World Rural Health Conference
Home Print this page Email this page Small font size Default font size Increase font size
Users Online: 180
Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents 
ORIGINAL ARTICLE
Year : 2018  |  Volume : 7  |  Issue : 6  |  Page : 1314-1318  

Evaluation of HbA1C and serum levels of vitamin D in diabetic patients


1 Department of Cardiology, Ilam University of Medical Sciences, Ilam, Iran
2 Biotechnology and Medical Plants Research Center, Ilam University of Medical Sciences, Ilam, Iran
3 Medical Student, Ilam University of Medical Sciences, Ilam, Iran
4 Department of Pathology, Clinical Research Development Center, Shahid Modarres Hospital, Shahid Beheshti University of Medical Science, Tehran, Iran

Date of Web Publication30-Nov-2018

Correspondence Address:
Dr. Mohammad Reza Hafezi Ahmadi
Biotechnology and Medical Plants Research Center, Ilam University of Medical Sciences, Ilam
Iran
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jfmpc.jfmpc_73_18

Rights and Permissions
  Abstract 


Background: Diabetes mellitus is the most common metabolic disease around the world. The present study aims at studying hemoglobin A1C (HbA1C) and vitamin D serum levels in diabetic patients. Materials and Methods: A descriptive study was conducted on 102 diabetic patients presenting to the diabetic clinic of a tertiary care hospital in West of Iran in 2016 (Shahid Mostafa Khomeini Hospital of Ilam city). The data collected were inserted into the SPSS-20 software, and it was then analyzed by using the relevant statistical tests. For describing the quantitative variables, mean and standard deviation were used. Moreover, for describing the qualitative variables, number and percentage were applied. The mean serum levels of HbA1C and vitamin D were compared for different variables using the Chi-square and ANOVA. Results: There is a positive and statistically significant relationship between the HbA1C and fasting blood sugar (FBS). Moreover, there is a statistically significant relationship between the serum level of vitamin D with smoking and body mass index (BMI). There is also an inverse linear relationship between vitamin D with HbA1C, FBS, BMI, and disease duration. The relationship between HbA1C with FBS and disease duration is a linear direct one. Their relationship between HbA1C and BMI is an inverse linear one, yet not significant. Conclusion: Given the role of this vitamin in secretion and the effect of insulin, it seems useful to monitor the serum level of vitamin D in a diabetic patient and prescribe its supplements if necessary.

Keywords: Diabetic patients, hemoglobin A1C, Ilam, serum levels of vitamin D


How to cite this article:
Ghavam S, Ahmadi MR, Panah AD, Kazeminezhad B. Evaluation of HbA1C and serum levels of vitamin D in diabetic patients. J Family Med Prim Care 2018;7:1314-8

How to cite this URL:
Ghavam S, Ahmadi MR, Panah AD, Kazeminezhad B. Evaluation of HbA1C and serum levels of vitamin D in diabetic patients. J Family Med Prim Care [serial online] 2018 [cited 2018 Dec 13];7:1314-8. Available from: http://www.jfmpc.com/text.asp?2018/7/6/1314/246519




  Introduction Top


Diabetes mellitus is the most common metabolic disease in the world. More than 150 million people suffer from this disease in the world, and it is predicted that this number will rise to 300 million in 2025.[1] Iran is facing an increasing prevalence of diabetes, and its prevalence is currently 7% in Iran.[2] Vitamin D is an indispensable part of nutrition. In comparison to the other vitamins, vitamin D has unique metabolic and physiological effects.[3],[4],[5],[6],[7] The shortage of vitamin D is epidemically prevalent in the world; 20–25% of the population suffers from the lack of vitamin D in USA, Canada, Europe, Mexico, Asia, and Australia.[8] Surprisingly, the lack of vitamin D in the Persian Gulf countries is highly prevalent, though there is enough sunshine. The prevalence of vitamin D (serum level of vitamin D) deficiency is higher among female adolescents and young adults in Iran and >80% in Saudi Arabia.[9]

The lack of vitamin D and type 2 diabetes have similar risk factors including race, obesity, high age, place of residence, and lack of physical activity. In a number of studies, it has been observed that 25-hydroxyvitamin D serum level is significantly lower in diabetic patients than healthy individuals.[10],[11],[12] Vitamin D affects the production and secretion of insulin as well as insulin sensitivity.[13] Vitamin D is also likely to affect reduced risk[14],[15],[16],[17] and control type 2 diabetes.[11],[14] Given the increasing prevalence of type 2 diabetes and shortage of vitamin D, it is important to study this relationship. For this reason, various studies have been conducted all over the world on this issue.

