Low-density-lipoprotein particle size predicts a poor outcome in patients with atherothrombotic stroke

Glycated serum protein is independently associated with progressive infarction in patients with acute ischemic stroke

OBJECTIVE

This study investigated the relationship between glycated serum protein (GSP) and progressive infarction (PI).

METHODS

From April 2017 to December 2020, we recruited 477 patients within 48 hours after the onset of acute ischemic stroke into this case-control study. Demographic characteristics, clinical information, and laboratory and neuroimaging data were recorded after admission.

RESULTS

PI occurred in 144 (30.8%) patients. Patients with PI had higher initial National Institute of Health Stroke Scale (NIHSS) scores, higher discharge NIHSS scores, higher modified Rankin scale scores at 3 months after onset, higher GSP levels, lower prothrombin times, and lower creatinine levels than patients without PI. The likelihood of PI increased with increases in the GSP quartile. Multiple regression analysis revealed that high GSP levels (>2.14 mmol/L) were independently associated with PI. Subgroup analyses identified high GSP levels as an independent predictor of PI in patients with large artery atherosclerosis (third quartile: odds ratio [OR] = 3.793; 95% confidence interval [CI] = 1.555-9.250; fourth quartile: OR = 2.675; 95% CI = 1.056-6.776) and anterior circulation small vessel occlusion (fourth quartile: OR = 13.859; 95% CI = 2.024-94.885).

CONCLUSIONS

GSP might be an independent predictor for PI in certain patients with acute ischemic stroke.

Misuse of multinomial logistic regression in stroke related health research: A systematic review of methodology

Multinomial logistic regression (MLR) is often used to model the association between a nominal outcome variable and one or more covariates. The results of MLR are interpreted as relative risk ratios (RRR) and warrant a more coherent interpretation than ordinary logistic regression. Some authors compare the results of MLR to ordinal logistic regression (OLR), irrespective of the fact that these estimate different quantities. We aim to investigate the time trends in the use and misuse of MLR in studies including stroke patients, specifically the extent to which (1) the results are denoted as anything other than RRR, (2) comparisons are made of results with results of OLR and (3) results have been interpreted coherently. Secondarily, we examine the use of model validation techniques in studies with predictive aims. We searched EMBASE and PubMed for articles using MLR on populations of stroke patients. Identified studies were screened, and information pertaining to our aims was extracted. A total of 285 articles were identified through a systematic literature search, and 68 of these were included in the review. Of these, 60 articles (88%) did not denote exponentiated coefficients of MLR as relative risk ratios but rather some other measure. Additionally, 63 articles (93%) interpreted the results of MLR in a non-coherent manner. Two articles attempted to compare MLR results with those of OLR. Nine studies attempted to use MLR for predictive means, and three used relevant validation techniques. From these findings, it is clear that the interpretation of MLR is often suboptimal.

The Atherogenic Index of Plasma is Independently Associated with Symptomatic Carotid Artery Stenosis

INTRODUCTION

Small, dense low-density lipoprotein (sdLDL) is strongly associated with symptomatic carotid artery stenosis, but is not routinely evaluated in ischemic stroke patients. A method using the logarithmic transformation of the ratio of the plasma concentration of triglycerides (TGY) to HDL-cholesterol (HDL-C)[(Log[TGY/HDL-C])] has been described as a surrogate marker for sdLDL termed the atherogenic index of plasma (AIP).

OBJECTIVE

To determine if the AIP is independently associated with symptomatic carotid artery stenosis.

METHODS

We conducted a single center case-controlled study using a sample of ischemic stroke patients and compared risk factors of patients with and without symptomatic carotid artery stenosis. A multivariate logistic regression model was used to determine if the AIP divided into four quartiles was independently associated with symptomatic carotid artery stenosis. This model was compared to three other lipid models. Associations between non-lipid variables and the AIP were also identified.

RESULTS

31 cases of ischemic stroke due to symptomatic carotid artery stenosis and 236 controls of ischemic stroke not due to carotid artery stenosis were identified. Of the four lipid models assessed, only the model including the AIP (model 4) was found to be significantly associated with symptomatic carotid artery stenosis. The odd's ratio (OR) for quartile 3 was 3.82 (95% CI 1.03-14.17) and the OR for quartile 4 was 4.13 (95% CI 1.09-15.54) using quartile 1 as a reference. Metabolic syndrome was the only variable associated with the AIP (OR 5.06 95% CI 2.6-9.7).

CONCLUSION

At our single center, the AIP was the only lipid parameter independently associated with symptomatic carotid artery stenosis; and metabolic syndrome was independently associated with the AIP. The AIP may serve as a useful surrogate of sdLDL in patients with symptomatic carotid artery stenosis.

