The effect of dietary intervention on serum lipid levels in type 2 diabetes mellitus

Dietary therapy is the cornerstone of lipid management in patients with type 2 diabetes mellitus. The key strategies are the reduction of intake of saturated fat, trans unsaturated fat and cholesterol, and the reduction of energy intake to promote weight loss. This approach will produce significant improvements in the serum levels of low-density lipoprotein (LDL) cholesterol, triglycerides, and high-density lipoprotein (HDL) cholesterol. According to both the American Diabetes Association and the National Cholesterol Education Program (NCEP), the primary target of therapy is the serum LDL cholesterol level, with the secondary targets being non-HDL cholesterol, triglycerides, and HDL cholesterol. The recently updated guidelines of the NCEP place new emphasis on increasing soluble fiber intake to 10 to 25 g/d and adding foods fortified with plant stanols/sterols (2 g/d) as options to enhance the LDL cholesterol-lowering effect of diet.     

Lipoprotein distribution and composition in the human nephrotic syndrome

Plasma lipoprotein profiles were quantitated in 9 patients with the nephrotic syndrome. Six subjects were studied both during an active proteinuric phase and during a remission phase without proteinuria. During the proteinuric phase, the plasma triglyceride, cholesterol and apo B levels were markedly increased, whereas the HDL cholesterol, apo A-I, and apo A-II concentrations were normal. Analysis of the distribution and composition of the lipoprotein subclasses, separated by isopycnic ultracentrifugation, showed typical patterns characterized by: (1) elevated apo B-rich VLDL and LDL fractions, (2) the presence of a denser LDL subfraction, floating at d 1.053 g/ml, which contained about 35% of LDL cholesterol and apo B and (3) a redistribution among HDL subclasses. The HDL2b (d 1.063-1.100 g/ml) fraction was markedly decreased, while the HDL2a + 3a (d 1.100-1.150 g/ml) and HDL3b + 3c (d 1.150-1.210 g/ml) subclasses were moderately elevated. The decreased cholesterol and apo A-I contents of HDL2b therefore counterbalanced their increase in HDL2a + 3a and HDL3b + 3c, resulting in normal plasma HDL cholesterol and apo A-I concentrations. When reinvestigated during a remission phase without proteinuria, the nephrotic patient's overall lipoprotein distribution and composition were similar to those in healthy controls. The combination of several factors such as the presence of elevated apo B-rich VLDL, IDL and LDL, together with decreased HDL2 cholesterol and HDL2 apo A-I suggests that nephrotic patients are at increased risk for atherosclerosis.     

Egg consumption and high-density-lipoprotein cholesterol

Abstract. Objectives . To examine if increased egg consumption raises serum high-density-lipoprotein (HDL) cholesterol in healthy individuals. Design . A cross-over study. Setting . A private clinic for preventive health examinations in Copenhagen. Subjects . Twenty-four healthy adults, 12 men and 12 women, aged 23–52 (median 40) years. Interventions . After a 1-week control period each person added two bolled eggs to the usual daily diet for 6 weeks. All persons were instructed not to change the lifestyle in other ways during the whole study period. Main outcome measures . Serum HDL cholesterol, total cholesterol and triglycerides were measured before, during and after 6 weeks of extra egg consumption. The corresponding serum Iow-density-lipoprotein (LDL) cholesterol was calculated from the Friedewald formula. Results . After 6 weeks of extra egg consumption serum HDL cholesterol increased by 10% (P < 0.05) and total cholesterol increased 4% (P < 0.05), whereas the ratio total cholesterol/HDL cholesterol did not change significantly. Serum triglycerides and LDL cholesterol were also unchanged. Conclusions . A moderate egg intake should not be rigorously restricted in healthy individuals.     

Serum lipid and lipoprotein fractions in bengal gram and biochanin A induced alterations in atherosclerosis.

Serum lipids and lipoproteins were studied in rabbits fed on egg yolk supplemented diet to induce hypercholesterolemia. Bengal gram and synthetically pure isoflavone Biochanin A have been used as lipodiatic agents in this study. Rabbits were divided into four groups: Group A were fed on egg yolk supplement alone to form the positive control group, Group B were fed with 40 gms of overnight soaked bengal gram (Cicer arietinum), Group C were fed with 50 mgs of Biochanin A fortnightly, Group D was negative control group fed on pelleted laboratory feed. Serum samples were taken every month and total cholesterol, triglycerides and HDL cholesterol were estimated. The other lipoproteins like LDL cholesterol and VLDL cholesterol were obtained by calculations. The Group B and C showed a significant decrease of their lipids and lipoprotein in comparison to Group A thereby indicating the lipodiatic effect of these two substances. However, HDL cholesterol showed an increase in these two groups thereby proving that an increased HDL cholesterol has a protective effect on the atherosclerotic process.     

