Prognostic Role of Mean Platelet Volume and Platelet Count in Ischemic and Hemorrhagic Stroke

Potential Predictive Value of Platelet Distribution Width for Functional Outcome After Ischemic Stroke

Complete blood cell count (CBC) is the most common and readily available laboratory test in clinical practice. The relationships of some CBC indices with ischemic stroke have been reported in observational studies; however, the causal direction is not specified. This study aimed to explore the causal relationships between CBC indices and the modified Rankin Scale (mRS) score at 3 months after ischemic stroke. Genetic associations of 22 blood cell traits were obtained from the UK Biobank database (n = 350,475). The outcome data for ischemic stroke were obtained from the Genetic Ischemic Stroke Functional Outcome (GISCOME) network (n = 6021). We implemented two-sample Mendelian randomization (TSMR) and several complementary analyses to assess the causal association between blood traits and unfavorable outcome (3-month mRS > 2). The clinical cohort was validated based on the results of the MR analysis. TSMR result indicated causal association between genetically determined platelet distribution width (PDW) and adverse functional outcome after ischemic stroke (OR 1.48; 95% CI 1.13-1.95; p = 0.005). Complementary analyses showed negligible causal effect of genetic variants on stroke subtypes. In cohort study (n = 351), higher level of PDW was observed in the unfavorable outcome group. However, the multivariable logistic regression analysis failed to identify the improvement in predictive performance of stroke outcomes by adding PDW to the prediction model. Further correlation analysis revealed that PDW is positively correlated with serum glucose levels, and the level of PDW in the non-thrombolysed group was significantly higher than that in the thrombolysis group, indicating that PDW may be involved in stroke prognosis in an indirect way.

Hematological predictors of silent new cerebral ischemic lesions in carotid artery stenting: A retrospective study

BACKGROUND

Silent new cerebral ischemic lesions (sNCIL) are a common complication of carotid artery stenting (CAS) that can lead to an increase in morbidity and mortality. We aimed to evaluate the impact of hematological parameters on sNCIL in patients undergoing CAS.

METHODS

We retrospectively evaluated 103 patients who underwent CAS, with a mean age of 70.5 ± 6.7 years, and 31 (20.1 %) of whom were female. Stents were placed for internal carotid artery revascularization. The presence of new hyperintense lesions on diffusion-weighted imaging (DWI) without neurological symptoms was considered as sNCIL in cases without apparent neurological findings. Patients were categorized into two groups based on DWI results: positive (29) and negative (74).

RESULTS

In the study population, sNCIL was observed in 29 patients (28.2 %). The DWI-positive group exhibited significantly higher Plateletcrit (PCT) levels, advanced age, and a lack of embolic protection device usage compared to the DWI-negative group. The Receiver Operating Characteristic (ROC) analysis identified a PCT value of 0.26 as the optimal threshold, detecting the development of sNCIL with a sensitivity of 75.9 % and specificity of 59.1 % (AUC: 0.700; 95 % CI: 0.594-0.806, p = 0.002).

CONCLUSION

To be determined by a simple blood parameter, PCT can predict the risk of sNCIL before CAS and holds clinical value in the treatment of patients with carotid artery stenosis.

Effect of mean platelet volume and platelet count on the prognosis of branch atheromatous disease

OBJECTIVE

The purpose of this study was to investigate the predictive value of mean platelet volume (MPV) and platelet count (PC) in branch atheromatous disease (BAD).

METHODS

This retrospective study included 216 patients with BAD-stroke within 48 h of symptom onset. These patients were divided into good and poor prognosis groups according to their 3-month modified Rankin scale scores after discharge. Multiple logistic regression analysis was used to evaluate independent predictors of poor prognosis in BAD-stroke patients. Receiver-operating characteristic (ROC) analysis was used to estimate the predictive value of MPV and PC on BAD-stroke.

RESULTS

Our research showed that a higher MPV (aOR, 2.926; 95% CI, 2.040-4.196; p < .001) and PC (aOR, 1.013; 95% CI, 1.005-1.020; p = .001) were independently associated with poor prognosis after adjustment for confounders. The ROC analysis of MPV for predicting poor prognosis showed that the sensitivity and specificity were 74% and 84.9%, respectively, and that the AUC was .843 (95% CI, .776-.909, p < .001). The optimal cut-off value was 12.35. The incidence of early neurological deterioration (END) was 24.5% (53 of 163), and 66% of patients in the poor prognosis group had END (33 of 50). Multiple logistic regression analyses showed that elevated MPV and PC were associated with the occurrence of END (p < .05).

CONCLUSION

Our results suggested that an elevated MPV and PC may be important in predicting a worse outcome in BAD-stroke patients. Our study also demonstrated an independent association of MPV and PC with END, which is presumably the main reason for the poor prognosis.

A Study to Estimate the Red Cell Width Distribution and the Mean Platelet Volume in Predicting the 30-Day Mortality in Acute Ischemic Stroke Patients

Background Acute ischemic stroke, a clinical disorder caused by nontraumatic cerebrovascular disease, has an acute onset, frequently causes neurological deficit, and may persist for >24 hours or can be fatal in <24 hours. This study aimed to assess the red cell width distribution (RDW) and the mean platelet volume (MPV) in predicting 30-day mortality in acute ischemic stroke patients. In general, patients with acute ischemic stroke have a rather high mortality rate in the first 30 days due to various complications, but post the 30-day mark, the prognosis is comparatively better. Material and methods The present study was conducted on patients with a confirmed diagnosis of acute ischemic stroke based on history, physical examination, CT scan, and/or diffusion-weighted MRI scan performed during the first 24 hours. It was a prospective and cross-sectional study done at Saveetha Medical College over a period of two years. The data was collected by using the intra-hospital network and was analyzed using the IBM SPSS Statistics for Windows, Version 20 (Released 2011; IBM Corp., Armonk, New York, United States). Results In the present study, among 100 patients, the mean age was 57.4 ± 13.36 years. About 55% of our subjects were males in our study. The RDW on the 1stday was 14.17 ± 0.708, and it reduced drastically on the 30thday to1st 13.55 ± 1.11, and it was statically significant (p = 0.000). The MPV on day 1 was 11.11 ± 0.969 and, on day 30, was 10.82 ± 0.90; the MPV was reduced considerably on day 30, which was statistically significant (p = 0.000). RDW on the 1st day was significantly correlated with the MPV and the volume of stroke. The correlation was significant at the 0.01 level (two-tailed). On the 30th day of acute ischemic stroke patients, the red blood cell (RBC) width was significantly correlated with the MPV. The correlation was significant at the 0.01 level (two-tailed). At the end of 30 days, 10% mortality was observed in the present study. Day 30 saw a significant decrease in the MPV and RDW, particularly in the moderate to severe and severe categories. The National Institutes of Health Stroke Scale (NIHSS) score and the volume of stroke were significantly associated with the 30-day outcome.  Conclusion The RDW and the MPV are well correlated in predicting the 30-day mortality in acute ischemic stroke patients. This could potentially be used as a significant marker for predicting mortality in stroke patients in the future, but to increase the generalization, further studies need to be carried out at other demographically distinct medical centers.

