Gene expression profile following an oral unsaturated fat load in abdominal obese subjects.

PURPOSE: Our aim was to evaluate the postprandial effect of an oral fat load test (OFLT) rich in unsaturated fatty acids on gene expression profile in peripheral blood mononuclear cells (PBMC) from subjects with abdominal obesity as an insulin resistance model and controls. METHODS: A total of 20 controls and 20 abdominal obese patients were studied. Metabolic parameters and oxidative stress markers were measured with standardized protocols. The whole gene expression at fasting state and after the OFLT (0, 4 and 8 h) was analysed using human HT-12-v4 expression beadchips, from Illumina. RESULTS: We found a significant decrease in plasma glucose, insulin and oxidative stress markers in abdominal obese patients and controls. We found beneficial metabolic postprandial gene expression in three genes: FKBP5, DDIT4 and DHRS9. Following an OFLT, the postprandial mRNA expression of FKBP5, and DDIT4 was downregulated while that of DHRS9 was overexpressed, both in nondiabetic normolipidemic subjects and in insulin-resistant subjects with abdominal obesity. CONCLUSIONS: Our results suggest that an OFLT rich in unsaturated fatty acids downregulates the expression of FKBP5, coding for the glucocorticoid receptor pathway, and that of DDIT4, involved in the oxidative stress response. These changes could favourably influence the insulin resistance and oxidative stress status in the postprandial state.

Mediterranean diet adherence in individuals with prediabetes and unknown diabetes: the Di@bet.es Study.

BACKGROUND AND AIMS: Mediterranean diet (MedDiet) is causally related to diabetes and is a dietary pattern recommended to individuals with diabetes. We investigated MedDiet adherence in individuals with prediabetes and unknown (PREDM/UKDM) or known diabetes (KDM) compared to those with normal glucose metabolism (NORMAL). METHODS: This was a national, population-based, cross-sectional, cluster-sampling study. MedDiet adherence was scored (MedScore, mean ± SD 24 ± 5) using a qualitative food frequency questionnaire. Logistic regression was used to examine the association between MedScore and PREDM/UKDM or KDM versus control subjects. RESULTS: We evaluated 5,076 individuals. Mean age was 50 years, 57% were female, 826 (582/244) were PREDM/UKDM, 478 were KDM and 3,772 were NORMAL. Mean age increased across MedScore tertiles (46, 51 and 56 years, p < 0.0001). Higher age-adjusted adherence to MedDiet (5-unit increment in the MedScore) was associated with lower and nondifferent odds (OR, 95% CI) of prevalent PREDM/UKDM (0.88, 0.81-0.96, p = 0.001) and KDM (0.97, 0.87-1.07, p = 0.279), respectively, compared to individuals in the NORMAL group. CONCLUSIONS: In a representative sample of the whole Spanish population, MedDiet adherence is independently associated with PREDM/UKDM. Therapeutic intervention may be, in part, responsible for the lack of differences in adherence observed between the KDM and NORMAL groups. However, reverse causation bias cannot be ruled out in cross-sectional studies.