Effect of exercise training and diet modification on serum lipids and lipoproteins in coronary artery disease patients treated with thiazides

The effects of chronic exercise training and diet modification on serum lipids and lipoproteins were measured in 17 hypertensive males and 41 normotensive males with documented coronary artery disease (CAD). Exercise consisted of aerobic activities which were performed at approximately 75-85% of the symptom-limited maximum heart rate for 30-40 minutes, three times weekly for 3 months. Each participant's diet was also controlled, the recommended daily intake of fat and cholesterol was no more than 40 g/day and 200 mg/day, respectively. Significant increases in estimated VO2max and total cholesterol/high density lipoprotein (HDL) and a significant decrease in serum triglycerides were documented after training. Significant differences in serum cholesterol and triglycerides between the nondiuretic and diuretic patients were also noted. No significant changes were found in low density lipoprotein (LDL), HDL, or body weight. Vigorous aerobic training and diet modification can favorably modify the deleterious effects of diuretic medications on serum triglycerides and total cholesterol/HDL in patients with documented CAD.     

Cholesterol lowering with high-viscosity hydroxypropylmethylcellulose

Hydroxypropylmethylcellulose (HPMC) is a food gum having several structural and functional properties in common with hypocholesterolemic soluble fibers. The safety and cholestero-lowering efficacy of HPMC, incorporated into a National Cholesterol Education Program Step I diet, was compared with placebo in patients with mild to moderate hypercholesterolemia. After an 8-week National Cholesterol Education Program Step I dietary lead-in phase, 160 patients with low-density lipoprotein (LDL) cholesterol between 130 and 200 mg/dl and triglycerides <300 mg/dl were randomized to placebo, 2.5, 5.0, or 7.5 g/day of HPMC for a 6-week treatment period. Patients returned to the clinic every 2 weeks for lipid measurements and safety assessments. HPMC significantly lowered total, LDL, and non-high-density lipoprotein (HDL) cholesterol. LDL cholesterol concentrations (average of weeks 4 and 6) decreased by 3.0% (4.9 mg/dl), 5.9% (10.3 mg/dl), 12.1% (20.4 mg/dl), and 11.7% (20.3 mg/dl) from baseline levels in the placebo and 2.5, 5.0, and 7.5 g/day HPMC treatment groups, respectively. Statistically significant (p<0.05) reductions in LDL cholesterol were observed in the 5.0 and 7.5 g/day HPMC groups compared with placebo and 2.5 g/day HPMC treatment groups. Total and non-HDL cholesterol responses paralleled those of LDL cholesterol. There were no significant differences between the treatment groups in HDL cholesterol or triglyceride responses, incidence of adverse experiences, or gastrointestinal-related adverse experiences. These results suggest that HPMC is a well-tolerated and effective adjunct to diet for lowering LDL cholesterol in patients with mild to moderate hypercholesterolemia.     

Effect of colestipol and clofibrate on plasma lipid and lipoproteins in Type IIa hyperlipoproteinemia

The effects of 2.0 g of clofibrate and 15, 20 and 30 g of colestipol on plasma lipid and lipoprotein levels were evaluated in adult patients with Type IIa hyperlipoproteinemia. Clofibrate treatment was associated with decreases of 11.0% in plasma cholesterol, 15.2% in LDL cholesterol, 26.1% in triglycerides, and an 11.3% increase in HDL cholesterol. The reductions in total cholesterol with the various doses of colestipol ranged from 11.9 to 17.8% and reductions in LDL cholesterol ranged from 16.1 to 27.3%. Colestipol treatment was not associated with any significant change in HDL cholesterol levels and minor increases in triglycerides. The addition of clofibrate to patients receiving colestipol resulted in a significant increase in HDL cholesterol and a decrease in triglycerides, but no additional reduction in total or LDL cholesterol.     

