Changes in serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease

Objective To investigate the changes in the serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease( NAFLD). Methods A total of 68 NAFLD patients who were admitted to The Eighth People' s Hospital of Shanghai from July 2014 to April 2016 were enrolled as NAFLD group,and 70 healthy persons who underwent physical examination were enrolled as healthy control group. Among the 68 patients in the NAFLD group,24 had NAFLD alone and 44 were complicated by abnormal alanine aminotransferase( ALT) level. The levels of aspartate aminotransferase( AST),ALT,total cholesterol( TC),triglyceride( TG),and serum markers of iron metabolism [serum iron( SI),serum ferritin( SF),and serum hepcidin( HEPC) ] were measured for all patients,and the correlations between abnormal ALT level and serum markers of iron metabolism were analyzed. The independent samples t- test was used for comparison of continuous data between groups,the chi- square test was used for comparison of categorical data between groups,and the Pearson correlation coefficient was used to investigate the correlation between two variables. Results The NAFLD group had significantly higher body mass index and serum levels of ALT,AST,TC,and TG than the healthy control group( t = 9. 8,8. 6,8. 5,9. 2,and 2. 7,all P < 0. 05). Compared with the healthy control group,the NAFLD group had significantly higher levels of SI( 21. 7 ± 7. 1 μmol/L vs18. 7 ± 6. 9 μmol/L,t = 2. 3,P = 0. 02) and SF( 340. 2 ± 257. 6 μg/L vs 119. 1 ± 81. 2 μg/L,t = 6. 7,P < 0. 01) and a significantly lower level of HEPC( 12. 2 ± 5. 3 μg/L vs 22. 2 ± 6. 5 μg/L,t = 9. 9,P < 0. 01). Compared with those with NAFLD alone,the patients complicated by abnormal ALT level had significantly higher serum levels of ALT( 89 ± 58 U/L vs 26 ± 8 U/L,t = 7. 1,P < 0. 01),SI( 23. 4 ± 6. 2 μmol/L vs 19. 6 ± 7. 9 μmol/L,t = 2. 2,P = 0. 03),and SF( 406. 2 ± 290. 0 μg/L vs 219. 4 ± 112. 0 μg/L,t = 3. 7,P <0. 01),as well as a significantly lower serum level of HEPC( 7. 4 ± 4. 9 μg/L vs 16. 1 ± 7. 8 μg/L,t = 4. 7,P < 0. 01). The Pearson correlation analysis showed that SF was significantly positively correlated with ALT and AST( r = 0. 28 and 0. 34,P = 0. 02 and P < 0. 01).Conclusion NAFLD patients have significant iron overload,especially in NAFLD patients complicated by abnormal ALT level. SF is significantly positively correlated with ALT and AST. To a certain degree,SF can reflect the severity of liver injury in NAFLD patients.