Establishing cut-off values for apolipoprotein B and non-HDL-C according to LDL-C values in a South European population.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) remains the primary target of therapy in most strategies of dyslipidaemia management focused on cardiovascular disease prevention. Different guidelines have identified specific LDL-C cut-off points as targets for therapeutic intervention. Many clinical situations characterised by dyslipidaemia and elevated triglycerides are common in our environment and in overall industrialised countries. Thus, lipid goals based only on LDL-C could misclassify an important percentage of subjects. The objective of the present study was to establish cut-off point values for apoB and non-HDL-C in relation to the identified LDL-C cut-off points for cardiovascular risk in a South European population. METHODS: We performed a cross-sectional study including 1501 subjects (770 women and 731 men) between 18 and 80 years of age. Samples were collected after 12-14 h of fasting. Cholesterol, HDL-C, triglycerides and apoB levels were measured using direct methods. LDL-C was calculated by the Friedewald formula. Non-HDL-C was calculated as total cholesterol minus HDL-C. RESULTS: The Spearman's rank correlations between apoB and LDL-C (r 0.86, p < 0.0001), and between apoB and non-HDL-C (r 0.91, p < 0.0001) were both significant. The proposed cut-off points for apoB, according to LDL-C goals (70, 100, 130 and 160 mg/dl) in our population are 70, 80, 100 and 115 mg/dl respectively. The proposed cut-off values for non-HDL-C are 100, 120, 150 and 190 mg/dl respectively. CONCLUSION: The established LDL-C cut-off values could not be accurate to estimate cardiovascular risk in subjects with mild hypertriglyceridaemia, as frequently occurs in our Mediterranean population. To take into consideration the burden of atherogenic particles and better classify patients at risk we propose cut-off values for apoB or the equivalent for non-HDL-C. Prospective trials including cardiovascular variables are needed to validate our assumption.

Prevalence of diabetes mellitus and impaired glucose regulation in Spain: the Di@bet.es Study.

AIMS/HYPOTHESIS: The Di@bet.es Study is the first national study in Spain to examine the prevalence of diabetes and impaired glucose regulation. METHODS: A population-based, cross-sectional, cluster sampling study was carried out, with target population being the entire Spanish population. Five thousand and seventy-two participants in 100 clusters (health centres or the equivalent in each region) were randomly selected with a probability proportional to population size. Participation rate was 55.8%. Study variables were a clinical and demographic structured survey, lifestyle survey, physical examination (weight, height, BMI, waist and hip circumference, blood pressure) and OGTT (75 g). RESULTS: Almost 30% of the study population had some carbohydrate disturbance. The overall prevalence of diabetes mellitus adjusted for age and sex was 13.8% (95% CI 12.8, 14.7%), of which about half had unknown diabetes: 6.0% (95% CI 5.4, 6.7%). The age- and sex-adjusted prevalence rates of isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT) and combined IFG-IGT were 3.4% (95% CI 2.9, 4.0%), 9.2% (95% CI 8.2, 10.2%) and 2.2% (95% CI 1.7, 2.7%), respectively. The prevalence of diabetes and impaired glucose regulation increased significantly with age (p < 0.0001), and was higher in men than in women (p < 0.001). CONCLUSIONS/INTERPRETATION: The Di@bet.es Study shows, for the first time, the prevalence rates of diabetes and impaired glucose regulation in a representative sample of the Spanish population.

Is the ADA/EASD algorithm for the management of type 2 diabetes (January 2009) based on evidence or opinion? A critical analysis.

The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin monotherapy and lifestyle modification, followed by addition of basal insulin or a sulfonylurea if glycaemic goals are not met (tier 1 recommendations). All other glucose-lowering therapies are relegated to a secondary (tier 2) status and only recommended for selected clinical settings. In our view, this algorithm does not offer physicians and patients the appropriate selection of options to individualise and optimise care with a view to sustained control of blood glucose and reduction both of diabetes complications and cardiovascular risk. This paper critically assesses the basis of the ADA/EASD algorithm and the resulting tiers of treatment options.

Circulating mononuclear cells nuclear factor-kappa B activity, plasma xanthine oxidase, and low grade inflammatory markers in adult patients with familial hypercholesterolaemia.

