Better survival with statin administration after revascularization therapy in Japanese patients with coronary artery disease: perspectives from the CREDO-Kyoto registry

Association between Non-Lipid Residual Risk Factors and Cardiovascular Events in Patients with Stable Coronary Artery Disease Treated with Pitavastatin: An Observation from the REAL-CAD Study

AIMS

We aimed to investigate the association between non-lipid residual risk factors and cardiovascular events in patients with stable coronary artery disease (CAD) who achieved low-density lipoprotein cholesterol (LDL-C) ＜100 mg/dL from the Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) study.

METHODS

The REAL-CAD study was a prospective, multicenter, open-label trial. As a sub-study, we examined the prognostic impact of non-lipid residual risk factors, including blood pressure, glucose level, and renal function, in patients who achieved LDL-C ＜100 mg/dL at 6 months after pitavastatin therapy. Each risk factor was classified according to severity. The primary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke, and unstable angina requiring emergency hospitalization.

RESULTS

Among 8,743 patients, the mean age was 68±8.2 years, and the mean LDL-C level was 84.4±18 mg/dL. After adjusting for the effects of confounders, an estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73 m2 showed the highest risk of the primary outcome (hazard ratio [HR] 1.92; 95% confidence interval [CI] 1.45-2.53). The combination of eGFR ≤ 60 and hemoglobin A1c (HbA1c) ≥ 6.0% also showed the highest risk of all-cause death (HR, 2.42; 95% CI, 1.72-3.41).

CONCLUSIONS

In patients with stable CAD treated with pitavastatin and who achieved guidelines-directed levels of LDL-C, eGFR and HbA1c were independently associated with adverse events, suggesting that renal function and glycemic control could be residual non-lipid therapeutic targets after statin therapy.

Impact of Lipoprotein (a) on Long-Term Outcomes in Patients With Acute Myocardial Infarction

BACKGROUND

Lipoprotein (a) (Lp(a)) is a complex circulating lipoprotein, and there is increasing evidence it is a risk factor for atherosclerotic cardiovascular disease (ASCVD). This study aimed to investigate the influence of Lp(a) serum levels on long-term outcomes after acute myocardial infarction (AMI).Methods and Results: Between January 2015 and January 2018, we enrolled 262 patients with AMI who underwent coronary angiography within 24 h of the onset of chest pain and had available Lp(a) data enabling subdivision into 2 groups: high Lp(a) (≥32 mg/dL: n=76) and low Lp(a) (<32 mg/dL: n=186). The primary endpoint was major adverse cardiac events (MACE), which was defined as a composite of cardiac death, nonfatal MI, and readmission for heart failure. Multivariate Cox regression analysis was performed to identify the predictors of MACE. The incidence of MACE was significantly higher in the high Lp(a) group than in the low Lp(a) group (32.8% vs. 19.6%, P=0.004). Multivariate analysis showed that Lp(a) ≥32 mg/dL was an independent predictor of MACE (hazard ratio 2.84, 95% confidence interval 1.25-6.60, P=0.013).

CONCLUSIONS

High Lp(a) levels were associated with worse long-term outcomes after AMI, so Lp(a) may be useful for risk assessment.

Post-Coronary Artery Bypass Medications in Dialysis Patients: Do We Need to Change Strategies?

BACKGROUND

Coronary artery bypass grafting (CABG) is frequently performed in patients with end-stage renal disease (ESRD) together with severe coronary artery disease, after which, patients with ESRD have higher surgical risk and poorer long-term outcomes. We report our experience in patients with ESRD who survived in CABG and identify predictors of long-term outcomes.

METHODS

We retrospectively investigated 93 consecutive patients with ESRD who survived to discharge after isolated CABG between January 2005 and December 2016 at our institution. Long-term outcomes, including all-cause mortality after discharge, readmission due to major adverse cardiac events, and reintervention, were evaluated. Predictors affecting long-term outcomes were also analyzed.

