Lipoprotein(a), type 2 diabetes and vascular risk in coronary patients

Precision prognostics for cardiovascular disease in Type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Precision medicine has the potential to improve cardiovascular disease (CVD) risk prediction in individuals with Type 2 diabetes (T2D).

METHODS

We conducted a systematic review and meta-analysis of longitudinal studies to identify potentially novel prognostic factors that may improve CVD risk prediction in T2D. Out of 9380 studies identified, 416 studies met inclusion criteria. Outcomes were reported for 321 biomarker studies, 48 genetic marker studies, and 47 risk score/model studies.

RESULTS

Out of all evaluated biomarkers, only 13 showed improvement in prediction performance. Results of pooled meta-analyses, non-pooled analyses, and assessments of improvement in prediction performance and risk of bias, yielded the highest predictive utility for N-terminal pro b-type natriuretic peptide (NT-proBNP) (high-evidence), troponin-T (TnT) (moderate-evidence), triglyceride-glucose (TyG) index (moderate-evidence), Genetic Risk Score for Coronary Heart Disease (GRS-CHD) (moderate-evidence); moderate predictive utility for coronary computed tomography angiography (low-evidence), single-photon emission computed tomography (low-evidence), pulse wave velocity (moderate-evidence); and low predictive utility for C-reactive protein (moderate-evidence), coronary artery calcium score (low-evidence), galectin-3 (low-evidence), troponin-I (low-evidence), carotid plaque (low-evidence), and growth differentiation factor-15 (low-evidence). Risk scores showed modest discrimination, with lower performance in populations different from the original development cohort.

CONCLUSIONS

Despite high interest in this topic, very few studies conducted rigorous analyses to demonstrate incremental predictive utility beyond established CVD risk factors for T2D. The most promising markers identified were NT-proBNP, TnT, TyG and GRS-CHD, with the highest strength of evidence for NT-proBNP. Further research is needed to determine their clinical utility in risk stratification and management of CVD in T2D.

Precision Prognostics for Cardiovascular Disease in Type 2 Diabetes: A Systematic Review and Meta-analysis

Background Precision medicine has the potential to improve cardiovascular disease (CVD) risk prediction in individuals with type 2 diabetes (T2D). Methods We conducted a systematic review and meta-analysis of longitudinal studies to identify potentially novel prognostic factors that may improve CVD risk prediction in T2D. Out of 9380 studies identified, 416 studies met inclusion criteria. Outcomes were reported for 321 biomarker studies, 48 genetic marker studies, and 47 risk score/model studies. Results Out of all evaluated biomarkers, only 13 showed improvement in prediction performance. Results of pooled meta-analyses, non-pooled analyses, and assessments of improvement in prediction performance and risk of bias, yielded the highest predictive utility for N-terminal pro b-type natriuretic peptide (NT-proBNP) (high-evidence), troponin-T (TnT) (moderate-evidence), triglyceride-glucose (TyG) index (moderate-evidence), Genetic Risk Score for Coronary Heart Disease (GRS-CHD) (moderate-evidence); moderate predictive utility for coronary computed tomography angiography (low-evidence), single-photon emission computed tomography (low-evidence), pulse wave velocity (moderate-evidence); and low predictive utility for C-reactive protein (moderate-evidence), coronary artery calcium score (low-evidence), galectin-3 (low-evidence), troponin-I (low-evidence), carotid plaque (low-evidence), and growth differentiation factor-15 (low-evidence). Risk scores showed modest discrimination, with lower performance in populations different from the original development cohort. Conclusions Despite high interest in this topic, very few studies conducted rigorous analyses to demonstrate incremental predictive utility beyond established CVD risk factors for T2D. The most promising markers identified were NT-proBNP, TnT, TyG and GRS-CHD, with the highest strength of evidence for NT-proBNP. Further research is needed to determine their clinical utility in risk stratification and management of CVD in T2D.

Lipoprotein(a) and the Risk for Recurrent Atherosclerotic Cardiovascular Events Among Adults With CKD: The Chronic Renal Insufficiency Cohort (CRIC) Study

Rationale & Objective

Many adults with chronic kidney disease (CKD) and atherosclerotic cardiovascular disease (ASCVD) have high lipoprotein(a) levels. It is unclear whether high lipoprotein(a) levels confer an increased risk for recurrent ASCVD events in this population. We estimated the risk for recurrent ASCVD events associated with lipoprotein(a) in adults with CKD and prevalent ASCVD.

Study Design

Observational cohort study.

Setting & Participants

We included 1,439 adults with CKD and prevalent ASCVD not on dialysis enrolled in the Chronic Renal Insufficiency Cohort study between 2003 and 2008.

Exposure

Baseline lipoprotein(a) mass concentration, measured using a latex-enhanced immunoturbidimetric assay.

Outcomes

Recurrent ASCVD events (primary outcome), kidney failure, and death (exploratory outcomes) through 2019.

Analytical Approach

We used Cox proportional-hazards regression models to estimate adjusted HR (aHRs) and 95% CIs.

Results

Among participants included in the current analysis (mean age 61.6 years, median lipoprotein(a) 29.4 mg/dL [25th-75th percentiles 9.9-70.9 mg/dL]), 641 had a recurrent ASCVD event, 510 developed kidney failure, and 845 died over a median follow-up of 6.6 years. The aHR for ASCVD events associated with 1 standard deviation (SD) higher log-transformed lipoprotein(a) was 1.04 (95% CI, 0.95-1.15). In subgroup analyses, 1 SD higher log-lipoprotein(a) was associated with an increased risk for ASCVD events in participants without diabetes (aHR, 1.23; 95% CI, 1.02-1.48), but there was no evidence of an association among those with diabetes (aHR, 0.99; 95% CI, 0.88-1.10, P comparing aHRs = 0.031). The aHR associated with 1 SD higher log-lipoprotein(a) in the overall study population was 1.16 (95% CI, 1.04-1.28) for kidney failure and 1.02 (95% CI, 0.94-1.11) for death.

Limitations

Lipoprotein(a) was not available in molar concentration.

Conclusions

Lipoprotein(a) was not associated with the risk for recurrent ASCVD events in adults with CKD, although it was associated with a risk for kidney failure.

Lipoprotein(a) levels and risk of adverse events after myocardial infarction in patients with and without diabetes

Introduction: The aim of this study was to evaluate the association of lipoprotein(a) [Lp(a)] levels with long-term outcome in patients with recent history of myocardial infarction (MI), and to investigate if diabetes may influence this association.

Methods: Consecutive MI patients who underwent urgent/emergent coronary angiography from February 2013 to June 2019 were prospectively collected. The primary outcome was the composite of MI recurrence and all-cause death. The propensity score weighting technique was used to account for covariates potentially influencing the relationship between Lp(a) levels and the study outcomes.

Results: The study population consisted of 1018 post-MI patients (median age 63 years). Diabetes was reported in 280 patients (27.5%), who showed lower Lp(a) levels than patients without diabetes (p = 0.026). At a median follow-up of 1121 days, the primary outcome was reported in 182 patients (17.9%). At univariable Cox regression analysis, Lp(a) was associated with the risk of the primary outcome in the overall population and in non-diabetic patients, but not in diabetics. The adjusted Cox regression analysis confirmed the independent association between Lp(a) values and the primary outcome in non-diabetic patients, but not in diabetics.

Lp(a) levels > 70 mg/dL were independently associated with the risk of the primary outcome in non-diabetic patients (adjusted HR: 2.839; 95% CI, 1.382–5.832), but not in diabetics.

Conclusions: In this real-world post-MI population, increasing Lp(a) levels were significantly associated with the risk of recurrent MI and all-cause death, and very high Lp(a) serum concentration independently predicted long-term outcome in non-diabetic patients, but not in diabetics.

Elevated levels of apolipoprotein D predict poor outcome in patients with suspected or established coronary artery disease

BACKGROUND AND AIMS

Apolipoprotein D (apoD) is a lipocalin exerting neuroprotective effects. However, the relevance of apoD in respect to cardiovascular risk is largely unexplored. Therefore, this study aimed to evaluate the ability of apoD to predict future all-cause mortality, cardiovascular mortality, and cardiovascular events.