Elevated platelet count is associated with decreased mortality from hemorrhagic stroke in hospital: a multi-center retrospective cohort study

This study aimed to investigate the relationship between platelet count (PC) and mortality in patients with hemorrhagic stroke (HS). The research reviewed data from 10,466 patients hospitalized in 208 hospitals in the United States from January 1, 2014, to December 31, 2015. Of these, 3262 HS patients were included in the primary analysis for those admitted to the intensive care unit (ICU). The average age of these patients was 67.05 years, with 52.79% being male. The median PC was (221.67 ± 73.78) × 109/L. Multivariate logistic regression analysis revealed that PC was a protective factor for mortality in HS patients (OR = 0.98, 95% CI 0.97-1.00, P < 0.05). Additionally, a non-linear association between PC and mortality in HS patients was found using a generalized additive model (GAM) and smooth curve fitting (penalty spline method). For the first time, a recursive algorithm identified the inflection point of platelet count as 194 × 109/L. On the left side of the inflection point, for every increase of 10 units in platelet count, the mortality rate of HS patients decreases by 10%. The study demonstrates a non-linear relationship between PC and the risk of mortality in HS patients. A platelet counts higher than the inflection point (194 × 109/L) may be a significant intervention to reduce mortality in HS patients.

The day after intracerebral hemorrhage: platelet mass index as predictor of survival—a retrospective cohort study

Background

Platelets are implicated in the pathophysiology of intracerebral hemorrhage (ICH). Platelet count (PLT) is affected by platelet loss, while mean platelet volume (MPV) by platelet replenishment. Whether platelet mass index (PMI), the product of PLT and MPV, might predict survival after ICH, remains unknown.

Methods

All first-ever ICH patients, admitted to Xanthi General Hospital between January 2018 and May 2020 and met eligibility criteria, were enrolled in this retrospective cohort study. Demographics, medical record, first-symptom-to-admission time, vital signs, modified Rankin Scale, ICH score, arterial blood gas test, complete blood count, blood biochemistry, and CT scan test were collected for each patient. PMI values on day 1 (admission; PMI1), day 2 (PMI2), and day 7 (PMI7), along with PLT, MPV, platelet distribution width (PDW), and platelet large cell ratio (P-LCR), were evaluated as potential predictors of 12-month survival using Repeated Measures General Linear Model. Binary discretization of predictors was based on optimal scaling and evaluated using binary regression.

Results

From 59 patients enrolled (aged 75.7 ± 12.0 years; 31 females), 29 were still alive 12 months after ICH. Age, arterial hypertension, diabetes mellitus, hemoglobin level (Hb), and oxygen saturation (O2Sat) were correlated with 12-month survival. After adjustment for these parameters, PMI1 and PMI2 were independently correlated with 12-month survival (P = 0.048 and P = 0.004, respectively), while PMI7 was not (P = 0.332). PMI2 ≥ 2,400 fL/μL was best to discriminate survivors from non-survivors (age, arterial hypertension, diabetes mellitus, Hb, and O2Sat adjusted OR 0.123 with 95% CI: 0.023–0.694; P = 0.018).

Conclusions

PMI within the first day after admission for ICH might be used as early predictors of survival. Properly designed prospective studies are needed to further evaluate their contribution as such.

Safety and efficacy of direct oral anticoagulants in stroke prevention in patients with atrial fibrillation complicated with anemia and/or thrombocytopenia: a retrospective cohort study

BACKGROUND

There are limited data about the clinical benefits and harm of direct oral anticoagulants (DOACs) in stroke prevention in patients with atrial fibrillation (AF) complicated with anemia or thrombocytopenia.

METHODS

This is a multi-center retrospective cohort study involving 5469 AF patients from 15 hospitals in China. Patients were divided into three groups according to hemoglobin and platelet levels: Group 1 (hemoglobin male ≥ 130 g/L; female ≥ 120 g/L and platelet ≥ 100 × 109/L), Group 2 (hemoglobin male < 130 g/L; female < 120 g/L or platelet < 100 × 109/L), and Group 3 (hemoglobin male < 130 g/L; female < 120 g/L and platelet < 100 × 109/L). Patients in each category are further divided into two groups according to their stroke prevention strategies: rivaroxaban or dabigatran. Clinical results include major, minor, total bleeding, thrombosis, and the composite outcome of major bleeding and thrombosis.

RESULTS

Higher hemoglobin levels were associated with a reduced risk of total bleeding and major bleeding, while platelet counts were not associated with any event. Compared with Group 1, Group 2 had a higher risk of major bleeding (aOR 1.70, 95%CI 1.12-2.57, P = 0.012), and the composite endpoint of major bleeding and thrombosis (aOR 1.70, 95%CI 1.19-2.44, P = 0.004). Compared with Group 1, Group 3 had a higher total bleeding risk (aOR 2.15, 95%CI 1.14-4.05, P = 0.018). Compared with dabigatran, rivaroxaban was associated with higher composite risk in Group 1 (aOR 2.91, 95% CI 1.66-5.16, P < 0.001) and Group 2 (aOR 3.05, 95%CI 1.46-6.39, P = 0.003), but there was no significant difference in Group 3 (aOR 1.78, 95%CI 0.23-13.54, P = 0.577).

CONCLUSIONS

Higher hemoglobin levels are associated with a reduced risk of total bleeding and major bleeding in patients with AF. Dabigatran was associated with better clinical outcomes than rivaroxaban in patients with anemia or thrombocytopenia but not in those with anemia and thrombocytopenia.

Genomic Variation Affecting MPV and PLT Count in Association with Development of Ischemic Stroke and Its Subtypes

Platelets play a significant role in the pathophysiology of ischemic stroke since they are involved in the formation of intravascular thrombus after erosion or rupture of the atherosclerotic plaques. Platelet (PLT) count and mean platelet volume (MPV) are the two significant parameters that affect the functions of platelets. In the current study, MPV and PLT count was evaluated using flow cytometry and a cell counter. SonoClot analysis was carried out to evaluate activated clot timing (ACT), clot rate (CR), and platelet function (PF). Genotyping was carried out using GSA and Sanger sequencing, and expression analysis was performed using RT-PCR. In silico analysis was carried out using the GROMACS tool and UNAFold. The interaction of significant proteins with other proteins was predicted using the STRING database. Ninety-six genes were analyzed, and a significant association of THPO (rs6141) and ARHGEF3 (rs1354034) was observed with the disease and its subtypes. Altered genotypes were associated significantly with increased MPV, decreased PLT count, and CR. Expression analysis revealed a higher expression in patients bearing the variant genotypes of both genes. In silico analysis revealed that mutation in the THPO gene leads to the reduced compactness of protein structure. mRNA encoded by mutated ARHGEF3 gene increases the half-life of mRNA. The two significant proteins interact with many other proteins, especially the ones involved in platelet activation, aggregation, erythropoiesis, megakaryocyte maturation, and cytoskeleton rearrangements, suggesting that they could be important players in the determination of MPV values. In conclusion, the current study demonstrated the role of higher MPV affected by genetic variation in the development of IS and its subtypes. The results of the current study also indicate that higher MPV can be used as a biomarker for the disease and altered genotypes, and higher MPV can be targeted for better therapeutic outcomes.

Platelet parameters and the association with morbidity and mortality in Preterm Infants

BACKGROUND

There is growing recognition of the role of platelets in inflammation and immune responses, and platelets have been associated with various cardiovascular diseases. It is also known that neonatal morbidities are related to overall platelet activity, and platelet parameters may have the potential to predict morbidities and mortality in preterm infants. This study aimed to assess the initial platelet parameters and the association with major morbidities and mortality in preterm neonates.

METHODS

We retrospectively reviewed data from very preterm neonates with a gestational age (GA) <32 weeks who were admitted between June 2020 and May 2021 for platelet parameters (counts, mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (platelet counts x MPV/10000(%)) at birth. Major morbidities included early- onset sepsis (EOS) ≤3 days after birth, severe intraventricular hemorrhage (IVH) grade ≥3, and early or overall mortality.

