Lipid Paradox in Statin-Naïve Acute Ischemic Stroke But Not Hemorrhagic Stroke

Low-Density Lipoprotein Cholesterol to Triglyceride Ratio and Clinical Outcomes after Acute Ischaemic Stroke or Transient Ischaemic Attack

AIMS

Studies showed that low-density lipoprotein cholesterol (LDL-C) to triglyceride (TG) ratio could be used as a predictive parameter of low-density lipoprotein oxidation in vivo and the level of small dense LDL-C. However, whether LDL-C/TG ratio is associated with stroke prognosis remains unclear. We investigated the associations of LDL-C/TG ratio with outcomes in patients with acute ischaemic stroke (AIS) or transient ischaemic attacks (TIA) and explored whether it produced more predictive value than LDL-C and TG.

METHODS

Data were derived from the Third China National Stroke Registry (CNSR-III). Multivariable Cox regression for stroke recurrence, composite vascular events and all-cause death and logistic regression for the poor functional outcome (modified Rankin Scale score 3-6) were used.

RESULTS

A total of 14123 patients were included. After adjusting for confounding factors, quartile 4 of LDL-C/TG ratio was associated with an increased risk of recurrent stroke (hazard ratio [HR], 1.27; 95% confidence interval [CI], 1.03-1.56), composite vascular events (HR,1.23; 95% CI, 1.00-1.52), death (HR,1.70; 95% CI, 1.13-2.54) and poor functional outcome (odds ratio, 1.34; 95% CI, 1.12-1.61) at 3 months follow-up compared with quartile 1. We also found that quartile 4 of LDL-C and TG was positively and negatively associated with poor functional outcome at 3 months, respectively. LDL-C/TG ratio performed better than LDL-C or TG in predicting clinical outcomes.

CONCLUSIONS

LDL-C/TG ratio was associated with the risk of stroke recurrence, composite vascular events, death and poor functional outcome in patients with AIS or TIA.

Differential impacts of admission LDL-cholesterol on early vascular outcomes by ischemic stroke subtypes

BACKGROUND

Because ischemic stroke is heterogeneous, the associations between low-density lipoprotein (LDL)-cholesterol levels and early vascular outcomes might be different according to the stroke subtype in acute ischemic stroke patients.

METHODS

This study was an analysis of a prospective, multicenter, stroke registry. Acute ischemic stroke patients previously not treated with statins were included. Admission LDL-cholesterol levels were divided into 7 groups at 20 mg/dl intervals for comparison. The primary early vascular outcome was a composite of stroke, myocardial infarction (MI) and all-cause mortality within 3 months.

RESULTS

A total of 38,531 patients (age, 68.5 ± 12.8 yrs; male, 59.6%) were analyzed for this study. The 3-month cumulative incidences of the composite of stroke, MI, and all-cause mortality significantly differed among the LDL-cholesterol level groups, with the highest event rate (11.11%) in the lowest LDL-cholesterol group (<70 mg/dl). After adjustment, the U-shaped associations of LDL-cholesterol levels with primary outcome and all-cause mortality were observed. For the stroke subtypes, there were substantial interactions between the LDL-cholesterol groups and stroke subtype and all-cause mortality (Pinteraction=0.07). Different patterns, with higher risks of all-cause mortality in the lower LDL-cholesterol in the large artery atherosclerosis subtype (adjusted hazard ratio [aHR] 1.29, 95% confidence interval [CI] 0.98-1.69), but in the higher LDL-cholesterol in the cardioembolism subtype (aHR 1.71 95% CI [1.28-2.29]), were observed among stroke subtypes.

CONCLUSION

We found that there were differential associations of admission LDL-cholesterol levels with all-cause mortality within 3 months among stroke subtypes. These results suggest that admission LDL-cholesterol and early vascular outcomes had complex relationships in patients with ischemic stroke according to the stroke subtypes.

Admission LDL-cholesterol, statin pretreatment and early outcomes in acute ischemic stroke

BACKGROUND

Lipid paradox of low LDL-C may cause physicians to be reluctant to use statins in acute ischemic stroke (AIS) patients with low LDL-C levels at admission.