Use of dietary fish oil--an alternative to drug therapy of dyslipidemia

The clinical efficacy of "Food ichthyenic oil", a new foodstuff, was studied in 129 patients with atherogenic dyslipidemia. The oil was given in a daily dose of 30 ml which contained 8 g polyunsaturated fatty acids of the omega-3 class. All the patients were divided into 3 groups: (1) 44 patients with 5.2-6.5 mmol/l cholesterol; (2) 37 with over 6.5 mmol/l, and (3) 48 with hypercholesterolemia (cholesterol over 5.2 mmol/l and hypertriglyceridemia (triglycerides over 2.3 mmol/l). Following 1-month therapy, all the groups displayed lower low density lipoprotein cholesterol levels and significantly higher high density lipoprotein cholesterol concentrations. After 4-month intake of ichthyenic oil, the levels of total and LDL cholesterol returned to the baseline values, whereas the concentration of HDL cholesterol was significantly higher than the baseline one. Following 12-month therapy, there were 15 and 14% decreases in total and LDL cholesterol, respectively, a 16% increase in HDL cholesterol. The patients from Group 3 exhibited low VLDL cholesterol and triglyceride levels.     

Lipoprotein fractions, lipoprotein lipase and hepatic triglyceride lipase during short-term and long-term uptake of ethanol in healthy subjects

In short-term experiments, healthy fasting persons were given a basic dose of 0.5 g of ethanol/kg body weight, followed by hourly maintenance doses of 0.15 g of ethanol/kg body weight. After 10 h there was a significant increase of triglycerides in the VLDL, LDL, and HDL, the main rise (from 42 to 92 mg/dl) being found in the VLDL triglycerides. Other subjects, who received nourishment isocaloric with ethanol, likewise showed a significant rise of triglycerides in all lipoprotein fractions. Chylomicron triglycerides increased from 9.3 to 35.5 mg/dl. There was no significant change in postheparin HTGL, but postheparin LPL activity decreased after 10 h from 17.9 to 12.2 mmol FFA/ml/h in the fasting subjects, and from 28.5 to 10.2 mmol/FFA/ml/h in the persons receiving food. In long-term experiments after 4 weeks of 70 - 80 g of ethanol and isocaloric food daily, triglycerides increased, especially in the VLDL (from 50 to 82 mg/dl). The increase in the HDL, however, was also significant. After 4 weeks of ethanol, the chylomicron triglycerides in the plasma of the fasting subjects reached a value of 29.3 mg/100 ml, LDL cholesterol decreased, and HDL cholesterol increased. After 4 weeks of ethanol there was an increase in the lipoprotein lipase of the adipose tissue.     

Effects of a low-fat diet on plasma lipoprotein levels

Lowering the intake of fat to decrease serum cholesterol levels has unknown effects on the proportion of cholesterol in low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Twenty normolipidemic nonvegetarians were given dietary instruction and supervision in a low-fat, semivegetarian diet for three months. Mean consumption of total fat, saturated fat, and cholesterol decreased, whereas intake of carbohydrate increased significantly on a low-fat diet. Plasma LDL levels decreased by 18% and HDL levels by 7% from prestudy baseline levels. The LDL/HDL ratio declined by 11%. Plasma triglyceride levels and body weight were unchanged. In individual subjects, the decrements in consumption of saturated fat and the increments in ingestion of polyunsaturated fat were each significantly correlated with decreases in LDL. One year after the subjects had returned to a self-selected diet, levels of dietary saturated fat and cholesterol and the plasma LDL/HDL ratio remained significantly below prestudy levels. This study and others suggest that a low-fat, high-carbohydrate diet favorably affects the plasma LDL/HDL proportion by decreasing LDL on a percentage basis 2 1/2 to three times more than it decreases HDL.     

Effects of acarbose on serum lipoproteins in healthy individuals during prolonged administration of a fiber-free formula diet

The effects of the disaccharidase inhibitor acarbose on serum lipoprotein lipid concentrations were investigated in healthy subjects during prolonged feeding of a fiber-free formula diet. Acarbose was shown to decrease cholesterol and fasting triglyceride concentrations, whereas the postprandial increment of triglycerides was not diminished. The response of fasting triglycerides to acarbose treatment appeared to be related to dietary fat intake, but not to the drug-induced reduction of postprandial glucose and insulin concentrations. Both the triglyceride and the cholesterol lowering efficacy were less pronounced with a higher amount of saturated fat than with a lower intake of fat mainly composed of polyunsaturated fatty acids. The decrease in total cholesterol was shown to be a consequence of a significant reduction in low density lipoprotein (LDL) cholesterol. Since high density lipoprotein (HDL) cholesterol concentrations remained unaltered, the ratio of HDL/LDL cholesterol changed in a beneficial way.     