METHODS

Serum apoD levels were measured in a cohort of 531 Caucasian individuals who underwent coronary angiography (356 males, 175 females; mean age 65 ± 10 years). Fatal and non-fatal events were recorded over a median follow-up period of 5.8 years.

RESULTS

ApoD concentrations at baseline correlated significantly with age, presence of the metabolic syndrome, body mass index, lipoprotein levels, fasting glucose, and estimated glomerular filtration rate. Kaplan-Meier curve analyses by gender-stratified quartiles of apoD revealed that the cumulative incidence rates of mortality and cardiovascular events become higher with increasing apoD levels. The adjusted hazard ratios for participants in the highest quartile of apoD compared to those in the lowest quartile were 4.00 (95% confidence interval [CI] 1.49-10.74) for overall mortality, 5.47 (95% CI 1.20-25.00) for cardiovascular mortality, and 2.52 (95% CI 1.28-5.00) for cardiovascular events.

CONCLUSIONS

High circulating levels of apoD are an indicator of poor prognosis in patients with suspected or established coronary artery disease.

Downhill hiking improves low-grade inflammation, triglycerides, body weight and glucose tolerance

Exercise is a well-established tool for cardiovascular risk reduction. Particularly eccentric exercise, which essentially means walking downwards could favour more people becoming physically active. With the present controlled study, we tested the hypothesis that eccentric exercise can improve insulin sensitivity, triglyceride handling, body mass index, glucose tolerance and inflammation. We allocated 127 healthy sedentary individuals to one of two groups: (i) an active group of 102 individuals walking downwards a predefined route three to five times per week over two months, covering a difference in altitude of 540 m; for the upward route a cable car was used, for which adherence was recorded electronically and (ii) a matched control group of 25 individuals who stayed sedentary. Fasting and postprandial metabolic profiles were obtained at baseline and after two months. Compared to baseline, eccentric exercise significantly improved HOMA insulin resistance (1.94 ± 1.65 vs. 1.71 ± 1.36 (µU⁻¹ ml) × ((mmol/l)⁻¹22.5); p = 0.038) and resulted in a decrease in fasting glucose (97 ± 15 vs. 94 ± 9 mg dl⁻¹; p = 0.025) and glucose tolerance (238 ± 50 vs. 217 ± 47 mg dl⁻¹ h⁻¹; p < 0.001), whereas these parameters did not change significantly in the control group. Eccentric exercise significantly improved triglyceride tolerance (1923 ± 1295 vs. 1670 ± 1085 mg dl⁻¹ h⁻¹; p = 0.003), whereas triglyceride tolerance remained unchanged in the control group (p = 0.819). Furthermore, body mass index (27.7 ± 4.3 vs. 27.4 ± 4.3 kg m⁻²; p = 0.003) and C-reactive protein (0.27 ± 0.42 vs. 0.23 ± 0.25 mg dl⁻¹; p = 0.031) were significantly lowered in the eccentric exercise group but not in the control group. Downhill walking, a type of exercise is a promising unusual exercise modality with favorable effects on body mass index, insulin action, on postprandial glucose and triglyceride handling and on C-reactive protein.

ClinicalTrials.gov Identifier: NCT00386854.

The association between lipoprotein (a) and carotid atherosclerosis in patients with type 2 diabetes without pre-existing cardiovascular disease: A cross-sectional study

AIMS

Lipoprotein (a) [Lp(a)] has been considered a determinant of residual cardiovascular risk. We aimed to investigate associations between serum Lp(a) levels and carotid atherosclerosis.

METHODS

This cross-sectional study included 662 type 2 diabetic patients without cardiovascular disease. The mean value of three right and left measurements was used to indentify increased carotid intima-media thickness (CIMT). A carotid plaque was defined as a focal wall thickening >50% of the surrounding IMT or its CIMT ≥1.5 mm. The presence of carotid atherosclerosis was defined as having CIMT ≥1.0 mm or carotid plaque.

RESULTS

A total of 34.3% of patients had carotid atherosclerosis. The median Lp(a) level was significantly higher in subjects with carotid atherosclerosis (14.6 vs. 10.2 mg/dL, P < 0.001). The log-transformed Lp(a) level per 1-standard deviation increase was significantly associated with higher risk of the presence of carotid atherosclerosis (odds ratio [OR] 1.46; 95% confidence interval [CI] 1.16 - 1.84, P = 0.001) after adjusting other parameters. The log Lp(a) level was still significantly associated with the risk of carotid atherosclerosis in subjects with optimal low-density lipoprotein cholesterol (LDL-C) <100 mg/dL (OR 1.48; 95% CI 1.16 - 1.88, P = 0.001). Higher Lp(a) and LDL-C had an additive effect on the presence of carotid atherosclerosis.

CONCLUSION

Elevated Lp(a) was significantly associated with the presence of carotid atherosclerosis in patients with type 2 diabetes, independent of conventional cardiometabolic risk factors.

Lipoprotein(a) plasma levels are not associated with survival after acute coronary syndromes: An observational cohort study

Background

Lipoprotein(a) [Lp(a)] is associated with coronary artery disease in population studies, however studies on its predictive value in patients with cardiovascular disease, in particular after acute coronary syndromes (ACS), are conflicting. The aim of this study was to investigate whether Lp(a) is associated with survival after ACS.

Methods and results

We analyzed Lp(a) measurement in 1,245 patients who underwent coronary angiography for ACS. The median follow-up for cardiovascular and all-cause mortality was 5.0 (IQR 3.2–8.0) years. 655 (52.6%) presented with ST-segment elevation myocardial infarction (STEMI), 424 (34.1%) with Non-ST-segment elevation myocardial infarction (NSTEMI) and 166 (13.3%) underwent coronary angiography for unstable angina. Cardiovascular mortality was 9.1% and all-cause mortality was 15.7%. Patients were stratified into four groups to their Lp(a) levels. (≤15mg/dL, >15-30mg/dL, >30-60mg/dL, and >60mg/dL). Multivessel disease was significantly more common in patients with Lp(a)>60mg/dL (p<0.05). Increased levels of Lp(a) were not associated with cardiovascular mortality (HR compared with Lp(a) ≤15mg/dL were 1.2, 1.2, and 1.0, respectively; p = 0.69) and not with all-cause mortality (HR compared with Lp(a) ≤15mg/dL were 1.2, 1.2, and 1.2, respectively; p = 0.46).

Conclusions

Lp(a) levels at time of ACS were neither associated with cardiovascular nor with all-cause mortality. Although Lp(a) has been shown to be associated with incidence of coronary artery disease, this study does not support any role of Lp(a) as a risk factor for mortality after ACS. This should be taken into account for development of outcome studies for agents targeting Lp(a) plasma levels.

Lipoprotein(a): An underrecognized genetic risk factor for malignant coronary artery disease in young Indians

Malignant coronary artery disease (CAD) refers to a severe and extensive atherosclerotic process involving multiple coronary arteries in young individuals (aged <45 years in men and <50 years in women) with a low or no burden of established risk factors. Indians, in general, develop acute myocardial infarction (AMI) about 10 years earlier; AMI rates are threefold to fivefold higher in young Indians than in other populations. Although established CAD risk factors have a predictive value, they do not fully account for the excessive burden of CAD in young Indians. Lipoprotein(a) (Lp(a)) is increasingly recognized as the strongest known genetic risk factor for premature CAD, with high levels observed in Indians with malignant CAD. High Lp(a) levels confer a twofold to threefold risk of CAD-a risk similar to that of established risk factors, including diabetes. South Asians have the second highest Lp(a) levels and the highest risk of AMI from the elevated levels, more than double the risk observed in people of European descent. Approximately 25% of Indians and other South Asians have elevated Lp(a) levels (≥50 mg/dl), rendering Lp(a) a risk factor of great importance, similar to or surpassing diabetes. Lp(a) measurement is ready for clinical use and should be an essential part of all CAD research in Indians.

