Effects of atorvastatin on the clearance of triglyceride-rich lipoproteins in familial combined hyperlipidemia.

Familial combined hyperlipidemia (FCHL) patients have an impaired catabolism of postprandial triglyceride (TG)-rich lipoproteins (TRLs). We investigated whether atorvastatin corrects the delayed clearance of large TRLs in FCHL by evaluating the acute clearance of Intralipid (10%) and TRLs after oral fat-loading tests. Sixteen matched controls were included. Atorvastatin reduced fasting plasma TG (from 3.6 +/- 0.4 to 2.5 +/- 0.3 mM; mean +/- SEM) without major effects on fasting apolipoprotein B48 (apoB48) and apoB100 in large TRLs. Atorvastatin significantly reduced fasting intermediate density lipoprotein (Svedberg flotation, 12-20)-apoB100 concentrations. After Intralipid, TG in plasma and TRL showed similar kinetics in FCHL before and after atorvastatin treatment, although compared with controls, the clearance of large TRLs was only significantly slower in untreated FCHL, suggesting an improvement by atorvastatin. Investigated with oral fat-loading tests, the clearance of very low density lipoprotein (Sf20-60)-apoB100 improved by 24%, without major changes in the other fractions. The most striking effects of atorvastatin on postprandial lipemia in FCHL were on hepatic TRL, without major improvements on intestinal TRLs. Fasting plasma TG should be reduced more aggressively in FCHL to overcome the lipolytic disturbance causing delayed clearance of postprandial TRLs.

Acromegaly and heart failure: revisions of the growth hormone/insulin-like growth factor axis and its relation to the cardiovascular system.

Cardiomyopathy is a major cause of death in overt acromegaly. Recent progress in research has increasingly revealed the molecular mechanisms concerning growth hormone and insulin-like growth factor in the development of heart failure. In this article, we propose mechanisms according to which heart failure occurs, and we aim to extrapolate this knowledge to more general processes involved in heart failure.

Metformin and lactic acidosis: cause or coincidence? A review of case reports.

OBJECTIVE: Metformin has been associated with the serious side-effect lactic acidosis. However, it remains unclear whether the use of metformin was a cause or a coincidence in lactic acidosis. DESIGN: A literature search of the Index Medicus (1959-66) and of the databases Embase, Medline, Medline Express (1966-99) was performed using the keywords metformin, biguanides and lactic acidosis. All articles of cases with metformin-induced lactic acidosis (MILA) were cross-referenced. SUBJECTS: Cases were included for analysis if they met the following criteria: serum pH < or =7.35, lactate concentration > or =5 mmol L(-1). INTERVENTION: A forum of six experts in intensive care medicine independently categorized the cases in MILA unlikely (score 0), possible MILA (score 1) or probable MILA (score 2). MAIN OUTCOME MEASURES: Statistical analysis included the paired interobserver agreement (kappa) and multivariate regression analysis. RESULTS: Of 80 reported cases, 33 were excluded because of insufficient quality. The forum scores of the remaining 47 cases were distributed normally with a mean score of 7 (range 2-10). The kappa-value was 0.041 (SD = 0.24, range -0.514, 0.427). Neither lactate concentration nor mortality correlated with serum metformin concentrations. CONCLUSIONS: Given the low interobserver agreement and the lack of any relationship between metformin levels and outcome parameters, the concept that there is a simple, causal relationship between metformin use and lactic acidosis in diabetic patients has to be reconsidered.

Normalization of daytime triglyceridemia by simvastatin in fasting normotriglyceridemic patients with premature coronary sclerosis.