Effect of dietary sodium intake on blood lipids: results from the DASH-sodium trial

We evaluated the effect on serum lipids of sodium intake in 2 diets. Participants were randomly assigned to a typical American control diet or the Dietary Approaches to Stop Hypertension (DASH) diet, each prepared with 3 levels of sodium (targeted at 50, 100, and 150 mmol/d per 2100 kcal). The DASH diet is increased in fruits, vegetables, and low-fat dairy products and is reduced in saturated and total fat. Within assigned diet, participants ate each sodium level for 30 days. The order of sodium intake was random. Participants were 390 adults, age 22 years or older, with blood pressure of 120 to 159 mm Hg systolic and 80 to 95 mm Hg diastolic. Serum lipids were measured at baseline and at the end of each sodium period. Within each diet, sodium intake did not significantly affect serum total cholesterol, LDL cholesterol, HDL cholesterol, or triglycerides. On the control diet, the ratio of total cholesterol-to-HDL cholesterol increased by 2% from 4.53 on higher sodium to 4.63 on lower sodium intake (P=0.04). On the DASH diet, sodium intake did not affect this ratio. There was no dose-response of sodium intake on serum lipids or the cholesterol ratio in either diet. At each sodium level, total cholesterol, LDL cholesterol, and HDL cholesterol were lower on the DASH diet versus the typical American diet. There were no significant interactions between the effects of sodium and the DASH diet on serum lipids. In conclusion, changes in dietary sodium intake over the range of 50 to 150 mmol/d did not affect blood lipid concentrations.     

A comparative study of the effects of acipimox and clofibrate in type III and type IV hyperlipoproteinemia

Acipimox, an analogue of nicotinic acid, is a hypolipidemic drug with antilipolytic activity. Ten patients with type III and 10 with type IV hyperlipoproteinemia participated in a comparative open cross-over study of the effect of acipimox (750 mg/day) and clofibrate (2 g/day) on lipoproteins, apoliproproteins and postheparin lipase activities during 6 weeks. During acipimox treatment 2 type III patients complained of flushing, resulting in one drop-out. In the type III patients serum cholesterol decreased 30% (P less than 0.01) during treatment with acipimox and 24% (P less than 0.01) with clofibrate, and serum triglycerides 48% (P less than 0.01) and 34% (P less than 0.01), respectively. In the type IV patients serum cholesterol remained unchanged and serum triglycerides decreased 34% (P less than 0.05) and 35% (P less than 0.01), respectively. HDL cholesterol increased during treatment with both drugs in both groups between 6 and 15% (P less than 0.05) mainly due to a rise in HDL3 cholesterol (d greater than 1.100 g/ml). LDL cholesterol increased significantly during treatment with clofibrate, but not with acipimox. There were no or slight changes in the apoproteins A and B. Postheparin lipoprotein lipase increased during clofibrate treatment and hepatic lipase decreased during acipimox treatment. We concluded that acipimox in a dose of 750 mg/day has a similar hypolipidemic effect as 2 g clofibrate daily in type III and IV hyperlipoproteinemia.     

Differential effects of continuous versus intermittent administration of growth hormone to hypophysectomized female rats on serum lipoproteins and their apoproteins

The effects of the plasma pattern of GH on serum and lipoprotein levels of total cholesterol, triglycerides, apolipoprotein A-I (apo A-I), apolipoprotein B 48/100 (apo B), and apolipoprotein E (apo E) were studied in hypophysectomized female Sprague-Dawley rats, which had been given replacement therapy with L-T4 and hydrocortisone. Bovine GH (1 mg/kg.day) was administered sc either continuously by means of osmotic minipumps or by two daily injections. Serum lipoproteins were separated by sequential ultracentrifugation into very low density lipoproteins [density (d) less than 1.006 g/ml], low density lipoproteins (LDL; d 1.006-1.063 g/ml) and high density lipoproteins (HDL; d 1.063-1.21 g/ml). The content of total cholesterol and triglycerides were then determined. Apo A-I, apo B, and apo E were isolated from rat serum and antibodies raised in rabbits. In serum and in lipoprotein fractions, the content of apo A-I, apo-B, and apo E were determined by electroimmunoassay. After hypophysectomy, there occurred a decrease in serum cholesterol and serum levels of apo A-I and apo E, in spite of replacement therapy with T4 and cortisone. Similar changes were also observed in HDL. In contrast, apo B, cholesterol, and triglycerides were increased in LDL. Estradiol treatment had no effect on these changes. Continuous infusion of GH resulted in an increase in cholesterol and apo E in serum and HDL to the levels of intact females. In contrast, GH given twice daily had no effect. Therefore, the sexually dimorphic secretion of GH may be important for the regulation of sex differences in apo E and HDL cholesterol levels. There were no consistent effects of GH treatment on the levels of apo A-I in serum or HDL, but GH treatment resulted in a decrease in apo B and triglycerides in both serum and LDL, regardless of the mode of administration. This suggests that GH regulates the serum and LDL levels of apo B and triglycerides independently of the secretory pattern.     

