Serum levels of immunoglobulins in an adult population and their relationship with nonalcoholic fatty liver disease

Few studies have reported the association between nonalcoholic fatty liver disease (NAFLD) and immunoglobulins. In this study, we aimed to investigate the relationship between serum immunoglobulin levels and NAFLD in a Chinese adult population.We performed a cross-sectional study including 11 261 Chinese adults. NAFLD was diagnosed based on the Chinese Guidelines for the diagnosis and treatment of fatty liver diseases and an alcohol intake of70 g/week in women and140 g/week in men, and serum immunoglobulin (Ig) levels were determined using immune nephelometry. Multiple logistic regression analysis was done to assess relationships between concentrations of serum immunoglobulins and NAFLD.Of the 11 261 adults recruited from January 2010 to December 2015, the prevalence of NAFLD was 40.8% (n = 4598). The geometric mean levels of IgG, IgM, IgE and IgA were 1177.49 mg/dL (95% confidence interval [CI] 1173.07-1181.93), 93.56 mg/dL (95% CI 92.70-94.42), 30.70 IU/mL (95% CI 29.92-31.49) and 216.64 mg/dL (95% CI 214.95-218.34), respectively. Compared with the lowest quintile, the multivariable adjusted odds ratio (95% CI) of NAFLD for the highest quintile of IgG, IgM, IgE, and IgA were 0.78 (0.66-0.92), 0.71 (0.60-0.84), 0.98 (0.84-1.15) and 1.41 (1.21-1.66), respectively.Increased IgA and decreased IgG and IgM levels are independently associated with NAFLD prevalence. Further research is needed to explore the causal association between serum immunoglobulins and NAFLD.