Abstract WP219: Lipoprotein Subfractions Are Associated With Stroke Among 9,795 Patients in the Field Trial

Background: In the FIELD trial, a 5-year randomized double-blind placebo-controlled trial of fenofibrate vs. placebo in 9,795 adults with type 2 diabetes (T2D), the only standard lipid parameter correlating with microvascular (renal) events was triglycerides. Given the high prevalence of stroke among diabetic patients, we explored associations between lipoprotein subfractions and risk for stroke in the FIELD trial.

Methods: We performed ultracentrifugation using the vertical auto profile (VAP, Atherotech) on plasma (baseline and after 6 weeks of fenofibrate). Analyses were performed using Cox proportional hazards and logistic regression for new on-study events. Results were adjusted for gender and fenofibrate or placebo allocation.

Results: HDL related analytes (HDL-C, HDL3-C, apo A1, apoA2) correlated with reduced risk for all stroke. LDL and its subfractions and Lp(a)-C did not. VLDL and its subfractions, non-HDL-C, triglycerides, apo B, apo En, various ratios incorporating apo C3, and the ratios of apoB/A1 and apoB/apoA2 all correlated with increased risk for stroke.

Conclusions: VAP identifies multiple lipoprotein subclasses, apoproteins, and VAP subclass/apoprotein ratios associated with stroke. Many of these measures improved with fenofibrate therapy.

The effect of alogliptin and pioglitazone combination therapy on various aspects of β-cell function in patients with recent-onset type 2 diabetes

OBJECTIVE

Type 2 diabetes mellitus (T2DM) management requires continuous treatment intensification due to progressive decline in β-cell function in insulin resistant individuals. Initial combination therapy of a dipeptidyl peptidase (DPP)-4 inhibitor with a thiazolidinedione (TZD) may be rational. We assessed the effects of the DPP4 inhibitor alogliptin (ALO) combined with the TZD pioglitazone (PIO), vs ALO monotherapy or placebo (PBO), on β-cell function and glycemic control in T2DM.

MATERIAL AND METHODS

A 16-week, two-center, randomized, double-blind, PBO-controlled, parallel-arm intervention study in 71 patients with well-controlled T2DM (age 59.1±6.3 years; A1C 6.7±0.1%) treated with metformin, sulfonylurea, or glinide monotherapy was conducted. Patients were treated with combined ALO 25 mg and PIO 30 mg daily or ALO 25 mg daily monotherapy or PBO. Main outcome measures included change in A1C and fasting plasma glucose (FPG) from baseline to week 16. In addition, change in β-cell function parameters obtained from standardized meal tests at baseline and at week 16 was measured.

RESULTS

ALO/PIO and ALO decreased A1C from baseline by 0.9±0.1 and 0.4±0.2% respectively (both P<0.001 vs PBO). FPG was decreased to a greater extent by ALO/PIO compared with ALO monotherapy (P<0.01). ALO/PIO treatment improved β-cell glucose sensitivity (vs PBO; P<0.001) and fasting secretory tone (vs PBO; P=0.001), while ALO monotherapy did not change β-cell function parameters. All treatments were well tolerated.

CONCLUSION

Short-term treatment with ALO/PIO or ALO improved glycemic control in well-controlled T2DM patients, but only combined ALO/PIO improved β-cell function. These data support that initial combination therapy with a DPP4 inhibitor and TZD to address multiple core defects in T2DM may be a sensible approach.

Acquired liver fat is a key determinant of serum lipid alterations in healthy monozygotic twins

OBJECTIVE

The effects of acquired obesity on lipid profile and lipoprotein composition in rare BMI-discordant monozygotic (MZ) twin pairs were studied.

DESIGN AND METHODS

Abdominal fat distribution, liver fat (magnetic resonance imaging and spectroscopy), fasting serum lipid profile (ultracentrifugation, gradient gel-electrophoresis, and colorimetric enzymatic methods), and lifestyle factors (questionnaires and diaries) were assessed in 15 BMI-discordant (within-pair difference [Δ] in BMI >3 kg/m2) and nin concordant (ΔBMI <3 kg/m2) MZ twin pairs, identified from two nationwide cohorts of Finnish twins.

