[Role of duodenum in regulation of plasma ghrelin level and body mass index after subtotal gastrectomy].

Objective: To investigate the role of duodenum in regulation of ghrelin and body mass index (BMI) and the correlation between ghrelin and BMI after subtotal gastrectomy.

Methods: Forty-two patients with T(0-1)N(0-1)M(0) gastric cancer were divided into two groups after gastrectomy according to digestive reconstruction pattern, Billroth I group (n=23) and Billroth II group (n=19) respectively. Plasma ghrelin levels were determined by radioimmunoassay (RIA) before and at day 1, 7, 30 and 360 after gastrectomy,and BMIs were also measured.

Results: Two groups had identical postoperative trends in ghrelin alterations during the early stage, both dropping to nadir at day 1 (36.7% vs 35.7%), then markedly increasing at day 7 (51.0% vs 51.1%). At day 30, ghrelin level of Billroth I group was slightly higher than that of Billroth II group. At day 360, ghrelin level of Billroth I group recovered to 93.6%, approaching though lower than preoperative level and no significant difference was displayed, while ghrelin level of Billroth II group recovered only to 81.6% of preoperational level and significant difference existed (P=0.033). Compared with preoperative levels, ghrelin of two groups decreased by 6.9% and 18.4% while BMI by 3.3% and 6.4% respectively, liner regression correlations were revealed in both groups between decrease magnitudes(R(1)(2)=0.297,P=0.00;R(2)(2)=0.559,P<0.001).

Conclusions: Anatomico-physiological duodenum compensatively promotes ghrelin recovery, accordingly enhances BMI after gastrectomy. Regarding patients with insufficient ghrelin secretion, ghrelin is positively correlated with BMI.