Paradoxical impact of decreased low-density lipoprotein cholesterol level at baseline on the long-term prognosis in patients with acute coronary syndrome

The role of remnant cholesterol in patients with ST-segment elevation myocardial infarction

AIMS

Remnant cholesterol (RC) is the cholesterol content within triglyceride-rich lipoproteins. It promotes atherosclerotic cardiovascular disease beyond LDL cholesterol (LDL-C). The prognostic role of RC in patients with ST-segment elevation myocardial infarction (STEMI) is unknown. We aimed to estimate RC-related risk beyond LDL-C in patients with STEMI.

METHODS AND RESULTS

A total of 6602 consecutive patients with STEMI treated with primary percutaneous coronary intervention (PCI) from 1999 to 2016 were included. Remnant cholesterol was calculated as total cholesterol minus LDL-C minus HDL cholesterol. Adjusted Cox models were used to estimate the association between continuous RC levels and all-cause mortality, cardiovascular death, ischaemic stroke, and recurrent myocardial infarction (MI) at long-term (median follow-up of 6.0 years). Besides, discordance analyses were applied to examine the risk of the discordantly high RC (RC percentile rank minus LDL-C percentile rank > 10 units) compared with the discordantly low RC (LDL-C percentile rank minus RC percentile rank > 10 units). The concordance was defined as the percentile rank difference between RC and LDL-C ≤ 10 units. The median age of patients was 63 years [interquartile range (IQR) 54-72] and 74.8% were men. There were 2441, 1651, and 2510 patients in the discordantly low RC group, concordant group, and discordantly high RC group, respectively. All outcomes in the discordantly high RC group were higher than the other groups, and the event rate of all-cause mortality in this group was 31.87%. In the unadjusted analysis, the discordantly high RC was associated with increased all-cause mortality [hazard ratio (HR) 1.82, 95% confidence interval (CI) 1.63-2.04] and increased cardiovascular death (HR 1.79, 95% CI 1.55-2.06) compared with the discordantly low RC. In an adjusted model, RC was associated with higher all-cause mortality (HR 1.14, 95% CI 1.07-1.22). The discordantly high RC was associated with increased all-cause mortality (adjusted HR 1.55, 95% CI 1.37-1.75) and increased cardiovascular death (adjusted HR 1.47, 95% CI 1.25-1.72) compared with the discordantly low RC. There were no associations between RC and ischaemic stroke or recurrent MI.

CONCLUSION

In patients with STEMI treated with primary PCI, elevated RC levels beyond LDL-C and discordantly high RC were independently associated with increased all-cause mortality.

Elevated low-density lipoprotein cholesterol: An inverse marker of morbidity and mortality in patients with myocardial infarction

BACKGROUND

The incidence of atherosclerotic cardiovascular disease increases with levels of low-density lipoprotein cholesterol (LDL-C). Yet, a paradox may exist where lower LDL-C levels at myocardial infarction (MI) are associated with poorer prognoses.

OBJECTIVE

To assess the association between LDL-C levels at MI with risk factor burden and cause-specific outcomes.

METHODS

Statin-naive patients hospitalized for a first MI and registered in SWEDEHEART were included. Data were linked to Swedish registers. Primary outcomes were all-cause mortality and nonfatal MI. Associations between LDL-C and outcomes were assessed using adjusted proportional hazards models.

RESULTS

Among 63,168 patients (median age, 66 years), the median LDL-C level was 3.0 mmol/L (interquartile range 2.4-3.6). Patient age and comorbidities increased as LDL-C decreased. During a median follow-up of 4.5 years, 10,236 patients died, and 4973 had nonfatal MI. Patients with the highest LDL-C had a lower risk of mortality (hazard ratio [HR] 0.75; 95% confidence interval [CI] 0.71-0.80). The risk of hospitalization for pneumonia, hip fracture, chronic obstructive pulmonary disease, and new cancer diagnosis was lower with higher LDL-C (HR range, 0.40-0.81). Patients with the highest LDL-C had a greater risk of recurrent MI (HR 1.16; 95% CI 1.07-1.26).