RESULTS

Despite a strong similarity of MZ twins in lipid parameters (intra-class correlations 0.42-0.90, P < 0.05), concentrations of apolipoprotein B (ApoB), intermediate-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein 3a% (HDL3a%), and HDL3c% were higher (P < 0.05) and those of HDL cholesterol, HDL2-C, and HDL2b% were lower (P < 0.01) in the heavier co-twins of BMI-discordant pairs. The composition of lipoprotein particles was similar in the co-twins. When BMI-discordant pairs were further divided into liver fat-discordant and concordant (based on median for Δliver fat, 2.6%), the adverse lipid profile was only seen in those heavy co-twins who also had high liver fat. Conversely, BMI-discordant pairs concordant for liver fat did not differ significantly in lipid parameters. In multivariate analyses controlling for Δsubcutaneous, Δintra-abdominal fat, sex, Δsmoking and Δphysical activity, Δliver fat was the only independent variable explaining the variation in ΔApoB, Δtotal cholesterol, and ΔLDL-C concentration.

CONCLUSIONS

Several pro-atherogenic changes in the amounts of lipids but not in the composition of lipoprotein particles were observed in acquired obesity. In particular, accumulation of liver fat was associated with lipid disturbances, independent of genetic effects.

Heritability and familiality of type 2 diabetes and related quantitative traits in the Botnia Study

AIMS/HYPOTHESIS

To study the heritability and familiality of type 2 diabetes and related quantitative traits in families from the Botnia Study in Finland.

METHODS

Heritability estimates for type 2 diabetes adjusted for sex, age and BMI are provided for different age groups of type 2 diabetes and for 34 clinical and metabolic traits in 5,810 individuals from 942 families using a variance component model (SOLAR). In addition, family means of these traits and their distribution across families are calculated.

RESULTS

The strongest heritability for type 2 diabetes was seen in patients with age at onset 35-60 years (h (2) = 0.69). However, including patients with onset up to 75 years dropped the h (2) estimates to 0.31. Among quantitative traits, the highest h (2) estimates in all individuals and in non-diabetic individuals were seen for lean body mass (h (2) = 0.53-0.65), HDL-cholesterol (0.52-0.61) and suppression of NEFA during OGTT (0.63-0.76) followed by measures of insulin secretion (insulinogenic index [IG(30)] = 0.41-0.50) and insulin action (insulin sensitivity index [ISI] = 0.37-0.40). In contrast, physical activity showed rather low heritability (0.16-0.18), whereas smoking showed strong heritability (0.57-0.59). Family means of these traits differed two- to fivefold between families belonging to the lowest and highest quartile of the trait (p < 0.00001).

CONCLUSIONS/INTERPRETATION

To detect stronger genetic effects in type 2 diabetes, it seems reasonable to restrict inclusion of patients to those with age at onset 35-60 years. Sequencing of families with extreme quantitative traits could be an important next step in the dissection of the genetics of type 2 diabetes.

Acute suppression of VLDL1 secretion rate by insulin is associated with hepatic fat content and insulin resistance

AIMS/HYPOTHESIS

Overproduction of VLDL(1) seems to be the central pathophysiological feature of the dyslipidaemia associated with type 2 diabetes. We explored the relationship between liver fat and suppression of VLDL(1) production by insulin in participants with a broad range of liver fat content.

METHODS

A multicompartmental model was used to determine the kinetic parameters of apolipoprotein B and TG in VLDL(1) and VLDL(2) after a bolus of [(2)H(3)]leucine and [(2)H(5)]glycerol during a hyperinsulinaemic-euglycaemic clamp in 20 male participants: eight with type 2 diabetes and 12 control volunteers. The participants were divided into two groups with low or high liver fat. All participants with diabetes were in the high liver-fat group.

RESULTS

The results showed a rapid drop in VLDL(1)-apolipoprotein B and -triacylglycerol secretion in participants with low liver fat during the insulin infusion. In contrast, participants with high liver fat showed no significant change in VLDL(1) secretion. The VLDL(1) suppression following insulin infusion correlated with the suppression of NEFA, and the ability of insulin to suppress the plasma NEFA was impaired in participants with high liver fat. A novel finding was an inverse response between VLDL(1) and VLDL(2) secretion in participants with low liver fat: VLDL(1) secretion decreased acutely after insulin infusion whereas VLDL(2) secretion increased.