For the incidence of type 2 diabetes, there is an increased performance of pancreatic beta cells, resistance to insulin, and systemic inflammation. There is evidence indicating the effects of vitamin D on the abovementioned complications.[18] Vitamin D is likely to indirectly affect insulin secretion and insulin sensitivity through beta cells and environmental tissues that are the targets of insulin. The immunomodulatory features of vitamin D in relation to T cells activity is effective for some immune processes leading to type 1 diabetes.[19]

Different studies have indicated the relationship between the lack of vitamin D and concentration changes of blood glucose and insulin and the sensitivity of tissues targeted for insulin.[20],[21] Moreover, the lack of vitamin D in patients suffering from type 2 diabetes is likely to cause a metabolic syndrome and the replacement of vitamin D can reduce resistance to insulin.[22] Some of the studies have confirmed that vitamin D plays a key role in insulin secretion and performance disorder.[23] A number of cross-sectional studies have indicated the coincidence of vitamin D status and the prevalence of impaired glucose tolerance (IGT) or diabetes. Two studies conducted by Kohert in America and a study conducted in Finland have reported the coincidence of vitamin D status and the risk of suffering from type 2 diabetes.[24],[25] In women's health study, receiving 511 units of vitamin D, in comparison to 159 units, is likely to result in a reduced risk of suffering from type 2 diabetes. However, this analysis has not been modified for any other intervention factors other than age.[24] There is a significant statistical coincidence between high serum levels of vitamin D and low incidence of diabetes in Finnish men.[25] Another study conducted in New Zealand indicated that patients with type 2 diabetes and IGT had a lower level of vitamin D in comparison to the control group.[26] There is a hypothesis indicating that there is a positive relationship between 25-hydroxyvitamin D serum level and obesity. Given the effect of vitamin D on increased lipogenesis and lipolysis control in the in vitro studies conducted, some researchers have reported this relationship as positive.[27] However, other studies conducted in this regard indicated the negative effect.[28],[29]

Given the contradictory findings of the existing studies, it seems necessary to conduct further studies with different statistical populations; if it is proved that lack of vitamin D has a major role in the incidence of type 2 diabetes, the compensation of this lack will constitute the main part of the treatment for diabetic patients. Thus, given the importance of the issue, variety in the research findings, difference in climatic conditions, the dietary regime of people in different areas, and the lack of conducting a similar study in Ilam, the present research was conducted to study HbA1C and vitamin D serum levels and determining the serum level of vitamin D in diabetic patients. Moreover, the patients' demographic variables [age, gender, smoking, place of residence, body mass index (BMI), diabetes duration, glycated hemoglobin, fasting glucose level, and vitamin D] were determined.


  Materials and Methods Top


The present study is a cross-sectional descriptive one conducted on the diabetic patients being referred to the internal clinic of a tertiary care hospital in Ilam. The patient's demographic and anthropometric information were recorded by using individual questionnaires. Sampling was conducted in the fasting state from 8 to 10 in the morning and before taking glucose-lowering drugs and the serum level of vitamin D was measured by using the enzyme-linked immunosorbent assay (ELISA) method and applying the kit. Given the prevalence of >70%, lack of vitamin D of 81 individuals was measured in diabetic patients with the sample size error rate of 0.1. For increasing the statistical power of the research, 102 patients were studied.