Serum uromodulin is associated with impaired glucose metabolism

Uromodulin is the most abundant urine protein under physiological conditions. It has recently been described as a serum and plasma marker for kidney disease. Whether uromodulin is associated with impaired glucose metabolism is unknown.We therefore measured serum uromodulin and glucose traits in a cohort of 529 consecutively recruited patients.Serum uromodulin was significantly and inversely correlated with fasting plasma glucose (r = -0.161; P < 0.001), with plasma glucose 2 hours after an oral 75 g glucose challenge (r = -0.158; P = 0.001), and with HbA1c (r = -0.103; P = 0.018). A total of 146 (27.6%) of our patients had type 2 diabetes mellitus (T2DM). Analysis of covariance confirmed that T2DM was an independent determinant of serum uromodulin (F = 5.5, P = 0.020) after multivariate adjustment including hypertension and glomerular filtration rate. Prospectively, uromodulin was lowest in patients with T2DM at baseline, higher in initially nondiabetic subjects who developed diabetes during follow-up (FU) and highest among nondiabetic patients (147.7 ± 69.9 vs 164 ± 67 vs 179.9 ± 82.2 ng/mL, Ptrend < 0.001). Similar results were seen with respect to prediabetes (168.0 ± 81.2 vs 172.8 ± 66.3 vs 188.2 ± 74.0 ng/mL, P = 0.011).We conclude that serum uromodulin is significantly associated with impaired glucose metabolism and the development of prediabetes and diabetes.

The relationship between Lp(a) and CVD outcomes: a systematic review

Robust associations between lipoprotein(a) [Lp(a)] and CVD outcomes among general populations have been published in previous studies. However, associations in high risk primary prevention and secondary prevention populations are less well defined. In order to investigate this further, a systematic review was performed including prospective studies, which assessed the relationship between Lp(a) and CVD outcomes using multivariable analyses. Additional information was gathered on Lp(a) assays, multivariable modelling and population characteristics. Literature searches from inception up to December 2015 retrieved 2850 records. From these 60 studies were included. Across 39 primary prevention studies in the general population (hazard ratios ranged from 1.16 to 2.97) and seven high risk primary prevention studies (hazard ratios ranged from 1.01 to 3.7), there was evidence of a statistically significant relationship between increased Lp(a) and an increased risk of future CVD. Results in 14 studies of secondary prevention populations were also suggestive of a modest statistically significant relationship (hazard ratios ranged from 0.75 to 3.7).Therefore current evidence would suggest that increased Lp(a) levels are associated with modest increases in the risk of future CVD events in both general and higher risk populations. However, further studies are required to confirm these findings.

Lipoprotein(a): novel target and emergence of novel therapies to lower cardiovascular disease risk

PURPOSE OF REVIEW

This article summarizes recent observations on the role of lipoprotein(a) [Lp(a)] as a risk factor mediating cardiovascular disease.

RECENT FINDINGS

Lp(a) is a highly prevalent cardiovascular risk factor, with levels above 30 mg/dl affecting 20-30% of the global population. Up until now, no specific therapies have been developed to lower Lp(a) levels. Three major levels of evidence support the notion that elevated Lp(a) levels are a causal, independent, genetic risk factor for cardiovascular disease: epidemiologic studies and meta-analyses, genome-wide association studies and Mendelian randomization studies. Recent studies also have noted that individuals with low levels of Lp(a) are associated with a higher risk of incident type 2 diabetes mellitus, and conversely individuals with high levels have a lower risk, but this association does not appear to be causal. Novel therapies to lower Lp(a) include PCSK9 inhibitors and antisense oligonucleotides directly preventing translation of apolipoprotein(a) mRNA.

SUMMARY

With this robust and expanding clinical database, a reawakening of interest in Lp(a) as clinical risk factor is taking place. Trials are underway with novel drugs that substantially lower Lp(a) and may reduce its contribution to cardiovascular disease.

Lipid parameters in patients with acute coronary syndromes versus stable coronary artery disease

BACKGROUND

Differences in lipid parameters between patients with acute coronary syndromes (ACS) and patients with stable coronary artery disease (CAD) are unclear and are addressed in this study.

METHODS

We enrolled 582 patients with angiographically proven stable CAD (of whom 26·9% had diabetes mellitus type 2 (T2DM)) and 182 patients with ACS (of whom 35·8% had T2DM).

RESULTS

HDL cholesterol and apolipoprotein A1 levels were significantly lower in patients with ACS than in patients with CAD (46 ± 16 mg/dL vs. 50 ± 16 mg/dL, P < 0·001, and 139 ± 30 mg/dL vs. 155 ± 31 mg/dL, P < 0·001, respectively). Analysis of covariance (ancova) adjusting for age, gender, smoking, BMI, statin therapy, alcohol use, hypertension and diabetic state confirmed an independent impact of ACS on HDL cholesterol and apolipoprotein A1 levels (F = 24·1; P < 0·001). In contrast, total cholesterol, LDL cholesterol, non-HDL cholesterol and apolipoprotein B levels did not differ significantly between patients with ACS and patients with stable CAD.

CONCLUSION

HDL cholesterol and apolipoprotein A1 levels are lower in patients with ACS than in patients with stable CAD.

High plasma chemerin is associated with renal dysfunction and predictive for cardiovascular events - Insights from phenotype and genotype characterization

The novel adipokine chemerin, encoded by the RARRES2 gene, has been suggested to be linked to insulin resistance and to the metabolic syndrome (MetS). However, no well-defined cardiovascular profile has been reported and the association with coronary artery disease (CAD) is a matter of debate. Because there is a relation between renal dysfunction and CAD, we analyzed plasma chemerin levels and the estimated glomerular filtration rate (eGFR) in 495 patients undergoing coronary angiography for the evaluation of established or suspected stable CAD. Chemerin levels were higher in patients with Type 2 diabetes mellitus (T2DM, n=111) and the metabolic syndrome (MetS, n=147) than in subjects without T2DM (191.5±72.9 vs. 169.7±64.7ng/ml, p=0.001) or the MetS (201.2±71.0 vs. 163,1ng/ml, p<0.001), but did not differ significantly between patients with significant CAD (n=247) and those without significant CAD (177.1±67.0 vs. 171.7±67.2ng/ml, p=0.193). Analysis of covariance using age, sex, and BMI as covariates showed that chemerin was significantly and independently associated with eGFR (F=49.6, p<0.001). After an 8-year follow-up period, patients with high chemerin levels were more often affected by cardiovascular events (HR=1.72 [95% CI 1.19-2.47], p=0.004), even after appropriate adjustment for age, gender, BMI, as well as eGFR (adjusted HR 1.51 [95% CI 1.03-2.23], p=0.037). Given the cardiometabolic role of chemerin, we also applied a Cardio-Metabo Chip analysis and revealed a genome-wide significant association with SNPs (rs55709438, rs2444030, and rs3098423) located at chromosomal region 15q15-23, which were associated with metabolic traits and eGFR. This study for the first time demonstrates that high chemerin concentrations are significantly associated with renal impairment and predictive of cardiovascular events and that 15q15-23 might have an impact on chemerin levels beyond common genetic variations in RARRES2.

Genome-wide association study reveals a polymorphism in the podocyte receptor RANK for the decline of renal function in coronary patients

Impaired kidney function is a significant health problem and a major concern in clinical routine and is routinely determined by decreased glomerular filtration rate (GFR). In contrast to single assessment of a patients' kidney function providing only limited information on patients' health, serial measurements of GFR clearly improves the validity of diagnosis. The decline of kidney function has recently been reported to be predictive for mortality and vascular events in coronary patients. However, it has not been investigated for genetic association in GWA studies. This study investigates for the first time the association of cardiometabolic polymorphisms with the decline of estimated GFR during a 4 year follow up in 583 coronary patients, using the Cardio-Metabo Chip. We revealed a suggestive association with 3 polymorphisms, surpassing genome-wide significance (p = 4.0 e-7). The top hit rs17069906 (p = 5.6 e-10) is located within the genomic region of RANK, recently demonstrated to be an important player in the adaptive recovery response in podocytes and suggested as a promising therapeutic target in glomerular diseases.

