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

OBJECTIVES: 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. METHODS: 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 of <70 g/week in women and <140 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. RESULTS: 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. CONCLUSION: 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.