CONCLUSIONS/INTERPRETATION

Insulin downregulates VLDL(1) secretion and increases VLDL(2) secretion in participants with low liver fat but fails to suppress VLDL(1) secretion in participants with high liver fat, resulting in overproduction of VLDL(1). Thus, liver fat is associated with lack of VLDL(1) suppression in response to insulin.

Long-term effects of fenofibrate on VLDL and HDL subspecies in participants with type 2 diabetes mellitus

AIMS/HYPOTHESIS

Low HDL-cholesterol (HDL-C) is frequently accompanied by high triacylglycerol levels in diabetic dyslipidaemia, increasing the risk of CHD. In the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study, fenofibrate treatment lowered triacylglycerol levels, but the initial 5% increase in HDL-C attenuated over 5 years. We explored the changes in VLDL and HDL subspecies during fenofibrate treatment in a statin-free FIELD cohort.

METHODS

We randomised 171 participants with type 2 diabetes mellitus, who had been recruited to the FIELD study in Helsinki, to micronised fenofibrate (200 mg/day) or placebo in double-blind study design. VLDL and HDL subspecies were separated by ultracentrifugation at baseline and at the second and fifth year. Apolipoprotein (apo)A-I and apoA-II were measured by immunoturbidometric methods and lipoprotein (Lp)A-I and LpAI-AII particles by differential immunoassay.

RESULTS

Fenofibrate reduced plasma triacylglycerol levels by 26%, resulting from a marked reduction in VLDL1 triacylglycerol (0.62 vs 0.29 mmol/l, p < 0.001). Fenofibrate caused an increase in LDL size (Delta 0.80 nm, p < 0.001). HDL-C was similar between the groups. HDL2-C was decreased by fenofibrate (-27.5% at 5th year, p < 0.001) and HDL3-C increased (13.0% at 5th year, p < 0.001). Fenofibrate had no effect on apoA-I, whereas apoA-II increased. Thus, LpA-I decreased while LpAI-AII increased. Activities of cholesteryl ester transfer protein, phospholipids transfer protein and lecithin:cholesterylacyl transferase were unchanged by fenofibrate. High homocysteine levels were associated with a slight decrease in HDL-C and apoA-I.

CONCLUSIONS/INTERPRETATION

Fenofibrate markedly reduced large VLDL particles and produced a clear shift in HDL subspecies towards smaller particles. The HDL3-C increase in conjunction with unchanged apoA-I [corrected] levels is a dilemma with regard to cardiovascular disease.

Impact of postprandial lipaemia on low-density lipoprotein (LDL) size and oxidized LDL in patients with coronary artery disease

BACKGROUND

Remnant lipoprotein particles (RLPs) and oxidative stress are components of postprandial state. We investigated the concentrations of triglyceride-rich lipoproteins (TRLs), RLPs, low-density lipoprotein (LDL) size, and oxidized LDL (oxLDL) during alimentary lipaemia, and evaluated whether changes among these variables could be associated with the severity and extent of coronary artery disease (CAD).

MATERIALS AND METHODS

Eighty men and 27 women with clinically suspected CAD underwent quantitative coronary angiography (QCA). TRLs were isolated by density gradient ultracentrifugation before and 6 h after an oral fat load. RLPs were measured by an immunoseparation method, oxLDL by ELISA, and LDL size by gradient gel electrophoresis.

RESULTS

Triglycerides, apolipoprotein (apo) B-48, and apoB-100 concentration in Swedberg flotation units (Sf) > 400 and in Sf 12-400 fractions were markedly increased at 6 h. Postprandial cholesterol content of RLPs (RLP-C) correlated with respective triglycerides in Sf > 400 (r = 0.737) and Sf 12-400 (r = 0.857), apoB-48 in Sf > 400 (r = 0.710) and Sf 12-400 (r = 0.664), apoB-100 in Sf > 400 (r = 0.812) and Sf 12-400 (r = 0.533). RLP-C correlated with oxLDL both in fasting and in fed state (r = 0.482 and r = 0.543, respectively) and inversely with LDL size (r = -0.459 and r = -0.442, respectively). (P < 0.001 for all). OxLDL was elevated postprandially (P < 0.001). In multivariate analysis, oxLDL was a determinant of severity and extent of CAD.

