Comorbidities may predict weight-loss success after gastric bypass
LOS ANGELES — Adults with certain comorbidities, including hypertension, dyslipidemia, type 2 diabetes and sleep apnea, are more likely to experience sustained weight loss in the 2 years after Roux-en-Y gastric bypass surgery than adults who do not have those conditions, according to recent study findings presented at ObesityWeek.
Prapimporn C. Shantavasinkul, MD, of the division of nutrition and biochemical medicine in the department of medicine at Ramathibodi Hospital and a faculty member at Mahidol University in Bangkok, said study results also showed that 19% of middle-aged adults who undergo Roux-en-Y gastric bypass will regain at least 15% of their 1 year before surgery weight back within 2 years.
Prapimporn C. Shantavasinkul
“Our findings underscored the complexity of mechanisms of weight regain,” Shantavasinkul said while presenting the findings. “Further prospective study is needed to explore the predictors and mechanisms of weight gain in order to minimize the problems.”
In a retrospective study, Shantavasinkul and colleagues analyzed data from 1,426 patients (84% women) who underwent Roux-en-Y gastric bypass at the Duke Center for Metabolic and Weight Loss Surgery in Durham, North Carolina, between 2000 and 2012. Adults included in the study had follow-up visits for at least 2 years after surgery and experienced at least 50% of their excess weight loss at 1 year after surgery.
Researchers divided the cohort into two groups. The “weight-regain” group (n = 244; mean age, 42 years; 89% women; 77% white) gained 15% or more of their 1-year postoperative weight loss; the “sustained weight-loss” group (n = 1,182; mean age, 46 years; 83% women; 77% white) maintained or gained less than 15% of their 1-year postoperative weight. The preoperative BMI for both groups was 48 kg/m2.
Researchers found that a longer duration after surgery was associated with weight regain (OR = 1.61; 95% CI, 1.51-1.71), with patients beginning to gain weight, on average, 2 years after surgery. The weight-regain group gained an average of 19.5 kg during a mean of 6 years after surgery; the sustained weight-loss group lost an average of 0.8 kg during a mean of 3.3 years after surgery.
Younger age was a significant predictor of weight regain (OR = 0.97; 95% CI, 0.96-0.98), even after adjusting for the length of time since surgery.
Among those in the sustained weight-loss group, more patients had hypertension (59.1% vs. 51.2%), dyslipidemia (31.5% vs. 19.3%), type 2 diabetes (25.3% vs. 23%), insulin-treated type 2 diabetes (8.9% vs. 4.5%) and sleep apnea (14% vs. 9.8%) compared with patients in the weight-regain group.
Shantavasinkul noted that some patients who did well after surgery may not have returned to the clinic for follow-up and were, instead, seen by their primary care physician. In addition, data regarding the resolution of any comorbidities after surgery, as well as diet, physical activity and psychological disorder data, were unavailable for this study.
“Regular follow-up with their bariatric surgeon is the point that we need to emphasize ... to avoid this phenomenon,” Shantavasinkul said. – by Regina Schaffer
Shantavasinkul PC, et al. Abstract #A104. Presented at: ObesityWeek; Nov. 2-6, 2015; Los Angeles.
Disclosure: Shantavasinkul reports no relevant financial disclosures.