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Understanding Diabetes

What is Diabetes

A lifelong disease that causes high blood sugar-level, as it affects the way the body converts food into energy. (*1,*2)

ACare for Diabetes Management

Understanding The Food-To-Energy Conversion Process

Normal Person Diabetic Person
STEP 1 Food eaten by you is turned into sugar (glucose) Food eaten by you is turned into sugar (glucose)
STEP 2 Pancreas (an organ near the stomach) makes a hormone called insulin Pancreas (an organ near the stomach) does not make sufficient insulin or body is unable to use it properly
STEP 3 Insulin helps sugar enter into cells of your body Sugar accumulates in your blood
STEP 4 Sugar is converted into energy Leads to diabetes

Why Do You Need Glucose?

Glucose or Sugar3

  • Main source of energy for the cells in your body
  • Sugar is absorbed into bloodstream, and enters cells with the help of insulin
  • Your liver stores glucose, so that it can make it available when your blood sugar levels are low 

Why Do You Need Glucose?

Why Do You Need Insulin?

Insulin3

  • A hormone produced by pancreas, which is an organ near the stomach 
  • Serves as a key to help glucose or sugar enter the cells in your body 
  • Lowers level of sugar in your bloodstream
  • Production reduces with decreasing level of blood sugar 

Why Do You Need Insulin?

Articles on Managing Diabetes

Read articles on how to manage diabetes while eating out, fasting and exercising

Eating Out with Diabetes

Things to remember when you go out to eat.

Fasting with Diabetes

It’s important to follow rules while fasting with diabetes.

Exercising with Diabetes

One must exercise regularly to manage diabetes well.

Safe fasting with Diabetes

SAFE FASTING WITH DIABETES
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References

1. Centers for Disease Control and Prevention. Diabetes. Available from: https://www.cdc.gov/media/presskits/aahd/diabetes.pdf.  As accessed on: 19/6/2018.
2. Diabetes UK. Diabetes: The basics. Available from: https://www.diabetes.org.uk/diabetes-the-basics. As accessed on: 19/6/2018.
3. Mayoclinic. Type 1 diabetes. Available from: https://www.mayoclinic.org/diseases-conditions/type-1-diabetes/symptoms-causes/syc-20353011. Last revised: 7/8/2017. As accessed on: 19/6/2018.

4. International Diabetes Federation. IDF Diabetes Atlas - 8th Edition. Available from: https://www.diabetesatlas.org/across-the-globe.html. As accessed on: 27/6/2018.
5. Joslin Diabetes Center. Ten Things You Might Not Know About Diabetes. Available from: https://www.joslin.org/info/10_Things_You_Might_Not_Know_About_Diabetes.html. As accessed on: 19/6/2018.
6. World Health Organization. 10 facts on diabetes (2016). Available from: https://www.who.int/features/factfiles/diabetes/en/. As accessed on: 19/6/2018. 
7. Diabetes in Canada. Types of diabetes. Available from: https://www.diabetes.ca/about-diabetes/types-of-diabetes. As accessed on: 19/6/2018.
8. National Health Service. Gestational diabetes. Available from: https://www.nhs.uk/conditions/gestational-diabetes/. Last reviewed: 5/8/2016. As accessed on: 19/6/2018.

Introduction

Thyroid disorders, particularly hypothyroidism, are common among Indian patients.1 Unnikrishnan et al. have recently reported that hypothyroidism is prevalent in about 10.95% of adult urban population in India. Further, the prevalence is higher among females and elderly individuals. It is also estimated that subclinical hypothyroidism is prevalent in about 8% population.2 A cross sectional study by Marwaha et al reported 25% prevalence of Subclinical hypothyroidism in Dyslipidemia patients.3 Thyroid disorders have significant impact on lipids as well as other cardiovascular risk factors. Several studies have reported that overt hypothyroidism as well as subclinical hypothyroidism may cause significant lipid abnormalities.4-7 Hence, effective screening and management for thyroid dysfunction is critical in all patients with dyslipidemia.4

Effects of thyroid hormones on lipid metabolism8

Thyroid hormones regulate a wide range of metabolic parameters and have significant effect on lipoprotein metabolism thereby influencing the overall cardiovascular disease (CVD) risk. Following are the effects of thyroid hormones on lipid metabolism.

Thyroid hormones:

  • Induce the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the first step in cholesterol biosynthesis.
  • Influence the metabolism of HDL by increasing cholesteryl ester transfer protein (CETP) activity.
  • Stimulate the lipoprotein lipase (LPL)
    • Which catabolizes the triglycerides (TG)-rich lipoproteins and the hepatic lipase (HL)
    • Hydrolyzes high density lipoproteins (HDL)2 to HDL3 and converts intermediate-density lipoproteins (IDL) to low density lipoproteins (LDL) and in turn LDL to small dense LDL (sdLDL)
  • Triiodothyronine (T3) directly binds to specific thyroid hormone responsive elements (TREs) and controls the LDL receptor gene activation thereby upregulating LDL receptors.
  • T3 also controls the sterol regulatory element-binding protein-2 (SREBP-2), and in turn regulates LDL receptor’s gene expression. Moreover, T3 protects LDL from oxidation.
  • T3 upregulates apolipoprotein AV (ApoAV) and decreases levels of TGs. This increases the clearance of lipoprotein core remnants.