Postprandial hyperlipidemia is associated with premature coronary sclerosis in fasting normolipidemic subjects. Self-determined daytime capillary triglyceride (cTG) profiles were compared between 26 fasting normotriglyceridemic patients with premature coronary artery disease (CAD) and 26 controls matched for gender, age and BMI. Daytime triglyceridemia was calculated as total area under the cTG-curve (cTG-AUC). Total and LDL cholesterol were not different between CAD patients (5.4+/-0.8 mmol/l and 3.6+/-0.7 mmol/l, respectively) and controls (5.0+/-0.9 mmol/l and 3.3+/-0.8 mmol/l, respectively). Patients with CAD were characterized by a 44% higher cTG-AUC than matched controls (P<0.01). Using logistic regression analysis, cTG-AUC was the strongest predictor of the presence of CAD (P<0.001). Adding apo AI to the model improved the predictive power from 71 to 77%. Sixteen patients were studied after increasing doses of simvastatin up to 80 mg/day. Although the target for LDL cholesterol was reached by simvastatin 20mg/day, significant effects on cTG-AUC were found only by higher doses of simvastatin. Simvastatin 40 mg/day decreased cTG-AUC by 28% (P<0.05 versus baseline), reaching comparable values as in controls, without further improvement with simvastatin 80 mg/day (26% reduction versus baseline; P<0.05). Daytime triglyceridemia is linked to premature coronary sclerosis in fasting normotriglyceridemic patients. A higher dose of simvastatin was needed to normalize daytime triglyceridemia than was required to "normalize" LDL cholesterol.

[The growth hormone/insulin-like growth factor axis. What is its role in the atherosclerotic process?]. / L'axe hormone de croissance/insulin-like growth factor. Quel rôle dans le processus athéroscléreux?

UNLABELLED: GROWTH HORMONE AND ATHEROSCLEROSIS: Adult-onset growth hormone (GH) deficiency is associated with an increase in cardiovascular morbidity and mortality. MECHANISMS: Other than classical risk factors, such as dyslipidemia, a direct interaction between the activity of the GH/IGF-1 axis and the endothelium also plays a part. It is possible that the modulating effect of IGF-1 on nitric oxide (NO) synthesis is also important, together with the anabolic effect on the myocardiocytes. Substitution of recombinant GH induces rapid reduction in the atherosclerotic plaques, suggesting a direct effect of the GH/IGF axis on the atherosclerotic process. In addition to the acquired GH deficiency, as in non-substituted patients following hypophysectomy, attention has recently been focused on the relative GH deficiency as is seen in obesity and in the course of ageing. PERSPECTIVES FOR CARDIOVASCULAR ENDOCRINOLOGY: Therapeutic intervention in the GH/IGF axis might influence the atherosclerotic process. Study of the GH/IGF axis activity and of its correlation with atherosclerosis opens new perspectives in the understanding of the role of this axis in cardiovascular diseases.

Fasting and daylong triglycerides in obesity with and without type 2 diabetes.

Postprandial hypertriglyceridemia associated with insulin resistance is one of the cardiovascular risk factors in obesity and type 2 diabetes. It is not known whether diabetics have a more pronounced postprandial hypertriglyceridemia than obese subjects. Daylong triglyceridemia, representing postprandial lipemia, was determined in obese subjects with and without type 2 diabetes and in lean subjects. Nineteen type 2 diabetics (F/M: 7/12, body mass index [BMI]: 30.6 +/- 5.4 kg/m(2)), 45 obese nondiabetics (F/M: 16/29, BMI: 29.5 +/- 2.6 kg/m(2)) and 78 lean subjects (F/M: 28/50, BMI: 23.7 +/- 2.2 kg/m(2)) measured capillary triglycerides (TGc) during 3 days on 6 fixed time-points each day in an out-of-hospital situation. Daylong TGc profiles were calculated as mean integrated area under the TGc-curve (TGc-AUC). Fasting plasma TG were higher in diabetics and obese nondiabetics (1.81 +/- 0.79 and 1.77 +/- 0.80 mmol/L) compared with lean subjects (1.23 +/- 0.67 mmol/L, P <.001). TGc-AUC was similarly increased in both diabetics and obese nondiabetics (35.0 +/- 12.1 and 35.2 +/- 10.6 mmol.1 h/L) compared with lean controls (25.5 +/- 12.0 mmol.1 h/L, P <.001). Self-reported energy intake was not significantly different between the groups. Fasting TGc (r =.87, P <.001) and waist circumference (r =.51, P <.001) were the parameters best associated with TGc-AUC. Using stepwise multiple regression analysis, fasting TGc, BMI, total cholesterol, and high-density lipoprotein (HDL) cholesterol were the best predictors of TGc-AUC, explaining 77% of the variation. The cut-off level for "normal" TGc-AUC, calculated as the 75th percentile of TGc-AUC in lean subjects, was 30.7 mmol.1 h/L and corresponded with a fasting TGc of 1.8 mmol/L (eg, 1.6 mmol/L in plasma), calculated using univariate regression analysis. In conclusion, daylong triglyceridemia is similarly increased in diabetics and obese nondiabetics compared with lean subjects. Fasting TG and central obesity largely determine daylong triglyceridemia, independent of the presence of type 2 diabetes. Decreasing fasting plasma TG below 1.6 mmol/L could lead to a normalization of postprandial lipemia in obese subjects with and without diabetes.

