Gastric stimulation for obesity
The Transcend Implantable Gastric Stimulator (IGS®) is a new health device that may help fight “globesity” — a World Health Organization term describing the escalating global epidemic of obesity.
The 60X40X10.3 mm device has insulated wires that run to the stomach wall.
Photo courtesy of Medtronic
The battery-operated device, made by Medtronic, is implanted under the skin of the abdomen and then attached to two insulated wires that are sutured to the stomach wall.[1]
The IGS sends painless electric pulses to the stomach, inducing an early and lasting sensation of “fullness,” possibly by regulating the gut hormones responsible for appetite.[1,2] The IGS is used in combination with diet and lifestyle modifications.[2]
The surgery
A bariatric surgeon (a physician who specializes in the treatment of obesity) makes a laparoscopic incision to implant the device, and the patient returns home the same day. The surgeon later activates and sets the electrical pulses with a computer and radio-electric wand.
Compared with other surgical options, such as gastric banding and gastric bypass, the IGS is less invasive and does not alter the anatomy or physiology of the gastro-intestinal tract.[3]
The evidence
More than 500 patients in randomized, placebo-controlled clinical trials lost an average of 32% of their excess weight after using the device for two years. No serious complications were reported.[4]
Regulatory status
The IGS was approved by Health Canada in December, 2004.[5] The IGS has been sold in Europe for more than three years, but is approved only for investigational use in the United States.[6]
The diagnosis of obesity is based on body mass index (BMI), which is a measure of a person’s weight in relation to their height.
An individual with a BMI of 30 or more is considered obese.[7]
Source: Statistics Canada
Who might benefit?
According to Health Canada, the IGS is indicated for weight reduction in obese adults with a BMI more than 35. Based on 2004 Statistics Canada data, approximately 1.9 million adult Canadians have a BMI equal to or greater than 35, which is associated with a high risk of high blood pressure, diabetes, and heart disease.[7]
Cost
According to Dustin Ide, senior vice-president of Canadian distributor Xycorp Medical Inc., the device costs C$11,500 and the surgical procedure may cost up to C$12,500. As the IGS is not covered by insurance (public or private), the patient is responsible for all associated costs.
Other developments
Other US companies are developing similar obesity implants that deliver an electrical charge to the stomach.
References
[1] Shikora SA. Obes Surg 2004;14 Suppl 1:S40-S48.
[2] Aronne LJ, et al. Obes Surg 2004;14 Suppl 1:S23-S27.
[3] Shikora SA. Obes Surg 2004;14 Suppl 1:S9-13.
[4] Miller K. Best Practice and Research in Clinical Gastroenterology 2004;18(6 Special issue):1147-65.
[5] Medical devices active license listing [database online]. Rev. Ottawa: Medical Devices Bureau, Therapeutic Products Directorate, Health Canada; 2004 Nov 24. Available: http://www.mdall.ca/.
[6] Medtronic. Medtronic acquires Transneuronix, Inc.: industry leader in electrical stimulation therapy for the treatment of obesity. Minneapolis, MN: Medtronic; 2005. Available: http://www.medtronic.com/obesity/.
[7] Tjepkema M. Measured obesity: adult obesity in Canada: measured height and weight. Ottawa: Statistics Canada; 2005. Available: http://www.statcan.ca/english/research/82-620-MIE/2005001/pdf/aobesity.pdf.