International Journal of Clinical Biochemistry and Research

Print ISSN: 2394-6369

Online ISSN: 2394-6377

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International Journal of Clinical Biochemistry and Research (IJCBR) open access, peer-reviewed quarterly journal publishing since 2014 and is published under auspices of the  Innovative Education and Scientific Research Foundation (IESRF), aim to uplift researchers, scholars, academicians, and professionals in all academic and scientific disciplines. IESRF is dedicated to the transfer of technology and research by publishing more...


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Anveetha and Vamsi Krishna: Study of thyroid profile in relation to glycemic control in type 2 diabetes mellitus patients


Introduction

Diabetes mellitus (DM), a leading cause of death around the world, is one of the most difficult health issues of the twenty-first century.1, 2, 3 It's a category of metabolic diseases marked by chronic hyperglycemia caused by problems with insulin secretion, insulin action, or both. Diabetes is caused by a variety of pathogenic mechanisms, ranging from autoimmune destruction of pancreatic cells, resulting in insulin deficiency, to defects that result in insulin resistance.4, 5 The overwhelming majority of diabetic cases can be divided into two groups based on their etiopathogenetic causes. One type of diabetes is Type 1, which is caused by a complete lack of insulin secretion. Type 2 diabetes is a more common form of diabetes mellitus that is caused by a combination of insulin action and secretion problems.4, 5 Diabetes prevalence was projected to be 2.8 percent in 2000 and 4.4 percent in 2030 by the World Health Organization (WHO). The global diabetes population is projected to grow from 171 million in 2000 to 366 million by 2030.[6.7] Sedentary behavior, dietary changes, race, hypertension, and obesity are all thought to play a role in this epidemic. The two most common endocrinopathies seen in clinical practice are thyroid disease and diabetes mellitus. Diabetes and thyroid disorders have been shown to have reciprocal effects, and a connection between the two has been discovered in the literature.6, 7 In 1979, a study was published that showed a connection between diabetes and thyroid dysfunction.8 Since then, a variety of studies have reported that between 2.2 and 17 percent of diabetic patients have thyroid dysfunctions.9, 10 However, fewer studies have found a much higher incidence of thyroid dysfunction in diabetics, at 31 percent and 46.5 percent, respectively.11, 12 Thyroid disorders are more common in diabetic patients than in the general population.13

Upon stimulation by thyroid-stimulating hormone (TSH), the thyroid gland responds by producing and releasing the 2 thyroid hormones: Triiodothyronine (T3) and Thyroxine (T4).14 Hyperthyroidism and hypothyroidism are the two most common thyroid gland pathological disorders.15, 16 Hypothyroidism is the most common thyroid condition in adults, and it occurs when the thyroid gland does not produce enough thyroid hormones. Hyperthyroidism is a disorder in which the thyroid gland is overactive and releases too many thyroid hormones.4

Since insulin and thyroid hormones are so intertwined in cellular metabolism, having too much or too little of one causes the other to malfunction. Insulin's physiological and biochemical interactions, as well as the effects of insulin and iodothyronines on carbohydrate, protein, and lipid metabolism, have been studied. According to these documents, iodothyronines are insulin antagonists, with high levels being diabetogenic and the absence of the hormone inhibiting the development of diabetes.17

Thyroid dysfunction can make diabetes more difficult to manage. Hyperthyroidism raises the rate of gastrointestinal glucose absorption, as well as insulin resistance and insulin degradation, and is linked to worsening glycemic control in diabetics, whereas hypothyroidism increases hypoglycemia vulnerability, complicating diabetes management.18 Thyroid hormone disorders are often linked to diabetes, and thyroid dysfunction that goes undiagnosed may harm diabetes and its complications.7 This study aimed to assess the thyroid profile in type 2 diabetic patients.

Materials and Methods

The total numbers of subjects studied were 120, comprising 60 patients of type 2 diabetic mellitus (Cases group) and 60 normal healthy individuals (Control group). 60 cases include patients with and without good glycemic control. Both cases and controls gave their informed consent.

The cases were chosen using a straightforward random sampling procedure. Patients with coronary artery disease, cerebrovascular accident, hypertension were included in exclusion criteria. The duration of diabetes, treatment (hypoglycemic agent or insulin or diet control alone) was noted. Cases and controls have given fasting blood samples. Serum T3, T4, and TSH were estimated by using CLIA (Chemiluminescence Immunoassay) method and Fasting blood glucose by Glucose Oxidase-Peroxidase method HbA1c was estimated by Ion-Exchange Resin method.