CONCLUSION

Postprandial state is associated with oxidative stress. The magnitude of oxLDL increases during alimentary lipaemia and is associated with coronary atherosclerosis.

Effects of long-term fenofibrate therapy on cardiovascular events in 9795 people with type 2 diabetes mellitus (the FIELD study): randomised controlled trial

BACKGROUND

Patients with type 2 diabetes mellitus are at increased risk of cardiovascular disease, partly owing to dyslipidaemia, which can be amenable to fibrate therapy. We designed the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study to assess the effect of fenofibrate on cardiovascular disease events in these patients.

METHODS

We did a multinational, randomised controlled trial with 9795 participants aged 50-75 years, with type 2 diabetes mellitus, and not taking statin therapy at study entry. After a placebo and a fenofibrate run-in phase, we randomly assigned patients (2131 with previous cardiovascular disease and 7664 without) with a total-cholesterol concentration of 3.0-6.5 mmol/L and a total-cholesterol/HDL-cholesterol ratio of 4.0 or more or plasma triglyceride of 1.0-5.0 mmol/L to micronised fenofibrate 200 mg daily (n=4895) or matching placebo (n=4900). Our primary outcome was coronary events (coronary heart disease death or non-fatal myocardial infarction); the outcome for prespecified subgroup analyses was total cardiovascular events (the composite of cardiovascular death, myocardial infarction, stroke, and coronary and carotid revascularisation). Analysis was by intention to treat. The study was prospectively registered (number ISRCTN 64783481).

FINDINGS

Vital status was confirmed on all but 22 patients. Averaged over the 5 years' study duration, similar proportions in each group discontinued study medication (10% placebo vs 11% fenofibrate) and more patients allocated placebo (17%) than fenofibrate (8%; p<0.0001) commenced other lipid treatments, predominantly statins. 5.9% (n=288) of patients on placebo and 5.2% (n=256) of those on fenofibrate had a coronary event (relative reduction of 11%; hazard ratio [HR] 0.89, 95% CI 0.75-1.05; p=0.16). This finding corresponds to a significant 24% reduction in non-fatal myocardial infarction (0.76, 0.62-0.94; p=0.010) and a non-significant increase in coronary heart disease mortality (1.19, 0.90-1.57; p=0.22). Total cardiovascular disease events were significantly reduced from 13.9% to 12.5% (0.89, 0.80-0.99; p=0.035). This finding included a 21% reduction in coronary revascularisation (0.79, 0.68-0.93; p=0.003). Total mortality was 6.6% in the placebo group and 7.3% in the fenofibrate group (p=0.18). Fenofibrate was associated with less albuminuria progression (p=0.002), and less retinopathy needing laser treatment (5.2%vs 3.6%, p=0.0003). There was a slight increase in pancreatitis (0.5%vs 0.8%, p=0.031) and pulmonary embolism (0.7%vs 1.1%, p=0.022), but no other significant adverse effects.

INTERPRETATION

Fenofibrate did not significantly reduce the risk of the primary outcome of coronary events. It did reduce total cardiovascular events, mainly due to fewer non-fatal myocardial infarctions and revascularisations. The higher rate of starting statin therapy in patients allocated placebo might have masked a moderately larger treatment benefit.

Study of agreement between LDL size as measured by nuclear magnetic resonance and gradient gel electrophoresis