CONCLUSIONS

Patients with the highest LDL-C levels at MI had the lowest incidence of mortality and morbidity. This seems to reflect lower age at MI, less underlying morbidities, paired with the modifiability of LDL-C. However, supporting the causal association between LDL-C and ischemic heart disease, elevated LDL-C was simultaneously associated with an increased risk of nonfatal MI.

Time-varying effect of postoperative cholesterol profile on long-term outcomes of isolated coronary artery bypass graft surgery

BACKGROUND

Controlling cholesterol levels is one of the primary goals of preventing atherosclerotic plaque progression in patients undergoing coronary artery bypass graft (CABG) surgery. This study aimed to investigate the impact of serum cholesterol profile at multiple time points following isolated CABG surgery on long-term patient outcomes.

METHOD

This retrospective cohort study was conducted on the admission and follow-up data of isolated CABG patients from the Tehran Heart Center registry between 2009 and 2016. The association of low-density lipoprotein (LDL), high-density lipoprotein (HDL), and their ratio as an atherogenic index with major adverse cardiac and cerebrovascular events (MACCE) and all-cause mortality were evaluated using time-varying survival analysis methods.

RESULT

A total of 18657 patients were included in this analysis. After adjusting for known confounding factors, no significant difference in all-cause mortality and MACCE was observed at different LDL levels. The incidence of acute coronary syndrome (ACS) in patients with LDL > 100 mg/dl and LDL < 50 mg/dl was significantly higher than in the control group (P-value = 0.004 and 0.04, respectively). The incidence of cerebrovascular accidents (CVA) at LDL > 100 mg/dl was also significantly higher compared to the control group (P -value = 0.033). Lower HDL levels were significantly associated with a higher MACCE (P -value < 0.001), all-cause mortality (P -value < 0.001), ACS (P -value = 0.00), and CVA (P -value = 0.014). The atherogenic index was also directly related to MACCE and all its components (all P-values < 0.001).

CONCLUSION

LDL/HDL ratio is suggested as a better marker for secondary prevention goals compared to LDL alone in patients undergoing CABG surgery.

The prognostic role of the low and very low baseline LDL-C level in outcomes of patients with cardiac revascularization; comparative registry-based cohort design

BACKGROUND

Although low-density lipoprotein-cholesterol (LDL-C) level is considered one of the main prognostic factors in patients with coronary artery bypass grafting (CABG), the question about "the lower the better" is still unanswered. We aimed to evaluate and compare the outcomes of patients with CABG and low or very low baseline LDL-C, regardless of statin usage.

METHODS

In this registry-based cohort study, 10,218 patients with low/very low (70-100 and ≤ 70 mg/dL) baseline LDL-C who underwent isolated and the first-time CABG without known previous history of cardio-cerebrovascular events, were included and compared. The median follow-up was 73.33 (72.15-74.51) months. Primary outcomes were all-cause mortality and major adverse cardio-cerebrovascular events (MACCE) (consisted of all-cause mortality, acute coronary syndrome, stroke or transient ischemic attack, and the need for repeat revascularization [percutaneous coronary intervention or redo-CABG]). Cox regression analyses before and after the propensity score matching (PSM) model were applied to evaluate and compare outcomes.

RESULTS

The mean age of the study population was 66.17 ± 9.98 years old and 2506 (24.5%) were women. Diabetes mellitus and a history of cigarette smoking were significantly higher in the very low LDL group (P-value ≤ 0.001). In Cox regression analyses before applying PSM model, both all-cause mortality (14.2% vs. 11.9%, P-value = 0.004 and MACCE (26.0% vs. 23.6%, P-value = 0.006) were significantly higher in the very low LDL group compared to low LDL. However, these results were no longer significant after applying the PSM model (all-cause mortality HR: 1.115 [95% CI: 0.986-1.262], P = 0.083 and MACCE HR: 1.077 [95%CI: 0.984-1.177], P = 0.095). The sensitivity analysis to remove the statin effect demonstrated that very low LDL-C level was correlated to higher risk of all-cause mortality in both unmatched and PSM analyses.

CONCLUSION

Very low serum LDL-C levels (≤ 70 mg/dl) could increase long-term all-cause mortality and cardiovascular events in patients who have undergone isolated CABG.