Sample size was selected randomly after implementing the inclusion and exclusion criteria. Inclusion criteria are as follows: diagnosed type 2 diabetes for >1 year; lack of drinking alcohol; lack of treatment with insulin; lack of menopause or pregnancy (for female participants); lack of taking intervention drugs or vitamin D (corticosteroids, anticonvulsants, and contraceptives); lack of history of angina, myocardial infraction, stroke, kidney or liver diseases, chronic inflammatory diseases, and thyroid diseases during the recent year; lack of treatment with thiazolidinedione drugs; and lack of smoking of all kinds. The exclusion criteria are suffering from diagnosed liver or kidney diseases, having a creatinine of >2 mg/dl, malabsorption, infertility, oligomenorrhea, pregnancy, breastfeeding, diagnosed malignancy, taking drugs affecting bone metabolism, drinking alcohol, inactivity for >1 week, taking calcium supplement in the last 2 weeks, taking vitamin D pills in the last 3 months, injection of vitamin D in the last 6 month, obesity (BMI >40 kg/m2), severe complications of diabetes in patients suffering from diabetes (nephropathy, retinopathy, and so on), and HbA1C >11%.

After recording the demographic and anthropometric characteristics, measuring the blood pressure, and after 12 h fasting, the qualified participants were referred to the laboratory, and 10 ml of blood was taken from them. The analysis of blood samples for measuring fasting blood sugar (FBS) was conducted by the Hitachi 917 auto analyzer. For measuring blood lipids profile Hitachi 917 machine was used by a photometric method. 25-hydroxyvitamin D serum level was measured by using the chemiluminescence method using LIAISON machine and it was then analyzed in the DIaSorin30 kit, and 30–100 ng/mL was determined as the natural amount. Moreover, 20 < vit D (OH) <25 ng/mL was determined as vitamin D deficiency, 25 < vit D <30 ng/mL was determined as inadequacy of vitamin D, and vit D >30 ng/mL was defined as adequacy of vitamin D.[30]

The data collected from the patients were inserted into the SPSS-20 and it was then analyzed by using relevant statistical tests. For describing the quantitative variables, mean and standard deviation were used. Moreover, for describing the qualitative variables, number and percentage were applied. The mean serum levels of HbA1C and vitamin D were compared for different variables using the Chi-square and analysis of variance (ANOVA). Glycated hemoglobin (HbA1C) was used as the gold standard of blood glucose control and a criterion for estimating the intensity of its complications.


  Findings Top


Frequency distribution of demographic variables and the means of quantitative variables are shown in [Table 1] and [Table 2].
Table 1: Frequency distribution of demographic variables in the patients studied

Click here to view
Table 2: The mean of quantitative variables in patients studied

Click here to view


The findings indicate a positive significant relationship between HbA1C and FBS [Table 3].
Table 3: Mean and standard deviation of HbA1C in patients studied according to different variables

Click here to view


The findings indicate that there is a significant relationship between the serum level of vitamin D with smoking and BMI [Table 4].
Table 4: Mean and standard deviation of the serum level of vitamin D in patients studied according to different variables

Click here to view


Pearson correlation coefficient test indicates that there is an inverse linear relationship between vitamin D with HbA1C, FBS, BMI, and disease duration. Moreover, Pearson correlation coefficient indicates that the relationship between HbA1C with FBS and disease duration was a linear direct one. The relationship between HbA1C and BMI was an inverse linear one and it was not significant [Table 5].
Table 5: The correlation coefficient between serum level of vitamin D and HbA1C with the indices studied

Click here to view



  Discussion and Conclusion Top


Based on the findings, the serum level of vitamin D was low in diabetic individuals, and in these patients, there was no significant relationship between serum level of vitamin D with diabetes duration and HbA1C.

The findings of this study indicated an inverse linear relationship between vitamin D with HbA1C (P < 0.37), FBS, (P < 0.64), BMI (P < 0.59), and disease duration (P < 0.1). There was also a direct linear relationship between HbA1C with FBS and disease duration (P < 0.000 and P < 0.000) and an inverse linear relationship between HbA1C and BMI (P < 0.41). Given the role of this vitamin in secretion and the effect of insulin, it seems useful to monitor the serum level of vitamin D diabetic patients and prescribe its supplements if necessary.