RESULTS

The rates of freedom from all-cause mortality after discharge in 1, 3, 5, and 10 years were 92.1, 81.3, 71.9, and 34.9%, respectively. The rates of freedom from readmission due to major adverse cardiac events in 1, 3, 5, and 10 years were 90.7, 79.1, 69.9, and 55.6%, respectively. The rates of freedom from reintervention in 1, 3, 5, and 10 years were 95.3, 86.5, 79.0, and 66.6%, respectively. Postoperative β-blocker and statin use significantly improved overall long-term survival (β-blocker, p = 0.013; statin, p = 0.009). After case-control matching, patients who received statins showed better long-term survival than those without statins. The comparison of long-term survival between patients with and without β-blockers showed no significant difference after matching.

CONCLUSIONS

After CABG, dialysis patients who survived to discharge had acceptable long-term overall survival. Post-CABG statin use in dialysis patients is a predictor of better long-term survival.

Moderate-intensity versus high-intensity statin therapy in Korean patients with angina undergoing percutaneous coronary intervention with drug-eluting stents: A propensity-score matching analysis

OBJECTIVES

It is unclear whether high-intensity statin therapy provides incremental clinical benefits over moderate-intensity statin therapy in Asian patients with angina. This study sought to compare the clinical outcomes of moderate- and high-intensity statin therapies in patients undergoing percutaneous coronary intervention (PCI) for angina in Korean patients.

METHODS

Based on the national health insurance claims data in South Korea, patients aged 18 years or older without a known history of coronary artery disease, who underwent PCI with drug-eluting stents due to angina between 2011 and 2015, were enrolled. According to the intensity of statin therapy, patients were categorized into moderate-intensity statin therapy (n = 23,863) and high-intensity statin therapy (n = 9,073) groups. The primary endpoint, defined as a composite of all-cause death and myocardial infarction, was compared between the two groups using a propensity-score matching analysis.

RESULTS

During the follow-up period (median, 2.0 years; interquartile range, 1.1-3.1), 1,572 patients had 1,367 deaths and 242 myocardial infarctions. After propensity-score matching, there were 8,939 matched pairs. There was no significant difference in the incidence of the primary endpoint between the two groups (adjusted hazard ratio of high-intensity statin therapy, 1.093; 95% confidence interval: 0.950-1.259; p = 0.212).

CONCLUSIONS

In Korean patients undergoing PCI with drug-eluting stents for angina, the high-intensity statin therapy did not provide additional clinical benefits over the moderate-intensity statin therapy.

Predictive Value of Baseline High-Sensitivity C-Reactive Protein Level and Renal Function for Patients With Acute Coronary Syndrome Undergoing Aggressive Lipid-Lowering Therapy: A Subanalysis of HIJ-PROPER

The systematic inflammatory response might confound renal impairment, and both have been reported to affect clinical outcomes after acute coronary syndrome. We examined the impacts of the high-sensitivity C-reactive protein (hsCRP) level and estimated glomerular filtration rate level on the prognosis for acute coronary syndrome patients who underwent aggressive lipid-lowering therapy in contemporary practice. This was a subanalysis of the HIJ-PROPER study, and 1,734 patients were enrolled. Patients were divided into 4 groups using an hsCRP value of 10mg/L and an estimated glomerular filtration rate value of 60 ml/min/1.73 m² as the cut-off points. Groups were defined as follows: group A, low hsCRP and normal or mild renal impairment; group B, low hsCRP and renal impairment; group C, high hsCRP and normal or mild renal impairment; and group D, high hsCRP and renal impairment. The primary end point was defined as the composite of all-cause death, nonfatal myocardial infarction, nonfatal stroke, and unstable angina or coronary revascularizations. The median follow-up period was 3.9years, and the follow-up rate was 99%. Compared with group A, the 2 higher hsCRP groups (groups C and D) showed a significantly higher incidence of primary end points (hazard ratio 1.36, 95% confidence interval 1.12 to 1.65, p = 0.002; and hazard ratio 1.40, 95% CI 1.10 to 1.80, p = 0.008). Such a difference was not found compared with group B. In conclusion, patients with higher hsCRP levels had worse prognoses regardless of renal impairment and aggressive lipid-lowering therapy.