Evaluation of the Association between Low-Density Lipoprotein (LDL) and All-Cause Mortality in Geriatric Patients with Hip Fractures: A Prospective Cohort Study of 339 Patients

BACKGROUND

Many factors affect the prognosis of hip fractures in the elderly. Some studies have suggested a direct or indirect association among serum lipid levels, osteoporosis, and hip fracture risk. LDL levels were found to have a statistically significant nonlinear U-shaped relationship with hip fracture risk. However, the relationship between serum LDL levels and the prognosis of patients with hip fractures remains unclear. Therefore, in this study, we assessed the influence of serum LDL levels on patient mortality over a long-term follow-up period.

METHODS

Elderly patients with hip fractures were screened between January 2015 and September 2019, and their demographic and clinical characteristics were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between LDL levels and mortality. Analyses were performed using Empower Stats and R software.

RESULTS

Overall, 339 patients with a mean follow-up period of 34.17 months were included in this study. Ninety-nine patients (29.20%) died due to all-cause mortality. Linear multivariate Cox regression models showed that LDL levels were associated with mortality (HR = 0.69, 95%CI: 0.53, 0.91, p = 0.0085) after adjusting for confounding factors. However, the linear association was unstable, and nonlinearity was identified. An LDL concentration of 2.31 mmol/L was defined as the inflection point for prediction. A LDL level < 2.31 mmol/L was associated with mortality (HR = 0.42, 95%CI: 0.25, 0.69, p = 0.0006), whereas LDL > 2.31 mmol/L was not a risk factor for mortality (HR = 1.06, 95%CI: 0.70, 1.63, p = 0.7722).

CONCLUSIONS

The preoperative LDL level was nonlinearly associated with mortality in elderly patients with hip fractures, and the LDL level was a risk indicator of mortality. Furthermore, 2.31 mmol/L could be considered a predictor cut-off for risk.

Low-density lipoprotein cholesterol in oldest old with acute myocardial infarction: Is lower the better?

BACKGROUND

the relationship between low-density lipoprotein cholesterol (LDL-C) and adverse outcomes among the older people remains controversial.

OBJECTIVE

to further clarify the association between admission LDL-C levels and cardiovascular mortality (CVM) among oldest old individuals (≥80 years) with acute myocardial infarction (AMI).

DESIGN

a prospective cohort study.

SETTING

two-centre.

SUBJECTS

a consecutive sample of 1,224 oldest old individuals with AMI admitted to Beijing FuWai and Shenzhen FuWai hospitals.

METHODS

all individuals were subdivided according to baseline LDL-C levels (<1.8, 1.8-2.6 and ≥ 2.6 mmol/l) and further stratified by high-sensitivity C-reactive protein (hsCRP) concentrations (<10 and ≥10 mg/l). The primary outcome was CVM. The time from admission to the occurrence of CVM or the last follow-up was analysed in Kaplan-Meier and Cox analyses.

RESULTS

the median age of the overall population was 82 years. During an average of 24.5 months' follow-up, 299 cardiovascular deaths occurred. Kaplan-Meier analysis showed that LDL-C < 1.8 mmol/l group had the highest CVM among oldest old individuals with AMI. Multivariate Cox regression analysis further revealed that compared with those with LDL-C levels <1.8 mmol/l, subjects with LDL-C levels ≥2.6 mmol/l (hazard ratio: 0.67, 95% confidence interval: 0.46-0.98) had significantly lower risk of CVM, especially in those with high hsCRP levels. Moreover, when categorising according to LDL-C and hsCRP together, data showed that individuals with low LDL-C and high hsCRP levels had the highest CVM.

CONCLUSIONS

LDL-C < 1.8 mmol/l was associated with a high CVM after AMI in oldest old individuals, especially when combined with high hsCRP levels, which may need to be confirmed by randomised controlled trials.

