Study Roundup

Published in May Issue             

Site-Specific Approach to Reducing Emergency Department Visits Following Surgery
(Annals of Surgery)

To explore the efficacy of current bariatric perioperative measures in reducing emergency department (ED) visits following surgery, data from 48,035 eligible bariatric surgery patients across 37 Michigan Bariatric Surgical Collaborative (MBSC) sites was collected between January 2012 and October 2015. Hospitals were ranked according to their risk- and reliability-adjusted ED visit rates. Only three of the 30 surgery, hospital, and patient summary characteristics studied were significant predictors of a hospital's ED visit rate: rate of sleeve gastrectomies, rate of readmissions, and rate of venous thromboembolism complications. A hospital's compliance with the perioperative measures evaluated was not a significant predictor of ED visit rates. The findings suggest current practices aimed at reducing ED visits appear to be ineffective and a more tailored approach to ED visit reduction may be more successful.

Changes in Prescription Drug Use After Gastric Bypass Surgery: A Nationwide Cohort Study
(Annals of Surgery)

A nationwide population-based cohort study evaluated changes over time in drug use among patients undergoing RYGB versus a match comparison cohort. Prevalence ratios for 9,908 patients undergoing RYGB in Denmark from 2006 to 2010 were compared for prescription drug use 36 months after RYGB to use 6 months before surgery. This data was also compared to prevelance ratios for 99,080 matched general population members. At baseline, more RYGB patients used a prescription drug compared to the general population (81.5% vs 49.1%, respectively). After 3 years, the use had decreased slightly among RYGB patients (PR = 0.93), but increased in the comparison cohort (PR = 1.05). In the RYGB cohort, large, sustained decreases occurred for drug treatment of metabolic syndrome-related conditions, including any glucose-lowering medications (PR = 0.28) and lipid-modifying medications (PR = 0.50). Use of inhalants for obstructive airway diseases also decreased (PR = 0.79). Use of neuropsychiatric drugs was two-fold higher at baseline in the RYGB cohort (22.8% vs 10.9%) and increased further after surgery — antidepressants (PR = 1.13), antipsychotics (PR = 1.39), and potential treatment of neuropathy (PR = 1.39).

Risk of Abdominal Surgery in Pregnancy Among Women Who Have Undergone
Bariatric Surgery
(Obstetrics & Gynecology)

A national cohort study, merging data from the Swedish Medical Birth Registry and the Swedish National Patient Registry, compared rates of abdominal surgery during pregnancy among women with previous bariatric surgery and women with a first-trimester BMI greater than 35 and no previous bariatric surgery. During the first pregnancy after bariatric surgery, the rate of surgery for intestinal obstruction was 1.5% (39/2,543) in women in the surgery group compared with 0.02% (4/21,909) among women in the control group. Similarly, the rate of diagnostic laparoscopy or laparotomy was 1.5% (37/2,542) among women in the surgery group compared with 0.1% (18/21,909) among women in the control group. The data demonstrates that bariatric surgery is associated with an increased risk of abdominal surgery during pregnancy.

Cost-Effectiveness of Gastric Band Surgery for Overweight but Not Obese Adults with Type 2 Diabetes in the U.S. (Journal of Diabetes and Its Complications)

A microsimulation model was used to determine the cost-effectiveness of gastric band surgery (GB) in overweight patients who receive standard diabetes care. The incremental cost-effectiveness ratio for GB at two years exceeded $90,000 per quality-adjusted life year gained but decreased to $52,000, $29,000 and $22,000 when the health benefits of surgery were assumed to endure for 5, 10 and 15 years, respectively. The cost-effectiveness of GB was sensitive to utility gained from weight loss and, to a lesser degree, the costs of surgery. However, the cost-effectiveness of GB surgery was minimaly effected by improvements in HbA1c, systolic blood pressure and cholesterol. The findings suggest GB for overweight but not obese people with T2D appears to be cost-effective if weight loss endures for more than five years.