Rationale and Design of Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) Trial

Large-scale clinical trials in patients in Western countries with coronary artery disease (CAD) have found that aggressive lipid-lowering therapy using high-dose statins reduces cardiovascular (CV) events further than low-dose statins. However, such evidence has not yet been fully established in Asian populations, including in Japan. The Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) study addresses whether intensification of statin therapy improves clinical outcomes in Japanese patients with CAD.REAL-CAD is a prospective, multicenter, randomized, open-label, blinded-endpoint, physician-initiated phase 4 trial in Japan. The study will recruit up to 12,600 patients with stable CAD. Patients are assigned to receive either pitavastatin 1 mg/day or pitavastatin 4 mg/day. LDL-C levels are expected to reach approximate mean values of 100 mg/dL in the low-dose pitavastatin group and 80 mg/dL in the high-dose group. The primary endpoint is the time to occurrence of a major CV event, including CV death, non-fatal myocardial infarction, non-fatal ischemic stroke, and unstable angina requiring emergency hospitalization during an average of 5 years. The large number of patients and the long follow-up period in the REAL-CAD study should ensure that there is adequate power to definitively determine if reducing LDL-C levels to approximately 80 mg/dL by high-dose statin can provide additional clinical benefit.After the study is completed, we will have categorical evidence on the optimal statin dose and target LDL-C level for secondary prevention in Japanese patients.

Is Bilateral Internal Mammary Arterial Grafting Beneficial for Patients Aged 75 Years or Older?

BACKGROUND

Although bilateral internal mammary artery (BIMA) grafting is performed with increasing regularity in elderly patients, whether it is truly beneficial, and therefore indicated, in these patients remains uncertain. We retrospectively investigated early and late outcomes of BIMA grafting in patients aged ≥75 years.

METHODS AND RESULTS

We identified 460 patients aged ≥75 years from among 2,618 patients who underwent either single internal mammary artery (SIMA) grafting (n=293) or BIMA grafting (n=107). Early outcomes did not differ between the SIMA and BIMA patients (30-day mortality: 1.7% vs. 0%, P=0.39; sternal wound infection: 1.0% vs. 4.7%; P=0.057). Late outcomes, 10-year survival in particular, were improved in the BIMA group (36.6% vs. 48.1%, P=0.033). In the analysis of the results in propensity score-matched groups (196 patients in the SIMA group, 98 patients in the BIMA group), improved 10-year survival was documented in the BIMA group (34.8% vs. 47.6%, P=0.030). Cox proportional regression analysis showed SIMA usage (non-use of BIMA) to be a predictor for late mortality (hazard ratio: 0.65, 95% confidence interval: 0.43-0.98, P=0.042). We further compared outcomes between the total non-elderly patients (n=2,158) and total elderly patients (n=460). BIMA usage was similar, as was 30-day mortality (1.0% vs. 1.3%, respectively).

CONCLUSIONS

A survival advantage, with no increase in early mortality, can be expected from BIMA grafting in patients aged ≥75 years. (Circ J 2016; 80: 1756-1763).

A review of statin use in patients with acute coronary syndrome in Western and Japanese populations

Early high-dose statin therapy to reduce low-density lipoprotein cholesterol (LDL-C) is associated with improved cardiovascular outcomes in Western patients with stable coronary heart disease or acute coronary syndromes (ACS), but many patients remain undertreated and do not attain LDL-C treatment goals. Early statin therapy has also been shown to improve cardiovascular outcomes in Japanese patients with ACS, and pretreatment with high-dose statin prior to percutaneous coronary intervention has been shown to reduce cardiovascular events in these patients. As is the case in Western populations, many Japanese patients may be undertreated and a residual cardiovascular risk remains. While differences in treatment practice, dosing and genetic factors exist between Japan and Western countries, similarities are also evident when Japanese statin studies are compared with those performed in Western populations. With the increasing prevalence of cardiovascular risk factors in Japan, aggressive statin treatment may be beneficial in achieving optimal cardiovascular outcomes.

Impact of the clinical syntax score on 5-year clinical outcomes after sirolimus-eluting stents implantation

