Association between adipose insulin resistance, serum lipoprotein(a) level, and MASLD in adult patients with T2DM in China.

Introduction: The aim was to explore the correlation between adipose tissue insulin resistance and metabolic dysfunction-associated steatotic liver disease (MASLD), and to assess how the serum lipoprotein(a) [Lp(a)] level modifies the association between adipose insulin resistance and MASLD.

Material and methods: We analyzed hospitalized type 2 diabetes mellitus (T2DM) patients and calculated the adipose insulin resistance (Adipo-IR) index as the product of the fasting insulin and free fatty acid concentration. There were 2247 participants in the study, 64.6% (n = 1452) with MASLD.

Results: Compared to subjects in the first quartile of the Adipo-IR index, there were 1.29 [odds ratio (OR): 2.29, 95% confidence interval (CI): 1.56-3.36], 2.55 (OR: 3.55, 95% CI: 2.34-5.37), and 2.00 (OR: 3.00, 95% CI: 1.94-4.63) fold higher odds of having MASLD among subjects in the second, the third, and the fourth Adipo-IR index quartile, respectively. As the Adipo-IR index was in the range lower than 7.5, Adipo-IR was a risk factor for MASLD (OR: 1.349, 95%CI: 1.226-1.484). Conversely, if the Adipo-IR index was higher than 7.5, it became a protective factor for MASLD (OR: 0.980, 95% CI: 0.964-0.997). Subjects with high Lp(a) and low Adipo-IR showed the lowest risk of MASLD. Compared to this group, the ORs of MASLD was 2.411 (95% CI: 1.590-3.656) for the high Adipo-IR and low Lp(a) group, 2.770 (95% CI: 1.808-4.246) for the high Adipo-IR and high Lp(a) group, and 1.473 (95% CI: 1.003-2.164) for the low Adipo-IR and low Lp(a) group.

Conclusions: In patients with T2DM, with the increase of Adipo-IR, the incidence of MASLD showed a trend of first an increase and then a decrease. Among patients with T2DM, those with low Adipo-IR combined with high Lp(a) had the lowest risk of developing MASLD.