In the present study, 53.9% of the patients suffered from vitamin D deficiency, and this is more or less similar to the findings of the study conducted by Taheri et al.; vitamin D deficiency plays an important role in the pathogenesis of type 2 diabetes.

The findings of the study conducted by Hidayat et al. on elderly people suffering from type 2 diabetes in Indonesia revealed that the serum level of vitamin D is higher in men than that of women, and this difference is significant.[31]

The findings of the present study are similar to those of the study conducted by Bonakdaran and Varasteh; the serum level of vitamin D reduces as the BMI increases, and there is a significant statistical relationship between serum level of vitamin D and BMI.[32]

Pearson's correlation coefficient test indicated an inverse linear relationship between vitamin D with HbA1C (P < 0.37), FBS (0.64), BMI (P < 0.59), and disease duration (P < 0.1); the relationship was not statistically significant. Moreover, Pearson's correlation coefficient indicated that there was a direct linear relationship between HbA1C with FBS and disease duration, and the relationship was statistically significant (P < 0.000 and P < 0.000, respectively). However, the relationship between HbA1C and BMI was an inverse linear one, and the relationship was not significant (P < 0.41).

In the present study, there was an inverse relationship between BMI and HbA1C. However, it was not statistically significant. There was a direct and an indirect significant relationship between diabetes and HbA1C.

Pearson's correlation coefficient indicated no significant relationship between diabetes duration and vitamin D (P < 0.1 and r = 0.164). Moreover, this test indicated a linear and significant relationship between diabetes duration and HbA1C (P < 0.000 and r = 0.693). Longer duration of suffering from the disease will bring about an increase in HbA1C. This is not surprising, since given progressive process of diabetes, the patient will be at a more developed stage of the disease as the duration of diabetes increases, and it will be more difficult to control the disease. These findings confirm those of the studies conducted by Carter et al. (2000), Patti et al. (1995), and Simon et al. (1989).[33],[34],[35] However, statistically speaking, in the present study as well as that of Simon et al.[36] no significant relationship was found between HbA1C with factors such as age, gender, BMI, and smoking.

In the present study, no significant relationship was observed between serum level of vitamin D and HbA1C. However, in the study conducted by Danaei et al. (2014), a significant negative relationship has been reported between serum level of vitamin D and HbA1C.[37]

According to the present study as well as other studies conducted in this regard, since vitamin D necessary for human body is supplied through receiving foods, vitamin D supplements, and sunshine, and given the high prevalence of vitamin D deficiency in diabetic patients, it is recommended to adopt special measures to compensate the deficiency of this vitamin in diabetic patients.

Ethical considerations

The present study was conducted after acquiring the necessary permit from the University Ethics Committee as well as letter of consent from the patients participated.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Holick MF. Vitamin D deficiency. N Engl J Med 2007;357:266-81.  Back to cited text no. 1
    
2.
Esteghamati A, Gouya MM, Abbasi M, Delavari A, Alikhani S, Alaedini F, et al. Prevalence of diabetes and impaired fasting glucose in the adult population of Iran: National survey of risk factors for non-communicable diseases of Iran. Diabetes Care 2008;31:96-8.  Back to cited text no. 2
    
3.
Bringhurst FR, Demay MB, Krane SM, Kromenberg HM. Bone and mineral metabolism in health and disease. In: Kasper DL, Fauci AS, Longo DL, Braunwald E, Hauser SL, Jameson JL, editors. Harrison's principles of internal medicine. 16th ed. New York: McGraw Hill; 2005. p. 2238-48.  Back to cited text no. 3
    
4.
Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancer, and cardiovascular disease. Am J Clin Nutr. 2004;80:1678S-88S.  Back to cited text no. 4
    
5.
Marriott BM. Vitamin D supplementation: A word of caution. Ann Int Med 1997;127:231-3.  Back to cited text no. 5
    
6.
Norman AW. Sunlight, season, skin pigmentation, vitamin D, and 25-Hydroxyvitamin D: Integral components of the vitamin D endocrine system. Am J Clin Nutr 1998;67:1108-10.  Back to cited text no. 6
    