Inclusion criteria

  1. Cases: 60 type-2 diabetics of age 45 - 60 yrs of both genders who were on treatment, with no known complications and no history of previous thyroid disease were included. 60 cases include patients with and without good diabetic control

  2. Controls: 60 age and sex-matched normal healthy individuals without any history of diabetes and known systemic disorders were included.

Exclusion criteria

Individuals with a previous history of thyroid disease and on drugs that affect thyroid function, pregnancy, patients with diabetic complications (coronary artery disease, cerebrovascular accident, hypertension).

Criteria used in the study for the diagnosis of type 2 DM (According to American Diabetic Association) are 1) FBS (Fasting Blood Sugar) ≥ 126 mg/dl (7.0 mmol/L) or 2) Symptoms of diabetes plus RBS (Random Blood Sugar) ≥ 200 mg/dl (11.1 mmol/L).

Statistical analysis

The results obtained and expressed in mean ± SD. Student t-test was used to compare the two classes, and SPSS statistical package version 15.0 was used to evaluate each parameter statistically. A p-value of 0.05 was considered statistically important.

Results

The participants in this study ranged in age from 45 to 60 years old. The mean age of diabetics was 50.96 ± 4.86 years and the mean age of controls was 51.24 ± 5.14 years. This case-control research included 60 type 2 diabetic patients of both genders who were on medication and had no reported symptoms or prior thyroid disease.

Table 1

Sex and age wise distribution of cases and controls

Males

Females

Mean ages

Cases

36

24

50.96 ± 4.86

Controls

32

28

51.24 ± 5.14

Table 2

Test parameters in cases and controls

Parameter

Cases (Mean ± SD)

Controls (Mean ± SD)

‘P’ value

Inference

FBS (mg/dl)

198.12 ± 54.46

96.28 ± 12.24

< 0.001

Significant

HbA1c (%)

8.52 ± 2.36

5.12 ± 0.16

< 0.001

Significant

T3 (ng/ml)

1.08 ± 0.46

1.49 ± 0.38

< 0.05

Significant

T4 (µg/ml)

6.52 ± 3.14

8.24 ± 2.12

< 0.05

Significant

TSH (µIU/ml)

8.52 ± 3.42

2.36 ± 1.68

< 0.05

Significant

Table 3

Thyroid parameters in cases with good glycemic control and cases without good glycemic control

Parameter

Cases With Good Diabetic Control (HbA1c ≤ 7.0%)

Cases Without Good Diabetic Control (HbA1c > 7.0%)

‘P’ value

Inference

T3 (ng/ml)

1.24 ± 0.32

0.92 ± 0.28

< 0.01

Significant

T4 (µg/ml)

7.74 ± 3.14

5.30 ± 1.84

< 0.01

Significant

TSH (µIU/ml)

7.62 ± 1.92

9.42 ± 2.96

< 0.01

Significant

Figure 1

Showing Mean HbA1c levels in Cases

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/b9c26aac-64a1-4a5b-943c-b79e68f01cbb/image/ee895c6a-33ed-43b2-8bb0-4fe44e6252c3-uimage.png

When compared to controls, serum T3 and T4 levels were significantly lower, whereas serum TSH levels were significantly higher in cases. Within the cases, the abnormality in thyroid hormones was more significant in cases without good glycemic control (HbA1c > 7.0%).

Discussion

Diabetes, an endocrine metabolic disorder with a wide range of symptoms, is a leading cause of morbidity and mortality around the world. It has a global distribution and is becoming more common every day, posing a serious threat to public health around the world.19 India will continue to have the highest number of diabetic subjects as a result of rapid urbanization and economic growth.20 Diabetes is commonly associated with altered thyroid function. After diabetes, thyroid disorders are the most prevalent endocrine disorders in the general population. As a result, it is normal for a person to suffer from both thyroid disease and diabetes.1 The study aims to look at the levels of serum T3, T4, and TSH, as well as fasting blood sugar in type 2 diabetics. The present study includes 120 subjects of which 60 were known type 2 diabetic patients (cases) and 60 were normal healthy controls. When compared to controls, diabetics had significantly lower serum T3, T4 levels, while diabetics had significantly higher serum TSH levels. This is by the studies of Vikram BV et al.,21 Gurjeet S et al., 1 and Shekhar CY et al.15

The mean fasting blood sugar level in controls was 96.28 ± 12.24 mg/dl and the mean fasting blood sugar level in cases was 198.12 ± 54.46 mg/dl. The mean HbA1c level in controls was 5.12 ± 0.16% and the means HbA1c levels in cases was 8.52 ± 2.36 %. When comparing cases to controls, fasting blood sugar and HbA1c levels were significantly higher in cases (p-value 0.001). This is consistent with the findings of Priti S et al.,22 Reeta T et al.23 and Samatha P et al.24

