Serum lipoproteins and apolipoproteins in children during the first five years of diabetes

Serum lipoproteins and apolipoproteins were followed in 34 children during a period of 5 years from the onset of diabetes. The group did not differ in these respects from a healthy control group after 5 years of disease. The variation in serum triglycerides and very-low-density lipoprotein (VLDL) triglycerides was more pronounced, some patients having high values. Serum triglycerides and VLDL lipids were significantly correlated to subcutaneous fat, measured as triceps and subscapular skinfolds. None of the patients had albuminuria, so lipid levels could not be related to renal albumin excretion. There was no significant correlation between any serum lipid and haemoglobin A1c.

A crossover comparison of the efficacy and safety of lovastatin and gemfibrozil in the treatment of hyperlipidemic organ transplant recipients

Hypercholesterolemia is associated with accelerated atherosclerosis in transplant recipients. It has been notoriously difficult to treat pharmacologically due to the complex interactions that occur with lipid-lowering drugs and immunosuppressive therapies. The purpose of the current study was to compare the efficacy and safety of a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (lovastatin, 20 mg/d) with a fibric acid derivative (gemfibrozil, 600 mg twice a day). We used a randomized, crossover design in 18 solid organ transplant recipients who followed the National Cholesterol Education Program Adult Treatment Guidelines diet for 8 weeks and had persistent elevations of total cholesterol (>240 mg/dL). Each patient received each therapy for a minimum of 8 weeks (mean 14.2 +/- 2.4, range 8-20 weeks). The participants had stable allograft function and were treated with a standard immunosuppressive regimen containing cyclosporine, prednisone, and azathioprine. Lovastatin therapy reduced the mean total cholesterol by 15.5% (271.9 mg/dL to 229.9 mg/dL; p = 0.02) and the mean low-density lipoprotein (LDL) cholesterol by 22.7% (178.2 mg/dL to 137.8 mg/dL; p = 0.07). There were no significant changes in high-density lipoprotein (HDL) cholesterol or triglycerides. Conversely, when these same patients were treated with gemfibrozil, the mean total cholesterol decreased by 7.9% (271.9 mg/dL to 250.5 mg/dL; p = NS) and the LDL cholesterol decreased by 5.1% (178.2 mg/dL to 169.1 mg/dL; p = NS). In addition, the mean triglyceride concentration decreased significantly by 46.1% (234.0 mg/dL to 126.3 mg/dL; p = 0.002) and the mean HDL cholesterol increased 15.4% (48.8 mg/dL to 56.3 mg/dL; p = 0.09). In all patients, the serum creatinine, hepatocellular enzymes, and creatinine phosphokinase remained stable. Lovastatin was discontinued in three patients for myalgias, one patient with unexplained anemia, and one patient with parasthesias. These results suggest that lovastatin and gemfibrozil are both safe and efficacious in transplant patients. However, neither therapy alone completely corrects abnormalities of high LDL cholesterol and low HDL cholesterol in transplant recipients.

Insulin resistance: a common factor in the triad of dyslipidemia, hypertension, and coronary artery disease?

In addition to the goal of controlling elevated blood pressure in patients with hypertension improving Dyslipidemia associated with insulin resistance may be an important element in preventing coronary artery disease. Antihypertensive treatment may differ based on the pathophysiology present. It appears that the evidence that supports the development of lipid abnormalities in patients who have insulin resistance is growing. In such patients the morbidity and mortality associated with coronary artery disease may be significantly decreased by selecting agents with favourable metabolic consequences.

Management of obesity: medical treatment options

Obesity is a common and serious health problem in the United States. Excess weight is associated with an increased mortality rate, as well as such risk factors as hypertension, hyperlipidemia and diabetes mellitus. Numerous treatments are available for obesity. Behavioral therapy, surgery and pharmacologic treatment have been used with varying degrees of success. Pharmacologic therapy includes primarily noradrenergic agents and/or serotonergic agents. Newer preparations are currently under development. Behavior modification, including regular exercise and the development of healthy eating habits remains the best hope for long-term weight loss. However, surgery or medication can be useful in specific circumstances.