BACKGROUND: Few data are available on circulating mononuclear cells nuclear factor-kappa B (NF-kB) activity and plasma xanthine oxidase (XO) activity in heterozygous familial hypercholesterolaemia (FH). The goal of the study was to analyse circulating mononuclear cells NF-kB and plasma XO activities in FH patients. MATERIALS AND METHODS: Thirty FH index patients and 30 normoglycaemic normocholesterolaemic controls matched by age, gender, body mass index, abdominal circumference and homeostasis model assessment index were studied. Plasma XO and inflammatory markers were measured by standard methods. NF-kB was assayed in circulating mononuclear cells. RESULTS: Familial hypercholesterolaemia patients showed a significantly higher NF-kB (75.0 +/- 20.7 vs. 42.7 +/- 16.8 relative luminiscence units) and XO (0.44 +/- 0.13 vs. 0.32 +/- 0.09 mU mL(-1)) activities than controls. In addition, interleukin-1, interleukin-6, high sensitivity C reactive protein (hsCRP) and oxidized LDL (LDL-ox) were also significantly higher in FH patients. In the total group (FH and controls), XO was significantly associated with LDL-cholesterol (LDL-C), apolipoprotein B (apoB), NF-kB and hsCPR, and NF-kB activity was significantly associated with XO, hsCPR, LDL-ox, LDL-C and apoB plasma values. Using multiple regression analysis, XO was independently associated with hsCPR and NF-kB, and NF-kB activity in circulating mononuclear cells was independently associated with apoB and LDL-ox plasma values. CONCLUSION: Familial hypercholesterolaemia patients show increased activities of NF-kB and XO, and higher values of low grade inflammatory markers related to atherosclerosis. NF-kB activity was independently associated with apoB plasma values. These data could explain in part the high cardiovascular disease risk present in these patients.

Plasma homocysteine levels are associated with ulceration of the foot in patients with type 2 diabetes mellitus.

BACKGROUND: To examine the association of biochemical markers of risk (plasma Hcy, microalbuminuria, lipoprotein (a)(Lp(a)) and diabetic dyslipidaemia) with the prevalence of diabetic foot ulceration in type 2 diabetic patients. METHODS: Case/control study conducted in 198 type 2 diabetic patients. 89 patients have foot ulcers and 109 have no foot ulcers (control group), in order to establish ORs for diabetic foot ulceration. In all subjects plasma Hcy, Lp(a), total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, apolipoprotein B, HbA(1c) and microalbuminuria were measured using standard procedures. RESULTS: Plasma Hcy, microalbuminuria, HbA(1c) and apolipoprotein B levels were significantly higher in patients with foot ulceration compared with the control group. Plasma lipids, Lp(a), vitamin B12 and folic acid values were similar in both groups. In the logistic regression model, plasma Hcy (OR 1.09; 95% CI 1.04-1.69), microalbuminuria (OR 1,01; 95% CI 1.01-1.17) and HbA(1c) levels (OR 1.33; 95% CI 1.04-1.69) were independent risk factors for the presence of diabetic foot ulceration. CONCLUSIONS: In our study, for each micromol increase in plasma Hcy levels there was a 10% increase in the risk of diabetic foot ulceration. In addition, plasma homocysteine, HbA(1c) and microalbuminuria accounted for 50% prevalence risk of diabetic foot ulceration. Further prospective studies should be conducted to confirm the association of plasma Hcy levels with the risk of foot ulceration.

Increased plasma xanthine oxidase activity is related to nuclear factor kappa beta activation and inflammatory markers in familial combined hyperlipidemia.

BACKGROUND AND AIMS: Xanthine oxidase (XO) has been described as one of the major enzymes producing free radicals in blood. Oxidative stress and inflammatory processes have been implicated in the pathogenesis of endothelial dysfunction and the progression of atherosclerosis but until now, there is little data about the influence of vascular prooxidant systems and inflammation in familial combined hyperlipidemia (FCH). Our goal was to evaluate whether XO activity was altered in FCH and if it was related to the inflammatory process represented by NFkB, IL-6 and hsCRP, and assessing the correlation between XO activity and insulin resistance (IR). METHOD AND RESULTS: 40 Non-related subjects with FCH and 30 control subjects were included, all of them non-diabetic, normotensive and non-smokers. We measured lipid profile, glucose, insulin, uric acid, XO activity, malondialdehyde (MDA), IL-6 and hsCRP in plasma and NFkB activity in circulating mononuclear cells. Patients with FCH showed significantly higher levels of uric acid, XO activity, MDA, NFkB activity, IL-6 and hsCRP than controls. XO activity was independently related to NFkB activity with an odds ratio of 4.082; to IL-6 with an odds ratio of 4.191; and to IR with an odds ratio of 3.830. Furthermore, mean NFkB activity, IL-6 levels, and IR were highest in the highest percentile of XO activity. CONCLUSIONS: Subjects with FCH showed increased XO and NFkB activities and low grade inflammatory markers related to atherosclerosis. XO activity was correlated with higher inflammatory activity and IR. These data could explain, in part, the high cardiovascular disease risk present in these patients.