RESULTS

A total of 197 very preterm neonates were studied. Their mean (±SD) GA was 28.0 ± 2.4 weeks, birth weight was 990 ± 293 g, platelet counts were 245 ± 81 x1000/μL, MPV was 10.0 ± 0.7 fl, PDW was 11.0 ± 1.6 fl, and plateletcrit was 0.24 ± 0.08%. MPV had a weak negative correlation with both GA (r = -0.234, p = 0.001) and BW (r = -0.343, p <0.001). A lower plateletcrit was associated with EOS (0.14 (0.04-0.22) % vs. 0.23 (0.19-0.30) %, p = 0.027), severe IVH ≤7 days after birth (0.18 (0.14-0.27) % vs. 0.23 (0.20-0.30) %, p = 0.022), and early and overall mortality (0.15 (0.20-0.30) % vs. 0.23 (0.20-0.30) %, p = 0.049; 0.20 ± 0.09 % vs. 0.25 ± 0.07 %, p = 0.008).

CONCLUSION

A lower plateletcrit within 24 hours of birth was associated with EOS, severe IVH ≤7 days after birth, and first-week and overall mortality in very preterm neonates.

Reference interval of platelet counts and other platelet indices in apparently healthy blood donors in North India according to Clinical and Laboratory Standards Institute guidelines: Need to redefine the platelet count cutoffs for repeat plateletpheresis donation?

BACKGROUND

In clinical practice, laboratory results are of great importance for the diagnosis and treatment. Reference intervals of different parameters aid health-care professionals in the interpretation of results. There are very few studies on reference intervals from India. This prospective study was conducted to determine the reference intervals for platelet count (PLT) and PLT indices; mean PLT volume (MPV), PLT distribution width (PDW), and PLT large cell ratio (P-LCR). These values can be obtained as a part of a routine complete blood count (CBC) and have diagnostic and prognostic significance in certain diseases. PLT count is an important criterion for the selection of donors for repeat plateletpheresis donation.

MATERIALS AND METHODS

Sixteen hundred and thirty-four first-time healthy volunteer plateletpheresis donors were enrolled for the study. CBC was done, values of PLT, MPV, PDW, and P-LCR were noted, and the results were analyzed. The 95% of the reference distribution was estimated using the 2.5th and 97.5th percentiles following Clinical and Laboratory Standards Institute guidelines. Adverse donor reactions, if any and quality parameters of single donor PLTs (SDP) were also studied.

RESULTS

Reference range values of PLT, MPV, PDW, and P-LCR were 137,825-355,175/μl, 8.1-13.9/fl, 9.1-22.5/fl, and 11.7%-52.9%, respectively, and compared well with other published studies from India. It was observed that reference values of PLT count obtained in the study were lower than reference values that are currently used in most laboratories (150,000-450,000/μl) in India.

CONCLUSION

Based on our results, we are of the opinion that the PLT count cutoffs for repeat plateletpheresis donation may need to be revised downwards for our country which would also mitigate the scarcity of apheresis donors.

Characteristics and Outcomes of Intracranial Hemorrhage in Cancer Patients Visiting the Emergency Department

Intracranial hemorrhage (ICH) is a dreaded complication of both cancer and its treatment. To evaluate the characteristics and clinical outcomes of cancer patients with ICH, we identified all patients with ICH who visited The University of Texas MD Anderson Cancer Center emergency department between 1 September 2006 and 16 February 2016. Clinical and radiologic data were collected and compared. Logistic regression analyses were used to determine the association between clinical variables and various outcomes. During the period studied, 704 confirmed acute ICH cases were identified. In-hospital, 7-day, and 30-day mortality rates were 15.1, 11.4, and 25.6%, respectively. Hypertension was most predictive of intensive care unit admission (OR = 1.52, 95% CI = 1.09–2.12, p = 0.013). Low platelet count was associated with both in-hospital mortality (OR = 0.96, 95% CI = 0.94–0.99, p = 0.008) and 30-day mortality (OR = 0.98, 95% CI = 0.96–1.00, p = 0.016). Radiologic findings, especially herniation and hydrocephalus, were strong predictors of short-term mortality. Among known risk factors of ICH, those most helpful in predicting cancer patient outcomes were hypertension, low platelet count, and the presence of hydrocephalus or herniation. Understanding how the clinical presentation, risk factors, and imaging findings correlate with patient morbidity and mortality is helpful in guiding the diagnostic evaluation and aggressiveness of care for ICH in cancer patients.

Emergency department point‑of‑care biomarkers and day 90 functional outcome in spontaneous intracerebral hemorrhage: A single‑center pilot study

Spontaneous intracerebral hemorrhage (sICH) results in high morbidity and mortality rates, thus identifying strategies for timely prognosis and treatment is important. The present study aimed to analyze the relationship between emergency department point-of-care (POC) blood biomarkers and day 90 functional outcome (FO) in patients with acute (<8 h) sICH. On-site POC determinations, including complete blood count, glucose, cardiac troponin I, D-dimer and C-reactive protein, and derived inflammatory indexes were performed for a cohort of 35 patients. The primary endpoint was a favorable day 90 FO (modified Rankin Score ≤3). Secondary endpoints included early neurological worsening (ENW), day 7/discharge neurological impairment, day 90 independence assessment (Barthel Index <60), hematoma enlargement and perihematomal edema (PHE) growth. A favorable three-month FO was reported in 16 (46%) participants. Older age, previous history of ischemic stroke and initial imagistic parameters, including intraventricular hemorrhage, enlarged contralateral ventricle and cerebral atrophy, significantly predicted an unfavorable FO. The admission D-dimer similarly predicted day 90 FO and the independence status, along with ENW and a more severe day 7/discharge neurological status. The D-dimer also correlated with the initial neurological status and PHE. PHE growth correlated with granulocytes, systemic immune-inflammation index and glycemia. The results suggested that a lower admission D-dimer could indicate an improved day 90 FO of patients with sICH, while also anticipating the development of PHE growth and ENW.

Evaluation of platelets activity and reactivity as risk factors for acute ischemic non-embolic stroke in young adults

Background

Ischemic stroke (IS) constitutes a relevant health concern recently in younger population causing permanent cognitive and function-limiting disability and ranks as the 3rd cause of death in Egypt after cardiac and hepatic diseases. Platelet activation has a crucial mechanism in arterial thrombogenesis, thus in pathophysiology of IS. Surface expression of P-selectin (CD62P) reflects platelet activation and measured by flowcytometry. The purpose of the study is to evaluate whether platelet activity and reactivity are considered risk factors for IS so more restrict antiplatelet protocols could be implemented for management and recurrence prevention.

Results

Study population was 60 IS patients and 60 apparently healthy age and gender-matched controls. Patients were subdivided into 37 patients without classical risk factors, aged 46.1 ± 8.2, and 23 patients with > 1 vascular risk factors, aged 52 ± 9.9. The percentage of platelets expressing CD62P reflecting ex vivo baseline activity was significantly higher in stroke patients to controls (p = 0.001), also platelet reactivity (CD62P expression after ADP provocation) was statistically significantly elevated in patients than in controls (p < 0.0001) and was significantly higher in IS patients with vascular risk factors compared to patients without risk factors (p = 0.02).

Conclusion

Both baseline platelet activity and reactivity were significantly higher in IS patients, and were also higher in IS patients with other vascular risk factors than in cryptogenic stroke and considered risk factors for IS.

Evaluation of combining Alberta Stroke Program Early CT Score (ASPECTS) with mean platelet volume, plateletcrit, and platelet count in predicting short- and long-term prognosis of patients with acute ischemic stroke

BACKGROUND

There is controversy regarding Alberta Stroke Program Early CT Score (ASPECTS) and platelet indices as predictors of outcome in patients with acute ischemic stroke (AIS). We aimed to assess the prognostic value of ASPECTS, mean platelet volume (MPV), plateletcrit (PCT), and platelet count (Plt) in 3-month and 1-year functional outcomes of AIS patients, both independently and in combination.

