Figure 4 summarizes the obtained meta-analysis results. The pooled studies for the analysis assessing serum visfatin levels in NASH patients and simple steatosis patients demonstrated an overall MD of −7.906 (95% CI −29.480–13.667). Substantial heterogeneity was reported with an I2 = 96.55% and p-value < 0.001. The gene discussed is NAMPT; the disease is metabolic dysfunction-associated steatohepatitis.