LDL particle size and composition and incident cardiovascular disease in a South-European population: The Hortega-Liposcale Follow-up Study.

BACKGROUND: The association of low-density lipoprotein (LDL) particle composition with cardiovascular risk has not been explored before. The aim was to evaluate the relationship between baseline LDL particle size and composition (proportions of large, medium and small LDL particles over their sum expressed as small-LDL %, medium-LDL % and large-LDL %) and incident cardiovascular disease in a population-based study. METHODS: Direct measurement of LDL particles was performed using a two-dimensional NMR-technique (Liposcale®). LDL cholesterol was assessed using both standard photometrical methods and the Liposcale® technique in a representative sample of 1162 adult men and women from Spain. RESULTS: The geometric mean of total LDL particle concentration in the study sample was 827.2 mg/dL (95% CI 814.7, 839.8). During a mean follow-up of 12.4 ±â€¯3.3 years, a total of 159 events occurred. Medium LDL particles were positively associated with all cardiovascular disease, coronary heart disease (CHD) and stroke after adjustment for traditional risk factors and treatment. Regarding LDL particle composition, the multivariable adjusted hazard ratios for CHD for a 5% increase in medium and small LDL % by a corresponding decrease of large LDL % were 1.93 (1.55, 2.39) and 1.41 (1.14, 1.74), respectively. CONCLUSIONS: Medium LDL particles were associated with incident cardiovascular disease. LDL particles showed the strongest association with cardiovascular events when the particle composition, rather than the total concentration, was investigated. A change in baseline composition of LDL particles from large to medium and small LDL particles was associated with an increased cardiovascular risk, especially for CHD.

[Difficult treatment of amiodarone-induced thyrotoxicosis: a case report]. / Dificultad en el tratamiento del hipertiroidismo por amiodarona. Presentación de un caso.

Amiodarone causes changes in thyroid function tests in about 15-20% of patients, inducing either hypothyroidism or thyrotoxicosis. The iodine load and the destructive thyroiditis caused by amiodarone produce thyrotoxicosis. We report a case of amiodarone-induced thyrotoxicosis diagnosed when investigating the reason for worsening of cardiac function. Prognosis and treatment of cardiac disorder were determined by thyrotoxicosis. The management needed a closed monitoring of thyroid function. Treatment was based on high doses of propylthiouracil and dexamethasone, but they couldn t control cardiac condition and surgery was warranted. When amiodarone-induced thyrotoxicosis is refractory to medical treatment, we believe surgery should be considered earlier.

Modulatory effect of erythrocytes on the platelet reactivity to collagen in IDDM patients.