7.
Compston JE. Vitamin D deficiency: Time for action. BMJ 1998;317:1466-7.  Back to cited text no. 7
    
8.
Holick MF. Vitamin D deficiency. N Engl J Med 2007;357:266-81.  Back to cited text no. 8
    
9.
Mithal A, Wahl D, Bonjour JP, Burckhardt P, Dawson-Hughes B, Eisman J, et al. Global vitamin D status and determinants of hypovitaminosis D. Osteoporosis Int., 2009;20:1807-20.  Back to cited text no. 9
    
10.
Alvarez JA, Ashraf A. Role of vitamin d in insulin secretion and insulin sensitivity for glucose homeostasis. Int J Endocrinol 2010;2010:351-85.  Back to cited text no. 10
    
11.
Chiu KC, Chu A, Go VL, Saad MF. Hypovitaminosis D is associated with insulin resistance and beta cell dysfunction. Am J Clin Nutr 2004;79:820-5.  Back to cited text no. 11
    
12.
Liu E, Meigs JB, Pittas AG, McKeown NM, Economos CD, Booth SL, et al. Plasma 25-Hydroxyvitamin d is associated with markers of the insulin resistant phenotype in nondiabetic adults. J Nutr 2009;139:329-34.  Back to cited text no. 12
    
13.
Borissova AM, Tankova T, Kirilov G, Dakovska L, Kovacheva R. The effect of vitamin D3 on insulin secretion and peripheral insulin sensitivity in type 2 diabetic patients. Int J Clin Pract 2003;57:258-61.  Back to cited text no. 13
    
14.
Nimitphong H, Chanprasertyothin S, Jongjaroenprasert W, Ongphiphadhanakul B. The association between vitamin D status and circulating adiponectin independent of adiposity in subjects with abnormal glucose tolerance. Endocrine 2009;36:205-10.  Back to cited text no. 14
    
15.
Scragg R, Sowers M, Bell C. Serum 25- hydroxyvitamin D, diabetes, and ethnicity in the third national health and nutrition examination survey. Diabetes Care 2004;27:2813-8.  Back to cited text no. 15
    
16.
Sung CC, Liao MT, Lu KC, Wu CC. Role of vitamin D in insulin resistance. J Biomed Biotechnol 2012;2012:634195.  Back to cited text no. 16
    
17.
Chiu KC, Chu A, Go VL, Saad MF. Hypovitaminosis D is associated with insulin resistance and beta cell dysfunction. Am J Clin Nutr 2004;79:820-5.  Back to cited text no. 17
    
18.
Pittas AG, Lau J, Hu FB, Dawson-Hughes B. The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. J Clin Endocrinol Metab 2007;92:2017-29.  Back to cited text no. 18
    
19.
Van Etten E, Mathieu C. Immunoregulation by 1, 25-dihydroxyvitamin D3: basic concepts. J Steroid Biochem Mol Biol 2005;97:93-101.  Back to cited text no. 19
    
20.
Maghbooli Z, Hossein-Nezhad A, Karimi F, Shafaei AR, Larijani B. Correlation between vitamin D3 deficiency and insulin resistance in pregnancy. Diabetes Metab Res Rev 2008;24:27-32.  Back to cited text no. 20
    
21.
Poole KE, Loveridge N, Barker PJ, Halsall DJ, Rose C, Reeve J, Warburton EA. Reduced vitamin D in acute stroke. Stroke 2006;37:243-5.  Back to cited text no. 21
    
22.
Poel YH, Hummel P, Lips P, Stam F, van der Ploeg T, Simsek S. Vitamin D and gestational diabetes: A systematic review and meta-analysis. Eur J Intern Med 2012;23:465-9.  Back to cited text no. 22
    
23.
Giovannucci E. Vitamin D and cancer incidence in the Harvard cohorts. Ann Epidemiol 2009;19:84-8.  Back to cited text no. 23
    