A difficult case. Childhood onset insulin dependent diabetes presenting with severe hyperlipidaemia

Confronted with a child deteriorating during treatment of diabetic ketoacidosis, Godfrey Nyamugunduru and Helen Roper describe how the child's management was complicated by gross hyperlipidaemia. At the point where the child's condition was deteriorating despite conventional management we invited two experts-Gilbert R Thompson and J I Mann-to suggest a course of action. The original authors then describe how they did manage the case, and our experts comment again.

The role of abdominal adiposity and insulin resistance in dyslipidemia of chronic renal failure

The atherogenic profile of high triglyceride, reduced high-density lipoprotein (HDL) cholesterol, and small low-density lipoprotein particle size found in patients on chronic hemodialysis is known to be associated with insulin resistance and abdominal obesity in the general population. To assess the influence of insulin resistance and abdominal adiposity on the lipid profile in subjects on hemodialysis, intravenous glucose tolerance test and dual-energy x-ray absorptiometry were performed in 26 nondiabetic subjects on hemodialysis and compared with 22 nondiabetic control subjects matched for age, sex, and body mass index. Subjects on hemodialysis were found to have higher triglyceride (133 mg/dL [95% confidence interval, 115 to 159 mg/dL] v 97 mg/dL [95% confidence interval, 80 to 124 mg/dL]; P < 0.05), lower HDL cholesterol (36 +/- 3 mg/dL v 51 +/- 4 mg/dL [mean +/- SEM]; P < 0.01), enhanced insulin response to glucose (2.72 +/- 0.28 mUL(-1) min per mg dL(-1) v 1.67 +/- 0.22 mUL(-1) min per mg dL(-1); P < 0.01), and reduced sensitivity to the action of insulin (2.24 min(-1) per mUL(-1) min [95% confidence interval, 1.86 to 2.75 min(-1) per mUL(-1) min] v 4.17 min(-1) mUL(-1) min [95% confidence interval, 2.95 to 5.9 min(-1) per mUL(-1) min]; P < 0.01) than the control subjects. Abdominal adiposity measured by dual-energy x-ray absorptiometry (2,004 +/- 210 g v 2,163 +/- 198 g [mean +/- SEM]; P = NS) and percentage of body fat distributed to the abdomen (10.5% +/- 0.3% v 9.7% +/- 0.5% [mean +/- SEM]; P = NS) did not differ between the two groups. Subjects on hemodialysis were insulin resistant, but unlike control subjects, their lipid profile was not predicted by their insulin sensitivity. Abdominal adiposity was associated with a deteriorating lipid profile and insulin resistance in subjects on hemodialysis, as it was in control subjects. The presence of renal failure resulted in additional insulin resistance and a higher triglyceride level in the leaner subjects on hemodialysis compared with control subjects with similar levels of abdominal fat. In the more obese subjects, insulin sensitivity and triglyceride level did not differ between the two groups of subjects, although HDL cholesterol level remained low in subjects on hemodialysis. In conclusion, insulin resistance in subjects on hemodialysis did not directly account for their abnormal lipid profile. The negative impact of abdominal adiposity on the metabolic profile was preserved in subjects on hemodialysis, but the presence of renal failure itself resulted in insulin resistance in the leaner subjects and dyslipidemia in all subjects on hemodialysis compared with control subjects of comparable abdominal adiposity.

Metabolic abnormalities in renal transplant recipients. Risk factors and predictors of chronic graft dysfunction?

In summary, abnormalities in lipid and carbohydrate metabolism, including features of the metabolic risk factor syndrome, are frequently present in patients both before and after renal transplantation. Risk factors of atherosclerosis may not only contribute to increased cardiovascular morbidity and mortality in this patient population, but can also be assumed to contribute to the development and progression of CVR and chronic graft dysfunction. For preventing both early graft losses and the development of graft damage leading to late graft dysfunction and graft loss, it appears to be essential to identify patients at risk early, prior to transplantation. Intervention aiming to reduce overweight, diet and exercise may be of benefit. The role of omega-3 unsaturated fatty acid supplementation remains controversial. Pharmacological intervention by antioxidants or agents to reduce lipids and/or decrease PAI-1 synthesis may prove to be beneficial. Early identification of patients at risk and intervention in due time may improve the results of renal transplantation.