The SYNTAX score stratifies risk among drug-eluting stent-treated patients and is based on lesion characteristics alone. The Clinical SYNTAX Score (CSS) combines the SYNTAX score with age, ejection fraction, and creatinine clearance. We assessed its ability to stratify long-term outcomes in sirolimus-eluting stents (SES)-treated patients. Between August 2004 and March 2005, 249 patients were treated with SES. Clinical follow-up was evaluated at more than 5 years. The CSS was available for 206 patients. More than 5-year clinical follow-up data (mean 2114 ± 107 days) and CSS (range 1-322, mean 35.3 ± 49.9, median 17.5) were available for 201 patients. We divided these scores into tertiles: CSS-LOW ≤ 9.5, 9.5 < CSS-MID ≤ 28, and CSS-HIGH > 28. CSS-HIGH was associated with a higher death rate (CSS-LOW 9.0 %, CSS-MID 11.9 %, CSS-HIGH 41.8 %; log-rank p < 0.001) and major adverse cardiovascular events (MACE) (CSS-LOW 29.8 %, CSS-MID 35.8 %, CSS-HIGH 61.2 %; log-rank p = 0.004). Independent predictors for death were hemodialysis [hazard ratio (HR) 3.82; p < 0.001], age (HR 1.67; p = 0.003), ejection fraction (HR 0.98, p = 0.012) and CSS (HR 1.73, p = 0.028), and those for MACE were hemodialysis (HR 2.53, p = 0.002) and CSS (HR 1.40, p = 0.028). Areas under the curve for the SYNTAX score and CSS for death were 0.60 and 0.78 (p < 0.001), whereas those for MACE were 0.58 and 0.68 (p < 0.001), respectively. The CSS predicts long-term outcomes among SES-treated patients better than the SYNTAX score.

Bias in observational studies of prevalent users: lessons for comparative effectiveness research from a meta-analysis of statins

Randomized clinical trials (RCTs) are usually the preferred strategy with which to generate evidence of comparative effectiveness, but conducting an RCT is not always feasible. Though observational studies and RCTs often provide comparable estimates, the questioning of observational analyses has recently intensified because of randomized-observational discrepancies regarding the effect of postmenopausal hormone replacement therapy on coronary heart disease. Reanalyses of observational data that excluded prevalent users of hormone replacement therapy led to attenuated discrepancies, which begs the question of whether exclusion of prevalent users should be generally recommended. In the current study, the authors evaluated the effect of excluding prevalent users of statins in a meta-analysis of observational studies of persons with cardiovascular disease. The pooled, multivariate-adjusted mortality hazard ratio for statin use was 0.77 (95% confidence interval (CI): 0.65, 0.91) in 4 studies that compared incident users with nonusers, 0.70 (95% CI: 0.64, 0.78) in 13 studies that compared a combination of prevalent and incident users with nonusers, and 0.54 (95% CI: 0.45, 0.66) in 13 studies that compared prevalent users with nonusers. The corresponding hazard ratio from 18 RCTs was 0.84 (95% CI: 0.77, 0.91). It appears that the greater the proportion of prevalent statin users in observational studies, the larger the discrepancy between observational and randomized estimates.

Clinical significance of intensive lipid-lowering therapy using statins in patients with coronary artery disease: LDL-cholesterol: the lower, the better; is it true for Asians? (Pro)

Large clinical trials have elucidated that lipid-lowering therapy using statins reduces cardiovascular events in patients with coronary artery disease (CAD). The benefit of statin therapy is proportional to the achieved low-density lipoprotein cholesterol level (LDL-C) up to 70 mg/dl. On the basis of this evidence, the American Heart Association and American College of Cardiology offer an optimal LDL-C goal of <70 mg/dl for patients with a very high risk of CAD. In addition, with regard to acute coronary syndrome (ACS), which has a high risk for future cardiac events because of the presence of vulnerable plaque, intensive lipid-lowering therapy from the early stage is the standard treatment. On the other hand, the mechanism of inhibition of cardiac events by statins is thought to be predominantly based on stabilization of plaque, but research on the role of plaque regression is also advancing. The clinical significance of intensive lipid-lowering therapy using statins will be discussed from the following standpoints: (1) large-scale clinical trials around the world; (2) the relationship with plaque regression and stabilization; (3) the relationship with the diverse effects of statins; and (4) evidence generated from Japanese patients.