Impact of the albumin to creatinine ratio and the coronary artery state on vascular events

Albuminuria is an important indicator of cardiovascular risk. However, whether albuminuria predicts cardiovascular events independently of the baseline coronary artery state has not yet been investigated. We measured urinary albumin and creatinine concentrations in 867 consecutive patients who underwent coronary angiography for the evaluation of suspected or established stable coronary artery disease (CAD). Albuminuria was defined as a urinary albumin to creatinine ratio of 30 μg/mg or greater. Prospectively, we recorded the vascular events over 3.2 ± 1.2 years. From our patients, 318 had neither albuminuria nor significant CAD (i.e., coronary stenoses ≥ 50%) at baseline angiography, 69 had albuminuria but no significant CAD, 343 did not have albuminuria but significant CAD, and 137 had both albuminuria and significant CAD. Compared with the event rate among patients with neither albuminuria nor significant CAD (8.2%), event rates were significantly higher in patients with albuminuria without significant CAD (18.8%; p = 0.002) and in normoalbuminuric patients with significant CAD (19.2%; p <0.001); it was highest in patients with both albuminuria and significant CAD (33.6%; p <0.001). Importantly, event rates were similar in patients with albuminuria free of significant CAD and those with significant CAD but normoalbuminuria (p = 0.767). In conclusion, this is the first study demonstrating that albuminuria per se is a CAD risk equivalent after adjusting for the angiographically proven atherosclerotic state at baseline.

The association between circulating lipoprotein(a) and type 2 diabetes: is it causal?

Epidemiological evidence supports a direct and causal association between lipoprotein(a) [Lp(a)] levels and coronary risk, but the nature of the association between Lp(a) levels and risk of type 2 diabetes (T2D) is unclear. In this study, we assessed the association of Lp(a) levels with risk of incident T2D and tested whether Lp(a) levels are causally linked to T2D. We analyzed data on 18,490 participants from the European Prospective Investigation of Cancer (EPIC)-Norfolk cohort that included adults aged 40-79 years at baseline 1993-1997. During an average 10 years of follow-up, 593 participants developed incident T2D. Cox regression models were used to estimate the association between Lp(a) levels and T2D. In Mendelian randomization analyses, based on EPIC-Norfolk combined with DIAbetes Genetics Replication And Meta-analysis data involving a total of 10,088 diabetes case participants and 68,346 control participants, we used a genetic variant (rs10455872) as an instrument to test whether the association between Lp(a) levels and T2D is causal. In adjusted analyses, there was an inverse association between Lp(a) levels and T2D: hazard ratio was 0.63 (95% CI 0.49-0.81; P trend = 0.003) comparing the top versus bottom quintile of Lp(a). In EPIC-Norfolk, a 1-SD increase in logLp(a) was associated with a lower risk of T2D (odds ratio [OR] 0.88 [95% CI: 0.80-0.95]). However, in Mendelian randomization analyses, a 1-SD increase in logLp(a) due to rs10455872, which explained 26.8% of the variability in Lp(a) levels, was not associated with risk of T2D (OR 1.03 [0.96-1.10]; P = 0.41). These prospective findings demonstrate a strong inverse association of Lp(a) levels with risk of T2D. However, a genetic variant that elevated Lp(a) levels was not associated with risk of T2D, suggesting that elevated Lp(a) levels are not causally associated with a lower risk of T2D.

Lipoprotein(a) for risk assessment in patients with established coronary artery disease

OBJECTIVES

The purpose of this study was to assess the prognostic utility of lipoprotein(a) [Lp(a)] in individuals with coronary artery disease (CAD).

BACKGROUND

Data regarding an association between Lp(a) and cardiovascular (CV) risk in secondary prevention populations are sparse.

METHODS

Plasma Lp(a) was measured in 6,708 subjects with CAD from 3 studies; data were then combined with 8 previously published studies for a total of 18,978 subjects.

RESULTS

Across the 3 studies, increasing levels of Lp(a) were not associated with the risk of CV events when modeled as a continuous variable (odds ratio [OR]: 1.03 per log-transformed SD, 95% confidence interval [CI]: 0.96 to 1.11) or by quintile (Q5:Q1 OR: 1.05, 95% CI: 0.83 to 1.34). When data were combined with previously published studies of Lp(a) in secondary prevention, subjects with Lp(a) levels in the highest quantile were at increased risk of CV events (OR: 1.40, 95% CI: 1.15 to 1.71), but with significant between-study heterogeneity (p = 0.001). When stratified on the basis of low-density lipoprotein (LDL) cholesterol, the association between Lp(a) and CV events was significant in studies in which average LDL cholesterol was ≥130 mg/dl (OR: 1.46, 95% CI: 1.23 to 1.73, p < 0.001), whereas this relationship did not achieve statistical significance for studies with an average LDL cholesterol <130 mg/dl (OR: 1.20, 95% CI: 0.90 to 1.60, p = 0.21).

CONCLUSIONS

Lp(a) is significantly associated with the risk of CV events in patients with established CAD; however, there exists marked heterogeneity across trials. In particular, the prognostic value of Lp(a) in patients with low cholesterol levels remains unclear.

Insulin resistance is significantly associated with the metabolic syndrome, but not with sonographically proven peripheral arterial disease

Objective

Insulin resistance (IR) is the key feature of the metabolic syndrome (MetS); its association with peripheral arterial disease (PAD) is unclear. We hypothesized that IR is associated with both the MetS and sonographically proven PAD.

Methods

IR was determined by the Homeostasis Model Assessment (HOMA) index in 214 patients with sonographically proven PAD as well as in 197 controls, who did not have a history of PAD and in whom coronary artery disease was ruled out angiographically; the MetS was defined according to NCEP-ATPIII criteria.

Results

HOMA IR scores were significantly higher in MetS patients than in subjects without the MetS (5.9 ± 6.2 vs. 2.9 ± 3.9; p <0.001). However, HOMA IR did not differ significantly between patients with PAD and controls (4.2 ± 5.4 vs. 3.3 ± 4.3; p = 0.124). When both, the presence of MetS and of PAD were considered, HOMA IR was significantly higher in patients with the MetS both among those with PAD (6.1 ± 5.7 vs. 3.6 ± 5.2; p<0.001) and among controls (5.8 ± 6.8 vs. 2.3 ± 1.8; p <0.001), whereas it did not differ significantly between patients with PAD and controls among patients with the MetS (5.8 ± 6.8 vs. 6.1 ± 5.7; p = 0.587) nor among those without the MetS (2.3 ± 1.8 vs. 3.6 ± 5.2; p = 0.165). Similar results were obtained with the International Diabetes Federation definition of the MetS.

Conclusion

IR is significantly associated with the MetS but not with sonographically proven PAD.

Elevated fasting glucose levels within normal range are associated with an increased risk of metabolic syndrome in older women

OBJECTIVE

The prevalence of cardiovascular disease (CVD) and metabolic syndrome (MetS) increases with increasing fasting plasma glucose (FPG) levels in an elderly population with pre-diabetes or diabetes. However, it remains unknown whether the relationship between elevated FPG and increased risks of MetS exists in older women with normoglycemia (FPG<100mg/dL). Therefore, the present study was conducted to fill the lack of information in that area.

MATERIALS AND METHODS

We included 6505 apparently healthy women, aged 65years and older, with normoglycemia who participated in routine health checkups at health screening centers in Taiwan. Components of MetS (FPG, waist circumference (WC), high-density lipoprotein cholesterol (HDL-C), triglycerides, and systolic/diastolic blood pressure), body mass index (BMI), low-density lipoprotein cholesterol (LDL-C), total cholesterol, and percentage body fat (PBF) were examined in all subjects.