Platelets participate in the atherothrombotic complications of diabetes. Recent data demonstrate that platelet reactivity can be modulated via cell-cell interactions with erythrocytes and neutrophils. In this study, platelet reactivity was evaluated in 30 IDDM patients. We used an analytical procedure that permits an independent evaluation of platelet activation (granule release, eicosanoid formation) and platelet recruitment (pro-aggregatory activity of cell-free releasates) after platelet stimulation with collagen in the presence or absence of other blood cells. The interaction between platelets and erythrocytes (hematocrit 40%) resulted in a marked enhancement of platelet activation (5HT, betaTG, TXA2 release) and recruitment in both patients and control subjects. The erythrocyte enhancement of platelet TXA2 synthesis and recruitment was significantly higher in the patients, while no differences were detected in platelet granule release. The elevated platelet recruitment in the IDDM patients was found to be due to 1) increased susceptibility of diabetic platelets to the prothrombotic effect of erythrocytes and 2) the greater response of diabetic platelets to their own cell-free releasate. Patients with poor metabolic control (elevated HbA1c) or longer evolution time had an even greater platelet recruitment. The presence of microalbuminuria is not related to the platelet recruitment. Since platelet recruitment is an essential step in thrombus growth, its enhancement may favor thrombotic complications in IDDM.

Molecular genetics of familial hypercholesterolemia in Spain: Ten novel LDLR mutations and population analysis.

Mutations underlying FH in Spain are largely unknown because only a few and limited surveys have been carried out on Spanish FH patients up to now. To gain information on this issue, we have analysed a group of 113 unrelated Spanish FH patients from an eastern area of Spain (Valencian Community). We have screened the LDLR gene by Southern blot and PCR-SSCP analysis to detect large rearrangements and small mutations, respectively. In addition, we have screened the Apo B gene for mutations known to cause FDB by PCR-SSCP analysis. We have identified a total of 47 different mutations in the LDLR gene (5 large rearrangements, and 42 small mutations, which were characterized by DNA sequencing), 19 of which have not been described in other populations (Valencia-1 to -4, 112insA, P160R, 790DelATGA, 920insTCAG, G642E, and the ten novel mutations E246A, 884delT, I289T, S305F, Q328X, Y354C, I603del, 2312-3C>A, V779M, and N804K). Three of these mutations (15%) were present in more than 1 proband, being mutation 112insA the most prevalent (frequency approximately 8%) in our sample. The Apo B gene R3500Q mutation was found in only one patient and no underlying defect was found in about 27% of patients. Our data support the notion that Spaniards represent a heterogeneous population with its own spectrum of LDLR gene mutations and that, in our population, FDB has a lower frequency or a milder expression than in central Europe countries.

Genetic diagnosis of familial hypercholesterolemia in a South European outbreed population: influence of low-density lipoprotein (LDL) receptor gene mutations on treatment response to simvastatin in total, LDL, and high-density lipoprotein cholesterol.

The aims of this study were to examine the presence of mutations in the low-density lipoprotein receptor gene among subjects clinically diagnosed with familial hypercholesterolemia and to analyze whether the molecular diagnosis helps to predict the response to simvastatin treatment in our familial hypercholesterolemia population. Fifty-five probands and 128 related subjects with familial hypercholesterolemia were studied. Genetic diagnosis was carried out following a three-step protocol based on Southern blot and PCR-single strand conformational polymorphism analysis. A randomized clinical trial with simvastatin was conducted in 42 genetically diagnosed subjects with familial hypercholesterolemia classified as carriers of null mutations (n = 22) and of defective mutations (n = 20). A mutation-causing familial hypercholesterolemia was identified in 46 probands (84%). In 41 of them (89%), a total of 28 point mutations were detected, 13 of which have not been previously described. The remaining five probands (11%) were carriers of large rearrangements. Familial hypercholesterolemia with null mutations showed a poor response to simvastatin treatment. The mean percentage reduction of plasma total and low-density lipoprotein cholesterol levels in these subjects were significantly lower (24.8 +/- 10.3 vs. 34.8 +/- 10.9, P = 0.04 and 30.0 +/- 39.8 vs. 46.1 +/- 18.2, P = 0.02, respectively) than in subjects with defective mutations. Baseline and posttreatment high-density lipoprotein cholesterol plasma values were significantly lower in subjects with familial hypercholesterolemia with null mutations (P < 0.001). In an outbreed Caucasian population, a three-step protocol for genetic screening detected a mutation in the low-density lipoprotein receptor gene in a high percentage (84%) of subjects with familial hypercholesterolemia. Subjects with familial hypercholesterolemia with null mutations (class I) showed lower plasma high-density lipoprotein cholesterol values and a poor low-density lipoprotein cholesterol response to simvastatin treatment.

