The association of the rs670 variant of APOA1 gene with insulin resistance and lipid profile in morbid obese patients after a biliopancreatic diversion surgery.

OBJECTIVE: A common G-to-A transition (rs670) of the Apoprotein subtype 1 APOA1 gene has been evaluated. The presence of the A allele has been related with increased activity. We investigated the role of this genetic variant (rs670) on lipoprotein levels and anthropometric parameters after biliopancreatic diversion (BPD) surgery in morbid obese patients.

PATIENTS AND METHODS: Sixty-three patients with morbid obesity without diabetes mellitus type 2 were enrolled. Biochemical and anthropometric evaluation were registered before and after one, two and three years follow-up.

RESULTS: Genotype distribution was 73% (n=46) GG, 25.6% (n=16) GA and 1.4% (n=1) AA for the rs670 polymorphism. Percent excess weight loss, anthropometric and biochemical parameters improved in both groups (GG vs. GA±AA). The decrease of fasting insulin levels at 1 years (delta: -3.7±1.4 mUI/L vs. -2.9±1.2 mUI/L; p=0.02), 2 years (delta: -4.8±0.3 mUI/L vs. -4.0±0.2 mUI/L; p=0.01) and 3 years (delta: -6.7±3.1 mUI/L vs. -3.9±2.1 mUI/L; p=0.03) was higher in A allele carriers than in non carriers. The improvement of HOMA-IR levels at 1 years (delta: -3.7±1.4 mUI/L vs. -2.9±1.2 mUI/L; p=0.02), 2 years (delta: -4.8±0.3 mUI/L vs. -4.0±0.2 mUI/L; p=0.01) and 3 years (delta: -6.7±3.1 mUI/L vs. -3.9±2.1 mUI/L; p=0.03) was also higher in A allele carriers than non-carriers. Finally, the increase of HDL-cholesterol levels at 1 years (delta: 2.2±0.6 mg/dl vs. -1.2±0.2 mg/dl; p=0.001), 2 years (delta: 2.5±0.4 mg/dl vs. 0.3±0.1 mg/dl; p=0.01) and 3 years (delta: 2.4±0.6 mg/dl vs. 0.4±2.3 mg/dl; p=0.02) was higher in A allele carriers than non-carriers.

CONCLUSIONS: This variant of the APOA1 gene showed important effects on HDL-cholesterol, HOMA-IR and insulin resistance after DBP for 3 years.