Comparison of Bezafibrate and Simvastatin in the Treatment of Dyslipidaemia in Patients with NIDDM

Fibrates and HMG CoA reductase inhibitors are commonly used in the treatment of diabetic dyslipidaemia. However, these two groups of drugs have not been compared in diabetic patients in a randomized controlled trial. Therefore, a multicentre study was performed in 73 subjects with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) and combined hyperlipidaemia (serum cholesterol 6.2–10.0 mmol l⁻¹, serum triglycerides 2.3–10.0 mmol l⁻¹), comparing the efficacy of 400 mg bezafibrate with 10 mg simvastatin in a double-blind fashion. Treatment with bezafibrate during 12 weeks reduced serum triglycerides significantly more than simvastatin (−41 % vs −22 %, p < 0.001) and increased HDL cholesterol more (bezafibrate: + 17 % vs simvastatin: + 9 %, p < 0.05). LDL cholesterol levels decreased by 14 % (p < 0.001) during simvastatin and increased by 21 % (p < 0.01) during bezafibrate. This increase in LDL cholesterol was positively correlated with fasting serum triglycerides (p < 0.001) and was associated with a reduction of the serum apolipoprotein B concentration, suggesting an increase in LDL particle size. Metabolic control of diabetes (fasting glycaemia; HbA_1c) and insulin secretion (C-peptide levels) were unaffected by both treatments. The incidence of side-effects during treatment was similar for both drugs. Thus, 400 mg bezafibrate mainly increases HDL cholesterol and lowers serum triglycerides but at the expense of an increase in LDL cholesterol; 10 mg simvastatin lowers LDL cholesterin more effectively but has a smaller effect on HDL cholesterol and triglycerides. © 1997 John Wiley & Sons, Ltd.     

Sequence of alcohol-induced initial changes in plasma lipoproteins (VLDL and HDL) and lipolytic enzymes in humans

The sequence of alterations in the concentration and composition of different plasma lipoproteins following alcohol intake is not known. We therefore monitored the concentrations of cholesterol, triglycerides, phospholipids, and proteins in the major lipoprotein fractions (VLDL, LDL, HDL2, and HDL3) in ten nonalcoholic healthy male volunteers who were given 5.5 g of alcohol per kilogram of body weight during 21/2 days (a weekend). In addition, lipoprotein lipase activity was measured in post-heparin plasma and in adipose tissue and hepatic lipase activity was measured in post-heparin plasma before and after the experiment. in a separate control experiment, the same subjects received meals and liquids without alcohol. Blood alcohol levels remained below 1.5 g/L. Alcohol caused a progressive increase in the fasting VLDL triglyceride and phospholipid concentrations, both of which were doubled during the experiment (P less than 0.001). In contrast, the VLDL cholesterol levels remained unchanged until the third morning, when there was a slight increase. The LDL triglyceride and phospholipid concentrations also rose without simultaneous changes in the LDL cholesterol concentration. Consistent with these changes, the HDL cholesterol concentration showed no response to alcohol during the experiment, but the HDL phospholipid level rose from 76 to 99 mg/dL (P less than 0.001). This was reflected as an increase in the HDL2 concentration from 124 to 158 mg/dL (P less than 0.01), whereas no change occurred in the HDL3 level. The increment of HDL2 concentration was due to a rise of its triglycerides, phospholipids, and apoproteins A-I and A-II but not to a rise of cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)     

Nutrient intake with low-fat diets in rehabilitation of patients with coronary heart disease