Coexisting dysbetalipoproteinemia and familial hypercholesterolemia. Clinical and laboratory observations.

Type III dysbetalipoproteinemia and familial hypercholesterolemia (FH) are two metabolic disorders giving rise to severe disturbances of lipid homeostasis and premature atherosclerosis. Both metabolic abnormalities have a genetic basis and co-occurrence in the same patient has seldom been described. Because of the unique structure of the French Canadian population, there was an opportunity to observe patients with both dysbetalipoproteinemia (E2/2 homozygotes) and FH (N=14) and to compare their clinical data with that of patients with type III (N=75), patients with FH (N0.7 and the presence of beta-VLDL on electrophoresis. Presence of a low density lipoprotein receptor, LDL-R, mutation should be suspected in a type III patient with a LDL-C level above 3.0 mmol/l and a family history of premature CAD. In the group of patients studied, the coexistence of dysbetalipoproteinemia and heterozygous FH does not appear to increase the prevalence of cardiovascular complications above that observed among control type III or control E3/3-FH patients. Thus, the presence of two epsilon2 alleles in these patients affects the expression of the abnormal LDL-R allele and the resulting phenotype substantiates the non additive effects of alleles at these two loci (epistasis).

Effect of olive and sunflower oils on low density lipoprotein level, composition, size, oxidation and interaction with arterial proteoglycans.

The atherogenicity of low density lipoproteins (LDL) may be modulated by its serum levels, structure and affinity for components of the intima, all properties that can be altered by diet. Linoleic acid-rich diets (n-G, 18:2) reduce the levels of LDL whereas those rich in oleic (n-9,18:1) are considered 'neutral'. However, LDL enriched in linoleic acid have been reported to be more vulnerable to free radical-mediated oxidation than those enriched in oleic, a potentially atherogenic property. The effect of dietary fats on other properties of LDL that may also modulate atherogenesis, such as size and capacity to interact with intima components, are not well established. We explored here how a change from an olive oil-rich diet (OO) to a sunflower oil-rich one (SFO) affects these parameters in a community with a traditional Mediterranean diet. Eighteen free-living volunteers were placed for 3 weeks on a diet with 31% of caloric intake as sunflower oil and then shifted for an additional 3 weeks to a diet in which OO provided 30.5% of the calories. The LDL after SFO had a fatty acids ratio of (18:2 + 18:3 + 20:4) to (16:0 + 16:1 + 18:0 + 18:1) of 1.06 +/- 0.11 compared to 0.73 +/- 0.06 after the OO period. Serum LDL was significantly lower after SFO than after OO. Unexpectedly, copper-catalyzed oxidation of LDL from the SFO period was significantly less than that of the particles from the OO period. The resistance to oxidation of LDL of the SFO and OO period related to alterations in content of the antioxidants alpha-tocopherol, beta-carotene and retinol, in addition to changes in size and fatty acids composition. In vitro binding of LDL to human arterial proteoglycans was also significantly lower for the SFO-LDL than the OO-LDL, a result that can also be attributed to the larger size of the SFO-LDL. Therefore, three properties of LDL: circulating levels, oxidizability, and affinity with intima proteoglycans, that may modulate its atherogenicity, were shifted in a favorable direction by diets rich in linoleic acid and natural antioxidants.

Influence of genetic variation at the apo A-I gene locus on lipid levels and response to diet in familial hypercholesterolemia.

