title: Prevalence of double pre-beta lipoproteinemia in hyperlipidemic patients is influenced by gender, menopausal status, and ApoE phenotype.
abstract: Double pre-beta lipoproteinemia (DPBL) is a plasma lipoprotein phenotype characterized by the presence of two agarose gel electrophoretic populations of very low density lipoproteins (VLDLs, d < 1.006 g/mL), i.e., normal pre-beta-migrating VLDL and slow pre-beta VLDL. Slow pre-beta VLDL represents remnant lipoproteins derived from the hydrolysis of triglyceride (TG)-rich lipoproteins (TRLs), and thus DPBL is a characteristic of plasma remnant lipoprotein accumulation. To determine the prevalence of DPBL in our lipid clinic population, patients (n = 2501) were selected who (1) had an unambiguous VLDL electrophoretic phenotype and could be classified as having either DPBL (DPBL+), beta-migrating VLDL (beta-VLDL +), or an absence of both (DPBL/beta-VLDL-/-) and (2) had hypercholesterolemia (HC: plasma cholesterol > or = 6.2 mmol/L, n = 1017), hypertriglyceridemia (HTG: plasma TG > or = 2.3 mmol/L but < 15 mmol/L, n = 554) or combined hyperlipidemia (HC + HTG, n = 930). Patients with TG < 2.3 mmol/L and cholesterol < 5.2 mmol/L acted as control subjects (n = 343). Using a commercially available agarose gel electrophoresis system, we identified 220 hyperlipidemic patients (8.8%) with DPBL (versus < 1% of control). The prevalence of DPBL was higher in (1) male than in female patients (10.7% versus 6.7%), (2) postmenopausal than in premenopausal females (7.3% versus 4.1%), and (3) patients with HC + HTG than in those with HTG or HC alone (15.8% versus 8.3% versus 2.7%, respectively). Patients with an epsilon 2 allele had a higher prevalence of DPBL; i.e., 26.9% of apoE 3/2 and 26.2% of apoE 4/2 patients had DPBL compared with 6.5%, 6.8%, and 7.4% of apoE 3/3, 4/3, and 4/4 patients, respectively. DPBL patients consistently had increased levels of VLDL-C and (LDL + HDL)-TG and decreased levels of LDL-C, and their plasma lipid profiles were intermediate between those of beta-VLDL+ and DPBL/beta-VLDL -/- patients. These results demonstrate that male sex, postmenopausal status in women, and the presence of an apoE 3/2 or apoE 4/2 phenotype are associated with an increased incidence of DPBL in hyperlipidemic patients.
authors.affiliation: Hyperlipidemia and Atherosclerosis Research Group, Clinical Research Institute of Montreal, Quebec, Canada.
authors.forename: J S
authors.initials: JS
authors.lastname: Cohn
authors.forename: L M
authors.initials: LM
authors.lastname: Giroux
authors.forename: L J
authors.initials: LJ
authors.lastname: Fortin
authors.forename: J
authors.initials: J
authors.lastname: Davignon
mesh_terms: D000328:Adult; D000368:Aged; D001057:Apolipoproteins E / Q000235:genetics*; D001797:Blood Protein Electrophoresis; D005260:Female; D006801:Humans; D006951:Hyperlipoproteinemias / Q000097:blood* / Q000453:epidemiology / Q000235:genetics; D008079:Lipoproteins, VLDL / Q000097:blood*; D008297:Male; D008593:Menopause / Q000097:blood; D008875:Middle Aged; D010641:Phenotype; D015995:Prevalence; D012189:Retrospective Studies; D012727:Sex Characteristics; D014280:Triglycerides / Q000097:blood
chemical_list: D001057:Apolipoproteins E; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C030106:very low density lipoprotein triglyceride