Gender differences in postprandial ketone bodies in normolipidemic subjects and in untreated patients with familial combined hyperlipidemia.

OBJECTIVE: An increased hepatic flow of free fatty acids (FFAs) is associated with impaired peripheral FFA trapping by malfunctioning of the complement component 3 (C3)/acylation-stimulating protein system and overproduction of VLDL in familial combined hyperlipidemia (FCHL). Postprandial ketone bodies reflect FFA oxidation in the liver, but the postprandial changes in male and female patients separately have not been determined yet. Gender differences in postprandial ketone bodies and C3 changes were investigated in normolipidemic patients and patients with untreated FCHL. METHODS AND RESULTS: Thirty-two normolipidemic patients (16 female and 16 male) and 19 patients with untreated normolipidemia (9 female and 10 male) underwent an oral fat-loading test. Total and incremental areas under the curves (AUC and dAUC, respectively) after the oral fat load were calculated. Triglyceride AUC was similar between genders in each group. Normolipidemic female subjects showed a higher levels of dAUC-hydroxybutyric acid than male subjects (1.37+/-0.49 and 0.98+/-0.43 mmol x h/L). In FCHL, a similar trend was observed in female (1.92+/-0.38) compared with male (1.55+/-0.87) subjects. In contrast to normolipidemia, FCHL did not show a postprandial increase in C3, although C3 was higher in FCHL. CONCLUSIONS: Women have higher postprandial ketone bodies than men, probably reflecting enhanced postprandial hepatic FFA oxidation. In FCHL, both genders have higher postprandial ketone bodies and therefore higher hepatic FFA delivery. The higher fasting and postprandial C3 levels in FCHL may reflect resistance of the C3/acylation-stimulating protein system to promote peripheral fatty acid trapping.

Six-month efficacy of benfluorex vs. placebo or metformin in diet-failed type 2 diabetic patients.

Six-month efficacy of benfluorex (Mediator) (150-450 mg/day) was assessed in a double-blind multicenter study vs. placebo or metformin hydrochloride (850-2550 mg/day). After a 2-month run-in period of strict dieting, 722 type 2 diabetic patients were randomized (1:2:2) to receive placebo (n=144), benfluorex (n=294) or metformin (n=284). After a 5-week dose-finding phase, the efficacy of benfluorex was compared with that of placebo (test for difference, main analysis) and metformin (non-inferiority test, secondary analysis) during a 6-month fixed-dose treatment. At entry after strict dieting, there was no difference between groups for HbA(1C) (placebo, 7.4%+/-1.5%; benfluorex, 7.7%+/-1.6%; metformin, 7.8%+/-1.6%) and fasting plasma glucose (FPG; placebo, 9.7+/-2.3 mmol/l; benfluorex, 10.0+/-2.0 mmol/l; metformin, 10.2+/-2.5 mmol/l). At the end of the dose-finding phase, mean doses were 2.71 tablets/day for placebo group, 2.65 tablets/day for benfluorex (397.5 mg/day) and 2.50 tablets/day for metformin (2125 mg/day). At the end of treatment, HbA(1C) level decreased by 0.60% ( p<0.001) in benfluorex patients while it increased by 0.50% ( p<0.001) with placebo (intent-to-treat analysis). The mean endpoint difference was -0.86% (SE, 0.17%; p<0.001). Mean endpoint difference in HbA(1C) between benfluorex and metformin was 0.28% (SE, 0.12%) [90% CI, 0.07 to 0.48] (non-inferiority test, p=0.037). Treatment with benfluorex was well tolerated; 39% of these patients reported one or more emergent adverse events (compared to 38% on placebo and 43% on metformin) and only two patients suffered a treatment-related, serious adverse event. This study demonstrates that benfluorex: (1) significantly reduces HbA1C and fasting plasma glucose when compared to placebo; (2) has a good safety profile; and (3) has relatively lower potency compared to metformin, although the non-inferiority test (equivalence limit for HbA(1C) of 0.5%) was significant.