We have examined the apo AI - 75 (G/A) and apo AI + 83(MspI +/-) polymorphisms at the APOA1 gene locus for associations with plasma lipid levels and response to an NCEP-I diet in 69 (44 women, 25 men) heterozygotes for familial hypercholesterolemia (FH). Subjects were studied at baseline (after consuming for one month a diet with 35%, fat, 10% saturated, and 300 mg/day cholesterol) and after 3 months of an NCEP-I diet. No gender-related differences for any of the lipid variables examined were found and the data were analyzed for men and women combined. For the apo AI - 75 (G/A) polymorphism, there were 51 G/G and 18 G/A subjects. At baseline, G/A subjects showed significantly lower total cholesterol (p = 0.0036), and LDL-C (p = 0.0023), and apo B (p = 0.0209), than G/G individuals, but no differences were found for HDL-C, triglycerides and VLDL-C values. Following the NCEP-I diet these genotype-related differences remained significant for total and LDL-C. The MspI (-) allele at the apo AI + 83 polymorphism was detected in the heterozygous state in five subjects and its presence was not associated with altered baseline lipids nor with dietary response to the NCEP-I diet. Our results suggest that FH subjects carrying the A allele at the apoAI - 75 (G/A) polymorphism have significantly lower total and LDL-C and apo B baseline levels but respond to a low-fat diet with similar reductions in total and LDL-C when compared with homozygotes for the G allele at this polymorphic site.

Hyperinsulinemia as a determinant of microalbuminuria in essential hypertension.

OBJECTIVE: To analyze the relationship between insulinemia and urinary albumin excretion in a group of nonobese, young adult hypertensive patients, who had never been treated with antihypertensive drugs. PATIENTS AND METHODS: Forty-nine patients who fulfilled the inclusion criteria were included. Twenty-four-hour ambulatory blood pressure monitorings, urinary albumin excretion (UAE) measurements, and an oral glucose-tolerance test measuring glucose and insulin, were performed, and left ventricular mass was measured by echocardiography. Hypertensive patients were classified as normoalbuminuric when their UAE was < 30 mg/24 h (40 patients; mean UAE 13.4 +/- 7.0 mg/24 h), and as microalbuminuric when their UAE was 30-300 mg/24 h (nine patients; mean UAE 90.5 +/- 86.6 mg/24 h). RESULTS: In comparison with that of the normoalbuminuric group, the fasting plasma glucose concentration for the microalbuminuric group was only slightly higher (100 +/- 9 versus 95 +/- 8 mg/dl, NS). In contrast, the fasting insulin concentration in the microalbuminuric group was significantly higher than that observed in the normoalbuminuric group (25.2 +/- 6.7 versus 16.6 +/- 5.2 microU/ml, P<0.0001). During the oral glucose-tolerance test, the area under the curve (AUC) for glucose (317 +/- 41 versus 253 +/- 53 mg/dl x 2/h, P<0.001) and the AUC for insulin (253 +/- 171 versus 124 +/- 43 microU/ml x 2/h, P<0.001) were significantly higher in the microalbuminuric group than were those AUC observed in the normoalbuminuric group. After adjustments for age, sex, body mass index and average 24 h ambulatory mean blood pressure were made, the fasting insulin level was associated independently with an increase in UAE in a multiple regression model with base 10 logarithm of the UAE as the dependent variable. Variations in fasting insulin level alone accounted for 33% of the UAE variance. In contrast, the 24 h ambulatory mean blood pressure, rather than the insulin level, was the strongest predictor of the left ventricular mass index. CONCLUSIONS: Mild hypertensive patients with microalbuminuria were hyperinsulinemic in the absence of obesity, and their insulin level was the main determinant of microalbuminuria in these patients. Microalbuminuria in essential hypertension seems to identify patients with a cluster of cardiovascular risk factors and a bad risk profile. Thus, assessment of microalbuminuria may be useful in the stratification of risk in essential hypertension.

Insulin resistance in patients with familial combined hyperlipidemia and coronary artery disease.