RESULTS

Subjects were sub-grouped by FPG levels (<90mg/dL, 91-95mg/dL and >95mg/dL for group 1, group 2 and group 3, respectively). Subjects in group 2 and group 3 were 1.22-fold (P=0.017) and 1.25-fold (P=0.007) more likely to have MetS compared with those in group 1. Age, WC, BMI, PBF, systolic and diastolic blood pressure, total cholesterol, triglycerides, and HDL-C were significantly correlated with FPG, whereas HDL-C was negatively correlated with FPG. In a multivariate stepwise regression analysis, PBF, LDL-C, triglycerides, and age were significantly and independently associated with FPG.

CONCLUSION

Among older women, the risk of MetS was significantly associated with elevated FPG even for subjects with normal FPG. Lifestyle interventions for reducing PBF and controlling dyslipidemia could help reduce the risk of MetS in this population.

Lipoprotein(a) and cardiovascular disease in diabetic patients

Lipoprotein(a) (Lp[a]) is a LDL-like particle consisting of an ApoA moiety linked to one molecule of ApoB(100). Recent data from large-scale prospective studies and genetic association studies provide highly suggestive evidence for a potentially causal role of Lp(a) in affecting risk of cardiovascular disease (CVD) in general populations. Patients with Type 2 diabetes display clustered metabolic abnormalities and elevated risk of CVD. Lower plasma Lp(a) levels were observed in diabetic patients in several recent studies. Epidemiology studies of Lp(a) and CVD risk in diabetic patients generated inconsistent results. We recently found that Lp(a)-related genetic markers did not predict CVD in two diabetic cohorts. The current data suggest that Lp(a) may differentially affect cardiovascular risk in diabetic patients and in the general population. More prospective studies, Mendelian randomization analysis and functional studies are needed to clarify the causal relationship of Lp(a) and CVD in diabetic patients.

Genetic variants, plasma lipoprotein(a) levels, and risk of cardiovascular morbidity and mortality among two prospective cohorts of type 2 diabetes

AIMS

To examine the relations between genetic loci, plasma lipoprotein(a) [Lp(a)] levels, and cardiovascular disease (CVD) risk among diabetic patients and compare with the observations in the general population.

METHODS AND RESULTS

In two prospective cohorts of patients with type 2 diabetes (n= 2308) from the Nurses' Health Study and the Health Professional Follow-Up Study, we performed (i) genome-wide association (GWA) scans for plasma Lp(a); (ii) prospective analysis of plasma Lp(a) for CVD risk and mortality; and (iii) genetic association analysis for CVD risk and mortality. Meta-analysis of the two GWA scans yielded 71 single-nucleotide polymorphisms (SNPs) on chromosome 6q associated with plasma Lp(a) levels at a genome-wide significance level (P< 5 × 10(-8)). The SNP rs10455872 in LPA was most strongly associated with Lp(a) (P= 4.60 × 10(-39)). Forward-selection analysis indicated that rs10455872 and other five SNPs in a region encompassing LPA, PLG, SLC22A3, and LPAL2 genes were independently associated with Lp(a) levels and jointly explained ∼20% of variation in diabetic patients. In prospective analysis, we did not find any significant association between plasma levels and CVD incidence; the relative risk for coronary heart disease (CHD), CVD, and CVD death was 1.05 [95% confidence interval (CI): 0.95-1.15], 1.05 (0.96-1.15), and 1.21 (0.99-1.47) per 1-SD higher log-transformed Lp(a) levels, respectively. Consistently, none of the Lp(a) SNPs were associated with CVD risk or mortality (all P> 0.09). For the best SNP rs10455872 for plasma Lp(a) levels, the OR for CHD, CVD, and CVD death was 0.94 (95% CI: 0.69-1.28), 0.97 (0.72-1.29), and 1.23 (0.79-1.92), respectively. The genetic effect on CHD risk showed a significant heterogeneity between the diabetic and the general populations (P= 0.006).

CONCLUSION

Our data indicate that the effect of Lp(a) on CVD risk among diabetic patients might be different from that in the general population. Diabetes status may attenuate the relation between Lp(a) and cardiovascular risk.

Relation of albuminuria to angiographically determined coronary arterial narrowing in patients with and without type 2 diabetes mellitus and stable or suspected coronary artery disease

Albuminuria is associated with atherothrombotic events and all-cause mortality in patients with and without diabetes. However, it is not known whether albuminuria is associated with atherosclerosis per se in the same manner. The present study included 914 consecutive white patients who had been referred for coronary angiography for the evaluation of established or suspected stable coronary artery disease (CAD). Albuminuria was defined as a urinary albumin/creatinine ratio ≥ 30 μg/mg. Microalbuminuria was defined as 30 to 300 μg albumin/mg creatinine, and macroalbuminuria as a urinary albumin/creatinine ratio of ≥ 300 μg/mg. The prevalence of stenoses of ≥ 50% was significantly greater in patients with albuminuria than in those with normoalbuminuria (66% vs 51%; p <0.001). Logistic regression analysis, adjusted for age, gender, diabetes, smoking, hypertension, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, C-reactive protein, body mass index, estimated glomerular filtration rate, and the use of angiotensin-converting enzyme inhibitors/angiotensin II antagonists, aspirin, and statins, confirmed that albuminuria was significantly associated with stenoses ≥ 50% (standardized adjusted odds ratio [OR] 1.68, 95% confidence interval [CI] 1.15 to 2.44; p = 0.007). The adjusted OR was 1.54 (95% CI 1.03 to 2.30; p = 0.034) for microalbuminuria and 2.55 (95% CI 1.14 to 5.72; p = 0.023) for macroalbuminuria. This association was significant in the subgroup of patients with type 2 diabetes (OR 1.66, 95% CI 1.01 to 2.74; p = 0.045) and in those without diabetes (OR 1.42, 95% CI 1.05 to 1.92; p = 0.023). An interaction term urinary albumin/creatinine ratio*diabetes was not significant (p = 0.579). In conclusion, micro- and macroalbuminuria were strongly associated with angiographically determined coronary atherosclerosis in both patients with and those without type 2 diabetes mellitus, independent of conventional cardiovascular risk factors and the estimated glomerular filtration rate.

Insulin resistance is associated with the metabolic syndrome and is not directly linked to coronary artery disease

BACKGROUND

Insulin resistance (IR) is the key feature of the metabolic syndrome (MetS). Its association with directly visualized coronary atherosclerosis is unclear. We hypothesised that insulin resistance is associated with both angiographically determined coronary artery disease (CAD) and with the MetS.

METHODS

In 986 consecutive patients undergoing coronary angiography for the evaluation CAD, IR was determined by the HOMA index; the MetS was defined according to NCEP-ATPIII criteria; and significant CAD was diagnosed when coronary stenoses ≥50% were present.

RESULTS

HOMA IR scores were higher in MetS patients than in subjects without the MetS (4.9±6.4 vs. 2.2±2.0; p<0.001). HOMA IR did not differ significantly between patients with significant CAD and those who did not have significant CAD. When both, the presence of MetS and of significant CAD were considered, HOMA IR was significantly higher in patients with the MetS both among those who had significant CAD (4.9±6.8 vs. 2.2±1.8; p<0.001) and among those who did not have significant CAD (5.0±5.8 vs. 2.1±2.3; p<0.001), it did not differ significantly between patients with significant CAD and subjects without significant CAD among patients with the MetS nor among those without MetS. Similar results were obtained with the IDF definition of the MetS.

CONCLUSION

IR is significantly associated with the MetS but not with angiographically determined CAD. IR may play a greater role in the eventual precipitation of thrombosis than in the gradual progression of atherosclerosis.

Low bone mineral density is not associated with angiographically determined coronary atherosclerosis in men

This study for the first time investigates the association of bone mineral density (BMD) with angiographically determined coronary atherosclerosis in men. Our data show that the prevalence of low BMD is very high in men undergoing coronary angiography. However, neither osteopenia nor osteoporosis is associated with an increased prevalence of angiographically determined coronary atherosclerosis.

INTRODUCTION

The association of low BMD with angiographically determined coronary atherosclerosis in men is unknown.