OBJECTIVE

This study investigated the association between LDL-C levels and early vascular outcomes and assessed the potential interaction effect between LDL-C and statin pretreatment on early outcomes.

PATIENTS AND METHODS

This was a study of a prospective, multicenter, registry of AIS patients with admission LDL-C. The subjects were divided into 3 groups according to LDL-C levels: low LDL-C (≤100 mg/dL); intermediate LDL-C (>100, <130 mg/dL); and high LDL-C (≥130 mg/dL). The primary early vascular outcome was a composite of stroke (ischemic or hemorrhagic), myocardial infarction and all-cause mortality within 3 months. The associations of LDL-C levels as a continuous variable and the risks of primary outcome using Cox proportional hazards models with restricted cubic splines were explored.

RESULTS

A total of 32,505 patients (age, 69 ± 12; male, 58.6%) were analyzed. The 3 groups showed significant differences in the 3-month primary outcome, with highest events in the low LDL-C group; after adjustment, no significant associations with the 3-month primary outcome remained. U-shaped nonlinear relationships of LDL-C levels with the 3-month primary outcome were observed (Pnon-linearity<0.001), with substantial relationships in the no pretreatment subgroup.

CONCLUSIONS

The relationships between admission LDL-C levels and early outcomes are complex but appear to be paradoxical in patients with low LDL-C and no statin pretreatment. The results suggest that statin pretreatment might offset the paradoxical response of low LDL-C on early vascular outcomes. Further study would be warranted.

Stroke and dyslipidaemia in Africa: a meta-analysis of case-control studies

INTRODUCTION

Stroke is an acute neurological disorder characterized by an abrupt reduction in blood flow to the brain, spinal cord, or retina. There is a complex relationship between stroke and dyslipidaemia. The objective of the study was to determine the likelihood of dyslipidaemia in African stroke patients.

METHODS AND RESULTS

This study is a systematic review and meta-analysis of case-control studies to determine the odds ratio of dyslipidaemia among stroke patients in Africa. It followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The sources of data included Google Scholar, PubMed, SCOPUS, African Journal Online (AJOL), Research Square, SciELO, and medRxiv databases. The case-control studies eligible were conducted in Africa. The meta-analysis was carried out with Meta XL version 5.3, using the random effect model.

RESULTS

Ten studies met the eligibility criteria and the total sample size was 9599. The odds ratio of dyslipidaemia in all stroke cases in Africa was 1.61 (95% CI: 1.28-2.03) while that of ischaemic stroke and haemorrhagic stroke are 1.27 (0.54-2.98) and 1.71 (1.43-2.05) respectively.

CONCLUSION

Although not particularly substantial, there is an association between dyslipidaemia and stroke in Africa.

Suboptimal lipid management in patients with acute ischemic stroke

OBJECTIVE

Lipid-lowering drugs are among the most widely used drugs in cardiovascular prevention. Statins are often abandoned due to side effects, or under dosed, leading to unreached LDL-cholesterol goals and increased occurrence of cardiovascular events.

METHODS

We included hospitalized patients with an ischemic stroke or transient ischemic attack. Of 92 patients, low density lipoprotein cholesterol (LDL-C) levels and lipid lowering therapy at admission and discharge were assessed. Based on their cardiovascular risk before the current event according to the most recent European guidelines, LDL-C targets were determined. Low, moderate, high and very high risk corresponded with LDL-C targets below 116, 100, 70 and 55 mg/dL respectively.

RESULTS

Before current event, 59 (64%) were very high, 21 (23%) high, 11 (12%) moderate and 1 low risk patients and eight patients were treated with low, 23 moderate, and 21 high intensity lipid-lowering therapy. Upon admission, 75 patients had insufficiently managed LDL-cholesterol levels, yet 39 of them were taking lipid lowering therapy. Only eight of the 21 patients on high intensity lipid lowering therapy reached their LDL-C target. During hospitalization 40 patients were switched to a high-intensity statin. Thirty-three patients switched from no treatment or a lower-intensity to a moderate-intensity lipid lowering therapy. Three were dismissed with low-intensity lipid lowering therapy, and five in association with Ezetimibe. Three patients had documented statin-intolerance.

