Thyroid dysfunction and insulin resistance in patients with nonalcoholic fatty liver disease

• Main Authors: Maha Assem, May Fawzi, Alhosaeyn Ibrahim, Aasem Saif
• Format: Article
• Language: English
• Published: SpringerOpen 2018-01-01
• Series: The Egyptian Journal of Internal Medicine
• Subjects: autoimmunity; insulin resistance; nonalcoholic fatty liver; thyroid
• Online Access: http://www.esim.eg.net/article.asp?issn=1110-7782;year=2018;volume=30;issue=3;spage=97;epage=102;aulast=Assem
• ISSN: 1110-7782; 2090-9098

Introduction Nonalcoholic fatty liver disease (NAFLD) is a common cause of impaired liver functions. It is associated with hepatic and adipose tissue insulin resistance (IR) as well as decreased whole-body insulin sensitivity. Thyroid hormones are important for the intrahepatic metabolism of lipids. Thyroid disorders have been associated with IR owing to various mechanisms such as altered insulin secretion and lipid levels. Aim The aim of our study was to assess thyroid functions, thyroid autoimmunity, and IR in nondiabetic patients with NAFLD. Materials and methods The study was conducted on 90 nondiabetic participants (60 patients with NAFLD and 30 participants with normal liver). Both groups were sex matched. Ultrasonography was used to categorize the study participants into NAFLD and normal liver groups. Thyroid functions and thyroid peroxidase antibody were assessed in all participants. Homeostatic model assessment (HOMA IR) was used to assess IR in the study population. Results Our results showed a significantly higher HOMA IR in the NAFLD compared with the normal liver group (P<0.001). Moreover, significantly higher percentage of patients with NAFLD have IR (HOMA IR) compared with the normal liver group (56.7 vs. 6.7%, respectively; P<0.001). Our results also showed higher percentage of thyroid dysfunction in patients with NAFLD compared with individuals without NAFLD (P<0.02). Overall, 22 (36.7%) 60 patients in the NAFLD group versus three (10%) of 30 patients in the non-NAFLD group had subclinical hypothyroidism. Thyroid functions did not show any statistically significant correlations with IR, but thyroid peroxidase antibody showed significant positive correlation with IR (P<0.02) within the total study population. Conclusion There is an increased prevalence of subclinical hypothyroidism in nondiabetic patients with NAFLD who also have higher IR. The role of thyroid autoimmunity in this relationship needs further assessment.