As long-term studies show, bariatric surgery gives people who suffer from morbid obesity a good chance of finding their way back to a healthy life. © Suzanne Tucker/Shutterstock

The results are impressive: after bariatric surgery (a gastric bypass, for instance) long-term positive effects were observed. They included not only a lasting reduction in weight, but also improvement in stability of the carotid vessels as well as in the genetic material and the performance of lipid metabolism. These were in brief the results of the FWF-funded study Long-Term Effects of Bariatric Surgery on Atherosclerosis. The medical team monitored 173 patients before and after bariatric surgery over a period of 10 years. “It has been shown”, notes principal investigator Christoph Ebenbichler from the Department for Internal Medicine I at the Medical University of Innsbruck, “that this type of intervention is highly successful and has lasting results.”

A silver bullet?

Surgery as the silver bullet for losing weight? A kind of panacea for a society that is increasingly tending to become obese? Ebenbichler cautions against exaggerated expectations. “All of our patients have a metabolic dysfunction.” That is to say, they are individuals suffering from morbid obesity, and their surplus weight can no longer be reduced by other measures such as diet or exercise. “This surgery is not for the average overweight person”, emphasises the physician in the interview with scilog. And the process is not at all a simple intervention: “The surgery is a central aspect, but the change in diet and the follow-up therapy, which may take years, are just as important.” In other words, this is a process that is extremely challenging for the patients - physically and mentally. The study was inspired by the simple but very significant question as to what prerequisites need to be fulfilled for undergoing such surgery. Bariatric surgery has been carried out in Innsbruck since 1994, and with increasing experience the requirements became stricter. The physicians also obtained new insights. “In 2001, Professor Herbert Tilg started a project on fatty livers, and that was the beginning of intensive investigations”, recalls Ebenbichler.

The quality of in-depth investigations

The study conducted in Innsbruck is not the largest one in Europe. In other countries and at other research institutions, studies have been made with significantly higher numbers of participants. “But we drilled down deeper, if you like”, explains Ebenbichler. His study starts with a detailed anamnesis, looking at prior weight curves, exploring current medication and complications arising in connection with bariatric surgery, but also including follow-up interventions, follow-up illnesses, ancillary ailments, as well as blood sampling to determine all clinically relevant metabolic parameters, and even a survey on current quality of life.

Three major outcomes

After 10 years and 173 persons examined, the physicians have been able to show that the wall thickness of the carotid artery remained stable. Wall thickness is an indicator for the risk of developing or dying of cardiovascular disease (cardiac infarction, stroke and atherosclerosis). The wall thickness of the blood vessel increases with age, excess weight, smoking and a sedentary lifestyle, all leading to heightened risk. Bariatric intervention puts an effective stop to this “natural” deterioration and lowers the risk of cardiovascular disease. In addition, bariatric surgery protects the genetic material. Every time a body cell divides, so-called telomeres form a protective layer around the genetic material to prevent attrition. With age, telomeres become shorter, a process that is reversed by bariatric surgery. And, finally, the surgery lowers the concentration of the PCSK-9 protein, which multiplies the number of blood lipid docking sites on the surface of liver cells. After bariatric surgery, the concentration of the protein drops in line with the bodyweight. This enables the liver to better absorb and process harmful blood lipids which could lead to cardiovascular disease.

Cost-effective after two years

“The positive effects are actually comprehensive – but they are all traceable to the reduction in body weight”, emphasises Ebenbichler. And this weight loss needs to be ascertained after the surgery. “The first 1 ½ years are the critical time, when patients start eating less and change their diet and lifestyle, and in which they take all sorts of medication. This is a very decisive period”, the physician continues. A good many patients are wary of undergoing such surgery because of these challenges, although health insurance “covers it generously”, as Ebenbichler notes. He explains that it is not a bad bargain for the insurance, because “after two years the investment proves cost-effective”.

Personal details Christoph Ebenbichler studied medicine in Innsbruck and, after several years of working at the Department of Medicine and Molecular Microbiology at the Washington University School of Medicine in St. Louis, USA, he returned to Innsbruck where he obtained his venia docendi for internal medicine at the Medical University of Innsbruck.

Publications and contributions

Laimer M, A Melmer, C Lamina, J Raschenberger, P Adamovski, J Engl, C Ress, A Tschoner, C Gelsinger, L Mair, S Kiechl, J Willeit, P Willeit, C Stettler, H Tilg, F Kronenberg, and C Ebenbichler: Telomere length increase after weight loss induced by bariatric surgery: results from a 10 years prospective study, International Journal of Obesity, 40(5), 773-8, 2016, DOI: 10.1038/ijo.2015.238
Melmer A, W Sturm, B Kuhnert, J Engl-Prosch, C Ress, A Tschoner, M Laimer, E Laimer, M Biebl, J Pratschke, H Tilg and C Ebenbichler: Incidence of gall stone formation and cholecystectomy 10 years after bariatric surgery, Obesity Surgery, 25(7), 1171-6, 2015, DOI: 10.1007/s11695-014-1529-y
Melmer A, C Lamina, A Tschoner, C Ress, S Kaser, M Laimer, A Sandhofer, B Paulweber and C F Ebenbichler: Body Adiposity Index and other indexes of body composition in the SAPHIR study: association with cardiovascular risk factors. Obesity, 21, 775-81, 2013, DOI: 10.1002/oby.20289
Tschoner A, W Sturm, C Gelsinger, C Ress, M Laimer, J Engl, E Laimer, G Mühlmann, R Mittermair, S Kaser, H Tilg and CF Ebenbichler: Long-term effects of pronounced weight loss after bariatric surgery on both functional and structural markers of atherosclerosis, Obesity, 21, 1960-5, 2013, DOI: 10.1002/oby.20357