Prevalence of Hypothyroidism in Patients with Nonalcoholic Fatty Liver Disease

Research Article

Annals Thyroid Res. 2020; 6(1): 247-250.

Prevalence of Hypothyroidism in Patients with Nonalcoholic Fatty Liver Disease

Karami P1, Shahverdi E2, Abbas Saadat S3, Houshmand R4, Bazireh H5, Masoumi A6, Manouchehri R6, Vakiloroaya Y6* and Gilardoni RDS7

1Department of Otorhino Laryngology-Head and neck Surgery, Iran University of Medical Sciences, Iran

2Department of Cardiology, Angiology and Sleep Medicine, Bonifatius Hospital, Germany

3Carl von Ossietzky University, Germany

4Department of Genetics, Islamic Azad University, Iran

5Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Iran

6Young Researchers and Elite Club, Islamic Azad University, Iran

7Department of Gastroenterology and Diabetology, Bonifatius Hospital, Germany

*Corresponding author: Yasaman Vakiloroaya, Young Researchers and Elite Club, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran

Received: July 06, 2020; Accepted: August 07, 2020; Published: August 14, 2020


Aim: We determined the prevalence of hypothyroidism in a cohort of patients with Nonalcoholic Fatty Liver Disease (NAFLD) and analyzed the potential factors associated with hypothyroidism in this patient population.
Methods: Two hundred and forty-six patients with proven NAFLD attending hepatology clinics from October 2012 to June 2017 and 430 age, gender, race and BMI matched control subjects seen in the general internal medicine clinic were included. Patients with a clinical diagnosis of hypothyroidism who were on thyroid replacement therapy were hypothyroid.

Results: Hypothyroidism was more frequent among patients with NAFLD (21%vs 9.5%.; P<0.01) compared to controls and was higher in NASH patients than NAFLD patients without NASH (25% vs 12.8%, P=0.03). Subjects with hypothyroidism were 2.1 (95% CI: 1.1, 3.9, P=0.02)) and 3.8 (95% CI:2,6.9, P<0.001) times more likely to have NAFLD and NASH respectively. By Multivariate analysis, female gender (P<0.001) and increased BMI (P=.03) were associated with hypothyroidism. NAFLD with mild alcohol consumption were less likely to have hypothyroidism compared to those who reported complete abstinence (OR 0.37, P=0.008).
Conclusions: This study showed a higher prevalence of hypothyroidism in patients with NAFLD compared to controls. It was also demonstrated that patients with hypothyroidism were more likely to have NASH.
Keywords: Nonalcoholic fatty liver disease; NAFLD; Hypothyroidism 


Massive collection of triglycerides and free fatty acids in the liver is identified as Nonalcoholic Fatty Liver Disease (NAFLD) [1]. NAFLD is considered as the most widespread liver disorder in developed and developing countries [2,3] and there has been a surge of interest in NAFLD, since it is estimated to be the leading cause of liver associated mortality by 2030. According to preceding research, NAFLD is a multi-system disease and has directly significant impact on both liver and cardiovascular system [4]. Further, there is a strong association between NAFLD and metabolic syndrome [5,6]. Based on last studies, thyroid dysfunction especially hypothyroidism associate with components of the metabolic syndrome include insulin resistance [7,8], dyslipidemia [9] and obesity [10].

Surprisingly, hyperthyroidism has resemblance to NAFLD in some features such as dyslipidemia, decreased fatty acid oxidation, and increased hepatic lipid peroxidation and insulin resistance [11]. Therefore, there is likely to be an association between thyroid abnormality and NAFLD. However, clinical data supporting that this association are incomplete and the pathophysiology is unclear. To date, very little research has been conducted about thyroid function and NAFLD in Iran. This study was conducted to investigate the relationship between nonalcoholic fatty liver disease and thyroid abnormalities to assess its impact on thyroid gland function tests in the Iranian general population.

Material and Methods

Study design and patient population

This study was a descriptive study, which was approved by our ethics committee. Individuals were asked to sign an informed consent form before blood samples obtaining. All the terms of the Helsinki declaration were considered, and the personal information remained anonymous. The study population consisted of 1340 adult patients individuals at least ≥18 years of age with proven Nonalcoholic Fatty Liver Disease (NAFLD) by a gastroenterologist with 10 years of experience, seen in the gastroenterology outpatient clinics October 2012 to June 2017.

Detailed medical history, clinical examination, anthropometric assessment and laboratory tests were evaluated. Height and body weight were measured and Body Mass Index (BMI) was calculated as follows: BMI= body weight (kg)/ height squared (m2). The normal range of BMI is 19-24.9 kg/m2, overweight is 25-29.9 kg/m2, and obesity ≥30 kg/m2. All routine investigations were done after a 12-hour overnight fast. Baseline thyroid functions (FT4 and TSH) were measured. Other lab tests included liver function tests, lipid profile and serum albumin. NAFLD was diagnosed as presence of fatty liver by ultrasonography in the absence of excess alcohol intake (>20 g/day).

Citation: Karami P, Shahverdi E, Abbas Saadat S, Houshmand R, Bazireh H, Masoumi A, et al. Prevalence of Hypothyroidism in Patients with Nonalcoholic Fatty Liver Disease. Annals Thyroid Res. 2020; 6(1): 247-250.