Date of Completion


Embargo Period



Helen Swede, PhD; Pavlos Papasavas, MD; Valerie Duffy, PhD; Stacey Brown, PhD

Field of Study

Public Health


Master of Public Health

Open Access

Open Access


Background: Improving weight loss after bariatric surgery remains a clinical concern. An unstudied factor is the role of leptin, the appetite control hormone, as a pre-surgical predictor of weight loss. High serum levels, often seen in obesity, are an indicator of leptin resistance as the brain no longer responds to satiety signaling.

Methods: Leptin levels were ascertained in female bariatric patients (n=28) prior to surgery at a large tertiary care hospital. We calculated Pearson Correlation Coefficients (r) and unstandardized β coefficients using multivariate linear regression. Primary outcome: Percent Excess Weight Loss (%EWL) evaluated at 6- and 12-months post-surgery. Independent variables were: baseline leptin and, potential confounders, Healthy Eating Behavioral Index (HEBI) and age.

Results: Pearson correlation coefficients showed inverse associations baseline leptin with %EWL at 6-months (r=-.45, p,05). In Linear Regression, baseline leptin was inversely associated with %EWL at 6-months (adjusted β=-.12, p=.03) but the relationship was attenuated at 12-months (adjusted β=-.07. p=.47). HEBI was positively associated with %EWL at both 6-months (adjusted β=.19, p=.04) and 12-months (adjusted β=.26, p=.07).

Conclusion and Discussion: Findings suggest that higher baseline leptin might impede weight loss in the first 6 months after surgery possibly due to reduced appetite control, which held when controlling for age and healthy eating. The effect at 6-months (adjusted β = -.12) denotes that a 75 ng/mL increase in leptin might incur about 10 percentage points less EWL. Longitudinal investigations in larger studies containing an array of potential explanatory variables are recommended.

Major Advisor

Helen Swede, PhD