Fluvastatin (Lescol) treatment of hyperlipidaemia in patients with renal transplants

Hyperlipidaemia of 18 male and 20 female patients following successful renal transplantation was treated with daily 20 mg fluvastatin (Lescol) for 12 weeks. The patients were several months after transplantation, and their total cholesterol levels exceeded 6.5 mmol/l following an 8-week diet. The effect of fluvastatin on the levels of total cholesterol, HDL, LDL, triglyceride, Apo A1 and Apo B, as well as of lipoprotein(a) was examined. Furthermore, changes of the renal function (GFR-urea, creatinine, uric acid) and hepatic function (bilirubin, GOT, GPT, CPK, ALP) were followed up, together with the body weight and blood pressure. The results of the examinations are summarized as follows: Fluvastatin may be administered effectively and without side effects in a daily dose of 20 mg in appropriately selected renal transplant patients. The average total cholesterol values, which were 7.91 mmol/l in men and 7.78 mmol/l in women following the diet, were reduced by 22-25% (p < 0.001) after 6 and 12 weeks, respectively, of fluvastatin treatment. The levels of LDL also decreased significantly (p < 0.001): in response to a 20 mg evening dosage, reduction of more than 25% was observed in 78% of men and 65% of women. Reductions of the Apo B levels were more pronounced in the females (18.3% men vs. 21.2% women). The ratio C/HDL-C decreased both in men (from 5.49 to 4.19) and in women (from 4.83 to 4.02). The ratio Apo B/Apo A1 also decreased (men: from 0.86 to 0.73, women: from 0.73 to 0.66). The concentrations of HDL and Apo A1 did not increase significantly, the reductions in the levels of triglyceride and lipoprotein(a) were not considerable either. An increase in the levels of hepatic enzymes and CPK was not encountered during the administration of fluvastatin. In two patients the levels of serum bilirubin increased by 2-4 micromol/l. Three patients complained about temporary myalgias of the sacroiliac or lumbar region which, however, were not accompanied by elevated CPK levels. The monitored levels of cyclosporine, urea and creatinine did not increase significantly during the 12 weeks of treatment. Two patients had temporary gastric complaints.

Effects of fluvastatin on hyperlipidemia after renal transplantation: influence of steroid therapy

OBJECTIVE

To assess the efficacy and safety of fluvastatin in hypercholesterolemic, cyclosporine-treated, renal transplant recipients, and to determine whether concomitant steroid therapy in such patients alters the lipid-lowering effects of fluvastatin.

DESIGN

An open-label, prospective, parallel study was performed in 20 cyclosporine-treated renal transplant recipients with hypercholesterolemia defined by a low-density lipoprotein (LDL) concentration greater than 160 mg/dL or a total cholesterol/high-density lipoprotein (HDL) concentration ratio greater than 5.0. Lipid profiles were measured before and 1 month after treatment with fluvastatin 20 mg/d. Lipid profiles in a group of patients receiving concomitant therapy with prednisone (n = 12) were compared with those of patients who had not received steroids for at least 6 months (n = 8).

SETTING

The Renal Transplant Clinic at University Hospitals of Cleveland.

MAIN OUTCOME MEASURES

The main outcome measures were serum concentrations of total cholesterol, LDL, HDL, and triglycerides. Treatment failure was defined by LDL concentrations persistently above 160 mg/dL after 1 month of fluvastatin therapy. Safety was assessed clinically and by serial measurements of liver enzymes and creatine phosphokinase.