METHODS

This prospective study was conducted in Shams Al-shomuos and Ghaem hospitals of Mashhad, Iran from June 2019 to January 2021. Overall, 553 patients above 18 years old with first-ever anterior circulation AIS met the eligibility criteria and were included. Clinical, hematologic, radiologic, and demographic data of patients were recorded at baseline. The 3-month and 1-year functional outcome was evaluated by modified Rankin Scale (mRS). Multivariate logistic regression was used to determine the independent predictors of poor functional outcome (mRS>2) and mortality.

RESULTS

The mean age of the patients was 65.50 ± 14.41 years and 282 patients (51%) were male. ASPECTS ≤ 7 was an independent predictor of both poor function (OR=1.94, 95%CI=1.04-3.62, P = 0.04) and mortality (OR=2.02, 95%CI=1.14-3.58, P = 0.02) at 1 year. MPV was also a strong predictor of 3-month (OR=3.88, 95%CI=2.04-7.38, P = 0.02) and 1-year (OR=3.32, 95%CI=1.91-5.78, P = 0.01) mortality, as well as 3-month (OR=3.25, 95%CI=1.80-5.86, P < 0.001) and 1-year (OR=4.35, 95%CI=2.36-8.02, P < 0.001) poor function. For 1-year poor function (OR=9.33, 95%CI=2.19-39.73, P = 0.003) and mortality (OR=6.40, 95%CI=2.09-19.64, P = 0.001), ASPECTS combined with all platelet indices found to be a more robust independent predictor compared to each variable alone.

CONCLUSION

Although MPV is an independent predictor of both 3-month and 1-year poor function and mortality in AIS patients, ASPECTS ≤ 7 was found to be a risk factor for 1-year poor function and mortality. Moreover, the prognostic value of both platelet indices and ASPECTS are greater when they are combined together in AIS patients.

Biomarkers for Antiplatelet Therapies in Acute Ischemic Stroke: A Clinical Review

Stroke is one of the world's leading causes of disability and death. Antiplatelet agents are administered to acute ischemic stroke patients as secondary prevention. Clopidogrel involves biotransformation by cytochrome P450 (CYP) enzymes into an active metabolite, and single nucleotide polymorphisms (SNPs) can influence the efficacy of this biotransformation. Despite the therapeutic advantages of aspirin, there is significant inter-individual heterogeneity in response to this antiplatelet drug. In this clinical review, the recent advances in the biomarkers of antiplatelet agents in acute ischemic stroke are discussed. The studies reviewed herein highlight the clinical relevance of antiplatelet resistance, pharmacotherapy of antiplatelet agents predicting drug response, strategies for identifying aspirin resistance, pharmacogenetic variants of antiplatelet agents, miRNAs, and extracellular vesicles (EVs) as biomarkers toward the personalized approach in the management of acute ischemic stroke. The precise pathways contributing to antiplatelet resistance are not very well known but are presumably multi-factorial. It is essential to understand the clinical relevance of clopidogrel and aspirin-related single nucleotide polymorphism (SNPs) as potential predictive and prognostic biomarkers. Prasugrel is a next-generation antiplatelet agent that prevents ADP-platelet activation by binding irreversibly to P2Y12 receptor. There are sporadic reports of prasugrel resistance and polymorphisms in the Platelet endothelial aggregation receptor-1 (PEAR1) that may contribute to a change in the pharmacodynamics response. Ticagrelor, a direct-acting P2Y12-receptor antagonist, is easily absorbed and partly metabolized to major AR-C124910XX metabolite (ARC). Ticagrelor's primary active metabolite, ARC124910XX (ARC), is formed via the most abundant hepatic cytochrome P450 (CYP) enzyme, CYP3A4, and CYP3A5. The integration of specific biomarkers, genotype as well as phenotype-related data in antiplatelet therapy stratification in patients with acute ischemic stroke will be of great clinical significance and could be used as a guiding tool for more effective, personalized therapy.

Red cell index: A novel biomarker for 3-month mortality in acute ischemic stroke patients treated with intravenous thrombolysis

BACKGROUND

The red cell index (RCI) was described as a biomarker for evaluating respiratory function in previous studies, but the relationship between RCI and stroke, remained a mystery. The present study aimed to probe the association between RCI at 24-hr and 3-month mortality and functional outcomes among acute ischemic stroke (AIS) patients treated with recombinant tissue plasminogen activator (r-tPA).

METHODS

A total of 217 AIS patients between January 2016 and January 2019 were recruited in this retrospective study. AIS patients were grouped in terms of RCI tertiles. Predictive factors were confirmed via multivariate logistic regression analysis. The receiver operating characteristic (ROC) was used to assess the ability of RCI in predicting mortality. In addition, the risk of 3-month all-cause mortality was evaluated by Cox proportional hazard model.

RESULTS

We grouped AIS patients into tertiles with the purpose of comparing clinical factors and RCI levels. Multivariate logistic regression analysis presented that RCI (odds ratio [OR] = 1.443, 95% confidence interval [CI] [1.167-1.786], p = 0.001) was an independent biomarker for 3-month all-cause mortality. The best cutoff value of RCI was 2.41 (area under the curve [AUC] = 0.639, 95% CI [0.501-0.778], p = .032), with a sensitivity of 40.9% and a specificity of 89.7%. Cox survival analysis demonstrated a positive significant correlation between RCI (hazard ratio [HR] = 1.332, 95% CI [1.148-1.545], p < .001) and mortality risk.

CONCLUSION

RCI, a potential predictor, was significantly associated with 3-month mortality in AIS patients with r-tPA.

Mean Platelet Volume is a Prognostic Marker in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis

BACKGROUND AND OBJECTIVES

There is conflicting data regarding the association between platelet parameters and prognosis of stroke patients treated with intravenous thrombolysis. We aimed to analyze this association in a cohort of patients treated with rtPA.

MATERIAL AND METHODS

Retrospective, observational study in adult ischemic stroke patients treated with rtPA between January 2015 and February 2017. Demographic and clinical characteristics, stroke severity (NIHSS), etiology (TOAST), mean platelet volume (MPV), platelet count (PC), platelet distribution width (PDW) and functional outcome (mRS) at discharge and 90 days were recorded. The association between platelet parameters and unfavorable prognosis (mRS 3-6) was tested using non-parametric tests and logistic regression analysis.

RESULTS

267 patients were included, 134 (50.2%) females, with a median (IQR) age of 74 years (64-82). The median admission NIHSS was 14 (8-19) and the most frequent etiology was cardioembolism (n = 115, 43.1%). At discharge, 170 (63.7%) patients had mRS 3-6. MPV values were higher in patients with mRS 3-6 (median 8.2fL versus 7.8fL, p = 0.013). This association remained significant (OR = 1.36, 95% CI 1.003-1.832, p = 0.048) after adjustment for variables associated with prognosis. There were no significant associations between other platelet parameters and prognosis. There was a trend to unfavorable prognosis at 90 days in patients with higher MPV. Regarding the association between platelet parameters and hemorrhagic transformation, higher PDW was associated with more severe hemorrhagic transformation (PH1/PH2).

CONCLUSIONS

Higher MPV values were associated with unfavorable prognosis at discharge in patients treated with intravenous thrombolysis. Future studies should address its added value in stroke prediction models.

Association of platelet count and mean platelet volume (MPV) index with types of stroke

Background:

Stroke is known to be the third most prominent cause of death in the developing countries and the most common debilitating neurologic disease. This study aimed to investigate the association of platelet count (PC) and mean platelet volume (MPV) index with various stroke types.

