)
42.8 (12)
11.1 (1)
0.165
Age in years
59.8±11.6
56.9±12.4
60.4±8.0
0.503
BMI in kg/m2
25.1±2.7
25.3±3.2
26.9±2.6
0.204
WC in cm
98.3±8.6
95.4±6.9
95.7±5.0
0.222
FBS in mg/dl
186.4±60.2
166.4±51.9
132.6±44.1
0.018
HbA1C
8.8±2.4
8.4±2.5
6.3±1.1
0.011
Median duration of
DM in years
7
7
6
0.078
Table 3. Relation of Glycemic status with Vit.D status
Vit.D status
HbA1C <7%
(n=31)
HbA1C ≥7%
(n=79)
P vaue
S. Vit.D level ng/ml (Mean±SD)
21.5±10.9
16.3±7.0
0.004
Vit.D deficiency % (n)
45.1 (14)
74.6 (59)
0.003
Vit.D Insufficiency % (n)
32.2 (10)
22.7 (18)
0.305
Normal Vit.D % (n)
22.5 (7)
2.5 (2)
0.001
Discussion
In our study the mean HbA1c was found significantly
higher in patients with vitamin D deficiency and
insufficiency (8.8 ±2.4% vs. 8.4 ±2.5% vs. 6.3±1.1%,
p=0.011).
In National Health and Nutrition Examination Survey
(NHANES 2003 – 2006), 9773 adults were
participated. Cross-sectional analysis of the data was
done. It was evident that serum 25(OH) D
concentration was inversely associated with HbA1c
level in 35–74 years old individuals (12). Similarly Yu
et al. reported that in T2 DM patients high levels of
HbA1c were independently associated with Vitamin D
deficiency (13). Athanassiou et al also found an inverse
relationship between vitamin D levels and HbA1C. In
T2DM cases, the vitamin D values were observed to be
19.26 +/- 0.95 ng/ml, which were in the Insufficiency
range (14). Anderson et al noticed high prevalence of
DM in persons with severe vitamin D deficiency (15).
Sabherwal et al found a significant decrease in HbA1C
levels in south- Asian T2DM patients after vitamin D
administration, which signifies a role of vitamin D in
glycemic control (16). Nikooyeh et al also noticed
improvement in glycemic control (decrease in HbA1C
level) after administration of vitamin D in T2DM
patients (17).
In our study the mean fasting blood sugar (FBS) levels
were significantly higher in patients with vitamin D
deficiency and insufficiency (186.4±60.2 vs 166.4±
51.9 vs 132.6 ±44.1, p=0.018). A cross-sectional
Finnish study similarly observed inverse correlation
between vitamin D levels and Fasting Insulin, Fasting
Glucose and 2hour glucose tolerance results (18).
Mauss et al also noticed severe vitamin D deficiency
was associated with high Fasting blood sugar and
T2DM (19).
But Yiu et al found no significant change in HbA1C
level after supplementation of Vitamin D in T2DM
patients (20). Kumar A et al also found no significant
association between vitamin D and glycemic control
(21).
The possible mechanisms by which the glycemic status
in diabetic patients could be influenced by vitamin D
include: improvement in insulin sensitivity and beta
cell survival, protection of beta cells against cytokine
induced apoptosis (22), and increased insulin secretion
from beta cells of pancreas (23).
Being a cross-sectional study, our study cannot
establish the cause and effect relationship. Large
intervention trials involving vitamin D supplementation
in T2DM patients are required to provide further
evidence regarding the benefit of vitamin D
supplements in improving the glycemic status.
Conclusion
We conclude that the serum HbA1C level and Fasting
blood sugar level are significantly higher in Type 2
Diabetes Mellitus patients with Vitamin D Deficiency
or Insufficiency, as compared to Type 2 DM patients
with normal vitamin D level.
CONFLICTS OF INTEREST
There are no conflicts of interest.
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