We investigated the nutritional value of a very low fat diet (diet I) adapted to nutritional habits in Germany. Data were compared to a low fat diet (diet II) according to the American Heart Association. The study was performed in 37 patients with coronary heart disease (30 males and 7 females, age 45-83 yrs) stratified to the 2 dietary treatments. Daily fat intake was 38 g (24% of energy intake of 6.5 MJ/d) in diet I and 60 g (31% of 7.3 MJ/d) in diet II (p < 0.01), respectively. When compared with diet II, in diet I the intake of cholesterol, saturated and mono-unsaturated fatty acids, Vit. A, Vit. D and Vit. B12 were all reduced (p < 0.01), whereas the uptake of Vit. C was increased p < 0.01. The intake of folic acid was low in both groups. Both diets resulted in a decrease in BMI, systolic and diastolic blood pressure, plasma cholesterol and LDL cholesterol levels. Concomitantly plasma triglycerides only decreased in response to diet I but HDL cholesterol levels remained unchanged. Reduction of BMI and cholesterol levels were dependent on baseline BMI and cholesterol concentrations, respectively. The cholesterol lowering effect of diet I is in part attributed to the weight lowering effect of the diet. Taking into account the nutritional habits in Germany, very low fat diets seem to be adequate with respect to their nutritional value. Both diets are effective in lowering body weight, plasma cholesterol and triglyceride levels without affecting HDL cholesterol. These effects are most pronounced in overweight and hypercholesterolemic patients.     

Changes in very low and low density lipoproteins with dietary fat modification

Since VLDL and LDL are involved in atherogenesis, their response to dietary modification was studied in 15 normal male prisoners. A 3-month reference diet (P/S ratio 0.3, daily cholesterol intake 370 mg) was compared with a modified fat diet (P/S 1.0, 250 mg) given for further 3 months. The decrement in serum cholesterol by 32 mg/dl reflected a decrease in VLDL and LDL. It was associated with a decrease in serum apolipoprotein B by 16 mg/dl and in serum apolipoprotein E by 1.2 mg/dl. The decrement in VLDL cholesterol was paralleled by a lowered VLDL apolipoprotein E content. Serum and VLDL triglycerides, HDL cholesterol and the serum apolipoproteins A-I and A-II did not change significantly. One beneficial result of a conventional dietary regimen is lowered LDL with unaffected HDL. Another effect is the apparent modification of VLDL with a decrement of cholesterol and apolipoprotein E-enriched particles.     

Metabolic studies with probucol in hypercholesterolaemia

Probucol (1 g/day) was administered for 6 months to 16 hypercholesterolaemic patients previously stabilized on diet alone. Total plasma cholesterol fell by 16%, LDL cholesterol by 14% and HDL cholesterol by 41%. The ratio of total cholesterol to HDL cholesterol increased by 40%. Total plasma triglycerides showed a slight upward trend. The extent of the fall in HDL cholesterol was directly proportional to the pre-treatment HDL cholesterol concentration. In 2 patients studied, treatment with Probucol produced a sustained increase in the excretion of endogenous faecal steroids, due to increased faecal bile acids. In 3 patients studied, Probucol increased the degree of cholesterol saturation in gall bladder bile. The Lithogenic Index approximated to pathological levels in 1 patient whose bile was previously relatively saturated with cholesterol. Probucol also appeared to cause a modest reduction in the degree of platelet activation in vivo, with reduced platelet prostaglandin synthesis and reduced release of platelet peptides.     

Treatment of type III hyperlipoproteinemia with four different treatment regimens

The efficacy of clofibrate (CPIB) and nicotinic acid (NA) in the treatment of type III hyperlipoproteinemia was evaluated in 5 male subjects in a randomized cross-over study with clofibrate 1 g b.i.d. and NA 3 g/day (given either b.i.d. or t.i.d.). Following a baseline period of 6 weeks, each drug was given for 12 weeks with samples for lipid and lipoprotein determinations obtained at 6, 9, and 12 weeks. Both clofibrate and NA resulted in a significant reduction from baseline of total cholesterol (23% and 28%), VLDL cholesterol (49% and 56%), total triglycerides (40% and 43%), and VLDL triglycerides (46% and 48%), as well as a significant increase in HDL cholesterol (22% and 28%) and HDL/LDL ratio (31% and 62%). The HDL/LDL ratio was higher on NA than clofibrate (0.47 +/- 0.19 vs. 0.38 +/- 0.09, P less than 0.05). Four subjects were continued in the study and treated sequentially with NA 3.0 g/day (alternate to the previous schedule) and gemfibrozil 1.2 g/d in divided doses. Each of the 4 regimens resulted in a significant change from baseline of each of the measured lipid and lipoprotein determinations except LDL cholesterol. Comparison among the treatment regimens revealed no differences except for significantly higher HDL cholesterol and HDL/LDL ratio with NA given t.i.d.