The treatment of diabetic gastroparesis with botulinum toxin injection of the pylorus

OBJECTIVE: Gastroparesis is a disorder of delayed gastric emptying that is often chronic in nature. Up to 50% of type 1 diabetic subjects have symptoms of gastroparesis, which include nausea, vomiting, and early satiety. Elevated pyloric pressures may be responsible for delayed gastric emptying in diabetic subjects. Botulinum toxin inhibits the release of acetylcholine and produces transient paralysis when injected into smooth muscle. The aim of this study was to determine whether injection of the pylorus with botulinum toxin in patients with diabetic gastroparesis improves symptoms of gastroparesis, alters gastric emptying scan time, and/or changes weight and insulin use. RESEARCH DESIGN AND METHODS: This was an open-label trial with age- and sex-matched control subjects from a tertiary care referral center for patients with gastroparesis. Eight type 1 diabetic subjects (six women and two men; mean age 41 years; mean years with diabetes 25.3) who had failed standard therapy were enrolled. Intervention consisted of injection of the pylorus with 200 units of botulinum toxin during upper endoscopy. Symptoms, antropyloric manometry, gastric emptying scan times, weight, and insulin use were all recorded before intervention and during a 12-week follow-up period. RESULTS: Seven of the eight patients completed the full 12-week follow-up period. No complications were noted. Mean symptom scores declined from 27 to 12.1 (P < 0.01), whereas the SF-36 physical functioning domain also improved (P < 0.05). Four patients noted an increase in insulin use of >5 units/day. Six of the seven patients gained weight (P = 0.05). Gastric emptying scan time improved in four patients. CONCLUSIONS: Botulinum toxin injection of the pylorus is safe and improves symptoms in patients with diabetic gastroparesis. These results warrant further investigation with a large, double-blind, placebo-controlled trial.