LDL particle size can be measured by gradient gel electrophoresis (GGE) and NMR. The agreement between the two methods has not been extensively evaluated. Therefore, we measured LDL size by NMR and GGE in 324 individuals (152 with type 1 diabetes and 172 controls). The Spearman correlation between both methods was 0.39 [95% confidence interval (CI) = 0.29, 0.48]. The average difference was 5.38 nm (NMR being smaller), but it increased with increasing LDL size. Less than 50% of people classified as pattern B on GGE were classified as pattern B on NMR (kappa = 0.31; 95% CI = 0.17, 0.45). Agreement was lower for diabetic subjects compared with controls, for women compared with men, and for subjects with triglycerides less than 1.30 mmol/l compared with subjects with triglycerides greater than 1.30 mmol/l. External validation showed that cholesteryl ester transfer rate was related to LDL size on GGE in all subgroups and to LDL size on NMR only in men and nondiabetic subjects. Our findings show that agreement between NMR- and GGE-based LDL size is far from perfect and is not consistent across subgroups of patients. In particular, the two methods should not be assumed to be interchangeable in women and diabetic subjects. Whether NMR or GGE predicts cardiovascular disease risk better has not yet been evaluated.

Associations between HDL oxidation and paraoxonase-1 and paraoxonase-1 gene polymorphisms in families affected by familial combined hyperlipidemia

BACKGROUND AND AIM

It has been shown in vitro that the HDL-bound enzyme paraoxonase-1 (PON1) protects LDL against oxidation, and PON1 and PON1 gene polymorphisms may affect the oxidation of HDL particles. The aim of this study was to investigate the associations between in vitro HDL oxidation parameters, endogenous PON1 and PON1 genotypes in families affected by asymptomatic FCHL.

METHODS AND RESULTS

Serum arylesterase (ARE) and PON1 activities, PON1 mass, PON1 genotypes and the kinetics of CuSO4-induced HDL oxidation in vitro were measured in 150 members of FCHL families free of clinical CAD. At univariate analysis, log PON1/apoA-I and the PON1 mass/apoA-I ratio significantly correlated with lag time, maximum diene formation and the propagation rate. The oxidation parameters also correlated with PON1 genotypes. Multivariate analysis showed that the associations between PON1 mass/unit apoA-I and the oxidation parameters were independent of the other variables. The lag time of HDL oxidation was also associated with the PON1 genotype 192QR.

CONCLUSIONS

Endogenous PON1 may have protective effects on the different stages of HDL oxidation in the members of families affected by FCHL. This protective effect is independent of other biochemical factors, but may be influenced by the PON1 gene polymorphism. The endogenous PON1 content of HDL seems to be an important determinant of the anti-atherogenicity of this lipoprotein.

Controlling lipid levels in diabetes

Coronary heart disease (CHD) is associated with a 2- to 4-times greater risk of morbidity and mortality in patients with type 2 diabetes than in non-diabetic individuals. Dyslipidaemia is an important CHD risk factor in diabetic patients. The key atherogenic features of diabetic dyslipidaemia are elevated levels of serum triglycerides, low levels of high density lipoprotein (HDL) cholesterol, and the preponderance of small, dense low density lipoprotein (LDL). As a result, treatment guidelines for diabetic dyslipidaemia recommend elevated LDL cholesterol and triglyceride levels and low HDL cholesterol levels as targets of therapy. Unfortunately, however, these lipid abnormalities often persist despite best efforts to control hyperglycaemia, improve diet, and increase physical exercise, and therefore demand specific therapeutic intervention. Statins are the first choice for LDL cholesterol lowering as they are effective and well tolerated, and do not have adverse effects on glycaemic control. Furthermore, recent evidence suggests that statins may also be employed to treat moderately elevated levels of triglycerides. An increasing number of primary and secondary prevention trials have shown that lipid-lowering therapy with statins can significantly reduce the risk of CHD events in patients with diabetic dyslipidaemia.

Lipoprotein subclasses and particle sizes and their relationship with coronary artery calcification in men and women with and without type 1 diabetes

