Study Roundup

Published in February Issue             

Cost-effectiveness of Bariatric Surgery in Adolescents With Obesity (JAMA Surgery)

Published results from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study were used to assess the cost-effectiveness of bariatric surgery for adolescents with obesity. Procedure-related outcomes were reviewed at 3, 4 and 5 years following surgery for 228 patients whose mean age was 17 and mean BMI was 53 (range: 34-88). Data was also reviewed for quality-adjusted life-years (QALYs), total costs (in US dollars adjusted to 2015-year values), and incremental cost-effectiveness ratios (ICERs). A willingness-to-pay a threshold of $100,000 per QALY was used to assess cost-effectiveness. After 3 years, surgery led to a gain of 0.199 QALYs compared with no surgery at an incremental cost of $30,747, yielding an unfavorable ICER of $154,684 per QALY. When the clinical study results were extrapolated to 4 years, the ICER decreased to $114,078 per QALY and became cost-effective by 5 years with an ICER of $91,032 per QALY. The findings suggest bariatric surgery incurs substantial initial cost and morbidity, but surgery could be a cost-effective treatment for adolescents with severe obesity if assessed over a time horizon of 5 years. The investigators note that the study “underscores the need for long-term clinical trials in adolescents with at least 5 years of follow-up data.”

Bariatric Surgery in Women of Childbearing Age, Timing Between an Operation and Birth, and Associated Perinatal Complications (JAMA Surgery)

To examine the risk for perinatal complications in women with a history of bariatric surgery, a retrospective cohort study at hospitals in Washington state compared postoperative mothers to mothers without a history of bariatric surgery (nonoperative mothers) and analyzed the association of the operation-to-birth (OTB) interval with perinatal outcomes. Data was collected from birth certificates and maternally linked hospital discharge information from January 1, 1980, to May 30, 2013 for postoperative mothers and their infants (n = 1859). A population-based random sample of nonoperative mothers and their infants were frequency-matched by delivery year (n = 8437). Compared with infants from nonoperative mothers, infants from postoperative mothers had a higher risk for prematurity (14.0% vs 8.6%), neonatal intensive care unit (NICU) admission (15.2% vs 11.3%), small for gestational age (SGA) status (13.0% vs 8.9%), and low Apgar score [<=8] (17.5% vs 14.8%). Compared with infants from mothers with greater than a 4-year OTB interval, infants from mothers with less than a 2-year interval had higher risks for prematurity (11.8% vs 17.2%), NICU admission (12.1% vs 17.7%), and SGA status (9.2% vs 12.7%). OTB intervals of less than 2 years were associated with higher risks for prematurity, NICU admission, and SGA status compared with longer intervals. The investigators note the study findings could inform decisions regarding the optimal timing between an operation and conception.

The Elipse Balloon, a Swallowable Gastric Balloon for Weight Loss Not Requiring Sedation, Anesthesia or Endoscopy: A Pilot Study with 12-Month Outcomes (SOARD)

A prospective, non-randomized open trial assessed 12-month safety and efficacy outcomes of the Elipse Balloon, a swallowable gastric balloon for weight loss that can be deployed without the use of endoscopy or anesthesia. Twelve patients participated in the trial and received diet and exercise counseling during the balloon-therapy period (0-4 months). Eight months later they were seen in clinic to assess 12-month outcomes. There were seven (58.3%) females and five (41.7%) males. The mean age was 41, mean BMI was 35.9, mean weight was 103.5kg, and mean waist circumference was 117.6cm. Eleven (91.7%) balloons were filled and were included in subsequent analysis. All balloons were excreted safely and there were no serious adverse events. Accommodative symptoms were not severe and of very short duration. Mean %EWL and %TBWL was 50.2% and 14.6% at balloon excretion and 17.6% and 5.9% at 12 months. There was a statistically significant improvement in patients’ weight, BMI, body fat, waist circumference, diastolic blood pressure, HbA1c, cholesterol, TSH, AST, and ALT at balloon excretion. Quality of life was significantly improved at excretion
and 12 months.

