Weight loss after gastric bypass improves lipid profile
MedWire News: Weight loss after laparoscopic Roux-en-Y gastric bypass (LRYGBP) surgery improves patients' lipid profiles and reduces insulin resistance, study findings show.
And the association between LRYGBP and lipid profile improvement is stronger in men than women, report Ignacio Garcia-Marirrodriga (Centro Médico Teknon, Barcelona, Spain) and co-authors in the journal Obesity Surgery.
They reviewed the medical charts of 114 consecutive patients who underwent LRYGBP between January 2007 and December 2009.
The fasting lipids subfractions, including total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, and triglycerides, as well as homeostasis model assessment for insulin resistance index (HOMA-IR) in each patient were assessed pre-operatively and at 6, 12, and 18 month follow-ups after surgery.
The findings showed that excess weight loss at 6, 12, and 18 months was -49.3%, -67.6%, and -70.0%, respectively.
Total cholesterol was reduced 23.6%, 22.3%, and 18.4% at 6, 12, and 18 months, respectively. Similarly, LDL-cholesterol also declined, by 24.1%, 29.8%, and 26.7%, respectively.
In contrast, HDL-cholesterol was reduced by 13.0% at 6 months but was increased by 3.8% at 12 months and by 19.3% at 18 months.
Triglyceride levels were reduced by 27.4%, 37.8%, and 47.3%, at 6, 12, and 18 month follow-ups, respectively.
Further analysis revealed that body mass index (BMI) was significantly and positively associated with total cholesterol, LDL cholesterol, and triglycerides, as well as with the total cholesterol/HDL-cholesterol and triglyceride/HDL-cholesterol ratios. In contrast, HDL-cholesterol concentration was inversely associated with BMI.
In a similar fashion, while excess weight loss was significantly and positively associated with total cholesterol, LDL-cholesterol, triglycerides and the triglyceride/HDL-cholesterol ratio, it was significantly and inversely associated with HDL-cholesterol.
In addition, robust significant correlations were observed between BMI, HOMA-IR and insulin concentrations.
The researchers note that the lipid profile of the male participants showed a more robust correlation with excess weight loss than that of female participants.
They point out that the limitations of their study include its retrospective nature and relatively small sample size.
Commenting on future directions, Garcia-Marirrodriga and team write: "We aim at comparing the lipid profiles of conservatively treated morbidly obese patients (diet alone) versus those undergoing isolated restrictive procedures versus mixed procedures."
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By Piriya Mahendra