The mediation effect of liver and anthropometric indices on the relationship between incidence of diabetes and physical activity: results of 5-year follow up azar cohort study.

Background: It has been documented that regular physical activity is considered one of the most effective strategies for preventing diabetes; however, it is not the sole contributing factor. Therefore, we decided to evaluate the meditation effect of liver function and anthropometric indices on the relationship between incidence of diabetes and physical activity (PA) in the Azar cohort population.

Materials And Methods: Subjects who were diabetic in the baseline phase from 15,006 participants in study of azar cohort population were excluded and to follow up, a total of 13,253 people was included in the analysis. Demographic characteristics, physical activity, 10 anthropometric indices (AI) and seven liver indices (LI) were measured. Evaluated and displayed using Pearson correlation heatmap and canonical correlation of liver and anthropometric indices. The Generalized Structural Equation Modeling (GSEM) with the Maximum Likelihood method employed to estimate the model.

Results: During the follow-up years, a total of 685 participants developed diabetes. The measurements of the AI were significantly higher in subjects with diabetes (P < .001). Patients with diabetes were older, had a higher proportion of women, and had lower values of PA (P < .05). Body Roundness Index (BRI) and Waist height ratio (WHtR) exhibited the largest AUCs for predicting diabetes onset risk (both AUC = 0.6989) among these anthropometric measures. The increase in AI (RR [95%CI] = 1.25 [1.22,1.29], P < .001) and liver enzyme (LE) (RR [95%CI] = 1.14 [1.08.1.19], P < .001) increase the risk of diabetes by 25% and 14%, respectively. Despite the mediation effects of AI and Liver Enzymes for an increase of one MET of PA, the risk of developing diabetes decreases by 5% (RR [95% CI] = .95 [.92,.99], P = .013). Around VAF = 53% of the association between PA and diabetes onset (Total effect: RR [95% CI] = .90 [.87,.94], P < .001) was mediated by AI and LE.

Conclusions: A low level of PA was found to be significantly correlated with high levels of AI and LI, all of which are associated with an increased risk of developing diabetes. These analyses provide evidence that when the relationship between PA and diabetes is mediated by AI and LI this association becomes stronger, with AI playing a more significant role than LI.