METHODS

We enrolled 623 consecutive men undergoing coronary angiography for the evaluation of established or suspected coronary artery disease (CAD). BMD was assessed by dual X-ray absorptiometry. CAD was diagnosed in the presence of any coronary artery lumen narrowing at angiography; coronary stenoses with lumen narrowing > or =50% were considered significant.

RESULTS

From the total study cohort (mean age of 64 +/- 11 years), 207 patients (33.2%) had osteopenia and 65 (10.4%) had osteoporosis; at angiography, CAD was diagnosed in 558 patients (89.6%) and 403 (64.7%) had significant coronary stenoses. In multivariate logistic regression analysis neither osteopenia nor osteoporosis was associated with an increased prevalence of CAD (adjusted odds ratios (ORs) = 0.71 [95% confidence interval 0.40-1.23]; p = 0.222 and 1.03 [0.38-2.80]; p = 0.955, respectively) or with significant coronary stenoses (OR 0.74 [0.52-1.07], p = 0.112 and 0.72 [0.41-1.26]; p = 0.251, respectively). Also, as a continuous variable, BMD was not associated with angiographically diagnosed CAD.

CONCLUSIONS

The prevalence of low BMD is very high in men undergoing coronary angiography. However, low BMD is not associated with angiographically determined coronary atherosclerosis in men.

Oxidized LDL, lipoprotein (a) and other emergent risk factors in acute myocardial infarction (FORTIAM study)

INTRODUCTION AND OBJECTIVES

To determine the prevalence of acute myocardial infarction (AMI) without classical risk factors, and to ascertain whether affected patients exhibit a higher prevalence of emergent risk factors and whether the presence of specific emergent risk factors influence prognosis at 6 months.

METHODS

The FORTIAM (Factores Ocultos de Riesgo Tras un Infarto Agudo de Miocardio) study is a multicenter cohort study that includes 1371 AMI patients who were admitted within 24 hours of symptom onset. Strict definitions were used for classical risk factors and the concentrations of the following markers were determined: lipoprotein (a) [Lp(a)], oxidized low-density lipoprotein (oxLDL), high-sensitivity C-reactive protein, fibrinogen, homocysteine and antibody to Chlamydia. The end-points observed during the 6-month follow-up were death, angina and re-infarction.

RESULTS

The prevalence of AMI without classical risk factors was 8.0%. The absence of classical risk factors did not affect the 6-month prognosis. The only emergent risk factors independently associated with a poorer prognosis were the Lp(a) and oxLDL concentrations. Cut-points were determined using smoothing splines: 60 mg/ dL for Lp(a) and 74 U/L for oxLDL. The associated hazard ratios, adjusted for age, sex and classical risk factors, were 1.40 (95% confidence interval, 1.06-1.84 ) and 1.48 (95% confidence interval, 1.06-2.06), respectively.

CONCLUSIONS

The proportion of AMI patients without classical risk factors was low and their prognosis was similar to that in other AMI patients. Both oxLDL and Lp(a) concentrations were independently associated with a poorer 6-month prognosis, irrespective of the presence of classical risk factors.

Low serum LDL cholesterol in patients with type 2 diabetes: an analysis on two different patient populations

BACKGROUND

Patients with type 2 diabetes (T2DM) typically exhibit a pattern of dyslipidemia with high triglycerides, low HDL cholesterol, and small LDL particles. We aimed at investigating whether also LDL cholesterol levels are altered in diabetic patients.

METHODS

Lipid panels were obtained in a consecutive series of angiographied coronary patients (n=750), and in a large sample of hypertensive outpatients (n=5949).

RESULTS

T2DM patients in the cohort of coronary patients (n=164; 21.9%) had significantly higher triglycerides (203±138 vs. 153±91 mg/dl; p<0.001), lower HDL cholesterol (44±14 vs. 50±14 mg/dl; p<0.001), lower apolipoprotein A1 (140±28 vs. 148±28 mg/dl; p=0.002), lower total cholesterol (211±48 vs. 220±42 mg/dl; p=0.006) and, importantly, lower LDL cholesterol (122±38 vs. 134±35 mg/dl; p<0.001) than non-diabetic subjects. Whereas apolipoprotein B was similar in T2DM patients as in non-diabetic subjects (113±26 vs. 114±25 mg/dl; p=0.648), the LDL cholesterol/apolipoprotein B ratio was significantly lower (1.08±0.24 vs. 1.18±0.21; p<0.001) and LDL particles were significantly smaller (257±7 vs. 259±6 Å; p<0.001) in T2DM patients. Also among the hypertensive subjects, diabetic patients (n=1632; 27.3%) besides higher triglycerides (173±70 vs. 151±65 mg/dl; p<0.001) and lower HDL cholesterol (53±17 vs. 57±19 mg/dl; p<0.001) exhibited lower total cholesterol (216±44 vs. 222±41 mg/dl; p<0.001) and lower LDL cholesterol (127±40 vs. 136±37 mg/dl; p<0.001) than non-diabetic subjects.

CONCLUSIONS

Both among angiographied coronary patients and hypertensive outpatients, LDL cholesterol is significantly lower in T2DM patients than in non-diabetic individuals.

Predictive value of the decrease in circulating dendritic cell precursors in stable coronary artery disease

DCs (dendritic cells) are present in atherosclerotic lesions leading to vascular inflammation, and the number of vascular DCs increases during atherosclerosis. Previously, we have shown that the levels of circulating DCPs (DC precursors) are reduced in acute coronary syndromes through vascular recruitment. In the present study, we have investigated whether DCP levels are also reduced in stable CAD (coronary artery disease). The levels of circulating mDCPs (myeloid DCPs), pDCPs (plasmacytoid DCPs) and tDCP (total DCPs) were investigated using flow cytometry in 290 patients with suspected stable CAD. A coronary angiogram was used to evaluate a CAD score for each patient as follows: (i) CAD excluded (n=57); (ii) early CAD (n=63); (iii) moderate CAD (n=85); and (iv) advanced CAD (n=85). Compared with controls, patients with advanced stable CAD had lower HDL (high-density lipoprotein)-cholesterol (P=0.03) and higher creatinine (P=0.003). In advanced CAD, a significant decrease in circulating mDCPs, pDCPs and tDCPs was observed (each P<0.001). A significant inverse correlation was observed between the CAD score and mDCPs, pDCPs or tDCPs (each P<0.001). Patients who required percutaneous coronary intervention or coronary artery bypass grafting had less circulating mDCPs, pDCPs and tDCPs than controls (each P<0.001). Multiple stepwise logistic regression analysis suggested mDCPs, pDCPs and tDCPs as independent predictors of CAD. In conclusion, we have shown that patients with stable CAD have significantly lower levels of circulating DCPs than healthy individuals. Their decrease appears to be an independent predictor of the presence of, and subsequent therapeutic procedure in, stable CAD.

Interactions of lipoprotein(a) with diabetes mellitus, apolipoprotein B and cholesterol enhance the prognostic values for coronary artery disease

BACKGROUND

Synergistic interactions between elevated serum lipoprotein(a) [Lp(a)] and other unfavorable risk factors have been proposed to cause very high risk for coronary artery disease (CAD). The aim of this study was to examine the potential interactions between Lp(a) and other risk factors.

METHODS

The profiles of serum (apo)(lipo)proteins, markers of inflammation, indicators of hemoconcentration as well as classical risk factors were determined in 264 clinically stable angiographically documented subjects. Correlation, linear and logistic regression and stratification analyses were performed.

RESULTS

The frequency and severity of CAD and the prevalence of diabetes mellitus were significantly higher in the 3rd relative to 1st tertile of Lp(a). Subjects with Lp(a) levels in the upper tertile had significantly higher levels of serum glucose, total cholesterol and low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB), calcium, phosphate and their ion product. Bivariate correlation analysis indicated that serum Lp(a) was associated positively with the occurrence and severity of CAD, diabetes mellitus and the levels of serum glucose, cholesterol, LDL-C, apoB, calcium, phosphate and inversely to physical inactivity. In linear regression analysis, LDL-C (or apoB), diabetes, physical inactivity and phosphate were the major independent determinants of Lp(a) values. In multiple logistic regression analysis, after adjusting for major risk factors, Lp(a) showed a significant and independent association with the prevalence of CAD. By constructing dummy combined variables, elevated Lp(a) accompanied with diabetes or high levels of serum glucose, apoB and cholesterol exhibited an amplified high risk for CAD.