24.
Liu S, Song Y, Ford ES, Manson JE, Buring JE, Ridker PM. Dietary calcium, vitamin D, and the prevalence of metabolic syndrome in middle-aged and older U.S. women. Diabetes Care 2005;28:2926-32.  Back to cited text no. 24
    
25.
Knekt P, Laaksonen M, Mattila C, Harkanen T, Marniemi J, Heliovaara M, et al. Serum vitamin D and subsequent occurrence of type 2 diabetes. Epidemiology 2008;19:666-71.  Back to cited text no. 25
    
26.
Scragg R, Holdaway I, Singh V, Metcalf P, Baker J, Dryson E. Serum 25-hydroxyvitamin D3 levels decreased in impaired glucose tolerance and diabetes mellitus. Diab Res Clin Pract 1995;27:181-8.  Back to cited text no. 26
    
27.
Shi H, Norman AW, Okamura WH, Sen A, Zemel MB. 1, 25-Dihydroxyvitamin D3 modulates human adipocyte metabolism via nongenomic action. FASEB J 2001;15:2751-3.  Back to cited text no. 27
    
28.
Ford ES, Ajani UA, McGuire LC, Liu S. Concentrations of serum vitamin D and the metabolic syndrome among US adults. Diabetes Care 2005;28:1228-30.  Back to cited text no. 28
    
29.
Parikh SJ, Edelman M, Uwaifo GI, Freedman RJ, Semega-Janneh M, Reynolds J, et al. The relationship between obesity and serum 1, 25- dihydroxy vitamin D concentrations in healthy adults. J Clin Endocrinol Metab 2004;89:1196-9.  Back to cited text no. 29
    
30.
Haffner SM, Lehto S, Ronnemaa T. Mortality from coronary heart disease in subjects with type 2 diabetes and in nondiabetic subjects with and without prior myocardial infarction. N Engl J Med 1998;339:229-34.  Back to cited text no. 30
    
31.
Forouhi NG, Luan J, Cooper A, Boucher BJ, Wareham NJ. Baseline serum 25-hydroxy vitamin d is predictiveof future glycemic status and insulin resistance: The medical research council ely prospective study 1990-2000. Diabetes 2008;57:2619-25.  Back to cited text no. 31
    
32.
Hidayat R, Setiati S, Pradana S. The association between vitamin D deficiency and type 2 diabetes mellitus in elderry patients. Acta Med Indones 2010;42:123-9.  Back to cited text no. 32
    
33.
Bonakdaran S, Varasteh AR. Correlation between serum 25 hydroxy vitamin D3 and laboratory risk markers of cardiaovascular disease in type 2 diabetic patients. Saudi Med J 2009;30:509-14.  Back to cited text no. 33
    
34.
Carter JS, Gilliland SS, Perez GE, Skipper B, Gilliland FD. Public health and clinical implications of high hemoglobin A1C Levels and weight in younger adult. Native American people with diabetes. Arch Intern Med 2000;160:3471-6.  Back to cited text no. 34
    
35.
Patti L, Di Marino L, Maffettone A. Very low density subfraction abnormalities in iddm patients: Any effect of blood glucose control? Diabetologia 1995;38:1419-24.  Back to cited text no. 35
    
36.
Simon D, Senan C, Garnier P, Saint. Paul M, Papoz L. Epidemiological features of glycated haemoglobin A1C- distribution in a healthy population. The Telecom Study. Diabetologia 1989;32:864-9.  Back to cited text no. 36
    
37.
Danaei N, Tamadon M, Monsan M. Evaluation of diabetes control and some related factors in patients of diabetes clinic of semnan fatemieh hospital. Komesh 2004;6:31-6.  Back to cited text no. 37
    



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

Top
   
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
   Abstract
  Introduction
   Materials and Me...
  Findings
   Discussion and C...
   References
   Article Tables

 Article Access Statistics
    Viewed73    
    Printed1    
    Emailed0    
    PDF Downloaded22    
    Comments [Add]    

Recommend this journal