CONCLUSION

In this study, LDL-cholesterol was insufficiently managed according to international guidelines for prevention of ischemic stroke. Further optimization of lipid management in primary and secondary prevention and the use of higher intensity lipid lowering therapy in clinical practice is mandatory.

Age Stratification and Stroke Severity in the Telestroke Network

BACKGROUND

Age is one of the most important risk factors for stroke, and an estimated 75% of strokes occur in people 65 years old and above. Adults > 75 years of age experience more hospitalizations and higher mortality. In this study, we aimed to investigate how age and various clinical risk factors affect acute ischemic stroke (AIS) severity in two age categories.

METHODS

This retrospective data analysis study was conducted using data collected from the PRISMA Health Stroke Registry between June 2010 and July 2016. Baseline clinical and demographic data were analyzed for 65-74-year-old patients and those ≥ 75 years of age. This study aimed to investigate risk factors associated with stroke severity in these two age categories of AIS patients treated in telestroke settings.

RESULTS

An adjusted multivariate analysis showed that the acute ischemic stroke (AIS) population of 65-74-year-old patients experiencing heart failure (odds ratio (OR) = 4.398, 95% CI = 3.912-494.613, p = 0.002) and elevated high-density lipoprotein (HDL) levels (OR = 1.066, 95% CI = 1.009-1.126, p = 0.024) trended towards worsening neurological function, while patients experiencing obesity (OR = 0.177, 95% CI = 0.041-0.760, p = 0.020) exhibited improved neurological functions. For the patients ≥ 75 years of age, direct admission (OR = 0.270, 95% CI = 0.085-0.856, p = 0.026) was associated with improved functions.

CONCLUSIONS

Heart failure and elevated HDL levels were significantly associated with worsening neurologic functions in patients aged 65-74. Obese patients and individuals ≥ 75 years of age who were directly admitted were most likely to exhibit improving neurological functions.

Impact of Traditional and Non-Traditional Lipid Parameters on Outcomes after Intravenous Thrombolysis in Acute Ischemic Stroke

Contradicting evidence exists regarding the role of lipids in outcomes following intravenous (IV) thrombolysis with tissue plasminogen activator (tPA). Restricted cubic spline curves and adjusted logistic regression were used to evaluate associations of low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and LDL-C/HDL-C ratio with poor functional outcome, symptomatic intracranial hemorrhage (SICH) and 90-day mortality, among 1004 acute ischemic stroke (AIS) patients who received IV tPA in a comprehensive stroke center. Quartile (Q) 1, Q2 and Q3 of HDL-C were associated with increased odds of poor functional outcome (adjusted odds ratio (adjOR) 1.66, 95% CI 1.06-2.60, p = 0.028, adjOR 1.63, 95% CI 1.05-2.53, p = 0.027, adjOR 1.56, 95% CI 1.01-2.44, p = 0.048) compared to Q4. Q2 and Q4 of non-HDL-C were associated with increased odds of SICH (adjOR 4.28, 95% CI 1.36-18.90, p = 0.025, adjOR 5.17, 95% CI 1.64-22.81, p = 0.011) compared to Q3. Q1 and Q2 of LDL-C was associated with increased odds of mortality (adjOR 2.57, 95% CI 1.27-5.57, p = 0.011 and adjOR 2.28, 95% CI 1.10-5.02, p = 0.032) compared to Q3. In AIS patients who received IV tPA, low LDL-C was associated with increased odds of mortality while HDL-C may be protective against poor functional outcome.

Quantitative collateral score for the prediction of clinical outcomes in stroke patients: Better than visual grading

Objectives

To identify preoperative prognostic factors for acute ischemic stroke (AIS) patients receiving mechanical thrombectomy (MT) and compare the performance of quantitative collateral score (qCS) and visual collateral score (vCS) in outcome prediction.