Changes in High-Density Lipoproteins Related to Outcomes in Patients with Acute Stroke

Modifications in high-density lipoprotein (HDL) particle sizes and HDL-binding proteins have been reported in stroke patients. We evaluated whether the lipoprotein profile, HDL composition and functionality were altered in stroke patients according to their clinical outcome using the modified Rankin Score at 3 months. Plasma samples were obtained from stroke patients treated with intravenous thrombolysis. Levels of cardiovascular and inflammatory markers in plasma were measured using the Human CVD Panel 1 (Milliplex^® MAP). Lipoprotein subfractions from plasma were quantified by non-denaturing acrylamide gel electrophoresis, using the Lipoprint^®-System (Quantimetrix^®), and HDLs were isolated by ultracentrifugation. Relative amounts of paraoxonase-1 (PON1) and alpha-1 anti-trypsin (AAT) in the isolated HDLs were determined by Western blot. HDL anti-inflammatory function was evaluated in human blood-brain barrier endothelial cells stimulated with 100 ng/mL TNFα, and HDL antioxidant function was evaluated via their capacity to limit copper-induced low-density lipoprotein oxidation. Stroke patients with unfavorable outcomes had a lower proportion of small-sized HDLs and increased plasma levels of E-selectin (SELE) and the intercellular adhesion molecule 1 (ICAM1). HDLs from patients with unfavorable outcomes had lower levels of PON1 and displayed a blunted capacity to reduce the expression of SELE, interleukin 8 (IL8) and the monocyte chemoattractant protein-1 (MCP1) mRNA induced by TNFα in endothelial cells. These HDLs also had a reduced antioxidant capacity relative to HDLs from healthy donors. In conclusion, an increased ratio of large/small HDLs with impaired anti-inflammatory and antioxidant capacities was associated with unfavorable outcomes in stroke patients. Alteration of HDL functionality was mainly associated with a low amount of PON1 and high amount of AAT.

Sympathetic Overactivity Based on Heart-Rate Variability in Patients with Obstructive Sleep Apnea and Cerebral Small-Vessel Disease

Background and Purpose

Obstructive sleep apnea (OSA) is associated with cerebral white-matter changes (WMC), but the underlying mechanisms are not completely understood. Our aim was to identify the cardiovascular autonomic characteristics during sleep that are associated with cerebral WMC in OSA patients.

Methods

We recruited subjects from our sleep-center database who underwent both polysomnography and brain MRI within a 1-year period. Sixty patients who had OSA with WMC (OSA+WMC), 44 patients who had OSA without WMC (OSA−WMC), and 31 control subjects who had neither OSA nor WMC were analyzed. Linear and nonlinear indices of heart-rate variability (HRV) were analyzed in each group according to different sleep stages and also over the entire sleeping period.

Results

Among the nonlinear HRV indices, the Poincaré ratio (SD12) during the entire sleep period was significantly increased in the OSA+WMC group, even after age adjustment. Meanwhile, detrended fluctuation analysis 1 during non-rapid-eye-movement sleep tended to be lowest in the OSA+WMC group. These indices were altered regardless of the presence of hypertension or diabetes. In the subgroup analysis of middle-aged OSA patients, approximate entropy during rapid-eye-movement sleep was significantly lower in OSA+WMC patients than in OSA−WMC patients. Overall, the nonlinear HRV indices suggest that sympathetic activity was higher in the OSA+WMC group than in the OSA−WMC and control groups.

Conclusions

Our findings suggest that dysregulation of HRV, especially overactivation of sympathetic tone, could be a pathophysiologic mechanism underlying the development of WMC in OSA patients.

Moderate-to-severe obstructive sleep apnea is associated with cerebral small vessel disease

BACKGROUND

Cerebral small vessel disease (SVD) is associated with increased risk of cerebral infarction and hemorrhage. Obstructive sleep apnea (OSA) is known to increase the risk of cerebrovascular disease. This study aimed to investigate the association between cerebral SVD and severity of OSA.

METHODS

A total of 170 patients were included from the patient registry at the present Sleep Center; these patients underwent both magnetic resonance imaging (MRI) of the brain and polysomnography (PSG) for suspected OSA. The presence and burden of white matter hyperintensities (WMHs), asymptomatic lacunar infarctions (ALIs), cerebral microbleeds (CMBs), and perivascular spaces (PVSs) were determined by MRI, and their relationships with the apnea-hypopnea index (AHI), as determined by PSG, were investigated.

RESULTS

Among the 170 patients, 25 (14.7%) had high-grade WMHs, 21 (12.4%) had ALIs, 21 (12.4%) had CMBs, and 34 (20.0%) had high-grade PVSs. In the multivariable analysis, after adjusting for factors including age, sex, and other variables for which p <0.1 in univariable analysis (hypertension, diabetes mellitus, previous stroke, minimal SaO₂ and arousal index), moderate-to-severe OSA was associated with high-grade WMHs (odds ratio [OR] 4.72; 95% confidence interval [CI] 1.14-19.47), CMBs (OR 3.47; 95% CI 0.89-15.18), or high-grade PVSs (OR 3.64; 95% CI 1.02-13.01), but not with ALIs. The total SVD score was independently associated with increased AHI (p = 0.017), particularly in patients with moderate-to-severe OSA (β [standard error] = 0.448 (0.204), p = 0.030].

CONCLUSION

Moderate-to-severe OSA is positively associated with multiple indicators of cerebral SVD, including WMHs, CMBs, and PVSs.