CONCLUSIONS

The results indicate that serum Lp(a) does interact multiplicatively with diabetes, apoB and cholesterol. The simultaneous assessment of Lp(a) and interactive risk factors enhances the discriminating value for CAD.

Type 2 diabetes but not coronary atherosclerosis is an independent determinant of impaired mobility in angiographied coronary patients

AIMS

We aimed at determining the associations of type 2 diabetes (T2DM) and of angiographically determined coronary artery disease (CAD) with impaired mobility.

METHODS

We enrolled 747 consecutive patients undergoing coronary angiography for the evaluation of stable CAD. Mobility was assessed by the standardized timed-up-and-go (TUG) test, a functional test of physical performance.

RESULTS

Mobility was impaired (TUG time >10s) in 199 (26.6%) patients. The proportion of subjects with impaired mobility was higher among patients with T2DM than among non-diabetic individuals (40.2% vs. 22.0%; p<0.001), whereas it did not differ significantly between patients with significant coronary stenoses >or=50% and those without such lesions (p=0.802). Multivariate adjustment in logistic regression analyses confirmed that T2DM (adjusted odds ratio (OR)=2.05 [95% CI 1.35-3.11]; p=0.001) but not the presence of significant coronary stenoses (adjusted OR=0.81 [0.55-1.21]; p=0.306) was independently associated with impaired mobility.

CONCLUSIONS

T2DM but not coronary atherosclerosis is an independent determinant of impaired mobility in the high risk population of angiographied coronary patients. Mobility enhancing exercise programs are needed for diabetic coronary patients.

Alanine aminotransferase and gamma-glutamyl transferase are associated with the metabolic syndrome but not with angiographically determined coronary atherosclerosis

BACKGROUND

Recently, elevated liver enzymes have attracted great interest as potential novel markers of cardiovascular risk. Their association with angiographically determined coronary artery disease (CAD) is unknown.

METHODS

We enrolled 1000 consecutive patients undergoing coronary angiography for the evaluation of suspected or established stable CAD. The metabolic syndrome (MetS) was defined according to ATP-III criteria; significant CAD was diagnosed in the presence of coronary stenoses with lumen narrowing >or=50%.

RESULTS

Serum alanine aminotransferase (ALT), the ALT/aspartate aminotransferase (AST) ratio, and serum gamma-glutamyl transferase (GGT) were significantly higher in patients with the MetS than in subjects without the MetS (34+/-21 vs. 29+/-20 U/l; p<0.001, 1.16+/-0.39 vs. 1.00+/-0.36 U/l, p<0.001; and 53+/-88 vs. 43+/-57 U/l, p=0.001, respectively) but were similar in patients with significant CAD as in those who did not have significant CAD at angiography (p=0.592; p=0.731, and p=0.716, respectively). Analysis of covariance after multivariate adjustment including alcohol consumption confirmed that ALT, ALT/AST ratio, and GGT were significantly and independently associated with the MetS but not with significant CAD.

CONCLUSIONS

ALT, the ALT/AST ratio, and GGT are associated with the MetS but not with angiographically determined coronary atherosclerosis.

Type 2 diabetes significantly modulates the cardiovascular risk conferred by the PAI-1 -675 4G/5G polymorphism in angiographied coronary patients

BACKGROUND

The association of the -675 4G/5G polymorphism of the plasminogen activator inhibitor-1 (PAI-1) gene with cardiovascular disease in patients with type 2 diabetes (T2DM) is unknown.

METHODS

Genotyping was performed in 672 consecutive Caucasian patients undergoing coronary angiography for the evaluation of stable coronary artery disease (CAD). Vascular events were recorded over 4 years.

RESULTS

In non-diabetic subjects (n=524), the homozygous PAI-1 4G4G genotype was significantly associated with significant coronary stenoses>or=50% (adjusted odds ratio (OR) OR=1.84 [1.17-2.92]; p=0.009); however, in T2DM patients (n=148) no such association was observed (OR=0.67 [0.26-1.71]; p=0.401). An interaction term T2DMx4G4G genotype was significant (p=0.006), indicating a significantly stronger association of the polymorphism with CAD in non-diabetic subjects than in patients with T2DM. Also prospectively, the 4G4G genotype conferred an increased risk of vascular events in non-diabetic subjects but not in T2DM patients (hazard ratios 1.76 [1.13-2.74]; p=0.014 and 0.68 [0.30-1.54]; p=0.360, respectively). Again, the interaction T2DMx4G4G genotype was significant (p=0.018).

CONCLUSIONS

Presence of T2DM significantly modulates the vascular risk conferred by the PAI-1 -675 4G/5G polymorphism in angiographied coronary patients.

Impact of elevated serum lipoprotein (a) concentrations on the risk of coronary heart disease in patients with type 2 diabetes mellitus

Type 2 diabetes mellitus is associated with a marked increase of coronary heart disease (CHD). We aimed to assess the impact of elevated serum lipoprotein (a) (Lp[a]) concentrations on the risk of CHD in patients with type 2 diabetes mellitus. A consecutive series of 352 outpatients was investigated. We determined the serum lipid profile and checked the patients for a history of CHD and of its traditional risk factors. Furthermore, the patients were divided into 3 groups according to the degree of elevation of the serum Lp(a) concentration: serum Lp(a) concentrations greater than 50 mg/dL, between 30 and 50 mg/dL, and less than 30 mg/dL, a presumed high normal value; and the prevalence of CHD was compared among the 3 groups. The serum Lp(a) concentrations in the subjects varied widely from 0.4 to 163.6 mg/dL. Patients with CHD had significantly higher serum Lp(a) concentrations than those without CHD (P = .0045). Logistic regression analysis to identify factors associated with the presence of CHD revealed that elevated serum Lp(a) is a significant risk factor (P = .0246). The prevalence of CHD increased with increasing serum Lp(a) concentrations (P = .048). Patients with serum Lp(a) concentrations greater than 50 mg/dL had a significantly higher prevalence of CHD than those with serum Lp(a) concentrations less than 30 mg/dL: the odds ratio of an elevated serum Lp(a) concentration was 3.346 (P = .039). In conclusion, elevated serum Lp(a) is a significant risk factor; and the risk of CHD appears to increase with increasing serum Lp(a) concentrations. Serum Lp(a) concentration of 50 mg/dL might represent a threshold level in relation to the risk of CHD in patients with type 2 diabetes mellitus.

Metabolic and anti-inflammatory benefits of eccentric endurance exercise - a pilot study

BACKGROUND

Eccentric endurance exercise (e.g. hiking downwards) is less strenuous than concentric exercise (e.g. hiking upwards) but its potential to reduce cardiovascular risk is unknown.

MATERIALS AND METHODS

We randomly allocated 45 healthy sedentary individuals (16 men and 29 women, mean age 48 years) to one of two groups, one beginning with two months of hiking upwards, the other with two months of hiking downwards the same route, with a crossover for a further two months. For the opposite way, a cable car was used where compliance was recorded electronically. The difference in altitude was 540 metres; the distance was covered three to five times a week. Fasting and postprandial metabolic profiles were obtained at baseline and after the two month periods of eccentric and concentric exercise, respectively.

RESULTS

Forty-two of the 45 participants completed the study; the compliance rate was therefore 93%. Compared with baseline, eccentric exercise lowered total cholesterol (by 4.1%; P = 0.026), low-density lipoprotein (LDL) cholesterol (by 8.4%, P = 0.001), Apolipoprotein B/Apolipoprotein A1 ratio (by 10.9%, P < 0.001), homeostasis model assessment of insulin resistance scores (by 26.2%, P = 0.017) and C-reactive protein (by 30.0%; P = 0.007); the magnitude of these changes was comparable to that of concentric exercise. Eccentric exercise improved glucose tolerance (by 6.2%, P = 0.023), whereas concentric exercise improved triglyceride tolerance (by 14.9%, P = 0.022).