The mean serum T3 & T4 levels in controls were 1.49 ± 0.38 ng/ml & 8.24 ± 2.12 µg/ml and mean serum T3 & T4 levels in cases were 1.08 ng/ml ± 0.46 & 6.52 ± 3.14 µg/ml. There was a significant decrease in serum T3 & T4 levels in cases when compared to controls (p-value < 0.05). The mean serum TSH levels in controls were 2.36 ± 1.68 µIU/ml and mean serum TSH levels in cases was 8.52 ± 3.42 µIU/ml. When compared to controls, there was a significant increase in serum TSH levels in cases (p-value < 0.05). Out of 60 diabetic subjects investigated in the present study, 32% of diabetic patients had shown thyroid dysfunction with hypothyroidism. These findings support studies by Vibha U et al.6 and Pasupathi P et al.25 that indicate a high incidence of abnormal thyroid hormone levels in diabetics.

The mean serum T3 & T4 levels in cases with good glycemic control were 1.24 ± 0.32 ng/ml & 7.74 ± 3.14 µg/ml and mean serum T3 & T4 levels in cases without good glycemic control were 0.92 ± 0.28 & 5.30 ± 1.84 µg/ml. When compared to cases with good glycemic control, serum T3 and T4 levels were significantly lower in cases without good glycemic control (p-value < 0.001). The mean serum TSH levels in cases with good glycemic control was 7.62 ± 1.92 µIU/ml and mean serum TSH levels in cases without good glycemic control was 9.42 ± 2.96 µIU/ml. When compared to cases with good glycemic control, there was a large rise in serum TSH levels in cases without good glycemic control (p- value < 0.001). When comparing cases to controls, thyroid parameters show a noticeable difference. In cases where glycemic regulation was weak, the abnormality was more pronounced. Diabetes is influenced by endocrine and non-endocrine organs other than the pancreas. Some endocrine abnormalities, such as altered thyroid hormone levels, are occasionally discovered in diabetic patients. The presence of both high and low thyroid hormone levels in diabetics in this study may be due to a change in thyroid releasing hormone (TRH) synthesis and release, which could be influenced by the diabetics' glycemic status. Insulin, which is believed to modulate the levels of TRH and TSH, influences glycemic status.9, 26

In diabetes, there are alterations in the hypothalamic–pituitary–thyroid axis. The hypothalamic and plasma TRH, pituitary and plasma TSH, and TSH secretion rate are among the most significant changes. Despite normal peripheral TSH metabolism, the response of TSH to TRH is also decreased. Thyroid gland output of T3 and T4, as well as iodide uptake, are reduced. Both the thyroid and pituitary glands undergo significant structural changes, which are followed by significant changes in their secretory activities. Furthermore, the deiodination of T4 to T3 is reduced.25 Thyroid hormone-binding inhibitor (THBI), an inhibitor of the extrathyroidal conversion enzyme (5'-deiodinase) of T4 to T3, and hypothalamic–pituitary–thyroid axis dysfunction were attributed by Suzuki et al to abnormal thyroid hormone levels observed in diabetes. These conditions can arise in diabetics, and they will be exacerbated in diabetics who are poorly regulated. In these diabetics, stress, which is linked to diabetes, can trigger changes in the hypothalamus-anterior pituitary axis.27

Conclusion

When type 2 diabetics were compared to controls, serum T3 and T4 levels were lower, while serum TSH levels were higher. In cases where glycemic regulation was poor, abnormalities in serum T3, T4, and TSH levels were more noticeable. Thyroid hormone levels that are altered are more common in type 2 diabetics. Thyroid hormone abnormalities were more prevalent in diabetics with impaired glycemic regulation. Thyroid hormone levels that are altered in diabetics can be a primary cause of poor control in some treated diabetics if they are not understood. Thyroid hormones must be tested in diabetics to diagnose and treat thyroid disease early. Diabetics should have their thyroid function checked regularly to help avoid complications. This contributes to improved treatment by lowering morbidity and improving quality of life.

Source of Funding

None.

Conflict of Interest

None.

