D. John Betteridge

Primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS): multicentre randomised placebo-controlled trial

BACKGROUND Type 2 diabetes is associated with a substantially increased risk of cardiovascular disease, but the role of lipid-lowering therapy with statins for the primary prevention of cardiovascular disease in diabetes is inadequately defined. We aimed to assess the effectiveness of atorvastatin 10 mg daily for primary prevention of major cardiovascular events in patients with type 2 diabetes without high concentrations of LDL-cholesterol. METHODS 2838 patients aged 40-75 years in 132 centres in the UK and Ireland were randomised to placebo (n=1410) or atorvastatin 10 mg daily (n=1428). Study entrants had no documented previous history of cardiovascular disease, an LDL-cholesterol concentration of 4.14 mmol/L or lower, a fasting triglyceride amount of 6.78 mmol/L or less, and at least one of the following: retinopathy, albuminuria, current smoking, or hypertension. The primary endpoint was time to first occurrence of the following: acute coronary heart disease events, coronary revascularisation, or stroke. Analysis was by intention to treat. FINDINGS The trial was terminated 2 years earlier than expected because the prespecified early stopping rule for efficacy had been met. Median duration of follow-up was 3.9 years (IQR 3.0-4.7). 127 patients allocated placebo (2.46 per 100 person-years at risk) and 83 allocated atorvastatin (1.54 per 100 person-years at risk) had at least one major cardiovascular event (rate reduction 37% [95% CI -52 to -17], p=0.001). Treatment would be expected to prevent at least 37 major vascular events per 1000 such people treated for 4 years. Assessed separately, acute coronary heart disease events were reduced by 36% (-55 to -9), coronary revascularisations by 31% (-59 to 16), and rate of stroke by 48% (-69 to -11). Atorvastatin reduced the death rate by 27% (-48 to 1, p=0.059). No excess of adverse events was noted in the atorvastatin group. INTERPRETATION Atorvastatin 10 mg daily is safe and efficacious in reducing the risk of first cardiovascular disease events, including stroke, in patients with type 2 diabetes without high LDL-cholesterol. No justification is available for having a particular threshold level of LDL-cholesterol as the sole arbiter of which patients with type 2 diabetes should receive statins. The debate about whether all people with this disorder warrant statin treatment should now focus on whether any patients are at sufficiently low risk for this treatment to be withheld.

Very low levels of atherogenic lipoproteins and the risk for cardiovascular events: a meta-analysis of statin trials.

BACKGROUND Levels of atherogenic lipoproteins achieved with statin therapy are highly variable, but the consequence of this variability for cardiovascular disease risk is not well-documented. OBJECTIVES The aim of this meta-analysis was to evaluate: 1) the interindividual variability of reductions in low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), or apolipoprotein B (apoB) levels achieved with statin therapy; 2) the proportion of patients not reaching guideline-recommended lipid levels on high-dose statin therapy; and 3) the association between very low levels of atherogenic lipoproteins achieved with statin therapy and cardiovascular disease risk. METHODS This meta-analysis used individual patient data from 8 randomized controlled statin trials, in which conventional lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up. RESULTS Among 38,153 patients allocated to statin therapy, a total of 6,286 major cardiovascular events occurred in 5,387 study participants during follow-up. There was large interindividual variability in the reductions of LDL-C, non-HDL-C, and apoB achieved with a fixed statin dose. More than 40% of trial participants assigned to high-dose statin therapy did not reach an LDL-C target <70 mg/dl. Compared with patients who achieved an LDL-C >175 mg/dl, those who reached an LDL-C 75 to <100 mg/dl, 50 to <75 mg/dl, and <50 mg/dl had adjusted hazard ratios for major cardiovascular events of 0.56 (95% confidence interval [CI]: 0.46 to 0.67), 0.51 (95% CI: 0.42 to 0.62), and 0.44 (95% CI: 0.35 to 0.55), respectively. Similar associations were observed for non-HDL-C and apoB. CONCLUSIONS The reductions of LDL-C, non-HDL-C, and apoB levels achieved with statin therapy displayed large interindividual variation. Among trial participants treated with high-dose statin therapy, >40% did not reach an LDL-C target <70 mg/dl. Patients who achieve very low LDL-C levels have a lower risk for major cardiovascular events than do those achieving moderately low levels.