Association between lipid profiles and thyroid function

Analysis of patients with subclinical hypothyroidism

Asranna et al. found that patients with subclinical hypothyroidism exhibited higher mean total cholesterol and mean LDL cholesterol levels as compared to controls (Figure 1). They concluded that dyslipidemia is more common among patients with subclinical hypothyroidism than that among controls.6

Analysis of patients with subclinical and overt hypothyroidism

Sharma et al. evaluated the lipid profiles and thyroid function in patients with subclinical hypothyroidism (n=30) and overt hypothyroidism (n=30) as compared to that in healthy controls (n=30). The findings of the study are given in Table 1. TSH showed statistically significant correlation with total cholesterol, triglyceride, LDL cholesterol and HDL cholesterol in patients with subclinical and overt hypothyroidism.7

Role of thyroxine treatment

Effect on lipid metabolism

Asranna et al. observed a significant reduction in mean total cholesterol, LDL cholesterol, very low-density lipoprotein cholesterol, and triglyceride levels with 3 month of thyroxine treatment.6

Effect on cardiovascular events

Razvi et al. found that thyroxine treatment was associated with fewer incidence of ischemic heart disease in younger patients with subclinical hypothyroidism (4.2 vs. 6.5%; multivariate-adjusted hazard ratio: 0.61; 95% confidence interval: 0.39–0.95; p=0.02; (Figure 2).9

ITS Guideline Recommendations on Screening and Management of Dyslipidemia

  • Universal screening is indicated for thyroid disorders in all patients with dyslipidemia.
  •  The preferred test for screening is the measurement of TSH. If the TSH is elevated, measurement of serum T4 is required to differentiate between overt and subclinical thyroid disease
  • All patients with hyperlipidemia and overt hypothyroidism should be treated with Thyroxine
  • therapy first. A period of 4-6 weeks of replacement therapy is usually needed to correct the dyslipidemia
  • If adequate response is not seen with Thyroxine therapy alone after 4 to 6 weeks of therapy administer lipid-lowering medications
  • As Thyroxine treatment may exacerbate myocardial ischaemia in patients with underlying CAD, start treatment at lower doses (25 mcg/day) and titrate
  • gradually (12.5 to 25.0 mcg increments) at intervals of 4–6 weeks with monitoring of TSH levels and ECG
  • Use of statin in hypothyroidism with dyslipidemia should be customized
  • No known underlying CAD or risk of CAD-Wait till patient becomes euthyroid and repeat lipid profile and proceed according to NCEP guidelines
  • In presence of underlying CAD or acute coronary syndrome start statin along with Thyroxine replacement
  • Use of statin or fibrates alone or in combination in patients with dyslipidemia and uncontrolled hypothyroidism carries a higher risk of myopathy
  • Risk of myopathy may also be associated with the co - administration of statins with Thyroxine

References

  1. Indian Thyroid Society (ITS).Guidelines for the Management of Dyslipidemia and Thyroid Dysfunction A Clinical Practice Guideline. Available from: http://apiindia.org/pdf/pdf_index/dyslipidemia_and_thyroid_dysfunction_guidelines.pdf Accessed on March 9, 2016.
  2. Unnikrishnan AG, Kalra S, Sahay RK, et al. Prevalence of hypothyroidism in adults: An epidemiological study in eight cities of India. Indian J Endocrinol Metab. 2013;17(4):647-52.
  3. Marwaha RK, Tandon N, Garg MK, et al. Dyslipidemia in subclinical hypothyroidism in an Indian population. Clin Biochem. 2011 Oct;44(14-15):1214-7.
  4. Brenta G, Fretes O. Dyslipidemias and hypothyroidism. Pediatr Endocrinol Rev. 2014;11(4):390-9.
  5. Dixit AK, Dey R, Suresh A, et al. Lipid Profile of Patients with Thyroid Dysfunction in Ayurveda Hospital.Int J Biomed Res. 2014;05(04):241-3.
  6. Asranna A, Taneja RS, Kulshreshta B. Dyslipidemia in subclinical hypothyroidism and the effect of thyroxine on lipid profile. Indian J Endocrinol Metab. 2012;16(Suppl 2):S347-9.
  7. Sharma P, Patgiri D, Goya S. Hypothyroidism causing dyslipidemia in both subclinical & overt hypothyroidism. Indian Journal of Basic & Applied Medical Research. 2013;2(7):779-88.
  8. Rizos CVElisaf MSLiberopoulos EN. Effects of thyroid dysfunction on lipid profile. Open Cardiovasc Med J. 2011;5:76-84.
  9. Razvi S, Weaver JU, Butler TJ, et al. Levothyroxine treatment of subclinical hypothyroidism, fatal and nonfatal cardiovascular events, and mortality. Arch Intern Med. 2012;172(10):811-7.
  10. Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014;24(12):1670-751.