RESULTS

LDL concentrations decreased significantly in both the steroid-treated and steroid-free groups after 1 month of fluvastatin therapy. There was no significant change in HDL concentrations or serum triglycerides in either group. Treatment failure was more common in patients receiving steroids (4/12 patients) than in steroid-free patients (1/8 patients). After 1 month of therapy, LDL cholesterol was significantly lower in the steroid-free group (126 +/- 18 mg/dL) than in the steroid-treated group (147 +/- 23 mg/dL) (p < 0.05). There was no clinical or laboratory evidence of myonecrosis in either group.

CONCLUSIONS

Low dosages of fluvastatin appear to be safe in cyclosporine-treated renal transplant recipients. Steroid-free patients exhibit a response to fluvastatin that is qualitatively similar to that of steroid-treated patients, consisting of a significant decrease in LDL concentrations and no change in HDL or serum triglyceride concentrations.

[Hyperuricemia and insulin resistance]

Hyperuricemia is often associated with obesity, hypertension and dyslipidemia, and is thought to be a risk factor for cardiovascular disease, thereby making resemblance to the insulin resistance syndrome. Our data showed a low, but significant correlation between serum uric acid concentration and the degree of insulin resistance (GIR) estimated by euglycemic hyperinsulinemic clamp method in 67 subjects with combined normal glucose tolerance and IGT(r = -0.278, p < 0.05). Plasma HDL-C and TG levels were also correlated with uric acid levels. One hundred sixty NIDDM patients who had undergone the clamp study were stratified into 5 groups according to the serum uric acid level. In the top quintile (UA : 7.8 +/- 0.8 mg/dl), BMI, male prevalence, plasma TG, HDL-C, fasting IRI, and total IRI response(0 + 60 + 120 min) during meal tolerance test were significantly higher, while age and GIR value tended to be lower without significance compared with those in the bottom quintile (UA : 3.4 +/- 0.5 mg/dl). These results, which are in agreement with the previous studies, support the notion that elevated serum uric acid is a feature of insulin resistance syndrome.

Bezafibrate. An update of its pharmacology and use in the management of dyslipidaemia

The lipid-modifying profile of bezafibrate is characterised by marked decreases in elevated triglyceride levels, increases in high density lipoprotein (HDL) cholesterol levels and decreases in total and low density lipoprotein (LDL) cholesterol levels. Bezafibrate also reduces elevated levels of lipoprotein(a) [Lp(a)] and fibrinogen, which are independent cardiovascular risk factors. Bezafibrate is effective in most types of primary and secondary dyslipidaemia. It is of greatest benefit in conditions featuring hypertriglyceridaemia and/or HDL cholesterol deficiency. This is particularly true for patients with diabetes mellitus, notably those with non-insulin-dependent diabetes mellitus (NIDDM) who are also likely to have increased fibrinogen levels. In the limited comparisons available, there appear to be few consistent differences in lipid-modifying effects between bezafibrate and other fibrates. Compared with HMG-CoA reductase inhibitors, bezafibrate causes larger changes in triglyceride and, in general, HDL cholesterol levels, and has a lesser influence on LDL and total cholesterol levels. These differences are advantageous when bezafibrate and HMG-CoA reductase inhibitors are used as combined therapy in patients with severe dyslipidaemia unresponsive to either modality alone. The combination of bezafibrate plus an HMG-CoA reductase inhibitor in clinical trials has not led to the predicted increase in myalgia. Indeed, bezafibrate is generally free of serious unwanted effects: rhabdomyolysis is rare and has occurred mainly in patients with renal dysfunction given excessive dosages. Other patient groups in whom bezafibrate has improved serum lipid profiles are those with isolated HDL cholesterol deficiency, dyslipidaemia secondary to renal insufficiency, and following cardiac surgery or other procedures. However, data for these indications are not extensive. Evidence is now available to show a beneficial effect of bezafibrate on retarding atherosclerotic processes and in reducing risk of coronary heart disease. The 5-year Bezafibrate Coronary Atherosclerosis Intervention Trial (BECAIT) in young male survivors of myocardial infarction demonstrated a smaller decrease in luminal diameter and a reduction in coronary events with bezafibrate compared with placebo. The Bezafibrate Infarction Prevention (BIP) study is expected to provide mortality data which is currently lacking for bezafibrate. In conclusion, bezafibrate is a useful and well-tolerated lipid-modifying agent in the management of primary and secondary dyslipidaemia. It has particularly beneficial effects in patients with hypertriglyceridaemia and/or low HDL cholesterol levels, and reduces fibrinogen levels. Together with its ability to sustain or improve glycaemic control, these properties make it a logical choice for treating patients with diabetes mellitus and dyslipidaemia. Additionally, the drug may be of value as combination therapy in patients with severe dyslipidaemia. Importantly, there is evidence that the drug can slow the atherosclerotic process and reduce cardiovascular morbidity. The ongoing BIP secondary intervention study and other investigations will help clarify the effects of bezafibrate on cardiovascular mortality and morbidity.

