Protease inhibitor related type III hyperlipoproteinaemia is common and not associated with apolipoprotein-E E2/E2 phenotype

Objective: To determine the prevalence of type III hyperlipoproteinaemia in a cohort of HIV infected patients taking protease inhibitors and its correlation with the apolipoprotein-E2 isoform. Design: Cross sectional study of 57 consecutive HIV infected subjects taking protease inhibitor therapy for a median of 12.5 (1–29) months, seen in an outpatient HIV clinic. Controls were 17 patients on non-nucleoside reverse transcriptor inhibitor therapy (NNRTI) for 9 (1–19) months and 50 antiviral naive patients. Methods: Fasting cholesterol, triglyceride, HDL cholesterol, lipoprotein (a), and glucose were measured. Lipoprotein electrophoresis was performed on patients with a cholesterol >6.5 mmol/l and a triglyceride concentration of >4.5 mmol/l. Apolipoprotein-E phenotype was determined in serum. Results: Dyslipidaemia was found in 43 (75%) PI treated patients—37 with triglyceride >2.3 mmol/l, 30 with cholesterol >6.5 mmol/l, and nine with HDL cholesterol 300 mg/l. 11 patients (19.3%) had a type III hyperlipoproteinaemia pattern. Only one was homozygous for the E2 phenotype and none had clinical diabetes. An additional patient had a serum lipid profile compatible with type III hyperlipoproteinaemia and an E3/E2 phenotype in whom electrophoresis was not carried out before treatment. Six (35%) of the NNRTI and 16 (32%) of the antiviral naive patients had dyslipidaemia. 18 (31.6%) of the PI and none of the control patients had a cholesterol and/or triglyceride >8 mmol/l. Conclusion: Type III hyperlipoproteinaemia is common in this group of patients and need not be associated with the apolipoprotein-E2/E2 isoform. HIV protease inhibitors may interfere with lipoprotein receptor related protein. Key Words: HIV; protease inhibitors; hyperlipidaemia; apolipoprotein-E