Methods

Fifty-five patients with AIS receiving MT were retrospectively enrolled. qCS was defined as the percentage of the volume of collaterals of both hemispheres. Based on the dichotomous outcome assessed using a 90-day modified Rankin Scale (mRS), we compared qCS, vCS, age, sex, National Institute of Health stroke scale score, etiological subtype, platelet count, international normalized ratio, glucose levels, and low-density lipoprotein cholesterol (LDL-C) levels between favorable and unfavorable outcome groups. Logistic regression analysis was performed to determine the effect on the clinical outcome. The discriminatory power of qCS, vCS, and their combination with cofounders for determining favorable outcomes was tested with the area under the receiver-operating characteristic curve (AUC).

Results

vCS, qCS, LDL-C, and age could all predict clinical outcomes. qCS is superior over vCS in predicting favorable outcomes with a relatively higher AUC value (qCS vs. vCS: 0.81 vs. 0.74) and a higher sensitivity rate (qCS vs. vCS: 72.7% vs. 40.9%). The prediction power of qCS + LDL-C + age was best with an AUC value of 0.91, but the accuracy was just increased slightly compared to that of qCS alone.

Conclusion

Collateral scores, LDL-C and age were independent prognostic predictors for patients with AIS receiving MT; qCS was a better predictor than vCS. Furthermore, qCS + LDL-C + age offers a strong prognostic prediction power and qCS alone was another good choice for predicting clinical outcome.

Fatty Acids and Lipid Paradox-Neuroprotective Biomarkers in Ischemic Stroke

Stroke is the primary cause of death and disability worldwide, with ischemic stroke up to 80% of the total cases. Lipid profile was established as a major risk factor for stroke, but recent studies show a paradoxical relationship between serum values and the outcome of stroke patients. Our study aims to analyze the impact of the classic extended lipid profile, including fatty acids as potential neuroprotective biomarkers for the outcome of ischemic stroke patients. We included 298 patients and collected clinical, paraclinical, and outcome parameters. We used a method consisting of high-performance liquid chromatography coupled with mass spectrometry to quantify serum fatty acids. We observed a negative correlation between National Institutes of Health Stroke Scale (NIHSS) at admission and total cholesterol (p = 0.040; r = −0.120), respectively triglycerides (p = 0.041; r = −0.122). The eicosapentaenoic to arachidonic acid ratio has a negative correlation, while the docosahexaenoic to eicosapentaenoic acid ratio positively correlates with all the prognostic parameters, showing a potential neuroprotective role for eicosapentaenoic acid in preventing severe ischemic stroke. The impact of the lipid profile paradox and the dependency relationship with the fatty acids represent a significant predictive factor for the functional and disability prognostic of ischemic stroke patients.

Role of dyslipidemia in ischemic stroke patients treated in the telestroke network

PURPOSE

The relationship between the telestroke technology and clinical risk factors in a dysplipidemic ischemic stroke population and neurologic outcomes is not fully understood. This issue was investigated in this study.

PATIENTS AND METHODS

We analyzed retrospective data collected from a regional stroke registry to identify demographic and clinical risk factors in patients with improving (NIHSS ​≤ ​7) or worsening (NIHSS ​> ​7) neurologic outcome in dyslipidemic ischemic stroke population. We used logistic multivariate models to identify independent predictors of improving or worsening outcome based on dyslipidemia disease status in ischemic stroke patients.

RESULTS

In the adjusted analysis for dyslipidemic ischemic stroke population, cholesterol reducer use (odd ratio; [OR] ​= ​0.393, 95% confidence interval [CI], 0.176-0.879, P ​= ​0.023) and direct admission (OR ​= ​0.435, 95% CI, 0.199-0.953, P ​= ​0.037) were more likely to be associated with neurologic improvement and no clinical or demographic factors were associated with poor neurologic outcome in dyslipidemic ischemic stroke patients treated in the telestroke network. For the ischemic stroke population without dyslipidemia, increasing age (OR ​= ​1.070, 95% CI, 1.031-1.109, P ​< ​0.001), coronary artery disease (OR ​= ​3.633, 95% CI, 1.307-10.099, P ​= ​0.013), history of drug or alcohol abuse (OR ​= ​6.548, 95% CI, 1.106-38.777, P ​= ​0.038), and improvement in ambulatory outcome (OR ​= ​2.880, 95% CI, 1.183-7.010, P ​= ​0.020) were associated with worsening neurological functions, while being Caucasian (OR ​= ​0.294, 95% CI, 0.098-0.882, P ​= ​0.029) was associated with improving neurologic functions.