The minimum model modified by the administration of insulin provides an objective and relatively easily measured index of peripheral sensitivity to insulin which was significantly lower (p <0.02) in familial combined hyperlipidemia (FCH) with ischemic heart disease (IHD) than in FCH without IHD and in control subjects (1.2 +/- 0.6, 1.9 +/- 1.0, 2.9 +/- 1.2 x 10(-4) mU/L/ min, respectively). In patients with FCH, insulin resistance explains, at least in part, their metabolic alterations (hypertension, abnormal glucose tolerance, hyperinsulinemia) and elevated IHD.

The response to lovastatin treatment in patients with heterozygous familial hypercholesterolemia is modulated by apolipoprotein E polymorphism.

In a retrospective study, we examined the influence of apolipoprotein (apo) E polymorphism and gender on the response to treatment with 80 mg/d lovastatin in a homogeneous population of patients with familial hypercholesterolemia (FH), most of whom were carriers of the 10-kb deletion of the low-density lipoprotein (LDL) receptor gene. Apo E phenotype distribution among the 189 FH patients was not different from that of a normal population sample. The total and LDL cholesterol (LDL-C) response to lovastatin in the overall group (men and women) was significantly lower in the E4 subset compared with E2 and E3 subsets. This finding is in agreement with trends observed in previous reports. On the other hand, the response of LDL-C to lovastatin was significantly lower in E4 men than in E4 women, whereas the high-density lipoprotein cholesterol (HDL-C) concentration in the E4 group increased significantly more in men than in women, suggesting a role of gender in modulating the response to lovastatin. Hence, apo E polymorphism influenced LDL-C (and HDL-C) response to lovastatin in men, but not in women, revealing the existence of a gene-by-gender interaction. These findings were independent of the nature of the LDL receptor defect. We conclude that male FH patients carrying the epsilon 4 allele respond less efficiently to lovastatin than men carrying the epsilon 3 or epsilon 2 allele or women of any apo E phenotype with respect to decreasing total cholesterol and LDL-C levels, but respond more efficiently with respect to increasing HDL-C levels. The full practical implication of these findings remains to be explored.

Lipoprotein phenotype and insulin resistance in familial combined hyperlipidemia.

The study objective was to investigate the relationship of insulin resistance (IR) with the lipoprotein phenotype in familial combined hyperlipidemia (FCH). Thirty-seven FCH men diagnosed by clinical and biochemical criteria and classified as lipoprotein phenotype IIa (n = 9), IIb (n = 17), or IV (n = 11) were compared with a healthy control group of 30 men of similar age, body mass index (BMI), waist to hip ratio (WHR), and systolic and diastolic blood pressure. In all subjects, the plasma lipoprotein profile and baseline and post-oral glucose tolerance test (OGTT) glucose and insulin plasma values were measured. An intravenous glucose tolerance test was performed and IR was studied by the peripheral insulin sensitivity index (Si). After the OGTT, significantly higher values for insulinemia (at 0, 60, 90, and 120 minutes) and the area under the curve (AUC) of insulin secretion were observed in FCH. The AUC of insulin was greater in FCH subjects with the hypertriglyceridemic phenotype as compared with the controls and significantly lower Si levels, indicating greater IR, were found in the three FCH groups (control, 3.48 +/- 1.87 mU/L/min; FCH IIa, 2.09 +/- 1.08; FCH IIb, 1.54 +/- 0.77; FCH IV, 1.47 +/- 0.93; P < .001). The prevalence of IR (Si < 2 x 10(-4) mU/L/min) was greater in FCH, independent of the lipoprotein phenotype, as compared with the controls (P < .0001). Higher plasma glucose and insulin levels at 120 minutes and lower Si values were found in the FCH IIa group compared with the controls (P < .05), indicating a state of IR in this subgroup of normotriglyceridemic subjects. In conclusion, IR was found in the three FCH lipoprotein phenotypes, being more severe in subjects with hypertriglyceridemia. Hence, the therapeutic goals in FCH should include measures to normalize plasma lipids and improve peripheral insulin sensitivity.