HbA1c-deceptive Levels in Subclinical Hypothyroidism?

  • D Ponnudhali Professor & HOD, Dept. of Biochemistry, Vinayaka Mission’s Kirupananda Variyar Medical College & Hospital, Salem.
  • S Preetha Vinayaka Mission’s Kirupananda Variyar Medical College & Hospital, Salem.
  • Nirmal Sujitha IJ Vinayaka Mission’s Kirupananda Variyar Medical College & Hospital, Salem.
Keywords: Subclinical Hypothyroidism, TSH, HbA1c, Non-diabetic


Background: Subclinical hypothyroidism (SH) has been known to be related to type 2 diabetes mellitus and prediabetes. The association of SH with insulin resistance and altered glycemic status has been reported in past studies. We have aimed to look for the relationship of subclinical hypothyroidism with HbA1c levels, among non-diabetic individuals.
Aim & Objectives: To compare the HbA1c levels among non-diabetic participants with subclinical hypothyroidism (SH), and healthy controls having normal thyroid function
Materials & Methods: It is an analytical cross-sectional study carried out among 33 non-diabetic individuals with subclinical hypothyroidism and 36 euthyroid people. Mean serum HbA1c, TSH and other thyroid parameters were compared among the 2 groups, using independent “t” test. Spearman’s correlations were done, along with the odds ratio for the risk of association of HbA1c levels with subclinical hypothyroidism.
Results: Serum HbA1c levels were significantly enhanced in the SH group (4.91 ± 0.88 %) compared to healthy controls (4.39 ± 0.89 %, p = 0.018). A significant positive correlation was found to exist between TSH and HbA1c levels (p = 0.002).
Conclusion: Serum HbA1c levels were increased in non-diabetic individuals with subclinical hypothyroidism. This should be taken into consideration while analysing the HbA1c values in the diagnosis of diabetes/ prediabetes.

How to cite this article:
Ponnudhali D, Preetha S, Nirmal Sujitha IJ. HbA1cdeceptive Levels in Subclinical Hypothyroidism?
Chettinad Health City Med J. 2023;12(2):71-76.

DOI: https://doi.org/10.24321/2278.2044.202330


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