Induction of postprandial inflammatory response in adult onset growth hormone deficiency is related to plasma remnant-like particle-cholesterol concentration.

Increased cardiovascular mortality due to premature atherosclerosis is a clinical feature in the adult-onset GH deficiency (AGHD) syndrome. Inflammation is a key feature in atherogenesis and may be triggered by postprandial lipoprotein remnants. We hypothesized that increased postprandial lipoprotein remnant levels in AGHD may be associated with an inflammatory response. In this case-control study, 10 AGHD patients [6 males and 4 females; age, 48 +/- 9 yr; body mass index (BMI), 26.9 +/- 2.6 kg/m(2)] and 10 healthy control subjects (matched for age, BMI, gender, baseline lipid levels, and apolipoprotein E genotype) were included. They all ingested an oral fat load. Fasting and postprandial levels of plasma remnant-like particle-cholesterol (RLP-C; 0.31 +/- 0.13 mmol/liter and 4.14 +/- 1.37 mmol/liter.h in GHD; 0.18 +/- 0.06 mmol/liter and 2.56 +/- 1.02 mmol/liter.h in controls, respectively) were significantly increased in AGHD patients compared with control subjects. The median inflammatory cytokines, IL-6 and TNF-alpha, were higher in the fasting [3.9 (range, 3.1-11.9) pg/ml and 6.8 (range, 2.5-27.6) pg/ml, respectively] and postprandial [151.7 (range, 87.0-294.3) pg/ml.24 h and 289.9 (range, 87.5-617.6) pg/ml.24 h, respectively] states in AGHD than in controls [fasting, 0.9 (range, 0.2-5.2) pg/ml and 2.8 (range, 2.5-5.7) pg/ml; and postprandial, 54.5 (range, 11.50-126.5) pg/ml.24 h and 118.3 (range, 81.2-243.1) pg/ml.24 h, respectively]. In addition, postprandial profile of RLP-C and IL-6 in AGHD and in the total group were significantly associated (r(2) = 0.44, P < 0.05; and r(2) = 0.38, P < 0.01, respectively). In conclusion, the increased postprandial RLP-C level in GHD is associated with an inflammatory response that may result in increased susceptibility for premature atherosclerosis.

Delayed and exaggerated postprandial complement component 3 response in familial combined hyperlipidemia.

Very low density lipoprotein overproduction is the major metabolic characteristic in familial combined hyperlipidemia (FCHL). Peripheral handling of free fatty acids (FFAs) in vitro may be impaired in FCHL by decreased action of acylation-stimulating protein (ASP), which is identical to the immunologically inactive complement component 3a (C3adesArg). Because decreased FFA uptake by impaired complement component 3 (C3) response (as the precursor for ASP) may result in enhanced FFA flux to the liver in FCHL, we have evaluated postprandial C3 changes in vivo in FCHL patients. Accordingly, 10 untreated FCHL patients and 10 matched control subjects underwent an oral fat loading test. Fasting plasma C3 and ASP levels were higher in FCHL patients (1.33+/-0.09 g/L and 70.53+/-4.37 mmol/L, respectively) than in control subjects (0.91+/-0.03 g/L and 43.21+/-8.96 mmol/L, respectively; P=0.01 and P<0.05). In control subjects, C3 concentrations increased significantly after 4 hours (to 1.03+/-0.04 g/L). In FCHL, plasma C3 was unchanged after 4 hours. The earliest postprandial C3 rise in FCHL patients occurred after 8 hours (1.64+/-0.12 g/L). The maximal apolipoprotein B-48 concentration was reached after 6 hours in FCHL patients and control subjects. Postprandial FFA and hydroxybutyric acid (as a marker of hepatic FFA oxidation) were significantly higher in FCHL patients than in control subjects, and the early postprandial C3 rise was negatively correlated with the postprandial FFA and hydroxybutyric acid concentrations. The present data suggest an impaired postprandial plasma C3 response in FCHL patients, most likely as a result of a delayed response by C3, as the precursor for the biologically active ASP, acting on FFA metabolism. Therefore, an impaired postprandial C3 response may be associated with impaired peripheral postprandial FFA uptake and, consequently, lead to increased hepatic FFA flux and very low density lipoprotein overproduction.

