Serum Tsukushi Level Is Associated With the Severity of Liver Fibrosis Independent of Type 2 Diabetes

Tsukushi (TSK) is a recently identified hepatokine, and we aimed to investigate the association between systemic TSK and the severity of nonalcoholic fatty liver disease (NAFLD) in subjects with and without type 2 diabetes mellitus (DM).

Three hundred ninety-three DM and 289 without DM individuals were recruited for transient elastography assessment to determine liver steatosis and fibrosis. Serum TSK was measured by ELISA. The presence of NAFLD was defined as controlled attenuation parameter ≥ 248 dB/m.

NAFLD was present in 276 (70.2%) and 129 (44.6%) subjects with and without DM respectively, and they had higher serum TSK levels than those without NAFLD [DM group: 91.0 ng/mL (61.7-133.8) vs 82.5 (60.9-118.5), P < .01 respectively; without DM group: 97.1 ng/mL (69.3-148.6) vs 80.8 (53.4-111.6) respectively, P < .01]. Univariate analysis showed that serum TSK significantly correlated with the degree of steatosis and fibrosis both in subjects with and without DM. On multivariable regression analysis, only liver stiffness and estimated glomerular filtration rate were significant determinants of TSK level, and the relationship was independent of diabetes and serum adiponectin. Out of 405 subjects with NAFLD, 49 had either advanced fibrosis or cirrhosis. The area under receiver operating characteristic curve of serum TSK to indicate advanced fibrosis or cirrhosis was 0.70 (95% CI .62-.77), which was significantly better than that of fibrosis-4 index, 0.64 (95% CI .55-.72), P < .05.

Serum TSK levels were increased in subjects with NAFLD and reflected the severity of liver fibrosis.