Type 1 diabetes is associated with increased coronary atherosclerosis, especially in women, even though such patients often have an apparently normal lipid profile. We examined whether lipoprotein particle sizes and subclasses differed between type 1 diabetic subjects (n = 194, age 30-55 years) and age- and sex-matched control subjects (n = 195). We examined whether any abnormalities were of similar magnitude in men and women. The relationship of particle size to electron beam computer tomography-defined coronary artery calcification, a measure of atherosclerosis, was also examined. Proton nuclear magnetic resonance (NMR) spectroscopy was used to quantify VLDL, LDL, and HDL subclass levels and average particle size on fasting samples. LDL size and subclass were similar in diabetic and nondiabetic men. In contrast, in women diabetes was associated with less large and more small LDL and a reduced LDL size (mean difference 0.2 nm; P = 0.0009). This greater effect of diabetes on LDL size in women compared with men was significant (P = 0.007). Diabetes was associated with more large and less small HDL and, to a similar degree in both sexes, a higher HDL size (difference of 0.4 nm in men and 0.3 nm in women; both P < 0.0001). There were no definitive abnormalities in VLDL size. In nondiabetic subjects, lower average HDL particle size, lower LDL size, and higher VLDL size were significantly associated with coronary calcification (P = 0.001, 0.02, and 0.04, respectively). Thus the HDL size differences with diabetes would be expected to be antiatherogenic and the LDL size differences pro-atherogenic. However, there was no clear relationship between particle size and calcification in diabetic subjects. We conclude that in the general population NMR spectroscopy-derived particle size reveals important information about the atherogenicity of lipoprotein profile. Type 1 diabetes is associated with differences in NMR-derived particle size, but their pathogenic significance is unclear.

Pathogenesis of dyslipidemia in type 2 diabetes

The recognition that hypertriglyceridemia is associated with multiple alterations of other lipoproteins that are potentially atherogenic has expanded the picture of diabetic dyslipidemia. Elevation of large VLDL1 particles initiate a sequence of events that results in generation of atherogenic lipoproteins including remnants and small dense LDL. This abnormality is also associated with the lowering of HDL cholesterol. The clinical implication is that the concentration of plasma triglycerides should be maintained as low as possible to avoid these deleterious consequences of hypertriglyceridemia.

Differing associations of lipid and lipoprotein disturbances with the macrovascular and microvascular complications of type 1 diabetes

OBJECTIVE

Cardiovascular disease (CVD) is increased in patients with type 1 diabetes, but lipid and lipoprotein patterns remain favorable. In contrast, nephropathy is associated with an adverse distribution. We compared the associations and predictive power of lipid and lipoprotein disturbances with these complications.

RESEARCH DESIGN AND METHODS

A nested case-control study from the EURODIAB cohort of 140 case subjects with evidence of at least one complication and 84 control subjects with no complications were analyzed. Conventional and unconventional lipid and lipoprotein fractions, including apolipoprotein (apo)-A1, lipoprotein (Lp)-A1, LpA1/A2, apoB, and LDL particle size were measured centrally.

RESULTS

CVD was only associated with increased LDL cholesterol (3.6 vs. 3.0 mmol/l, P = 0.02). In contrast, albuminuria was associated with elevated cholesterol, triglyceride, LDL, and apoB and with diminished LDL particle size. No disturbances in HDL and related lipoproteins were noted. In normoalbuminuric patients, CVD was not associated with any significant changes in lipids. CVD in macroalbuminuric patients was associated with increased triglyceride level (2.37 vs. 1.07 mmol/l, P = 0.001; P = 0.02 for CVD/albuminuria interaction) and LDL cholesterol (5.4 vs. 3.3 mmol/l, P = 0.005; P = 0.004 for interaction). Independent associations were observed for total cholesterol and for LDL particle size and albuminuria.

CONCLUSIONS

Abnormalities in lipid and lipoprotein disturbances are more closely related to albuminuria than to CVD in patients with type 1 diabetes. Measurement of conventional parameters provide sufficient risk information. ApoB and LDL particle size offer limited extra information. HDL metabolism remains undisturbed in the presence of complications. These changes reflect associations with glycemic control, which is the key to understanding lipid and lipoprotein disturbances.

The metabolic syndrome influences the risk of chronic complications in patients with type II diabetes

AIMS/HYPOTHESIS

We examined features of the metabolic syndrome to see if they modified the risk of chronic diabetic complications in patients with Type II (non-insulin-dependent) diabetes mellitus.

METHODS

A total of 85 randomly selected patients with the metabolic syndrome (WHO definition) were compared with 85 Type II diabetic patients matched for age, sex, duration of diabetes, glycaemic control and without the syndrome to assess the microvascular and macrovascular complications.

