Effect of sleeve gastrectomy on postprandial lipoprotein metabolism in morbidly obese patients

Background: Obesity is associated with abnormal fasting and
postprandial lipids, which may link obesity with atherosclerosis.
We explored fasting and postprandial lipids in morbidly obese
patients treated with sleeve gastrectomy and in control subjects.
Methods: After fasting for 12 h 15 morbidly obese patients (BMI
51.4 +/- 6.5 kg/m(2), 43.7 +/- 12.6 years) received a standardized
oral fat load before and 3 months after bariatric surgery (sleeve
gastrectomy). Controls (n=9, BMI 23.1 +/- 1.4 kg/m(2)) were studied
once. Plasma was obtained fasting and then postprandially every 2 h
for 8 h. Triglycerides (TG), chylomicron-TG (CM-TG),
VLDL/chylomicron-remnant (VLDL/CR)-TG, cholesterol,
LDL-cholesterol, VLDL/CR-cholesterol and HDL-cholesterol were
isolated by ultracentrifugation at each time point. Postprandial
values were expressed as area under the curve (AUC) and incremental
area under the curve (iAUC). In addition, fasting glucose and
insulin values and HOMA-IR-Index was measured (n=14). Results:
Compared to controls morbidly obese patients had elevated TG and
slightly altered postprandial lipids. Following surgery (weight
loss 23.4 kg +/- 6.2 kg; 150 mg/dl) a similar pattern was
observed. Fasting insulin and HOMA were reduced significantly
(-51.9%; p=0.004 and -47.9%; p=0.011). Conclusions: Three months
after sleeve gastrectomy fasting and postprandial lipoprotein
metabolism and glucose metabolism is improved in morbidly obese
patients. The potential mechanisms may relate to decreased caloric
intake but also to hormonal changes.