Methods:

This cross-sectional study was carried out on patients over the age of 18 years who presented with signs and symptoms of the first acute stroke. Exclusion criteria were underlying chronic liver or renal disease and the time more than 6 hours from symptom initiation, hematological and infectious disorders in patients. After recording of demographic data, a complete blood cell count (CBC) test was performed.

Results:

From 150 patients, who enrolled in the study, 54.7% of patients were males. The initial brain CT scan was normal in 13 (8.7%) patients and showed evidence of brain infarction and intracranial hemorrhage in 84 (56%) and 53 (35.3%) patients respectively. Patients with intracranial hemorrhage had significantly higher mean of MPV index than the patients with normal brain-CT scan and patients with evidence of brain infarction (p<0.001).

Conclusion:

The MVP index can be a predictor of the type of hemorrhagic or ischemic finding in emergency CT scan in stroke patients. This relationship may help to better understand the physiopathologic role of platelets in the development of stroke (hemorrhagic or ischemic), but will not replace cerebral computed tomography to diagnose the type of stroke, or it may not initiate treatment for hemorrhagic stroke.

Profile of reticulated platelets in the early, subacute and late phases after transient ischemic attack or ischemic stroke

Information regarding the profile of reticulated platelets (RP) in ischemic cerebrovascular disease (CVD) patients is limited. Data from two prospective, observational, case-control studies were combined to compare the %RP using whole blood flow cytometry in patients ≤ 4 weeks of TIA/stroke onset (baseline, N = 210), and 14 ±7 days (14d, N = 182) and ≥ 90 days (90d, N = 145) after starting or changing antiplatelet therapy with healthy controls (N = 34). There were no differences in median %RP between the overall CVD patient population at baseline or 14d vs. controls (P ≥ 0.2). However, the median %RP was significantly higher in CVD patients overall at 90d (P = .036), and in the subgroup of patients with "lacunar" TIA/ischemic stroke at baseline (P = .04) and at 90d (P = .01), but not at 14d (P = .06) vs. controls. There were no significant differences in the median %RP between other TIA/stroke subgroups and controls (P ≥ 0.05). Elevated circulating reticulated platelets, as a marker of increased platelet production/turnover, may occur following an ischemic event in a well-phenotyped TIA/ischemic stroke population overall, but may precede symptom onset at least in the subgroup with small vessel occlusion. These data improve our understanding of the profile of reticulated platelets in CVD patients.

Additional factors to corelate with a more than 30% NIHSS score improvement in patients 7 days after fibrinolytic and/or endovascular treatment for ischemic stroke

Background

Our objective was to find which additional factors can influence the favorable result in stroke patients after receiving fibrinolytic and/or endovascular treatment, quantified as a more than 30% improvement of the NIHSS score at 7 days.

Methods

This is a retrospective study to find factors that could influence a favorable evolution of patients with stroke that underwent fibrinolytic and or thrombectomy using the NIHSS score changes. At the admission in the hospital, blood glucose, blood count, coagulation time, INR, aPTT, PT, platelet count, NIHSS questionnaire and ASPECTS score were collected. NIHSS was assessed at the admission, after 1 h, after 2 h, after 24 h and after 7 days.

Results

As compared to the initial evaluation, at 7 days after admission 59% (72) of patients have improved with more than 30% the NIHSS. Higher levels of systolic blood pressure, glycemia and lower ASPECTS score at admission were observed in non-achievers. The value of INR contributed to model: for every unit increase of INR, the chance of better outcome decreases by 90,1%. High glycemia has also a negative impact: for every unit increase, the chance of better outcome decreases by 24%. Higher initial ASPECTS score is associated with better outcomes: each point increase of ASPECTS score at initial evaluation, increases the chance of better outcome by 154.2%.

Conclusion

Males, older age, diabetes, and hyperglycemia correlate with a worse outcome after cerebral stroke regardless of the benefit yielded fibrinolytic and/or thrombectomy therapy. In this study, patients with the above-mentioned factors did not improve more than 30% of baseline NIHSS score from admission to the 7th day.

The correlation between novel peripheral blood cell ratios and 90-day mortality in patients with acute ischemic stroke

BACKGROUND

We aimed to investigate the correlation between the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), platelet-to-neutrophil ratio (PNR), platelet-to-white blood cell ratio (PWR) and 90-day mortality in patients with acute ischemic stroke (AIS).

METHODS

We retrospectively included 633 patients with AIS from January 2017 to May 2018. The correlation between each indicator and the degree of neurologic deficit was assessed. Kaplan-Meier survival curves based on blood cell ratios were used to analyze the 90-day survival rate of patients with AIS.

RESULTS

A total of 663 patients with AIS were enrolled, of which 24 (3.6%) experienced recurrence and 13 (2.0%) died. NLR>3.23 (odds ratio; OR = 2.236; 95% confidence interval [CI], 1.472-3.397; P<0.001), PNR<31.14 (OR = 0.471; 95% CI, 0.297-0.749; P = 0.001), and PWR<20.62 (OR = 0.498; 95% CI, 0.309-0.800; P = 0.004) were associated with an unfavorable 90-day prognosis. NLR>3.23, PWR<20.62, and PNR<31.14 were associated with an increased risk of 90-day mortality.

CONCLUSION

PNR, PWR, and NLR were associated with the 90-day mortality of patients with AIS. Patients with high NLRs or low PWRs and PNRs may have a greater risk of mortality than other patients. These clinical indicators may help clinicians judge unfavorable prognosis early and implement the appropriate interventions.

The relationship between the platelet to leukocyte ratio and mechanical thrombectomy outcomes in acute ischemic stroke patients

BACKGROUND AND PURPOSE

The predictive effect of blood cell ratio on ischemic event has been widely confirmed. Whether PWR and PNR can assess the risk of endovascular treatment (EVT) is largely unclear. This study aimed to investigate the prognostic value of PNR and PWR in acute ischemic stroke patients treated with EVT.

METHODS

Poor functional outcome was defined as Modified Rankin Scale (mRS) of 3-6 at 3 months, Symptomatic intracranial hemorrhage (sICH) was diagnosed based on CT scan and classified according to the criterial of Heidelberg Bleeding Classification. Binary logistical regression was used to analyze the relationship of PWR, PNR with functional outcome and symptomatic intracranial hemorrhage (sICH).

RESULTS

Patients with good prognosis had higher PNR and PWR value (29 vs. 24, P=0.002) (22 vs. 19, P=0.009), a lower rate of sICH (2.9% vs. 24.9%, P<0.001). In model 1, the lower PNR significantly associated with poor functional outcome (OR, 0.48; 95% CI 0.26-0.88; P=0.018), and sICH (OR, 0.42; 95% CI 0.19-0.91; P=0.028). The lower PWR only significantly associated with poor prognosis (OR, 0.97; 95% CI 0.94-1.00; P=0.038), and had a trend relation with sICH (OR, 0.98; 95% CI 0.94-1.02; P=0.328). In model 2 lower PNR still significantly associated with poor functional outcome (OR, 0.53; 95% CI 0.29-0.99; P=0.047), but showed a trend for predicting sICH (OR, 0.56; 95% CI 0.25-1.25; P=0.158).

CONCLUSION

Platelet to leukocyte ratio may be use to assess the risk of functional outcome and sICH in patients with acute anterior circulation occlusion stroke undergoing endovascular treatment in real world China.