CONCLUSIONS

Eccentric endurance exercise is a promising new exercise modality with favourable metabolic and anti-inflammatory effects and is well applicable to sedentary individuals.

Effect of pioglitazone on atherogenic outcomes in type 2 diabetic patients: a comparison of responders and non-responders

The aim of this study was to evaluate the anti-atherogenic efficacy of pioglitazone, a thiazolidinedione derivative, on the change in atherogenic outcomes by comparing responder and non-responder groups in type 2 diabetic patients. Twenty-three patients with poor diabetic control were treated with 15 mg of pioglitazone for 12 months. The levels of fasting plasma glucose (FPG), HbA1c, triglycerides (TG), total cholesterol (T-Cho), low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) were measured monthly, and those of remnant-like particle-cholesterol (RLP-C) and lipoprotein (a) [Lp (a)] were measured every 3 months. In Month 6, the patients were divided into two groups according to the decrease in HbA1c level: the responder group showed a decrease of > or =1%; the non-responder group, a decrease of <1%. In the responder group, the levels of FPG and HbA1c decreased significantly after Month 3. The values of the body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR) index, LDL-C, and RLP-C were significantly higher in the responder group than in the non-responder group. Although the levels of T-Cho and HDL-C were unchanged in both groups, those of TG and RLP-C were drastically reduced in the responder group. Interestingly, the relative change in Lp (a) was significantly decreased in both groups. These results strongly suggest that pioglitazone is beneficial for type 2 diabetic patients with high levels of BMI, HOMA-IR, LDL-C, and RLP-C, as it helps to prevent the progression of atherosclerosis, including coronary heart diseases.

Plasma Lipoprotein(a) Indicates Risk for 4 Distinct Forms of Vascular Disease

Background: Increased lipoprotein(a) [Lp(a)] concentrations are predictive for coronary artery disease (CAD). The risk conferred by Lp(a) for other types of vascular disease compared with CAD has not been investigated within a single population. This study aimed to investigate Lp(a) risk association for 4 different types of vascular disease (including CAD) within a predominantly white population.

Methods: We used an Lp(a) ELISA that measures Lp(a) independently of apolipoprotein(a) size to measure plasma Lp(a) in patients [384 CAD, 262 peripheral vascular disease, 184 ischemic stroke (stroke), 425 abdominal aortic aneurysm] and 230 disease-free controls. We then conducted association studies with logistic regression, integrating the potential confounding effects of age, sex, diabetes, plasma lipids, and a history of previous hypertension, hypercholesterolemia, and smoking.

Results: Multivariate analyses with Lp(a) concentrations of &gt;45 nmol/L (the 75th percentile value for controls) as the clinical cutoff showed increased Lp(a) concentrations to be a risk factor for all disease groups, with adjusted odds ratios ranging from 1.96 [95% confidence interval (CI) 1.24–3.08] for CAD to 2.33 (95% CI 1.39–3.89) for PVD. The risk conferred by Lp(a) appeared to be independent of other confounders, including exposure to statin/fibrate therapies. Similar odds ratios and CIs between disease groups indicated that increased Lp(a) conferred a similar risk for all groups studied.

Conclusions: Lp(a) constitutes a stable risk factor of similar magnitude for 4 major forms of vascular disease. This association was not altered by exposure to standard lipid-lowering therapy.

Effects of nateglinide and glibenclamide on prothrombotic factors in naïve type 2 diabetic patients treated with metformin: a 1-year, double-blind, randomized clinical trial

OBJECTIVE

To evaluate the effect on coagulation and fibrinolysis parameters and on non-conventional cardiovascular risk factors of metformin plus nateglinide or glibenclamide in naïve type 2 diabetes patients.

PATIENTS AND METHODS

A total of 248 type 2 diabetic patients were enrolled and randomly assigned to receive nateglinide or glibenclamide, and metformin for 12 months. We assessed body mass index (BMI), glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), postprandial plasma insulin (PPI), homeostasis model assessment index (HOMA index), lipid profile with lipoprotein (a) [Lp(a)], fibrinogen (Fg), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), homocysteine (Hcy), systolic blood pressure (SBP), diastolic blood pressure (DBP).

RESULTS

After 9 months of treatment, both tested drug combinations were similarly associated with a significant reduction in FPG (nateglinide, -17.2%; glibenclamide, -16.9%, both p<0.05) compared to the baseline, while HbA1c (-17.3%, p<0.05) and PPG (-15.2%, p<0.05) significantly decreased only in the nateglinide group. After one year of treatment, compared to the baseline the nateglinide group showed a significant reduction in HbA1c (-21%, p<0.01), FPG (-20.7%), p<0.01, PPG (-21.5%, p<0.05), HOMA index (-25.4%, p<0.05); the glibenclamide group, showed a significant reduction in HbA1c (-11%, p<0.05), FPG (-23.2%, p<0.05), PPG (-11.2%, p<0.05), and HOMA index (-23.9%, p<0.05) but to a minor extent. Moreover, the HbA1c difference value from baseline observed in the nateglinide-treated group was significantly higher than that observed in the glibenclamide group. Therefore the nateglinide-treated patients showed a significant reduction in some prothrombotic parameters (PAI-1=-19%, Lp(a)=-31%, and Hcy=-32.3%, all p<0.05), whereas the glibenclamide-treated patients did not.

CONCLUSION

Nateglinide appears to improve glycemic control as well as the levels of some prothrombotic parameters compared to glibenclamide when administered in combination with metformin.

Value of serum glycated albumin and high-sensitivity C-reactive protein levels in the prediction of presence of coronary artery disease in patients with type 2 diabetes

Background

Coronary artery disease (CAD) is a major vascular complication of diabetes mellitus and reveals high mortality. Up to 30% of diabetic patients with myocardial ischemia remain asymptomatic and are associated with worse prognosis compared to non-diabetic counterpart, which warrants routine screening for CAD in diabetic population. The purpose of this study was to evaluate the clinical value of serum glycated albumin and high-sensitivity C-reactive protein (hs-CRP) levels in predicting the presence of CAD in patients with type 2 diabetes.

Methods

Three hundred and twenty-four patients with type 2 diabetes were divided into two groups based on presence (CAD group, n = 241) or absence (control group, n = 83) of angiographically-documented CAD (lumen diameter narrowing ≥70%). Serum levels of glycated albumin and hs-CRP as well as serum concentrations of glucose, lipids, creatinine, blood urea nitrogen and uric acid were measured in both groups. Predictors of CAD were determined using multivariate logistic regression model and receiver-operating characteristic (ROC) curves.

Results

Serum glycated albumin and hs-CRP levels were significantly increased in diabetic patients with CAD. Multivariate regression analysis revealed that male gender, age, serum levels of glycated albumin, hs-CRP, creatinine and lipoprotein (a) were independent predictors for CAD. Areas under the curve of glycated albumin and hs-CRP and for regression model were 0.654 (95%CI 0.579–0.730, P < 0.001), 0.721 (95%CI 0.658–0.785, P < 0.001) and 0.824 (95% CI 0.768–0.879, P < 0.001), respectively. The optimal values of cut-off point were 18.7% (sensitivity 67.9%, specificity 60.0%) for glycated albumin and 5.2 mg/l (sensitivity 72.2%, specificity 60.0%) for hs-CRP to predict CAD. Logistic regression model was defined as: P/(1-P) = EXP(-1.5 + 1.265 gender + 0.812 age + 1.24 glycated albumin + 0.953 hs-CRP + 0.902 lipoprotein(a) + 1.918 creatinine). The optimal probability value for predicting CAD in type 2 diabetic patients was 0.648 (sensitivity 82.3%, specificity 68.6%).

Conclusion

Serum glycated albumin and hs-CRP levels were significantly elevated in patients with type 2 diabetes and CAD. The logistic regression model incorporating with glycated albumin, hs-CRP and other major risk factors of atherosclerosis may be useful for screening CAD in patients with type 2 diabetes.