An International Atherosclerosis Society Position Paper: Global recommendations for the management of dyslipidemia

An international panel of the International Atherosclerosis Society has developed a new set of recommendations for management of dyslipidemia. The panel identifies non-high density lipoprotein cholesterol (non-HDL-C) as the major atherogenic lipoprotein. Primary and secondary prevention are considered separately. Optimal levels for atherogenic lipoproteins are derived for the two forms of prevention. For primary prevention, the recommendations emphasize lifestyle therapies to reduce atherogenic lipoproteins; drug therapy is reserved for higher risk subjects. Risk assessment is based on estimation of lifetime risk according to differences in baseline population risk in different nations or regions. Secondary prevention emphasizes use of cholesterol-lowering drugs to attain optimal levels of atherogenic lipoproteins.

Effects of atorvastatin on kidney outcomes and cardiovascular disease in patients with diabetes: an analysis from the Collaborative Atorvastatin Diabetes Study (CARDS).

BACKGROUND We examined whether atorvastatin affects diabetic kidney disease and whether the effect of atorvastatin on cardiovascular disease (CVD) varies by kidney status in patients with diabetes. STUDY DESIGN The Collaborative Atorvastatin Diabetes Study (CARDS) randomized placebo-controlled trial. SETTING & PARTICIPANTS Patients with type 2 diabetes and no prior CVD (n = 2,838). INTERVENTION Random allocation to atorvastatin, 10 mg/d, or placebo, with a median follow-up of 3.9 years. OUTCOMES Estimated glomerular filtration rate (eGFR), albuminuria, CVD. MEASUREMENTS Baseline and follow-up GFRs were estimated by using the Modification of Diet in Renal Disease Study equation. Urinary albumin-creatinine ratio was measured on spot urine samples. RESULTS At baseline, 34% of patients had an eGFR of 30 to 60 mL/min/1.73 m(2). Atorvastatin treatment was associated with a modest improvement in annual change in eGFR (net, 0.18 mL/min/1.73 m(2)/y; 95% confidence interval [CI], 0.04 to 0.32; P = 0.01) that was most apparent in those with albuminuria (net improvement, 0.38 mL/min/1.73 m(2)/y; P = 0.03). At baseline, 21.5% of patients had albuminuria and an additional 6.8% developed albuminuria during follow-up. Atorvastatin did not influence the incidence of albuminuria (hazard ratio, 1.49; 95% CI, 0.73 to 3.04; P = 0.3) or regression to normoalbuminuria (hazard ratio, 1.19; 95% CI, 0.57 to 2.49; P = 0.6). In 970 patients with a moderately decreased eGFR of 30 to 60 mL/min/1.73 m(2), there was a 42% reduction in major CVD events with treatment, including a 61% reduction in stroke. This treatment effect was similar to the 37% (95% CI, 17 to 52; P < 0.001) reduction in CVD observed in the study overall (P = 0.4 for the eGFR-treatment interaction). LIMITATIONS Low incidence rates of albuminuria and transition to more severe kidney status limit power to detect treatment effects. CONCLUSIONS A modest beneficial effect of atorvastatin on eGFR, particularly in those with albuminuria, was observed. Atorvastatin did not influence albuminuria incidence. Atorvastatin was effective at decreasing CVD in those with and without a moderately decreased eGFR and achieved a high absolute benefit.

Fasting and postprandial determinants for the occurrence of small dense LDL species in non-insulin-dependent diabetic patients with and without hypertriglyceridaemia: the involvement of insulin, insulin precursor species and insulin resistance

We have studied low density lipoprotein (LDL) subclass distribution in a group of male patients with non-insulin-dependent diabetes mellitus (NIDDM) and investigated its relationships to fasting and postprandial triglyceride (TG)-rich lipoproteins, insulin resistance, lipoprotein lipase (EC 3.1.1.3; LPL), hepatic lipase (EC 3.1.1.34; HL), lecithin:cholesterol acyl transferase (EC 2.3.1.43; LCAT) and cholesteryl ester transfer protein (CETP) activities. LDL was subfractionated by density gradient ultracentrifugation. Postprandial lipoproteins were measured after an oral fat load using retinyl palmitate as a marker for intestinal TG-rich lipoproteins. Hypertriglyceridaemic NIDDMs (HTG) had a preponderance of small dense LDL particles present in the plasma and reduced amounts of large buoyant species when compared to normotriglyceridaemic patients (NTG) and controls. Both groups of diabetics were more insulin resistant than the controls (P < 0.05) and had raised concentrations of proinsulin (P < 0.05), although insulin content did not differ significantly. 32-33 split proinsulin (SPI) was the major insulin-like molecule present in HTG and was present in significantly higher amounts in these patients (P < 0.05) than either NTG or control subjects and correlated significantly with the presence of small dense LDL particles. After a test meal, the postprandial chylomicron response was greater in HTG than either NTG diabetics or controls (P < 0.05). Chylomicron remnants were present to a greater extent in HTG than in NTG and controls (P < 0.05), although in this case NTG also contained more chylomicron remnants than control subjects (P < 0.05). There was no difference in the LPL activity, CETP and LCAT between diabetics and controls, whereas an increase in hepatic lipase activity was seen in the HTG diabetics (P < 0.05). Both CETP and LCAT activities increased postprandially. Multivariate analysis showed that TG, HDL content and HL activity were the most important determinants of small dense LDL concentration in the fasting state (R2 = 67%). Postprandially, chylomicron remnant clearance, HL and insulin resistance were the major determinants (R2 = 61%) of LDL-III.