RESULTS

The patients with the metabolic syndrome had a higher prevalence of cardiovascular disease (52 vs 21%, p < 0.001), microalbuminuria or macroalbuminuria (23 vs 7%, p = 0.003) and distal neuropathy (16 vs 6%, p = 0.048) than patients without the syndrome. The patients with the metabolic syndrome had smaller LDL particle size (25.4+/-1.4 vs 26.4+/-1.1 nm; p < 0.001), which correlated with the ratio of serum triglycerides to HDL cholesterol (r = -0.64, p < 0.001). In a multiple logistic regression analysis the metabolic syndrome was associated with coronary heart disease (RR 3.84, p < 0.001) and microalbuminuria (RR 3.99, p = 0.01). Small LDL particle size was independently associated with neuropathy (RR 0.58; p = 0.04), whereas a high HbA1c was related to neuropathy (RR 1.69, p = 0.04), retinopathy (RR 1.53, p = 0.002) and microalbuminuria (RR 1.54, p = 0.01).

CONCLUSION/INTERPRETATION

Although chronic hyperglycaemia is the main predictor of microvascular complications in patients with Type II diabetes, this risk is modified by some of the components of the metabolic syndrome.

Serum C3 but not plasma acylation-stimulating protein is elevated in Finnish patients with familial combined hyperlipidemia

A trapping defect of fatty acids due to impaired function of acylation-stimulating protein (ASP) has been suggested as one mechanism underlying the metabolic abnormalities in familial combined hyperlipidemia (FCHL). The study aimed at defining the role of ASP and complement C3 in 35 Finnish FCHL families. There was no difference in plasma ASP levels between the 66 hypertriglyceridemic FCHL patients and their 84 normotriglyceridemic relatives. No response in plasma ASP could be observed after a fatty meal in 10 FCHL patients or in 10 control subjects. In familial correlation analyses, C3 exhibited a significant sibling-sibling correlation. The FCHL patients had higher serum C3 levels than their unaffected relatives (P<0.001). Furthermore, serum C3 levels correlated significantly with several lipid parameters. The correlations between ASP and lipid variables were weaker than those of C3. These analyses suggest that common genes might contribute to the regulation of serum C3, triglycerides, HDL-C, free fatty acids, and insulin. The present data do not support the hypothesis that defects of the ASP pathway are reflected in plasma lipoproteins or in impaired plasma lipid clearance postprandially.

Remnant-like lipoprotein particle cholesterol concentration and progression of coronary and vein-graft atherosclerosis in response to gemfibrozil treatment

Remnant lipoproteins such as chylomicron and very low density lipoprotein (VLDL) remnants have been implicated in the progression of coronary atherosclerosis. Recently, a novel method for the determination of the remnant-like lipoprotein particle cholesterol (RLP-C) concentration was developed based on immunoaffinity-separation of plasma. The compositional characteristics of RLP are strikingly similar to those of postprandially modified VLDL. In addition, the method also detects chylomicron remnants. We investigated the relationship between the plasma RLP-C concentration and the angiographic outcome of the 2-year, randomised, placebo-controlled Lipid Coronary Angiography Trial (LOCAT), which used gemfibrozil as lipid lowering agent. The RLP-C response to gemfibrozil treatment has not been described before. Gemfibrozil reduced the median RLP-C concentration by 34%. The on-treatment RLP-C concentration was significantly associated with the progression of the minimum lumen diameter (MLD) (P<0.004). The plasma levels of RLP-C as well as the change in response to treatment was closely associated with plasma triglycerides and the association between on-treatment RLP-C concentration and progression of MLD was not independent of plasma triglycerides. A significant relation was seen between RLP-C and the occurrence of new lesions in vein grafts. Subjects with one new lesion had an approximately 25% higher on-treatment RLP-C concentration and the four patients showing two new lesions had a 100% higher RLP-C concentration than patients without vein graft stenosis. A total of 19 out of 23 subjects having one new lesion, and all four patients showing two new lesions, were assigned to the placebo group. We conclude that the RLP-C concentration, which is likely to reflect the plasma cholesterol contained in postprandially modified VLDL and chylomicron remnants, is strongly associated with angiographically verified progression of focal coronary atherosclerosis, and that lowering of RLPs prevents vein graft stenosis.