K M Welch

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.

Baseline blood pressure, low- and high-density lipoproteins, and triglycerides and the risk of vascular events in the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial

OBJECTIVE To explore the relative contributions of baseline systolic blood pressure (SBP) and diastolic blood pressure (DBP) and lipoproteins on the risk of recurrent stroke or first major cardiovascular event (MCVE) and their potential impact on the benefit of statin treatment. METHODS AND RESULTS The SPARCL trial randomized 4731 patients with recent stroke or transient ischemic attack (TIA) and no known coronary heart disease and LDL-C between 100 and 190 mg/dL to either atorvastatin 80 mg/d or placebo. Baseline assessment included SBP, DBP and measurements of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), and triglyceride levels. After 4.9 years of follow-up, there were 575 primary end points (fatal and nonfatal stroke), including 491 ischemic strokes, and 740 MCVEs (stroke plus myocardial infarction and vascular death). Cox regression models analysis showed a trend (P>0.05 and P<0.10) for higher SBP but not DBP to be associated with an outcome stroke with only SBP associated with MCVE. Only baseline low HDL-C was associated with an outcome stroke. Baseline HDL-C, triglycerides, and LDL/HDL ratio were each associated with MCVEs. There were no interactions between any of these baseline variables and the effect of treatment on outcome strokes. CONCLUSIONS In patients with recent stroke or TIA and no coronary heart disease, only lower baseline HDL-C predicted the risk of recurrent stroke with HDL-C, triglycerides, and LDL/HDL ratio associated with MCVE. Atorvastatin treatment was similarly effective regardless of baseline lipoprotein levels.

Relative and Cumulative Effects of Lipid and Blood Pressure Control in the Stroke Prevention by Aggressive Reduction in Cholesterol Levels Trial

Background and Purpose— The relative contributions of on-treatment low- and high-density lipoprotein cholesterol (LDL-C, HDL-C), triglycerides, and blood pressure (BP) control on the risk of recurrent stroke or major cardiovascular events in patients with stroke is not well defined. Methods— We randomized 4731 patients with recent stroke or transient ischemic attack and no known coronary heart disease to atorvastatin 80 mg per day or placebo. Results— After 4.9 years, at each level of LDL-C reduction, subjects with HDL-C value above the median or systolic BP below the median had greater reductions in stroke and major cardiovascular events and those with a reduction in triglycerides above the median or diastolic BP below the median showed similar trends. There were no statistical interactions between on-treatment LDL-C, HDL-C, triglycerides, and BP values. In a further exploratory analysis, optimal control was defined as LDL-C <70 mg per deciliter, HDL-C >50 mg per deciliter, triglycerides <150 mg per deciliter, and SBP/DBP <120/80 mm Hg. The risk of stroke decreased with as the level of control increased (hazard ratio [95% confidence interval] 0.98 [0.76 to 1.27], 0.78 [0.61 to 0.99], 0.62 [0.46 to 0.84], and 0.35 [0.13 to 0.96]) for those achieving optimal control of 1, 2, 3, or 4 factors as compared to none, respectively. Results were similar for major cardiovascular events. Conclusions— We found a cumulative effect of achieving optimal levels of LDL-C, HDL-C, triglycerides, and BP on the risk of recurrent stroke and major cardiovascular events. The protective effect of having a higher HDL-C was maintained at low levels of LDL-C.

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

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.

Levels and Changes of HDL Cholesterol and Apolipoprotein A-I in Relation to Risk of Cardiovascular Events Among Statin-Treated PatientsClinical Perspective

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.