Impaired postprandial
lipoprotein metabolism has been found to be related to the extent of
coronary artery disease. Moreover, since
dyslipoproteinemias are associated with impaired hemorrheology, we investigated the effect of postprandial
hypertriglyceridemia on hemorrheological parameters before and after
triglyceride-lowering
therapy.
Triglyceride-rich
lipoproteins (TRLs) separated by ultracentrifugation (d < 1.006 g/dL) and
chylomicrons and
chylomicron remnants (quantified by
apolipoprotein [
apo] B-48 determination) were determined after a fat load in 10 patients with
familial hypertriglyceridemia before and after
therapy with
gemfibrozil (900 mg daily).
Lipid and hemorrheological parameters (plasma and whole-blood viscosity [PV and BV], red cell aggregation [RCA], hematocrit, and
fibrinogen) were determined at baseline and every hour up to 6 hours postprandially. Fasting total
triglycerides and TRL
triglycerides significantly decreased with
gemfibrozil therapy (P < .01). Total
triglycerides postprandially increased from 9.53 +/- 1.72 to 14.47 +/- 2.07 mmol/L (TRL
triglycerides by 61%) before
therapy (P < .05) and from 4.61 +/- 1.28 to 7.17 +/- 0.99 mmol/L (TRL
triglycerides by 57%) after
therapy (P < .05). The postprandial TRL
apo B increase was reduced with
gemfibrozil (from 11.6 +/- 2.8 to 20.7 +/- 5.0 mg/dL with
therapy v 19.0 +/- 7.6 to 33.0 +/- 12.5 mg/dL before
therapy, P < .05, respectively) with a proportionally greater increase in
apo B-48 (119% and 169%, respectively) compared with
apo B-100 (64% and 64%, respectively). Fasting RCA was improved with
lipid-lowering
therapy (P < .05), but PV, BV, RCA, and
fibrinogen did not show any statistically significant postprandial changes either before or after
lipid-lowering
therapy. In summary, we did not find any statistically significant changes in hemorrheological parameters, despite a strong postprandial increase of
triglycerides. In particular, these findings were independent of fasting
triglyceride levels. We conclude that
triglyceride-lowering
therapy by
gemfibrozil had no substantial beneficial effects with respect to hemorrheology in patients with
familial hypertriglyceridemia.