Thrombocytopenia and platelet course on hospital mortality in neurological intensive care unit: a retrospective observational study from large database

BACKGROUND

Thrombocytopenia (TP) has been shown to be an independent predictor of mortality in the intensive care unit (ICU) patients. Studies are lacking in the neurological ICU (NICU) population. The aim was to evaluate the incidence of TP in NICU and the relationship between TP and outcomes.

METHODS

We conducted a retrospective multicenter study of prospectively collected data of all patients admitted to the NICU between 2014 and 2015 from a large database (eICU Collaborative Research Database). The main exposure was TP at admission and TP developed during NICU stay. Multivariable logistic regression and Cox proportional hazard models were used to evaluate the relationship of TP at admission and platelet course with hospital mortality. The primary outcome was hospital mortality.

RESULTS

7450 patients in NICU from 17 hospitals were included. Hospital mortality was 9%. TP at admission was present in 20% of patients, TP developed during NICU stay was present in 13.2% of patients. TP at admission was not associated with hospital mortality after adjusting for confounders (OR 1.14 [95% CI 0.92-1.41, p = 0.237]). Hospital mortality of continuous TP during NICU stay was 15% while hospital mortality of recovery from TP at admission was 6% (p < 0.001). Patients with TP developed during NICU stay had higher odds ratio for hospital mortality (OR 1.65 [95% CI 1.3-2.09, p < 0.001]).

CONCLUSIONS

Thrombocytopenia is common in NICU and patients who have thrombocytopenia not resolving have increased mortality. Patients' recovery from thrombocytopenia may predict a good prognosis.

Platelet Responses in Cardiovascular Disease: Sex-Related Differences in Nutritional and Pharmacological Interventions

Cardiovascular diseases (CVD) represent one of the biggest causes of death globally, and their prevalence, aetiology, and outcome are related to genetic, metabolic, and environmental factors, among which sex- and age-dependent differences may play a key role. Among CVD risk factors, platelet hyperactivity deserves particular mention, as it is involved in the pathophysiology of main cardiovascular events (including stroke, myocardial infarction, and peripheral vascular injury) and is closely related to sex/age differences. Several determinants (e.g., hormonal status and traditional cardiovascular risk factors), together with platelet-related factors (e.g., plasma membrane composition, receptor signaling, and platelet-derived microparticles) can elucidate sex-related disparity in platelet functionality and CVD onset and outcome, especially in relation to efficacy of current primary and secondary interventional strategies. Here, we examined the state of the art concerning sex differences in platelet biology and their relationship with specific cardiovascular events and responses to common antiplatelet therapies. Moreover, as healthy nutrition is widely recognized to play a key role in CVD, we also focused our attention on specific dietary components (especially polyunsaturated fatty acids and flavonoids) and patterns (such as Mediterranean diet), which also emerged to impact platelet functions in a sex-dependent manner. These results highlight that full understanding of gender-related differences will be useful for designing personalized strategies, in order to prevent and/or treat platelet-mediated vascular damage.

Risk Profile of Ischemic Stroke Caused by Small-Artery Occlusion vs. Deep Intracerebral Hemorrhage

Background: Small-artery occlusion (SAO) subtype accounts for a quarter of the cases of ischemic stroke and is mainly caused by pathological changes in cerebral small vessels, which also involve in deep intracerebral hemorrhage (dICH). However, the factors that drive some cases to SAO and others to dICH remained incompletely defined. Material and Methods: This study is a cross-sectional study from the China National Stroke Registry that included consecutive patients with ischemic stroke or intracerebral hemorrhage between August 2007 and September 2008. We compared the risk profile between the two subgroups using multivariable logistic regression. Results: A total of 1,135 patients with SAO stroke and 1,125 dICH patients were included for analyses. Generally, patients with SAO stroke were more likely to be male (odds ratio = 0.74, confidence interval = 0.58-0.94) and have diabetes (0.30, 0.22-0.40), higher atherogenic lipid profiles, higher body mass index (0.96, 0.94-0.99), higher waist/height ratio (0.12, 0.03-0.48), higher platelet count (0.84, 0.77-0.91), and higher proportion of abnormal estimated glomerular filtration rate (<90, ml/min/1.73 m²) (0.77, 0.62-0.95). Conversely, patients with dICH were more likely to have higher blood pressure parameters, inflammation levels (white blood cell count: 1.61, 1.48-1.76; high sensitivity C-reactive protein: 2.07, 1.36-3.16), and high-density lipoprotein-c (1.57, 1.25-1.98). Conclusions: The risk profile between SAO stroke and dICH were different. Furthermore, despite of traditional indexes, waist/height ratio, platelet count, inflammation levels, lipid profile, and estimated glomerular filtration rate also play important roles in driving arteriolosclerosis into opposite ends.

Impact of hemoglobin concentration and platelet count on outcomes of patients with non-valvular atrial fibrillation: A subanalysis of the J-RHYTHM Registry

BACKGROUND

To clarify the influence of hemoglobin concentration and platelet count on adverse outcomes of Japanese patients with non-valvular atrial fibrillation (NVAF), a post hoc analysis of the J-RHYTHM Registry was performed.

METHODS

A consecutive series of outpatients with atrial fibrillation were enrolled from 158 institutions and followed up for 2 years or until an event occurred (thromboembolism, major hemorrhage, or all-cause death). Among 7406 patients with NVAF, 6536 with complete blood count data (69.8 ± 9.9 years, 71.0% men) were divided into 4 groups according to the baseline hemoglobin level (<10.0, 10.0-11.9, 12.0-13.9, and ≥14.0 g/dL) or platelet count (<10.0, 10.0-19.9, 20.0-29.9, and ≥30.0 × 10⁴/μL).

RESULTS

Incidence rates of major hemorrhage (p = 0.004 for trend), all-cause death (p < 0.001 for trend), and composite events (p < 0.001 for trend) increased as hemoglobin levels decreased, and composite events (p = 0.045 for trend) increased as platelet counts decreased. After adjusting for multiple confounders, the incidence of all-cause death and composite events was higher with hemoglobin levels <12.0 g/dL than a hemoglobin level ≥14.0 g/dL. In contrast, platelet count was not associated with any events. This was also true when multivariate analysis was performed using the stepwise forward method.

CONCLUSIONS

A low hemoglobin level (<12.0 g/dL) was an independent risk factor for all-cause death and composite events in Japanese patients with NVAF. However, platelet count did not impact outcomes.

CLINICAL TRIAL REGISTRATION

http://www.umin.ac.jp/ctr/ (unique identifier: UMIN000001569).

Platelet count and mean volume in acute stroke: a systematic review and meta-analysis

Changes of mean platelet volume (MPV) and platelet count (PC) could be a marker or a predictor of acute stroke (AS). We conducted a systematic review and meta-analysis of the published literature on the reporting of MPV and PC in AS. Studies were included in accordance with Patient Population or Problem, Intervention, Comparison, Outcomes, and Setting framework. The PRISMA strategy was used to report findings. Risk of bias was assessed with the Newcastle-Ottawa Scale. We included 34 eligible articles retrieved from the literature. PC was significantly lower in AS patients [standardized mean difference (SMD) = - 0.30, (95% CI: - 0.49 to - 0.11), N = 2492, P = .002] compared with controls (N = 3615). The MPV was significantly higher [SMD = 0.52 (95% CI: 0.28-0.76), N = 2739, P < .001] compared with controls (N = 3810). Subgroup analyses showed significantly lower PC in both ischemic stroke (Difference SMD = -0.18, 95% CI: -0.35-0.01) and hemorrhagic stroke (-0.94, -1.62 to -0.25), but only samples by citrate anticoagulant showed significantly lower result for patients compared to controls (-0.36, -0.68 to -0.04). Ischemic stroke patients had higher MPV (0.57, 0.31-0.83), and samples by Ethylenediaminetetraacetic acid (EDTA) anticoagulant showed significantly higher result for patients compared to controls (0.86, 0.55-1.17). PC and MPV appeared to be significantly different between patients with AS and control populations. MPV was significantly higher in ischemic stroke and PC was significantly lower in both ischemic and hemorrhagic strokes. These characteristics might be related to AS and associated with it. It is advisable to pay attention to elapsed time between phlebotomy and hematology analysis, anticoagulant and hemocytometer types in AS.