CONCLUSION

Demographic and clinical risk factors among the dysplipidemic ischemic stroke population in the telestroke network were not associated with worsening neurologic functions.

The risk of ischemic stroke and hemorrhagic stroke in Chinese adults with low-density lipoprotein cholesterol concentrations < 70 mg/dL

BACKGROUND

The risk of stroke in individuals with very low low-density lipoprotein cholesterol (LDL-C) concentrations remains high. We sought to prioritize predictive risk factors for stroke in Chinese participants with LDL-C concentrations < 70 mg/dL using a survival conditional inference tree, a machine learning method.

METHODS

The training dataset included 9327 individuals with LDL-C concentrations < 70 mg/dL who were free of cardiovascular diseases and did not use lipid-modifying drugs from the Kailuan I study (N = 101,510). We examined the validity of this algorithm in a second Chinese cohort of 1753 participants with LDL-C concentrations < 70 mg/dL from the Kailuan II study (N = 35,856).

RESULTS

During a mean 8.5-9.0-year follow-up period, we identified 388 ischemic stroke cases and 145 hemorrhagic stroke cases in the training dataset and 20 ischemic stroke cases and 8 hemorrhagic stroke cases in the validation dataset. Of 15 examined predictors, poorly controlled blood pressure and very low LDL-C concentrations (≤ 40 mg/dL) were the top hierarchical predictors of both ischemic stroke risk and hemorrhagic stroke risk. The groups, characterized by the presence of 2-3 of aforementioned risk factors, were associated with a higher risk of ischemic stroke (hazard ratio (HR) 7.03; 95% confidence interval (CI) 5.01-9.85 in the training dataset; HR 4.68, 95%CI 1.58-13.9 in the validation dataset) and hemorrhagic stroke (HR 3.94, 95%CI 2.54-6.11 in the training dataset; HR 4.73, 95%CI 0.81-27.6 in the validation dataset), relative to the lowest risk groups (presence of 0-1 of these factors). There was a linear association between cumulative average LDL-C concentrations and stroke risk. LDL-C concentrations ≤ 40 mg/dL was significantly associated with increased risk of ischemic stroke (HR 2.07, 95%CI 1.53, 2.80) and hemorrhagic stroke (HR 2.70, 95%CI 1.70, 4.30) compared to LDL-C concentrations of 55-70 mg/dL, after adjustment for age, hypertension status, and other covariates.

CONCLUSION

Individuals with extremely low LDL-C concentrations without previous lipid-modifying treatment could still be at high stroke risk.

TRIAL REGISTRATION

Chinese Clinical Trial Register, ChiCTR-TNRC-11001489 . Registered on 24-08-2011.

Obstructive sleep apnea and stroke severity: Impact of clinical risk factors

BACKGROUND

Specific clinical and demographic risk factors may be associated with improving or worsening neurologic outcomes within a population of acute ischemic stroke (AIS) patients with a history of obstructive sleep apnea (OSA). The objective of this study was to determine the changes in neurologic outcome during a 14-day recovery as it relates to initial stroke severity in AIS patients with OSA.

METHODS

This retrospective study analyzed baseline clinical risk factors and demographic data collected in a regional stroke center from January 2010 to June 2016. Our primary endpoint measure was the National Institutes of Health Stroke Scale (NIHSS) score and our secondary endpoint measures included the clinical factors associated with improving (NIHSS score ≤7) or worsening (NIHSS score >7) neurological outcome. The relative contribution of each variable to stroke severity and related outcome was determined using a logistic regression. The regression models were checked for the overall correct classification percentage using a Hosmer-Lemeshow test, and the sensitivity of our models was determined by the area under the receiver operating characteristic curve.

