GSTM1 and duodenal ulcer: The levels of serum nutritional indicators [hemoglobin (Hb), albumin (ALB), and total protein (TP)], feeding compliance rate, the incidence of complications (gastric retention, bloating, diarrhea, reflux, vomiting, aspiration, stress ulcers, etc.), and prognosis during the observation period were compared between the two groups.