Impact of hyperuricemia on coronary blood flow and in-hospital mortality in patients with acute myocardial infarction undergoing percutaneous coronary intervention

BACKGROUND

Although serum uric acid (UA) is considered as a risk factor for cardiovascular disease, few data exist regarding the relationship between hyperuricemia, coronary blood flow, and subsequent outcome in patients with acute myocardial infarction (AMI). The purpose of our study is to assess whether hyperuricemia is associated with suboptimal coronary flow and increased risk of mortality in patients with AMI after percutaneous coronary intervention (PCI).

METHODS

Using the Rural AMI registry data, 989 consecutive patients with AMI who underwent emergent PCI and had UA measurement at admission were analyzed. We defined hyperuricemia as serum UA ≥7.0 mg/dL in men and ≥ 6.0 mg/dL in women. The primary endpoint was suboptimal coronary flow, defined as post PCI Thrombosis In Myocardial Infarction flow grade ≤ 2. The secondary outcome was in-hospital mortality.

RESULTS

Hyperuricemia was found in 249 (25.2%) patients. Patients with hyperuricemia were more often complicated with cardiogenic shock compared with those without (16.9% vs. 7.4%, p < 0.001). In addition, the median high-sensitivity C-reactive protein was significantly higher in patients with hyperuricemia (0.18 mg/dL; IQR, 0.09-0.71 mg/dL) than in those without (0.14 mg/dL; IQR, 0.07-0.41 mg/dL, p < 0.05). Under these conditions, the prevalence of suboptimal coronary flow after PCI (17.3% vs. 10.1%, p < 0.05) and in-hospital mortality (10.8% vs. 3.6%, p < 0.001) were significantly higher in patients with hyperuricemia compared with those without. Multivariable logistic regression analysis revealed that hyperuricemia was significantly associated with suboptimal coronary flow [odds ratio (OR), 1.60; 95% confidence interval (CI), 1.02-2.49; p < 0.05] and in-hospital mortality (OR, 2.08; 95% CI, 1.05-4.12; p < 0.05).

CONCLUSIONS

Assessment of serum UA upon admission provides useful information for predicting suboptimal coronary flow and in-hospital mortality in patients with AMI undergoing PCI.

Paradoxical Association Between Baseline Apolipoprotein B and Prognosis in Coronary Artery Disease: A 36,460 Chinese Cohort Study

Background

Apolipoprotein B (ApoB) and low-density lipoprotein cholesterol (LDL-C) were identified targets for blood lipid management among coronary artery disease (CAD) patients. However, previous studies reported an inverse correlation between baseline LDL-C concentration and clinical outcomes. This study aims to explore the definite association between baseline ApoB and long-term prognosis.

Methods

A total of 36,460 CAD patients admitted to Guangdong Provincial People's Hospital were enrolled and categorized into two groups: high ApoB (≥65 mg/dL) group and low ApoB (<65 mg/dL) group. The association between baseline ApoB and long-term all-cause mortality was evaluated by the Kaplan-Meier method, Cox regression analyses and restricted cubic splines.

Results

The overall mortality was 12.49% (n = 4,554) over a median follow-up period of 5.01 years. Patients with low baseline ApoB levels were paradoxically more likely to get a worse prognosis. There was no obvious difference in risk of long-term all-cause mortality when only adjusted for age, gender, and comorbidity (aHR: 1.07, 95% CI: 0.99–1.16). When CONUT and total bilirubin were adjusted, the risk of long-term all-cause mortality would reduce in the low-ApoB (<65 mg/dL) group (aHR: 0.86, 95% CI: 0.78–0.96). In the fully covariable-adjusted model, patients in the ApoB <65 mg/d group had a 10.00% lower risk of long-term all-cause mortality comparing to patients with ApoB ≥65 mg/dL (aHR: 0.90; 95% CI:0.81–0.99).

Conclusion

This study found a paradoxical association between baseline ApoB and long-term all-cause mortality. Malnutrition and bilirubin mainly mediate the ApoB paradox. Increased ApoB concentration remained linearly associated with an increased risk of long-term all-cause mortality.

