In addition, compared with the non-diabetes group, the diabetes group had higher serum GGT levels (24.0 vs. 19.0 U/L, p < 0.001) and higher serum ALT levels (13.0 vs. 12.0 U/L, p < 0.001), but with no significant difference for AST levels (19.0 vs. 18.0 U/L, p = 0.163). Here, GPT is linked to diabetes mellitus.