SHORT-TERM RESPONSE TO DIETARY COUNSELING OF HYPERLIPIDEMIC OUTPATIENTS OF A LIPID CLINIC

Objective To evaluate the efficacy of a limited dietary intervention d elivered by dietitians in a single counseling session on plasma lipid levels in free-living subjects with hyperlipidemia. Design A 2-month, nonrandomized comparative study of dietary counseling efficacy in subj ects with hyperlipidemia. Dietary instruction was conducted in a lipid clinic by dietitians. Subjects were instructed to follow a diet low i n saturated fat and cholesterol (National Education Cholesterol Progra m step 1 or 2 diets) for 2 months with concomitant energy restriction for weight reduction when necessary. Another group of patients who did not receive dietary counseling during the same period served as a con trol. Subjects Ambulatory patients were recruited from the Lipid Clini c of the Montreal Clinical Research Institute. Intervention Dietary co unseling was provided to 104 subjects with hypercholesterolemia and 11 3 subjects with hypertriglyceridemia. They were compared with 72 subje cts with hypercholesterolemia and 80 subjects with hypertriglyceridemi a who did not receive dietary counseling. Results In the hypercholeste rolemic group, significant reductions in plasma cholesterol (mean +/- standard deviation = -5.7 +/- 11.7%) and low-density lipoprotein chole sterol (LDL-C) (-7.3 +/- 14.2%) and no changes in plasma very-low-dens ity lipoprotein cholesterol (VLDL-C) or high-density lipoprotein chole sterol (HDL-C) were observed after dietary counseling. The LDL-C respo nse to diet was normally distributed, and 20% of the individuals with hypercholesterolemia reached LDL-C levels below 4.1 mmol/L. In patient s with hypercholesterolemia and no clinical evidence of familial hyper cholesterolemia, (n=76) the reductions in plasma cholesterol (-6.6 +/- 10.8%) and LDL-C (-8.2 +/- 14%) were more pronounced. Among the latte r patients, 27.6% reached LDL-C levels below 4.1 mmol/L. In subjects w ith hypertriglyceridemia, the reductions in plasma cholesterol (-4.8 /- 12.8%), triglycerides (-20.7 +/- 33%), and VLDL-C (-19.5 +/- 29%) w ere associated with an increase in LDL-C (+ 8.5 +/- 25.7%) and HDL-C ( +5.5 +/- 18%). Of the subjects with hypertriglyceridemia, 20% had trig lyceride levels below 2.3 mmol/L after treatment. No significant chang es were observed in the control groups during the same period. Conclus ions Dietary counseling of subjects with hypercholesterolemia or hyper triglyceridemia was associated with beneficial changes in plasma lipid levels after 2 months of dietary intervention. However, longer and mo re controlled the interventions are necessary for most patients to ach ieve lipid goals.