SYSTEMATIC REVIEW REGISTRATION

This meta-analysis is registered on the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42017067864 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=67864).

Predictive and prognostic role of mean platelet volume in patients with first-ever acute ischemic stroke

Objective:

To investigate any possible effects of mean platelet volume (MPV) on short-term stroke prognosis and functional outcome in patients with first-ever acute ischemic stroke (FEAIS).

Methods:

This retrospective cross-sectional study included 798 FEAIS patients admitted to the emergency department of a tertiary care hospital in Adiyaman, Turkey between January 2013 and June 2015. The data were evaluated according to whether alive or dead, MPV levels, modified Rankin scale (MRS) scores, National Institutes of Health Stroke Scale (NIHSS) scores. The patients were divided into 3 groups based on MPV level as 4.4-7.4 fL, 7.5-10.4 fL, higher than 10.4 fL.

Results:

A total of 250 patients with FEAIS were included in the study. In both those who survived and those who died, the area under the curve related to hospitalization days, time interval of venipuncture (TIV), and MPV measurements was not statistically significant (p>0.05). The 3 MPV groups showed no significant differences in terms of MRS score, median NIHSS score, hospitalization, and TIV. In subgroups based on MRS scores, there were no statistically significant differences according to median latency (p=0.087), median hospitalization (p=0.394), TIV (p=0.201), and MPV levels (p=0.847). Furthermore, there were no differences in MPV levels between the MRS based groups (p=0.527).

Conclusion:

The results showed that MPV was not a significantly associated and reliable marker for the prediction of prognosis or functional outcome of FEAIS attack.

Thrombocytopenia and declines in platelet counts: predictors of mortality and outcome after mechanical thrombectomy

BACKGROUND AND PURPOSE

Acute ischemic stroke (AIS) has well-known risk factors. The role of platelets in patients treated using mechanical thrombectomy (MT) has not been studied. The aim of this study was to study if there is an association of initial thrombocytopenia (TP) and a decline of platelets counts (DPC) with the clinical outcomes, mortality and intracranial hemorrhage (ICH) rates in AIS patients treated with MT.

MATERIALS AND METHODS

In a case-control study consecutive MT-stroke patients were analyzed. A multivariate logistic regression model was used to test for good clinical outcome (mRS 90 days <= 2) and mortality adjusting for age, initial NIHSS, pretreatment with tPA, statins and platelet inhibitors, occlusion site, time from symptom onset to recanalization, initial TP (< 150 × 10⁹/L) and DPC (> 26%). Additionally, rates of ICH were compared.

RESULTS

Of 294 patients included, 9.6% had an initial TP and 23.8% a DPC > 26%. The mortality rate in patients with normal platelet counts was 26.1% vs. 48.3% (p = 0.002) in patients with initial TP with an aOR of 3.47 (CI 1.28-9.4, p = 0.005). No difference regarding the rate of good clinical outcome (p = 0.204) and ICH (p = 0.18) was observed. A DPC of more than 26% during the first 5 days of hospitalization predicted the rate of mortality (aOR 2.4 CI 1.14-5.04, p = 0.021) and the chances of a good clinical outcome (aOR 0.291 CI 0.128-0.666, p = 0.003) without significant differences of ICH rates (p = 0.735).

CONCLUSION

In AIS patients treated with MT an initial TP was independently associated with higher mortality rates and a marked DPC with higher mortality rates as well as poorer clinical outcomes.

The mean platelet volume on admission predicts unfavorable stroke outcomes in patients treated with IV thrombolysis

Purpose

The role of biomarkers in the prediction of acute ischemic stroke (AIS) outcome or response to thrombolytic therapy (with recombinant tissue plasminogen activator [rt-PA]) remains limited. The aim of this study was to evaluate whether mean platelet volume (MPV) could predict short-term functional outcome in patients with AIS following rt-PA treatment.

Patients and methods

This was a retrospective analysis of 237 AIS patients (mean age 71.04±0.8 years, 50.6% women) consecutively admitted to a tertiary care center between 2011 and 2015.

Results

The mean MPV in the cohort was 9.8±0.35 fL (lowest tertile <7.29 fL, median 7.29–8.8 fL, and highest tertile >8.8 fL). Patients in the lowest tertile compared to median and highest tertiles were less often dependent (modified Rankin scale [mRS] ≥3) at admission (87.2% vs 96.1% and 96.1%, respectively, P=0.04) and less often had a poor stroke outcome (mRS 4–6) at discharge (28.2% vs 55.3% and 44.7%, P<0.01). However, there was no significant difference between tertiles with regard to AIS etiology, CT (Alberta Stroke Program Early CT) score, frequency of stroke due to large artery occlusion, risk of secondary hemorrhage, and early neurologic deterioration. Multivariable analysis after adjustment for confounders showed that patients in the second and third tertiles had a significantly higher risk of poor stroke outcome (OR =1.9, 95% CI =1.01–4), lack of early improvement (OR =1.91, 95% CI =1.05–3.47), lower chance of good outcome (mRS 0–2; OR =0.38, 95% CI =0.18–0.78), or minor stroke at discharge (OR =0.47, 95% CI =0.26–0.84). Receiver operating characteristic analysis for prediction of poor stroke outcome showed that the optimal cut-off point of MPV was 8.8 fL (area under the curve 0.586 [0.512–0.659], P=0.03) with a sensitivity of 82.7% and a specificity of 43.9%.

Conclusion

Disabling or fatal ischemic stroke in thrombolyzed patients was observed more often in patients with high admission MPV. The prognostic value of MPV was independent of other well-defined individual risk factors.

The mean platelet volume and plateletcrit as predictors of short-term outcome of acute ischemic stroke

Background

Activation of the platelet plays an important role in the process of atherosclerosis. Mean platelet volume (MPV) is significantly associated with the poor outcome of acute ischemic stroke while the results of studies about the relationship between plateletcrit (PCT) and stroke outcome were inconsistent. The aim of this work is to determine whether an association exists between MPV and plateletcrit (PCT) and outcome of acute ischemic stroke.

Methods

We examined 157 patients with ischemic stroke, admitted to the Sohag University Hospital. The diagnosis of stroke was performed clinically according to The World Health Organization and confirmed by brain CT and MRI when needed. Platelet indices including MPV and PCT were assessed immediately (within 2 h) after admission. After 3 months, the functional outcome was assessed using the modified Rankin Scale (mRS) with assessment of the relationship between platelet indices and stroke outcome.

Results

About 50% of the participants have favorable outcome. MPV was significantly higher in the unfavorable group (10.4 ± 2.3 fL) than in the favorable one (8.7 ± 1.3 fL) (P < 0. 001). MPV was an independent predictor of poor short-term outcome of acute stroke after controlling for confounders like diabetes mellitus. The mean PCT was significantly higher in the unfavorable group (0.28 ± 0.1%) than in the favorable one (0.25 ± 0.1%) (P = 0. 04) but not considered as an independent predictor of poor short-term outcome of acute stroke.

Conclusions

MPV and PCT were significantly correlated with poor functional outcome, only MPV was an independent predictor of poor short-term outcome of acute stroke after controlling for confounders like DM, and these platelet indices can be used as a prognostic tool.