Total Soluble and Endogenous Secretory Receptor for Advanced Glycation End Products as Predictive Biomarkers of Coronary Heart Disease Risk in Patients With Type 2 Diabetes An Analysis From the CARDS Trial

OBJECTIVE Circulating levels of soluble receptor for advanced glycation end products (sRAGE) likely comprise both a secreted isoform (esRAGE) and wild-type RAGE cleaved from the cell membrane. Both sRAGE and esRAGE have been proposed as biomarkers of cardiovascular disease (CVD), but prospective data are limited. We examined the relationship of sRAGE and esRAGE to incident coronary heart disease (CHD) and stroke in type 2 diabetic patients followed for 3.9 years in a trial of atorvastatin: the Collaborative Atorvastatin Diabetes Study (CARDS). RESEARCH DESIGN AND METHODS We used a nested case-control design sampling all incident cases of CVD with available plasma and randomly selecting three control subjects, who were free of CVD throughout follow-up, per case. Analysis was by Cox regression with adjustment for treatment allocation and relevant covariates. RESULTS sRAGE and esRAGE were strongly correlated (ρ = 0.88) and were both higher in those with lower BMI (P < 0.001), higher adiponectin (P < 0.001), lower estimated glomerular filtration rate (P = 0.009), and white ethnicity (P < 0.001). Both sRAGE and esRAGE were associated with incident CHD events, independently of treatment allocation and the above factors; hazard ratio (HR) = 1.74 (95% CI 1.25–2.41; P = 0.002) for a doubling of the sRAGE level; HR = 1.45 (1.11–1.89; P = 0.006) for a doubling of the esRAGE level. There was no significant association with stroke; HR for sRAGE = 0.66 (0.38–1.14). Atorvastatin, 10 mg daily, did not alter sRAGE. CONCLUSIONS Higher levels of sRAGE and esRAGE are associated with incident CHD but not stroke in type 2 diabetes.

Human cytomegalovirus seropositivity is associated with impaired vascular function

Background—Herpesvirus infection is a possible risk factor for atherogenesis, and diabetics may be at particular risk. Endothelial dysfunction is an early marker for atherosclerosis, and the present study tests the hypotheses that (1) prior infection with cytomegalovirus (CMV) and herpes simplex virus (HSV) is associated with endothelial dysfunction and (2) this may be more marked in diabetics. Methods and Results—Serum samples were tested for anti-IgG antibodies to CMV and HSV from 400 subjects (mean age for diabetics and nondiabetics, 37.8±4.3 and 37.9±3.7 [SD]). We also assessed Helicobacter pylori and Chlamydia pneumoniae serology. Coronary atheroma was quantified by means of electron beam computed tomography. Subjects (n=157) underwent venous occlusion plethysmography with acetylcholine, bradykinin, glyceryl trinitrate, norepinephrine, and l-NG-monomethyl-l-arginine. Individuals who were seropositive for CMV had reduced responses to bradykinin (P =0.005) and glyceryl trinitrate (P =0.006). The reduced response to bradykinin remained significant (P =0.045) after adjusting for the response to glyceryl trinitrate and was independent of conventional risk factors. Positive serology for the other organisms did not have an independent effect on reactivity. There was a weaker association between CMV and coronary artery calcification (P =0.09). Positive serology for each of the other pathogens did not affect reactivity, but there was a relation between total pathogen burden and impaired vascular reactivity. No significant differences were found between diabetics and nondiabetics. Conclusions—This study shows that CMV-seropositive individuals have endothelial dysfunction and impaired responses to NO. This association was independent of conventional risk factors and may be associated with increased atherosclerosis burden.

