Serum ghrelin, but not obestatin, is a potential predictor of acute pancreatitis severity

The roles of ghrelin and obestatin in AP remain controversial. This study investigates the effects and the predictive value of serum ghrelin and obestatin levels in the early stage of AP. A total of 193 consecutive patients with AP and 24 healthy controls were included. Patients were divided into mild acute pancreatitis (MAP), moderately severe acute pancreatitis (MSAP), and severe acute pancreatitis (SAP) groups. Serum levels of ghrelin and obestatin were measured on the first, third, and fifth days of hospitalization. The predictive value of serum ghrelin and obestatin levels on the first day in AP was examined using receiver-operating characteristic (ROC) curves. On the first day of hospitalization, the mean serum ghrelin level was significantly lower in patients with AP than in controls (P < .01). The serum ghrelin concentration decreased with increasing AP severity and was lower in patients with SAP than in those with MAP and MSAP (P < .05). It increased gradually from the first to the fifth day after treatment. ROC curves demonstrated that the serum ghrelin level on the first day had some predictive value for AP severity (area under the ROC curve = 0.646), with an optimal cut-off value of 87.83 pg/mL. Logistic regression showed that the serum ghrelin level had independent predictive value for non-MAP (odds ratio = 10.94; 95% confidence interval, 5.08–23.55; P < .01). The serum obestatin level did not differ significantly between patients with AP and controls and had the limited predictive value for non-MAP (area under the ROC curve = 0.564). However, the serum obestatin concentration showed a “warning” effect regarding AP etiology; on the first day of treatment, it was significantly lower in patients with AP of hypertriglyceridemic etiology than in those with AP of biliary, alcohol-related, and other etiologies (P = .05, P = .031, and P = .029, respectively). Serum ghrelin and obestatin levels may be related to the progression of AP in the early stage. Only the serum ghrelin level is a potential predictor of AP severity in the early stage. Obestatin may be involved in the pathogenesis of AP caused by hypertriglyceridemia.