Omega 3 fatty acids have long been used in the treatment of hypertriglyceridemia, as they reduce the hepatic production of VLDL, favor fatty acid oxidation and enhance VLDL clearance . They have also been shown to reduce levels of chylomicrons and their remnants, as well as the amount of apolipoprotein B48 . The reduction in the concentrations of triglycerides and VLDL triglycerides and the increase in HDL cholesterol noted in this study are thus in agreement with the literature mentioned. Concerning LDL cholesterol, treatment with omega 3 fatty acids in patients with hypertriglyceridemia or mixed hyperlipidemia is usually followed by a slight rise in LDL cholesterol . Although in our study, LDL cholesterol rose slightly, but not significantly after the omega 3 treatment, the marked reduction in the triglyceride/HDL cholesterol ratio noted suggests the transformation of sdLDL to larger particles .
Evidence exists for the beneficial effect on non-HDL cholesterol of the addition of omega 3 fatty acids to the treatment in persons with residual hypertriglyceridemia despite the use of statins . However, their benefit on the intestinal atherogenic lipoprotein particles has not been assessed.
The quantification of apolipoprotein B48 by ELISA is a simple way to measure postprandial metabolism, without the need for ultracentrifugation, sample delipidation and gradient electrophoresis, a very costly process. Apolipoprotein B48 is specific for the intestinal lipoproteins  and its fasting levels correlate very well with the area under the curve after a fatty meal . Its levels are raised in persons with type 2 diabetes, especially when they also have renal failure .
The effects of fluvastatin on the concentration of apolipoprotein B48 has not been reported. Nevertheless, atorvastatin is able to reduce apolipoprotein B48 concentrations by increasing the catabolism of chylomicrons and their remnants [18, 19]. This study supports the hypothesis that levels of B48-containing atherogenic lipoproteins may be further reduced by omega 3 fatty acids, even when added to the traditional statin therapy; in fact, the reduction in the B48 was over two-fold greater with the omega 3 fatty acids than with 80 mg of fluvastatin alone (Figure 1). Because we just evaluated the patients over eight weeks, the reduction in the levels of apolipoprotein B48 might be even more pronounced over time.
The apolipoprotein B48 concentrations only fell significantly after the incorporation of omega 3 fatty acids to the treatment with fluvastatin. As treatment with omega 3 fatty acids in patients with hypercholesterolemia who are receiving statins is accompanied by a reduction in ischemic events and vascular death, even in populations that have a high consumption of fish , we may speculate that the reduction in apolipoprotein B48-containing particles might contribute to this benefit. It is believed that omega 3 fatty acids enhances chylomicron clearence due to a reduction in hepatic VLDL synthesis . Moreover, in experimental models omega 3 fatty acids may also reduce intestinal lipoprotein production , which is increased in patients with insulin-resistance  and type 2 diabetes .
In conclusion, these preliminary findings suggest that treatment with 4 g of omega 3 fatty acids added to higher doses of fluvastatin in diabetic patients with mixed hyperlipidemia is accompanied by a significant additional benefit in apolipoprotein B48-containing particles and may thus represent a complementary therapy for the reduction of LDL cholesterol, non-HDL cholesterol and B100 to that achieved with statins alone. Nevertheless, due to small sample size, lack of postprandial data and open-label design, large-scale, double-blind, randomized studies are needed to confirm our results.