Risk Factors of Thyroid Dysfunction in Patients With Type 2 Diabetes Mellitus.

Stanley U. Ogbonna,Ignatius U. Ezeani

doi:10.3389/fendo.2019.00440

Abstract

Background: Thyroid dysfunction has been widely reported among persons with diabetes (DM) in other parts of the World. In Nigeria, few studies have been reported. This study focused on risk factors for thyroid dysfunction in type 2 diabetes mellitus (T2DM) patients and will therefore add to the Nigerian literature, more so, as it is the first in South-East Nigeria.Objective: To determine the risk factors of thyroid dysfunction in patients with Type 2 DM.Methodology: Three hundred and fifty-four T2DM patients and 118 non-diabetic persons (controls) were recruited for the study. A pretested questionnaire was filled for each subject after due explanations. The subjects were subsequently examined and the findings, including anthropometric values and clinical parameters were documented. Their blood samples were tested for HbA1c, fT3, fT4, and TSH. Information retrieved from patients medical records included: age at diagnosis of DM, duration of DM, complications of DM. The Student's t-test, chi square test and regression analysis were used in the analysis of the data obtained. P < 0.05 was taken to be statistically significant.Results: About 56.5% of the T2DM patients who participated in this study were females and 62.7% of the controls were females. The T2DM patients had significantly higher BMI than controls (27.6 ± 5.0 kg/m2 vs. 26.2 ± 3.8 kg/m2, p = 0.002). Mean HbA1c was significantly higher in T2DM patients than in the controls (7.8 ± 2.0% vs. 5.8 ± 1.2%, p = 0.001). Female gender (OR = 3.8, p = 0.002), central obesity (OR = 2.5, 95%CI = 1.5–5.2, p = 0.001), DM nephropathy (OR = 4.8, p = 0.001), HbA1c ≥7% (OR = 4.3, p = 0.025) and duration of DM >5years (OR = 3.3, p = 0.012) were significantly associated with thyroid dysfunction in T2DM patients in this study.Conclusion: Female gender, central obesity, DM nephropathy, above normal HbA1c, and duration of DM were risk factors of thyroid dysfunction in type 2 DM patients in this study.

Highlights

Thyroid dysfunction is a spectrum of disorders of the thyroid gland which manifests either as hyperthyroidism or hypothyroidism and is reflected in the circulating levels of thyroid stimulating hormone (TSH) [1, 2]
This study focused on risk factors for thyroid dysfunction in type 2 diabetes mellitus (T2DM) patients and will add to the Nigerian literature, more so, as it is the first in South-East Nigeria
About 56.5% of the T2DM patients who participated in this study were females and 62.7% of the controls were females

Summary

Introduction

Thyroid dysfunction is a spectrum of disorders of the thyroid gland which manifests either as hyperthyroidism or hypothyroidism and is reflected in the circulating levels of thyroid stimulating hormone (TSH) [1, 2]. Low T3 levels have been observed in uncontrolled DM This has been ascribed to the impairment in peripheral conversion of T4 to T3 which normalizes with improvement in glycaemic control [5, 8]. Higher levels of circulating insulin associated with insulin resistance has been shown to have a proliferative effect on thyroid tissue resulting in larger thyroid size with increased formation of nodules [5, 9, 10]. This may lead to thyroid dysfunction (hyperthyroidism) in patients with type 2 DM. This study focused on risk factors for thyroid dysfunction in type 2 diabetes mellitus (T2DM) patients and will add to the Nigerian literature, more so, as it is the first in South-East Nigeria

Methods

Results

Conclusion