Prevalence of Hypothyroidism in Nonalcoholic Fatty Liver Disease

Abstract

Background A possible association between nonalcoholic fatty liver disease (NAFLD) and hypothyroidism has been suggested. Possible explanations for this association are the recognized links between hypothyroidism and various elements of the metabolic syndrome which is often present in NAFLD. To further explore this association, we determined the prevalence of hypothyroidism in a cohort of patients with NAFLD and analyzed the potential factors associated with hypothyroidism in this patient population. Methods Two hundred and forty six patients with biopsy proven NAFLD attending hepatology clinics at the Cleveland Clinic between October 2006 to June 2009 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 considered to be 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 subjects who reported mild alcohol consumption were less likely to have hypothyroidism compared to those who reported complete abstinence (OR 0.37, P=0.008). Conclusions A higher prevalence of hypothyroidism was demonstrated in patients with NAFLD compared to controls. Patients with hypothyroidism were more likely to have NASH. Among subjects with NALFD, female gender, increased BMI and history of abstinence from alcohol were associated with hypothyroidism. Further studies are needed in order to confirm and better characterized these findings as well as the described associations and their pathogenesis.

Editorial: Non-Alcoholic Fatty Liver Disease and Obesity: Not All About Body Mass Index

“…Although the authors appropriately matched the postmenopausal status, another possible confounder could have been the role of thyroid disorders in women. As recently shown ( 20 ), there is an increased prevalence of hypothyroidism in patients with NAFLD compared with controls without NAFLD ( 20 ). Th e association between NAFLD and hypothyroidism was stronger in women than in men.…”

Mechanisms in endocrinology: Non-alcoholic fatty liver disease in common endocrine disorders

“…The prevalence of hypothyroidism among a cohort of 246 patients with biopsy-proven NAFLD was 21 vs 9.5% in 430 age-, gender-, race-and BMI-matched controls (90). In addition, the prevalence of hypothyroidism in patients with NASH is higher than those with more benign disease (90,91). There are currently no published studies that have examined NAFLD in the context of hyperthyroidism.…”

Fatty liver largely explains associations of subclinical hypothyroidism with insulin resistance, metabolic syndrome, and subclinical coronary atherosclerosis

“…Although some studies have reported associations of SCH with insulin resistance (7,8), metabolic syndrome (MS) (7,9), and CHD (10,11), not all previous findings have been consistent (12,13,14). Recent studies in adults (9,15,16) and children (7) have shown that SCH is closely associated with NAFLD independent of potential confounders. Based on these findings and considering that insulin resistance is a key feature of NAFLD, we hypothesized that the relationship of SCH with cardiometabolic risk factors and CHD may be influenced by the presence of increased intrahepatic fat.…”