Linkage and Association Between Distinct Variants of the APOA1/C3/A4/A5 Gene Cluster and Familial Combined Hyperlipidemia

Objective—Combined hyperlipidemia is a common disorder, characterized by a highly atherogenic lipoprotein profile and a substantially increased risk of coronary heart disease. The purpose of this study was to establish whether variations of apolipoprotein A5 (APOA5), a newly discovered gene of lipid metabolism located 30 kbp downstream of the APOA1/C3/A4 gene cluster, contributes to the transmission of familial combined hyperlipidemia (FCHL). Methods and Results—We performed linkage and association tests on 128 families. Two independent alleles, APOA5c.56G and APOC3c.386G, of the APOA1/C3/A4/A5 gene cluster were overtransmitted in FCHL (P =0.004 and 0.007, respectively). This was paired with reduced transmission of the common APOA1/C3/A4/A5 haplotype (frequency 0.4461) to affected subjects (P =0.012). The APOA5c.56G genotype accounted for 7.3% to 13.8% of the variance in plasma triglyceride levels in probands (P <0.004). The APOC3c.386G genotypes accounted for 4.4% to 5.1% of the variance in triglyceride levels in FCHL spouses (P <0.007), suggesting that this allele marks a FCHL quantitative trait as well as representing a susceptibility locus for the condition. Conclusions—A combined linkage and association analysis establishes that variation at the APOA1/C3/A4/A5 gene cluster contributes to FCHL transmission in a substantial proportion of northern European families.

Levels and Changes of HDL Cholesterol and Apolipoprotein A-I in Relation to Risk of Cardiovascular Events Among Statin-Treated Patients: A Meta-Analysis

Background— It is unclear whether levels of high-density lipoprotein cholesterol (HDL-C) or apolipoprotein A-I (apoA-I) remain inversely associated with cardiovascular risk among patients who achieve very low levels of low-density lipoprotein cholesterol on statin therapy. It is also unknown whether a rise in HDL-C or apoA-I after initiation of statin therapy is associated with a reduced cardiovascular risk. Methods and Results— We performed a meta-analysis of 8 statin trials in which lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up. Individual patient data were obtained for 38 153 trial participants allocated to statin therapy, of whom 5387 suffered a major cardiovascular event. HDL-C levels were associated with a reduced risk of major cardiovascular events (adjusted hazard ratio [HR], 0.83; 95% confidence interval [CI], 0.81–0.86 per 1 standard deviation increment), as were apoA-I levels (HR, 0.79; 95% CI, 0.72–0.82). This association was also observed among patients achieving on-statin low-density lipoprotein cholesterol levels <50 mg/dL. An increase of HDL-C was not associated with reduced cardiovascular risk (HR, 0.98; 95% CI, 0.94–1.01 per 1 standard deviation increment), whereas a rise in apoA-I was (HR, 0.93; 95% CI, 0.90–0.97). Conclusions— Among patients treated with statin therapy, HDL-C and apoA-I levels were strongly associated with a reduced cardiovascular risk, even among those achieving very low low-density lipoprotein cholesterol. An apoA-I increase was associated with a reduced risk of major cardiovascular events, whereas for HDL-C this was not the case. These findings suggest that therapies that increase apoA-I concentration require further exploration with regard to cardiovascular risk reduction.

Genome-wide association study of genetic determinants of LDL-c response to atorvastatin therapy: importance of Lp(a).

We carried out a genome-wide association study (GWAS) of LDL-c response to statin using data from participants in the Collaborative Atorvastatin Diabetes Study (CARDS; n = 1,156), the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT; n = 895), and the observational phase of ASCOT (n = 651), all of whom were prescribed atorvastatin 10 mg. Following genome-wide imputation, we combined data from the three studies in a meta-analysis. We found associations of LDL-c response to atorvastatin that reached genome-wide significance at rs10455872 (P = 6.13 × 10−9) within the LPA gene and at two single nucleotide polymorphisms (SNP) within the APOE region (rs445925; P = 2.22 × 10−16 and rs4420638; P = 1.01 × 10−11) that are proxies for the ε2 and ε4 variants, respectively, in APOE. The novel association with the LPA SNP was replicated in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) trial (P = 0.009). Using CARDS data, we further showed that atorvastatin therapy did not alter lipoprotein(a) [Lp(a)] and that Lp(a) levels accounted for all of the associations of SNPs in the LPA gene and the apparent LDL-c response levels. However, statin therapy had a similar effect in reducing cardiovascular disease (CVD) in patients in the top quartile for serum Lp(a) levels (HR = 0.60) compared with those in the lower three quartiles (HR = 0.66; P = 0.8 for interaction). The data emphasize that high Lp(a) levels affect the measurement of LDL-c and the clinical estimation of LDL-c response. Therefore, an apparently lower LDL-c response to statin therapy may indicate a need for measurement of Lp(a). However, statin therapy seems beneficial even in those with high Lp(a).