C Deletion at the re74650330 Locus of the SLC39A8 Gene (rs74650330) Increases the Risk of Coronary Artery Disease in Individuals with Low-Density Lipoprotein Cholesterol Levels

Background: Genetic variants of the SLC39A8 gene are associated with several cardiovascular disease risk factors, including body mass index, systolic blood pressure (SBP), diastolic blood pressure (DBP), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-density lipoprotein cholesterol (HDL-C) levels. The present study aimed to investigate the association between the SLC39A8 SNPs rs13107325 and rs74650330 and CAD in the Han population in Jiangsu (China). Methods: Genotyping of these SNPs was performed in 258 patients with CAD and 170 healthy controls using the base-quenched probe technique. The association between the alleles of the rs74650330 locus and blood lipid and glucose profiles was investigated. Receiver operating characteristic (ROC) curve analysis was used to quantify the optimal thresholds for lipid and FBG levels and the risk factors for CAD were estimated by logistic regression analysis. Results: The rs13107325 polymorphism was not found in the 428 Chinese individuals enrolled in the current study. For rs74650330, individuals harboring the C allele had significantly higher HDL levels than those without this allele in the control group (p = 0.039), while the opposite was true for low-density lipoprotein cholesterol (LDL-C) levels (p = 0.046). Further analysis indicated that when LDL-C levels were lower than 2.365 mmol/L, subjects with C/del and del/del had a 7.293-fold increased risk of CAD compared with that of controls without the mutation (odds ratio: 7.293; 95% confidence interval: 0.953-55.79). Conclusions: The susceptibility of SLC39A8 polymorphisms to CAD were studied and revealed a possible role for the deletion variant of rs74650330 in increasing the risk of CAD among the Chinese Han population.

Malnutrition affects cholesterol paradox in coronary artery disease: a 41,229 Chinese cohort study

BACKGROUND

Several studies have found that a low baseline low -density lipoprotein cholesterol (LDL-C) concentration was associated with poor prognosis in patients with acute coronary syndrome (ACS), which is called the "cholesterol paradox". Low LDL-C concentration may reflect underlying malnutrition, which was strongly associated with increased mortality. The aim of this study was to investigate the cholesterol paradox in patients with CAD and the effects of malnutrition.

METHOD

A total of 41,229 CAD patients admitted to Guangdong Provincial People's Hospital in China were included in this study from January 2007 to December 2018 and divided into two groups (LDL-C < 1.8 mmol/L, n = 4863; LDL-C ≥ 1.8 mmol/L, n = 36,366). The Kaplan-Meier method and Cox regression analyses were used to assess the association between LDL-C levels and long-term all-cause mortality and the effect of malnutrition.

RESULT

In this real-world cohort (mean age 62.9 years; 74.9% male), there were 5257 cases of all-cause death during a median follow-up of 5.20 years [interquartile range (IQR): 3.05-7.78 years]. Kaplan-Meier analysis showed that low LDL-C levels were associated with a worse prognosis. After adjusting for baseline confounders (e.g., age, sex and comorbidities, etc.), multivariate Cox regression analysis revealed that a low LDL-C level (< 1.8 mmol/L) was not significantly associated with all-cause mortality (adjusted HR, 1.04; 95% CI, 0.96-1.24). After adjustment for nutritional status, the risk of all-cause mortality in patients with low LDL-C levels decreased (adjusted HR, 0.90; 95% CI, 0.83-0.98). In the final multivariate Cox model, a low LDL-C level was related to better prognosis (adjusted HR, 0.91; 95% CI, 0.84-0.99).

CONCLUSION

This study demonstrated that the cholesterol paradox existed in CAD patients but disappeared after accounting for the effects of malnutrition.

Comparison of Door-to-Balloon Time and 30-Day Mortality According to Symptom Presentation in Patients With Acute Myocardial Infarction