Impaired endothelium-dependent and independent dilatation of forearm resistance arteries in men with diet-treated non-insulin-dependent diabetes: role of dyslipidaemia

1. We measured endothelium-dependent and independent dilatation of forearm resistance arteries in 29 men with diet-treated non-insulin-dependent diabetes mellitus and 18 age- and sex-matched control subjects. None of the diabetic patients had hypercholesterolaemia, overt hypertension or microproteinuria. 2. We examined endogenous and exogenous nitric oxide-mediated vasodilatation by measuring forearm blood flow with venous occlusive plethysmography after administration of acetylcholine (7.5 and 15 micrograms/min) and sodium nitroprusside (3 and 10 micrograms/min), respectively, into the brachial artery. NG-monomethyl-L-arginine was also infused to study the inhibition of basal and stimulated release of nitric oxide. 3. The vasodilatory response to acetylcholine, expressed as area under curve, was significantly decreased in the diabetic patients compared with the control subjects (P = 0.019). NG-monomethyl-L-arginine significantly reduced basal (P < 0.001) and acetylcholine-stimulated blood flow (P < 0.02) in both groups. The vasodilatory response (also expressed as area under curve) to sodium nitroprusside was significantly less (P = 0.044) in the diabetic patients than in the control subjects. 4. In the diabetic patients, impaired vasodilatory responses to acetylcholine were significantly correlated with higher serum triacylglycerols (P = 0.048) and lower high-density lipoprotein-cholesterol concentrations (P = 0.007); the association with high-density lipoprotein was independent of age, glycated haemoglobin and blood pressure. Sodium nitroprusside responses were not correlated with lipid and lipoprotein concentrations. 5. We conclude that there is impaired endothelial and smooth muscle cell function in men with diet-treated non-insulin-dependent diabetes mellitus uncomplicated by overt hypertension or microproteinuria. Endothelial dysfunction may be related to diabetic dyslipidaemia and associated metabolic disturbances.

Hyperlipidemia after liver transplantation: natural history and treatment with the hydroxy-methylglutaryl-coenzyme A reductase inhibitor pravastatin

This study was designed to determine the frequency of hyperlipidemia after orthotopic liver transplantation and whether treatment with a hydroxy-methylglutaryl coenzyme A reductase inhibitor was safe and efficacious. Cholesterol levels were assessed in 45 consecutive adult liver transplants (mean +/- SE). Four of 22 patients on cyclosporine (CsA) (18%) and three of 23 patients on FK506 (13%) had levels >225 mg/dl at 12 months (cholesterol levels for patients on CsA [total n=22]: pre-Tx = 140+/-11, 1 month = 183+/-36,3 months = 221+/-12, 6 months = 211+/-11, 12 months = 202+/-14 [P<0.01 vs. pre-Tx]; FK506 [total n=23]: Pre-Tx = 151+/-13, 1 month = 187+/-22, 3 months = 188+/-10, 6 months = 184+/-13, 12 months = 164+/-9 [P=0.02 vs. CsA]). A separate cohort of patients with stable graft function, cholesterol >225 mg/dl, and two additional risk factors for coronary artery disease were started on pravastatin. Ninety-eight patients were enrolled. Sixteen patients (16%) discontinued the drug because of subjective complaints. No episodes of rhabdomyolysis or hepatotoxicity occurred (cholesterol levels for patients on CsA [total n=65]: pretreatment = 251+/-7, 6 months = 220+/-7 [P=0.01 vs. pretreatment], 12 months = 224+/-8 [P=0.01 vs. pretreatment]; FK506 [total n=17]: pretreatment = 251+/-17, 6 months = 219+/-17, 12 months = 208+/-17 [P=0.08 vs. pretreatment]). Natural killer cells isolated from normal volunteers (n=14) exhibited 27+/-9% specific lysis. Patients on FK506 or cyclosporine-based immunosuppression alone (n=11) exhibited 20+/-4% specific lysis. Standard immunosuppression plus pravastatin (n=10) decreased lysis to 0.2+/-10% (P<0.02 vs. controls and standard immunosuppression). We conclude: (1) posttransplant hyperlipidemia occurs less frequently in liver transplant patients than in renal or cardiac transplants; (2) pravastatin is safe and efficacious for cholesterol reduction in liver transplant patients; and (3) pravastatin coadministered with standard immunosuppression reduces natural killer cell-specific lysis in these recipients.