Effect of baseline glycemic level on long-term cardiovascular outcomes after coronary revascularization therapy in patients with type 2 diabetes mellitus treated with hypoglycemic agents

The present study evaluated the association between preoperative hemoglobin A1c (HbA1c) levels and cardiovascular outcomes in patients with type 2 diabetes mellitus (DM) treated with hypoglycemic agents and undergoing coronary revascularization. We conducted a multicenter registry of Japanese patients undergoing first elective coronary revascularization. The present study included 3,571 patients whose HbA1c value at the index hospitalization was available. Of the 3,571 patients, 2,067 did not have DM and 1,504 had type 2 DM. Of the patients with type 2 DM, 202 had a HbA1c level of <6% (very low HbA1c group [VLG]), 426 had a HbA1c level of > or =6% but <7% (low HbA1c group), 405 had a HbA1c level of '7% but <8% (intermediate HbA1c group), and 471 had a HbA1c level of > or =8% (high HbA1c group). The patients with type 2 DM treated with diet only were not included in the present study. The VLG had the lowest rate of freedom from major adverse cardiovascular events (MACE), a composite of cardiovascular death, myocardial infarction, and stroke. On multivariate analyses, the low HbA1c group had the lowest hazard ratio for MACE relative to those without DM (hazard ratio 1.13, 95% confidence interval 0.80 to 1.55). The VLG, intermediate HbA1c group, and high HbA1c group were significantly associated with an increased risk of MACE. On multivariate analyses of patients with DM using the low HbA1c group as a reference, a high HbA1c group level was significantly associated with an increased risk of MACE. The VLG and intermediate HbA1c group tended to be associated with an increased risk of MACE (VLG, hazard ratio 1.54, 95% confidence interval 0.98 to 2.40; intermediate HbA1c group, hazard ratio 1.44, 95% confidence interval 0.98 to 2.13). In conclusion, patients with type 2 DM treated with hypoglycemic agents and undergoing first elective coronary revascularization had significantly worse cardiovascular outcomes than patients without DM, except for patients with DM and a HbA1c of 6% to 7%. In the patients with DM, those with a HbA1c of 6% to 7% tended to have the lowest risk of MACE.

Comparison of case fatality rates for acute myocardial infarction in weekday vs weekend admissions in South Korea

BACKGROUND

According to recent reports, reduced weekend staffing in hospitals may lead to a lower intensity of management of patients with acute conditions such as acute myocardial infarction (AMI). The present study evaluated differences in the case fatality rate of Korean patients admitted with AMI on weekdays vs those admitted on weekends.

METHODS AND RESULTS

The dataset was constructed from the Korea National Health Insurance Claims Database. The study population was 97,466 patients who were admitted to a hospital in Korea from 2003 to 2007 with AMI. Patients admitted on weekends had a higher 30-day fatality rate (20.1% vs 17.3%) than did those admitted on weekdays. Differences in the 30-day fatality rate were significant after adjusting for baseline characteristics and the severity of disease (odds ratio (OR), 1.21; 95% confidence interval (CI), 1.16-1.26). However, the 30-day fatality rate was insignificantly different after additional adjustment for medical or invasive management (OR 1.05; 95%CI 0.99-1.11).

CONCLUSIONS

Differences in the case fatality rate of AMI patients admitted on weekdays and on weekends in Korea are caused by differences in the rate of performance of medical or invasive procedures.

Coronary risk factor profile and prognostic factors for young Japanese patients undergoing coronary revascularization

BACKGROUND

The prevalence of coronary artery disease (CAD) is increasing in young adults. Risk factor profiling will help to prevent heart attacks in young patients. This study aimed to analyze the risk factor profile and predictors of major cardiovascular events (MACE) in young CAD patients.

METHODS AND RESULTS

From the Coronary REvascularization Demonstrating Outcome study in the Kyoto (CREDO-Kyoto) registry of Japanese patients undergoing their first coronary revascularization, 6,320 patients with complete data for all variables for statistical analyses were divided into younger (< or =55 years; n=898; 14.3%) and older (>55 years; n=5,422; 85.7%) patients. The risk factors that were more prevalent in the younger patients than in the older patients included: male sex, body mass index of >25 kg/m(2), current smoker, family history of CAD, dyslipidemia and metabolic syndrome-like risk factor accumulation. Multivariate analyses revealed that chronic kidney disease (CKD) was the only significant predictor of MACE, the composite of cardiovascular death, myocardial infarction and cerebrovascular accident, in the younger patients. Importance of CKD as a prognostic factor was consistently shown by a multivariate analysis in the older patients.

CONCLUSIONS

Accumulation of multiple risk factors is prevalent and CKD is associated with MACE in young Japanese CAD patients.