In vivo modulation of plasma free fatty acids in patients with familial combined hyperlipidemia using lipid-lowering medication.

One of the best studied aspects of the insulin resistance syndrome in familial combined hyperlipidemia (FCHL) is impaired insulin-mediated suppression of FFA by diminished inhibition of hormone-sensitive lipase (HSL). In vitro experiments have shown that stimulation of HSL activity by catecholamines is decreased in FCHL. The aim of this study was to investigate HSL inhibition by insulin and stimulation by endogenous catecholamines in vivo in FCHL patients. Twelve FCHL subjects using lipid-lowering medication and 12 controls underwent a mental stress test after random ingestion of either 50 g glucose or placebo. After ingestion of glucose, insulin concentrations increased from 76.8 +/- 21.5 pM to a maximum of 520.2 +/- 118.4 pM (P < 0.01) in FCHL and from 38.0 +/- 5.0 to 221.7 +/- 25.1 pM (P < 0.01) in controls. The percent decreases in plasma FFA during the first hour after glucose ingestion were similar in FCHL and controls (67 +/- 5% vs. 72 +/- 3%, respectively), suggesting a comparable inhibition of HSL in both. During the placebo test, FFA increased similarly in FCHL (56 +/- 9%) and controls (57 +/- 19%). In contrast, FFA concentrations did not change during mental stress after ingestion of glucose (from 0.17 +/- 0.02 to 0.15 +/- 0.02 mmol/liter in FCHL and from 0.11 +/- 0.02 to 0.12 +/- 0.02 mmol/liter in controls). In conclusion, the present study provides in vivo evidence for intact insulin-mediated suppression of FFA in FCHL, although this inhibition of HSL was achieved by higher insulin levels, suggesting insulin resistance at the level of HSL. Secondly, the induction of HSL activity by endogenous catecholamines in vivo is not decreased in FCHL, in contrast to earlier in vitro findings. Finally, catecholamine-induced HSL activation can be inhibited by insulin in a similar manner in both FCHL and controls.

Primary and secondary prevention in cardiovascular disease: an old-fashioned concept?

OBJECTIVE: Is the concept of primary and secondary cardiovascular prevention an old-fashioned concept that needs to be re-defined? DESIGN: Discussion paper. RESULTS: Cardiovascular prevention means reduction of absolute risk for cardiovascular disease (CVD), irrespective of clinical stage. CONCLUSION: For the calculation of an individual probability to develop CVD all factors that contribute to the risk must be taken into account, including previous CVD events.

[Free fatty acids: mediators of insulin resistance and atherosclerosis]. / Vrije vetzuren: mediatoren van insulineresistentie en atherosclerose.