Serum lipid profiles in Malay mothers and neonates: a cross-sectional study

OBJECTIVE

Preliminary epidemiological data suggest that dyslipidaemia contributes significantly to rising mortality due to atherosclerosis in Peninsular Malays. The aim of this study was to determine whether abnormal serum lipid profiles are present at birth in this population.

METHODOLOGY

The patients were 487 non-diabetic Malay women who had an uncomplicated antenatal course and delivered healthy singleton babies at term. Cord blood and maternal post-partum venous blood samples were taken for assay of serum cholesterol and triglyceride concentrations using standard enzymatic methods.

RESULTS

Maternal total serum cholesterol concentrations (mean +/- SD; 7.5 +/- 2.5 mmol/L) were higher than in other reported series (range of published means 5.2-6.5 mmol/L) with a correspondingly low high-density lipoprotein (HDL): total cholesterol ratio. The mean cord blood total serum cholesterol (1.7 +/- 1.0 mmol/L) was consistent with previously reported population means (1.5-1.9 mmol/L) but there was a relatively high low-density lipoprotein (LDL)-cholesterol and depressed HDL: cholesterol ratio. Significant correlations between maternal and neonatal serum total (P = 0.038) and especially HDL-cholesterol (P < 0.001) were observed. Maternal and cord blood serum triglyceride levels were comparable to those in other series.

CONCLUSIONS

These cross-sectional data provide evidence that abnormal serum cholesterol profiles are found in pregnant Malay women and their neonates which may have implications for the prevalence of macrovascular disease in the Malay population.

Feeding rats the nitric oxide synthase inhibitor, L-N(omega)nitroarginine, elevates serum triglyceride and cholesterol and lowers hepatic fatty acid oxidation

This study was conducted to examine whether nitric oxide regulates lipid metabolism. In Experiment 1, rats were fed for 5 wk diets with or without 0.2 g/kg L-N-nitroarginine (L-NNA), a specific inhibitor of nitric oxide synthase, that were or were not supplemented with 40 g/kg L-arginine. Rats fed L-NNA had significantly higher concentrations of serum triglyceride and total cholesterol, lower concentrations of serum nitrate, and a lower ratio of HDL-cholesterol to total cholesterol than rats fed the basal diet. These alterations were suppressed by supplementing L-arginine to the L-NNA-containing diet. In Experiment 2, rats were fed diets with or without 0.2 g/kg L-NNA. Dietary L-NNA elevated serum concentrations of free fatty acids without affecting those of ketone bodies. L-NNA lowered the activity of hepatic carnitine palmitoyltransferase, the rate-limiting enzyme of fatty acid oxidation, but did not affect activities of hepatic glucose-6-phosphate dehydrogenase and fatty acid synthase which are lipogenic enzymes. These results suggest that the lower nitric oxide level in rats fed L-NNA leads to hyperlipidemia and that the elevation in serum triglyceride might be due to reduced fatty acid oxidation.