RESULTS

A total of 5469 AIS patients were identified. Of this, 96.89% did not present with OSA while 3.11% of AIS patients presented with OSA. Adjusted multivariate analysis demonstrated that in the AIS population with OSA, atrial fibrillation (AF) (odds ratio [OR] = 3.36, 95% confidence interval [CI], 1.289-8.762, P = 0.013) and changes in ambulatory status (OR = 2.813, 95% CI, 1.123-7.041, P = 0.027) showed an association with NIHSS score >7 while being Caucasian (OR = 0.214, 95% CI, 0.06-0.767, P = 0.018) was associated with NIHSS score ≤7.

CONCLUSION

In AIS patients with OSA, AF and changes in ambulatory status were associated with worsening neurological outcome while Caucasian patients were associated with improving neurological outcome. Our findings may have significant implications for patient stratification when determining treatment protocols with respect to neurologic outcomes in AIS patients with OSA.

Non-High-Density Lipoprotein Cholesterol Predicts Adverse Outcomes in Acute Ischemic Stroke

[Figure: see text].

A Meta-Analysis of Prognostic Factors in Patients with Posterior Circulation Stroke after Mechanical Thrombectomy

BACKGROUND

Posterior circulation stroke is characterized by poor prognosis because its optimal thrombolysis "time window" is always missed. After mechanical thrombectomy (MT), the recanalization rate of posterior circulation obstruction is significantly increased, but prognosis remains poor. To best manage patients, prognostic factors are needed to inform MT triaging after posterior circulation stroke.

METHODS

A systematic literature search was done for the period through April 2020. Studies included those with posterior circulation stroke cases that underwent MT. The primary outcome measure in this study was the modified Rankin Scale on day 90.

RESULTS

No outcome differences were found in gender, atrial fibrillation, smoking, and coronary artery disease (OR = 1.07, 95% CI: 0.90-1.28; OR = 1.02, 95% CI: 0.82-1.26; OR = 1.26, 95% CI: 0.94-1.68; and OR = 0.84, 95% CI: 0.58-1.22, respectively). Hypertension, diabetes mellitus, and previous stroke correlated with poorer prognosis (OR = 0.61, 95% CI: 0.48-0.77; OR = 0.60, 95% CI: 0.50-0.73; and OR = 0.74, 95% CI: 0.55-0.99, respectively). However, hyperlipidemia correlated with better prognosis (OR = 1.28, 95% CI: 1.04-1.58).

CONCLUSION

Our analysis indicates that hypertension, diabetes mellitus, or previous stroke correlate with poorer outcomes. Intriguingly, hyperlipidemia correlates with better prognosis. These factors may help inform triage decisions when considering MT for posterior circulation stroke patients. However, large, multicenter, randomized controlled trials are needed to validate these observations.

Association Between Non-high-density Lipoprotein Cholesterol and 3-Month Prognosis in Patients With Spontaneous Intracerebral Hemorrhage

Background: Previous studies have indicated a significant correlation between cholesterol levels and the incidence and outcomes of intracerebral hemorrhage (ICH), However, the association between non-high-density lipoprotein cholesterol (non-HDLC) levels and ICH functional outcomes are still unclear.

Method: We included 654 consecutive spontaneous ICH patients who were enrolled in a prospective registry. We collected clinical, demographic, and laboratory data using standardized forms, and non-HDLC levels and 3-month modified Rankin Scale (mRS) scores were recorded. We performed multivariate logistic regression and interaction analyses to explored the association between non-HDLC levels and ICH functional outcomes.

Results: Of 654 patients included in the study, 281 (42.9%) had poor functional outcome. Univariate analysis showed that high non-HDLC level was associated with good functional outcome at 90 days (p = 0.001). After adjustment for confounding factors, a high non-HDLC level (≥154.89 mg/dl) remained as an indicator of good functional outcome at 90 days [multivariate-adjusted odds ratios (OR) 0.50, 95%CI 0.27–0.92; p-value for trend = 0.043], and was stronger for female patients (OR: 0.13, 95%CI: 0.03–0.50).

Conclusion: ICH patients with higher non-HDLC levels had a decreased prevalence of poor functional outcome at 90 days, and a high non-HDLC level is an independent indicator of good functional outcome at 90 days from onset, especially in females.