Hypoleptinemia in Gastric Cancer Patients: Relation to Body Fat Mass, Insulin, and Growth Hormone

Abstract
Background: It remains elusive whether there are other causes besides body fat mass wasting contributing to decreased leptin level in cancer cachexia patients. This study attempts to explore possible factors influencing leptin levels in patients with gastric cancer. Methods: Hormones levels (including leptin, insulin, growth hormone (GH), insulin-like growth factor I, glucagons, and cortisol), acute phase reactant, and body composition were measured in 88 gastric cancer patients and 24 healthy controls. All patients were divided into weight-loss (48 patients) or nonweight-loss (40 patients) groups and cachexia (body mass index Results: Compared with the controls, leptin levels decreased in gastric cancer patients with and without weight loss (p < .001 and p = .003, respectively), even when the percentage of fat mass was adjusted (p = .004 and 0.018, respectively). GH and insulin levels also changed significantly. Similar results were also found in patients with and without cachexia. Multivariate regression analysis showed that the percentages of fat mass (standardized coefficient [SC] = 0.631, p < .001), GH (SC = –0.244, p = .005) and insulin (SC = 0.201, p = .020) were significantly correlated with leptin. In the 16 patients who underwent radical surgery, leptin levels remained low and no significant changes in the other hormones were detected.Conclusions: Our results showed that low leptin levels in gastric cancer patients depended not only on the percentage of fat mass, but also on GH and insulin levels. Chronic high GH and low insulin levels may inhibit the leptin secretion.