Today at an Obesity 2011 session on interventions and clinical studies, Dr. Ted Adams presented six-year follow-up data from The Utah Obesity Study. They found that after gastric bypass surgery (GBP), patients maintained significant weight loss and improvements in important cardiovascular and metabolic measures, when compared to severely obese control patients who did not undergo surgery.
1156 patients were included in this study, comprised of three groups: 418 morbidly obese patients who underwent GBP (the treatment group); 417 morbidly obese patients seeking GBP but who were unable to have it mainly due to lack of health insurance (control group1); and 321 morbidly obese patients randomly selected community controls from the Utah Health Family Tree Program (control group 2).
Patients underwent detailed evaluations at baseline and also at 2 and 6-year follow-up intervals. The investigators had excellent six-year follow-up of 96.8%. In the GBP group total weight reduction was 35% of initial body weight at 2 years, and this tapered off to 28% at 6 years follow up. Average weight loss in both non-surgery control groups was negligible.
The GBP patients experienced many significant health improvements compared to the control groups. At six years after GBP, diabetes was in remission in 75% of patients with an incidence of diabetes in the group of only 2%, compared to 1% remission and 16% incidence in the controls (both p<0.001). Surgery patients also experienced significant reduction in their “bad” cholesterol profiles (LDL and triglycerides) and had increased “good” cholesterol (HDL). Improvements in hypertension and also cardiac morphology, or physical changes to the heart, were also seen in GBP patients at six years: decreased left atrial volume, left atrial mass, and left ventricular volume, compared to the control groups. Dr. Adams hypothesized that these physical, measurable changes to the heart may result in a reduction in obesity-related heart failure in the long-term. In his summary, Dr. Adams stated that he thought that The Utah Obesity study was a good complement to other large cohort studies of bariatric surgery. He felt it added to the Swedish Obese Subjects (SOS) study since that focused on vertical banded gastroplasty (a procedure rarely performed now), and it also complemented the Longitudinal Assessment of Bariatric Surgery (LABS) study, since it lacks a control group of patients not undergoing weight loss surgery.