Free fatty acids (FFAs) are involved in the transportation of energy; in the postprandial phase to the peripheral tissues and in the postabsorptive phase from the adipose tissue to the liver. In the postprandial phase, FFAs are mainly derived from hydrolysis of triglyceride-rich particles like chylomicrons and very low-density lipoproteins (VLDL). The flux of FFAs is directed to peripheral cells such as adipocytes and muscle cells. In the postabsorptive period, FFAs are transported to the liver after being released from intracellular storage in the adipocytes. Complement component 3 (C3) plays an important role in the uptake of free fatty acids by the peripheral cells and their esterification to triglycerides. Since C3 is also involved in the pathogenesis of the insulin resistance syndrome, and since a deviant FFA metabolism with an increased FFA flux to the liver may induce insulin resistance, it is hypothesized that C3 may form the missing link between FFA metabolism and insulin resistance. In addition, recent studies have increasingly indicated that atherosclerosis is in fact an inflammation-based process involving complement-dependent responses, in which FFAs seem to play a role in the complement-dependent pathway. It has recently become apparent that FFAs have a regulatory function in the transcription of DNA, in relation to lipoprotein metabolism. This is where PPAR-gamma and PPAR-alpha agonists ('glitazones' and fibrates respectively) are active (PPAR is an abbreviation for peroxisome proliferation activating receptor). Glitazons may play an important role in the treatment of insulin resistance and related disorders. Acquiring more knowledge about the relationship between complement and FFA metabolism may increase our understanding of these processes and provide openings for the development of new antiatherogenic strategies.

Differential effect of female gender on coronary artery disease and peripheral artery disease.

BACKGROUND: Women are relatively protected against coronary artery disease (CAD). Whether female gender has a similar protective influence on the development of peripheral artery disease (PAD) has not been extensively investigated and was the main subject of our study. METHODS: We analysed 2707 consecutive patients (2008 men and 699 women) who underwent a first diagnostic coronary angiography for suspicion of CAD and 2367 consecutive patients (1426 men and 941 women) who underwent a first ankle arm index measurement because of suspicion of PAD. RESULTS: We found that a positive diagnosis for CAD and PAD was more common in men compared with women (80.7% vs 57.9%, p<0.0001 and 68.0% vs 60.7%, p<0.0001). Once CAD or PAD was established, severity of disease was similar for men and women, which pleads against a referral bias. Women had a reduced risk of CAD after adjustment for risk factors (odds ratio [OR] 0.32, 95% confidence interval [CI] 0.22-0.46, p<0.0001), but not of PAD (OR 0.82, 95% CI 0.66-1.03, p=NS). In patients with CAD and in those with PAD, women were older, more often had diabetes and hypertension, while men were more likely to be current smokers. Hypertension, smoking and diabetes were associated with CAD in both men and women. Current smoking was associated with PAD in men and women. Hypertension and diabetes were associated with PAD in women but not in men. CONCLUSION: After adjustment for risk factors, the female protection for CAD seems to less present for PAD.

Insulin resistance syndrome and type 2 diabetes mellitus.

Patients with type 2 diabetes mellitus have an elevated risk of morbidity and mortality from cardiovascular disease. This risk is partly attributable to an increased prevalence of classic coronary artery disease risk factors and partly because of hyperglycemia itself and a highly atherogenic lipid profile. The altered composition of lipoproteins and lipids in type 2 diabetic patients, termed diabetic dyslipidemia, is characterized by: (1) elevated levels of triglyceride; (2) normal levels of total and low-density lipoprotein cholesterol (LDL-C); (3) reduced levels of high-density lipoprotein cholesterol (HDL-C); (4) elevated levels of apolipoprotein B; (5) a preponderance of small, dense LDL particles; and (6) increased levels of cholesterol-rich very-low-density lipoprotein. In most cases, diabetic dyslipidemia is preceded by hyperinsulinemia resulting from insulin resistance. Because patients with type 2 diabetes and insulin resistance are at a markedly increased risk of atherosclerosis, and because strict control of glycemia has proved beneficial in reducing microangiopathy but not macroangiopathy, treatment of diabetic dyslipidemia should be aggressive. Target levels have, therefore, been set at <2.6 mmol/L (100 mg/dL) for LDL-C, <2.3 mmol/L [200 mg/dL] for triglycerides, and >1.15 mmol/L (45 mg/dL) for HDL-C. Trial data suggest that these target levels are likely to be achieved with statins, if necessary, in combination with fibrates or nicotinic acid derivatives. Furthermore, in large-scale clinical trials (eg, Scandinavian Simvastatin Survival Study [4S] and the Cholesterol and Recurrent Events [CARE] study), it has been demonstrated that lipid lowering can appreciably reduce cardiovascular events in diabetic patients.