Cost of Bariatric Surgery and Factors Associated with Increased Cost: An Analysis of National Inpatient Sample (SOARD)

A retrospective analysis of 2012-2013 Healthcare Cost and Utilization Project - Nationwide Inpatient Sample was conducted to evaluate the national cost of bariatric surgery and identify factors associated with higher costs. A total of 45,219 patients with morbid obesity who had undergone RYGB, sleeve gastrectomy (SG), or adjustable gastric banding (GB) were included (RYGB=20,966, SG=22,380, and AGB=1,873). “Hospital charges” were converted to “cost” using hospital specific cost-to-charge ratio. The median calculated cost for RYGB, SG, and GB was $12,543 ($9,970-$15,857), $10,531 ($8,248-$13,527), and $9,219 ($7,545-$12106), respectively. Robotic-assisted procedures had the highest impact on the cost. Hospital cost of RYGB and SG increased linearly with the length of hospital stay and almost doubled
after 7 days.

30 Day Readmission Following Weight Loss Surgery: Can Psychological Factors Predict Non-Specific Indications for Readmission (SOARD)

Researchers investigated whether pre-surgical psychosocial factors are related to readmission following bariatric surgery. Data was analylzed from 102 patients readmitted within 30 days between the time period 2012 to 2015. Psychiatric variables and psychological testing at intake were compared to a second patient cohort of 204 non-readmitted matched patients. Those with specific complications (n=61) were delineated from those with non-specific indications (n=33). Those with non-specific readmissions were younger and more likely to be female. These patients were also less likely to be in outpatient psychiatric care than non-readmitted patients. Significant differences were found on the Uncommon Virtues scale of the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF), that reflected a tendency to under report disinhibited behaviors. Those with non-specific readmissions had significantly higher under reporting scores compared to those with specific indications or those not readmitted. The tendency to under report may impact the care team’s ability to identify risk factors that could be ameliorated prior to surgery. Readmitted patients were also less likely to be receiving mental health care.

Surgery-Related Gastrointestinal Symptoms in a Prospective Study of Bariatric Surgery Patients: 3-Year Follow-up (SOARD)

A substudy of the Longitudinal Assessment of Bariatric Surgery Consortium reported on surgery-related gastrointestinal (GI) symptoms over the first 3 years following RYGB and laparoscopic adjustable gastric band (LAGB). Three academic medical centers in the U.S. identified 183 participants (pre-surgery median BMI was 45.1) that completed the Eating Disorder Examination-Bariatric Surgery Version interview at >= one annual assessment. Patients self-reported frequency of dysphagia, dumping syndrome and spontaneous vomiting. Prevalence of dysphagia >=weekly decreased post-LAGB from 43.9% in year 1 to 27.5% in year 3. Dysphagia and dumping >=weekly also appeared to decrease in years 1-3 post-RYGB from 16.7% to 10.9% and from 9.9% to 6.3%, respectively. Vomiting >=weekly was rare (< 6%) in years 1-3 following both procedures. Loss of control eating >=weekly was associated with higher risk of >=weekly dysphagia. The prevalence of bariatric surgery-related GI symptoms appear to decrease across follow-up, and symptoms were associated with loss of control eating, suggesting a target for clinical intervention.

Laparoscopic Sleeve Gastrectomy in Kidney Transplant Candidates: a Case Series
(Obesity Surgery)

To evaluate the feasibility and the results of SG for patients with obesity awaiting a kidney transplant, retrospective data was collected on nine patients with dialysis-dependent renal failure (DDFR) that had undergone sleeve gastrectomy. All patients were contraindicated for kidney transplantation due to the presence of morbid obesity. At the start, mean BMI was 45.9 and all patients presented with hypertension and sleep apnea, and six out nine were diabetics. In the immediate postoperative period, all patients were transferred to the intensive care unit for a mean stay of 2.1 days. The mean hospital stay was 5.5 days. The total weight loss was 27.1, 33.6, and 39.5 kg at 6, 12, and 18 months, respectively. One patient underwent renal transplantation 18 months after SG and the other five patients were actively listed for kidney transplantation, suggesting SG is an effective and safe procedure in DDRF patients with concomitant obesity and can increase access to transplantation.