S16 Surgical Forum Abstracts J Am Coll Surg

and lipoprotein(a). Among surgery types, percent improvementsand dichotomous variables were compared by one-way ANOVA

and chi squared analysis respectively. Biochemical risk factorswere correlated with excess weight loss. STATA software wasused for all analysis.

RESULTS: At twelve months, the follow up rate was 77%. There

were significant demographic differences between surgery types.Those undergoing gastric bypass were younger, of higher BMI,and had greater comorbidities. A majority of risk factors variedsignificantly among surgery types. Notably, differences in fasting

insulin were observed among surgery types, with 67.0% improve-ment for gastric bypass, 32.6% for band, and 63.7% for sleeve.C-reactive protein showed 67.1% improvement for gastric bypass,

21.2% for band, and 26.3% for sleeve. The ratio of triglycerides toHDL, a predictor of heart disease, was differentially improvedamong surgery types: 38.5% in gastric bypass, 20.6% in band,

and 35.2% in sleeve.

CONCLUSIONS: All bariatric procedures demonstrated consider-able post-op reductions in weight and overall cardiovascular risk.However, gastric bypass showed significantly more improvement

in every studied cardiovascular risk factor and reduction in BMI12 months after surgery.

Rules based medicine evaluates changes in inflammationafter bariatric surgeryJohn M Morton, MD, MPH, Natalia Leva, BS, Nayna Lodhia, BSStanford University, Stanford, CA

INTRODUCTION: Several studies have demonstrated that obesityis associated with an increase in chronic low-grade inflammation

in adipose tissue. Recent technological advances allow for simulta-neous measurement of hundreds of proteins, which provide insightinto the biological activity associated with obesity and weight loss.Our study utilizes such technology to examine the protean effects

of obesity on post-surgical outcomes and comorbidities.

METHODS: Demographic, preoperative and 12-month postoper-ative data were collected on 16 individuals at a single academicinstitution. Patients were compared on the basis of BMI, percent

excess weight loss (%EWL), biochemical cardiac risk factors(BCRFs), and multiplex immunoassays that measure proteinsrelated to immune response and inflammation, metabolism, cancer,

and cell regulation.

RESULTS: 16 patients had submitted preoperative and 12-monthsamples. Patients were female, with an average age of 37.1 and BMI45.7. Significant decreases were seen in inflammatory markers andcancer markers (all p’s<0.05). Significant improvement was seen in

metabolic efficiency as represented by decreased proinsulin andc-peptide and increased levels of insulin-like growth factor binding

protein 2 (all p’s<0.05). Improvements were also observed in cellregulatory factors (all p’s<0.05).

CONCLUSIONS: After bariatric surgery, patients show significantdecreases in inflammation and improvements in metabolic func-tion. This study elucidates the positive impact of bariatric surgery

on the chronic inflammatory state and metabolic dysregulation thatunderlie obesity. Rules based medicine analysis of patient responseto bariatric surgery creates a framework for understanding changes

in phenotypes of obese patients after significant weight loss and cantarget patients who can benefit the most from surgery.

Roux-en-Y gastric bypass is correlated with decrease inadipose senescence and inflammationYong Yean Kim, MD, PhD, Nathan Liu, MD,Daniel B Leslie, MD, FACS, Sayeed Ikramuddin, MD, FACSUniversity of Minnesota, Minneapolis, MN

INTRODUCTION: Adipose tissue senescence increases withincreasing weight and also with diabetes status. Senescence is linked

to adipose tissue inflammation which is the driver of insulin resis-tance. Roux-en-Y Gastric Bypass (RYGB) is associated withimprovement in insulin resistance after surgery. We looked to seeif improvement in adipose inflammation was correlated with

decrease in senescence.

METHODS: Subcutaneous adipose tissue biopsy was performed attime of laparoscopic RYGB surgery and 7-10 days after surgery(n¼3). As surgical control, laparoscopic gastric banding(LB) was

used (n¼3). Fat was formalin fixed and paraffin embedded. Immuno-fluorescence was performed against gamma-H2AX. Random highpower field imageswere taken andpercent positive nuclei determined.

ELISA was performed on adipose tissue samples by separating thecells using a strainer andwashing the tissue with PBS.Cells and debriswas discarded and washing used for ELISA using fluorescent beads

against IL-2 and IL-6.

RESULTS: Senescence marker gamma-H2AX positive cells wasnot significantly different between RYGB (2.5%) and LB (2.2%)preoperatively. After surgery, gamma-H2AX decreased from

2.5% to 0.3% in the RYGB (p¼0.011) while not significantlydifferent in LB (2.2% to 3.6%). Then we determined the levelsof secreted cytokines, IL-2 and IL-6, in adipose tissue. IL-6 wasunchanged after surgery, however, mean fluorescence intensity

(MFI) of IL-2 decreased from 2.21 to 1.60 in the RYGB(p¼0.014) while LB was unchanged.

CONCLUSIONS: When looking at a senescence markers, gamma-H2AX, there was a decrease in senescence following RYGB but not

after LB and this was correlated with a decrease the inflammatorymarker IL-2 in RYGB. This suggests a possible association betweenRYGB and senescence.