Background: We hypothesized that symptom presentation in patients with acute myocardial infarction (AMI) may affect their management and subsequent outcome. Methods and Results: Using Rural AMI Registry data, 1,337 consecutive patients with AMI who underwent percutaneous coronary intervention were analyzed. Typical symptoms were defined as any symptoms of chest pain or pressure due to myocardial ischemia. We considered the specific symptoms of dyspnea, nausea, or vomiting as atypical symptoms. The primary outcome was 30-day mortality. There were 150 (11.2%) and 1,187 (88.8%) patients who presented with atypical and typical symptoms, respectively. Those who presented with atypical symptoms were significantly older (mean [±SD] age 74±12 vs. 68±13 years; P<0.001) and had a higher Killip class (46.7% vs. 21.8%; P<0.001) than patients presenting with typical symptoms. The prevalence of door-to-balloon time of ≤90 min was significantly lower in patients with atypical than typical symptoms (40.0% vs. 66.3%; P<0.001). At 30 days, there were 55 incidents of all-cause death. Multivariate Cox proportional hazards regression analysis revealed that symptom presentation was associated with 30-day mortality (hazard ratio 2.33; 95% confidence interval 1.20-4.38; P<0.05). Conclusions: Atypical symptoms in patients with AMI are less likely to lead to timely reperfusion and are associated with increased risk of 30-day mortality.

Impact of high-dose statin on cardiovascular outcomes in real-world patients with ST-elevation acute myocardial infarction

Little is known about the impact of a high-dose statin on cardiovascular outcomes after ST-elevation acute myocardial infarction (STEMI) in real-world Japanese patients. Between July 2011 and June 2017, 1110 consecutive STEMI patients underwent primary percutaneous coronary intervention at our hospital and were discharged. A high-dose statin was administered in 117 patients (10.5%) and non-high-dose statin was administered in 947 patients (85.3%). The low-density lipoprotein cholesterol level was significantly higher in the high-dose statin group at admission (129.8 ± 44.9 vs. 110.4 ± 32.7, p < 0.0001), but the levels were not significantly different at follow-up (86.7 ± 25.7 vs. 85.0 ± 25.0, p = 0.52). The cumulative 2-year incidence of a composite of cardiac death, myocardial infarction, ischemic stroke, and any unplanned coronary revascularization was significantly lower in the high-dose statin group (6.2% vs. 16.9%, log-rank p = 0.004). Propensity score matched analysis indicated similar results. Among the types of coronary revascularization, a high-dose statin was significantly correlated with a lower rate of de novo lesion revascularization (hazard ratio 0.31; 95% confidence interval 0.08-0.83; p = 0.02). The results of our analyses indicate that administration of a high-dose statin may result in better cardiovascular outcomes after STEMI mainly by reducing the rate of revascularization for de novo lesions regardless of the achieved low-density lipoprotein cholesterol level in real-world patients.

Impact of concomitant peripheral artery disease on contrast-induced acute kidney injury and mortality in patients with acute coronary syndrome after percutaneous coronary intervention

Subclinical peripheral artery disease (PAD) might be associated with pathophysiology of contrast-induced acute kidney injury (CI-AKI). We hypothesized that concomitant PAD in patients with the acute coronary syndrome (ACS) would represent a high-risk subgroup with a greater incidence of CI-AKI, both of which lead to higher mortality after percutaneous coronary intervention (PCI). Six hundred and seventy-five consecutive patients with ACS who underwent PCI and examination of ankle-brachial index (ABI) were analyzed retrospectively. The presence of PAD was defined as an ABI < 0.9. We investigated whether (1) PAD was an independent predictor of CI-AKI (≥ 0.3 mg/dL or ≥ 50% relative increase in serum creatinine within 48 h after PCI) and (2) PAD and CI-AKI were independently associated with long-term mortality. Of the 675 patients with ACS, 114 (17%) exhibited PAD. The incidence of CI-AKI was significantly higher in PAD patients, compared with the remaining patients (12% vs. 4%, p < 0.001). Multivariate logistic regression analysis revealed that the presence of PAD was an independent predictor for the development of CI-AKI [odds ratio 2.50, 95% confidence interval (CI) 1.07-5.73, p < 0.05]. During the median 4-year follow-up, there were 65 incidents of all-cause death. In the multivariate Cox proportional hazard regression analysis, the presence of PAD [hazard ratio (HR) 2.08, 95% CI 1.17-3.65, p < 0.05] and CI-AKI (HR 2.23, 95% CI 1.08-4.26, p < 0.05) were associated with an increased risk of all-cause mortality. Assessment of ABI provides useful information for predicting CI-AKI and long-term mortality in patients with ACS after PCI.