Improvement of Voiding Characteristics in Morbidly Obese Women After Bariatric Surgery:
A Single-Center Study with a 1-Year Follow-up

To demonstrate the benefit of lower urinary tract symptoms (LUTS) and improvements in urinary incontinence after bariatric surgery, 183 women who had bariatric surgery at a single center were assessed for voiding dysfunction during preoperative and 1-year post-operative evaluation from August to December 2012. The mean age of patients was 38.5 and their baseline mean BMI was 37.5 (68.4% were over BMI 35). One year after gastric bypass, BMI showed a significant change, 9.5-point reduction (63.1% were below BMI 28). For specific characteristic changes in voiding status, Prostate Symptom Score (IPSS), Quality of life (QoL) score, an Overactive Bladder Symptom Score (OABSS), a patient perception of bladder score (PPBS) revealed significant improvement over baseline. For stress-related urinary incontinence (SUI), preoperative evaluation demonstrated the prevalence of SUI to be 40.74%, and 18.51% post-operatively. At a 1-year post-operative follow-up, the finding demonstrate significant improvements in voiding status.

Trends in Utilization of Bariatric Surgery, 2010-2014: Sleeve Gastrectomy Dominates (SOARD)

A review of the American College of Surgeons National Surgical Quality Improvement Program database was performed to analyze the changing pattern of bariatric surgery utilization from 2010 to 2014. A total of 93,328 primary surgery patients were included (age of 44.6±11.8 years and BMI of 46.2±7.9 kg/m2). Roux-en-Y gastric bypass (RYGB), adjustable gastric band, and SG comprised 58.4%, 28.8%, and 9.3% of the procedures in 2010 which changed to 37.6%, 3.1%, and 58.2% in 2014, respectively. Baseline BMI of SG patients decreased from 47.5 to 45.6 kg/m2. The proportion of diabetic patients undergoing RYGB increased (30.4% to 33.2%) but decreased among those having SG (26.6% to 22.8%). The proportion of patients with hypertension having RYGB remained unchanged while decreased among SG patients (56.2% to 47.6%). Female patients among the SG group increased from 73.2% to 77.7%. The findings reveal that SG has been increasingly performed in the United States superseding adjustable gastric band and RYGB and a trend is in favor of females, lower BMI, and lower ratio of patients with diabetes and hypertension.

Five-Year Outcomes After Vertical Sleeve Gastrectomy for Severe Obesity: A Prospective Cohort Study (Obesity Surgery)

Prospectively collected data was assessed on patients who had vertical sleeve gastrectomy (VSG) from December 2005 to November 2010 to evaluated 5-year outcomes including complications and revisions, weight change and obesity-related disease resolution. Health-related quality of life (HRQOL) was assessed retrospectively. Of 168 patients, 92% completed 2-year and 82% 5-year follow-up. Re-intervention for complications occurred in four patients, whereas revision surgery was performed in six patients for weight regain and in one patient for gastroesophageal reflux disease (GERD). Mean BMI decreased from 46.2 at baseline to 30.5 at 2 years and 32.9 at 5 years. Remission of type 2 diabetes mellitus and hypertension occurred in 79 and 62% at 2 years, and 63 and 60% at 5 years, respectively. The percentage of patients treated for GERD increased from 12% preoperatively to 29% at 2 years and 35% at 5 years. Physical and mental summary scores showed significantly better HRQOL at 5 years compared with the baseline cohort, but did not reach population norms.

Predictors of Physical Activity After Gastric Bypass — A Prospective Study (Obesity Surgery)

To identify self-regulatory predictors of physical activity after bariatric surgery questionnaire data was obtained in a prospective cohort of 230 patients 1 year after Roux-en-Y gastric bypass. A cohort of participants also agreed to wear an accelerometer for seven consecutive days, 18–24 months after surgery (n = 120). Mean age was 46.8 years. Preoperative and postoperative BMI was 44.8 and 30.6, respectively. Total weight loss was 28.9%. By objective measures, 17.9% of the participants met the recommended level of moderate-to-vigorous-intensity of physical activity of >=150 min/week, whereas 80.2% met the recommended level according to self-reported measures. Being single, higher education level, and greater self-regulation predicted objective physical activity in multivariate regression analysis. Greater self-regulation also predicted self-reported physical activity. Weight loss 1 year after surgery was not associated with self-reported or objectively measured physical activity. The findings show that despite large differences between accelerometer-based and subjective estimates of physical activity, the associations of self-regulatory factors and weight loss with postoperative physical activity did not vary depending on mode of measurement.