References

1 

S Gurjeet G Vikas SA Kumar S Neeraj Evaluation of thyroid dysfunction among type 2 diabetic Punjabi populationAdv Biores20112239

2 

S Faghilimnai M Hashemipour B Kelishadi Lipid profile of children with type 1 diabetes compared to controlsARYA .J2006213638

3 

V Shonima MI Uma Risk factor analysis and prevalence of microalbuminuria among type 2 Diabetes Mellitus Subjects: The need for screening and monitoring MicroalbuminAsian J Exp Biol Sci2010136529

4 

B Sachin M Mahesh S Sachin G Vaishali Evaluation of Thyroid Hormones in Patients with Type II Diabetes MellitusJ Med Educ Res201332339

5 

Diagnosis and classification of diabetes mellitusDiabetes care201033562569

6 

V Uppal C Vij GK Bedi A Vij BD Banerjee Thyroid Disorders in Patients of Type 2 Diabetes MellitusIndian J Clin Biochem20132843364110.1007/s12291-012-0293-9

7 

Mirella Hage MS Zantout ST Azar Thyroid Disorders and Diabetes MellitusJ Thyroid Res201120111710.4061/2011/439463

8 

J Feely TE Isles Screening for thyroid dysfunction in diabetics.BMJ197916179167810.1136/bmj.1.6179.1678

9 

P Perros RJ McCrimmon G Shaw BM Frier Frequency of Thyroid Dysfunction in Diabetic Patients: Value of Annual ScreeningDiabet Med1995127622710.1111/j.1464-5491.1995.tb00553.x

10 

MJ Smithson Screening for thyroid dysfunction in a community population of diabetic patientsDiabet Med19981521485010.1002/(sici)1096-9136(199802)15:2<148::aid-dia540>3.0.co;2-h

11 

CEJ Udiong AE Udoh ME Etukudoh Evaluation of thyroid function in diabetes mellitus in Calabar, NigeriaIndian J Clin Biochem200722274810.1007/bf02913318

12 

MF Celani ME Bonati N Stucci Prevalence of abnormal thyrotropin concentrations measured by a sensitive assay in patients with Type 2 dmDiabet Res19942711525

13 

P Wu Thyroid disease and diabetesClin Diabetes20001813841

14 

S Rajender JH Alaa A Ashok Thyroid Hormones in Male Reproduction and FertilityOpen Reprod Sci J2011398104

15 

SC Yadav A Saldhana B Majumdar Status of thyroid profile in Type-2 diabetes mellitisJ Nobel Med Coll20121272610.3126/jonmc.v1i2.7302

16 

US Barzel Thyroid decrease after the sixth decadeCurr Ther Endo Metab199761347

17 

DK Granner RK Murray DK Granner PA Mayes VW Rodwell Thyroid hormonesBiochemistry20005338

18 

JL Johnson Diabetes Control in Thyroid DiseaseDiabetes Spectr20061931485310.2337/diaspect.19.3.148

19 

M Shihabudheen K Prasanth NV Dilip C Danisha P Zainul A Seena Assessment of risk factors among type 2 diabetic populations in South Malabar region of KeralaArch Appl Sci Res20102431323

20 

R Dhananjayan T Malati G Brindha KV Kumar Association of family history of type 2 diabetes mellitus with markers of endothelial dysfunction in South Indian populationIndian J Biochem Biophys201350938

21 

BV Vikram AK Shubhangi KT Krunal NG Anu K Meenakshi RA Rajani Thyroid Dysfunction In Patients With Type 2 Diabetes Mellitus At Tertiary Care Centre Natl J Med Res2013337780

22 

S Priti K Salman MR Kumar Evolution of thyroid dysfunction among type-2 diabetic mid and far western Nepalese populationJ Coastal Life Med20142119036

23 

T Reeta SM Bindu M Smita Evaluation of Thyroid Dysfunction in Type II DM: A Case Control StudyInt J Curr Med Appl Sci2013111620

24 

P Samatha M Venkateswarlu S Prabodh V Lipid Profile Levels in Type 2 Diabetes Mellitus from the Tribal Population of Adilabad in Andhra Pradesh, IndiaJ Clin Diagn Res2012645902

25 

P Pasupathi G Bakthavathsalam G Saravanan R Sundaramoorthi Screening for Thyroid Dysfunction in the Diabetic/Non-Diabetic PopulationThyroid Sci20083816

26 

CE Reusch K Tomsa Serum fructosamine concentration in cats with overt hyperthyroidismJ Am Vet Med Asso1999215129730

27 

Y Suzuk M Nanno R Gemma I Tanaka T Taminato T Yoshimi The Mechanism of Thyroid Hormone Abnormalities in Patients with Diabetes MellitusNippon Niabunpi Gakki Zasshi19947044657010.1507/endocrine1927.70.4_465



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Penugonda Anveetha, Chittimoju Vamsi Krishna


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