Towards stroke prediction using electronic health records

Background

As of 2014, stroke is the fourth leading cause of death in Japan. Predicting a future diagnosis of stroke would better enable proactive forms of healthcare measures to be taken. We aim to predict a diagnosis of stroke within one year of the patient’s last set of exam results or medical diagnoses.

Methods

Around 8000 electronic health records were provided by Tsuyama Jifukai Tsuyama Chuo Hospital in Japan. These records contained non-homogeneous temporal data which were first transformed into a form usable by an algorithm. The transformed data were used as input into several neural network architectures designed to evaluate efficacy of the supplied data and also the networks’ capability at exploiting relationships that could underlie the data. The prevalence of stroke cases resulted in imbalanced class outputs which resulted in trained neural network models being biased towards negative predictions. To address this issue, we designed and incorporated regularization terms into the standard cross-entropy loss function. These terms penalized false positive and false negative predictions. We evaluated the performance of our trained models using Receiver Operating Characteristic.

Results

The best neural network incorporated and combined the different sources of temporal data through a dual-input topology. This network attained area under the Receiver Operating Characteristic curve of 0.669. The custom regularization terms had a positive effect on the training process when compared against the standard cross-entropy loss function.

Conclusions

The techniques we describe in this paper are viable and the developed models form part of the foundation of a national clinical decision support system.

Genetically Determined Platelet Count and Risk of Cardiovascular Disease

Objective- Cardiovascular disease, including coronary artery disease (CAD) and ischemic stroke, is the leading cause of death worldwide. This Mendelian randomization study uses genetic variants as instruments to investigate whether there is a causal effect of genetically determined platelet count on CAD and ischemic stroke risk. Approach and Results- A genome-wide association study of 166 066 subjects was used to identify instruments and genetic association estimates for platelet count. Genetic association estimates for CAD and ischemic stroke were obtained from genome-wide association studies, including 60 801 CAD cases and 123 504 controls, and 60 341 ischemic stroke cases and 454 450 controls, respectively. The inverse-variance weighted meta-analysis of ratio method Mendelian randomization estimates was the main method used to obtain estimates for the causal effect of genetically determined platelet count on risk of cardiovascular outcomes. We found no significant Mendelian randomization effect of genetically determined platelet count on risk of CAD (odds ratio of CAD per SD unit increase in genetically determined platelet count, 1.01; 95% CI, 0.98-1.04; P=0.60). However, higher genetically determined platelet count was causally associated with an increased risk of ischemic stroke (odds ratio, 1.07; 95% CI, 1.04-1.11; P<1×10-5), including all major ischemic stroke subtypes. Similar results were obtained in sensitivity analyses more robust to the inclusion of pleiotropic genetic variants. Conclusions- This Mendelian randomization study found evidence that higher genetically determined platelet count is causally associated with higher risk of ischemic stroke.

Genetics of platelet traits in ischaemic stroke: focus on mean platelet volume and platelet count

Purpose/Aim of the study: The aim of this review is to summarize the role of genetic variants affecting mean platelet volume (MPV) and platelet count (PLT) leading to higher platelet reactivity and in turn to thrombotic events like stroke and cardiovascular diseases.

MATERIALS AND METHODS

A search was conducted in PUBMED, MEDLINE, EMBASE, PROQUEST, Science Direct, Cochrane Library, and Google Scholar related to the studies focussing on genome-wide association studies (GWAS), whole exome sequencing (WES), whole genome sequencing (WGS), phenome-wide association studies (PheWAS) and multi-omic analysis that have been employed to identify the genetic variants influencing MPV and PLT.

RESULTS

Antiplatelet agents underscore the crucial role of platelets in the pathogenesis of stroke. Higher platelet reactivity in terms of mean platelet volume (MPV) and platelet count (PLT) contributes significantly to the interindividual variation in platelet reaction at the site of vessel wall injury. Some individuals encounter thrombotic events as platelets get occluded at the site of vessel wall injury whereas others heal the injury without occluding the circulation. Evidence suggests that MPV and PLT have a strong genetic component. High throughput techniques including genome-wide association studies (GWAS), whole exome sequencing (WES), whole genome sequencing (WGS), phenome-wide association studies (PheWAS) and multi-omic analysis have identified different genetic variants influencing MPV and PLT.

CONCLUSIONS

Identification of complex genetic cross talks affecting PLT and MPV might help to develop novel treatment strategies in treating neurovascular diseases like stroke.

Early prediction of severity in acute ischemic stroke and transient ischemic attack using platelet parameters and neutrophil-to-lymphocyte ratio

BACKGROUND

It is still not easy to predict severity promptly in patients with acute ischemic stroke (AIS) and transient ischemic attack (TIA). We investigated that platelet parameters or combinations of them could be a useful tool for early prediction of severity of AIS and TIA at admission and after 3 months.

METHODS

We prospectively recruited 104 patients newly diagnosed with AIS and TIA. We investigated their neutrophil-to-lymphocyte ratio (NLR) and platelet parameters. According to the Modified Rankin Scale scores, the patients were divided into two groups.

RESULTS

In receiver operating characteristic (ROC) curve analyses, mean platelet volume (MPV), NLR/platelet count (PLT), MPV/PLT, MPV*NLR, and MPV*NLR/PLT showed statistically significant results in both at admission and after 3 months. Values of area under ROC curves for those tests at admission were 0.646, 0.697, 0.664, 0.708, and 0.722, respectively. Also, values after 3 months were 0.591, 0.661, 0.638, 0.662, and 0.689, respectively.

CONCLUSION

MPV*NLR/PLT could be used as a relatively good tool for predicting severity at the time of admission and after 3 months than other parameters or combinations of them. Further studies have to be carried out to investigate the best parameter for predicting the severity of AIS and TIA.

Prognostic efficacy of platelet count in patients with nonvalvular atrial fibrillation

BACKGROUND

The prognostic efficacy of quantitative platelet activity in atrial fibrillation (AF) remains unclear.

OBJECTIVE

The purpose of this study was to evaluate the platelet count (PLT) as a prognostic indicator in patients with nonvalvular AF.

METHODS

Data on 10,978 patients with nonvalvular AF were retrieved from a prospective registry of a single medical center in Korea. Cumulative risk for stroke and bleeding events were compared between patients with normal PLT (n = 8322), mild thrombocytopenia (n = 1791), and moderate to severe thrombocytopenia (n = 865) after propensity score matching. Prediction models for stroke were derived by conventional risk factors (model 1) and by combining PLT with model 1 (model 2), and model performance was assessed by area under the receiver operator characteristics curve (AUC).

RESULTS

During the follow-up period, 7.3%, 7.0%, and 4.5% had stroke and 7.6%, 10.8%, and 17.2% had bleeding events in the normal PLT, mild, and moderate to severe thrombocytopenia groups, respectively. Compared to the normal PLT group, the moderate to severe thrombocytopenia group showed a lower risk of stroke (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.40-0.80; P = .002). A reverse relationship was found between PLT and bleeding risk (moderate to severe thrombocytopenia: HR 2.19; 95% CI 1.77-2.70; P <.001; mild thrombocytopenia: HR 1.43; 95% CI 1.18-1.73; P <.001). Compared to model 1, model 2 showed significant improvement in risk prediction (AUC 0.628 vs 0.644; P <.001).

CONCLUSION

A lower PLT was associated with a lower risk of stroke and a higher risk of bleeding events. PLT combined with conventional risk factors showed significant improvement in prediction for stroke.

Platelet count is associated with outcome in cancer patients with stroke

INTRODUCTION

Cerebrovascular disease (CVD) and cancer are among the most common causes of mortality worldwide, preceded only by ischemic heart disease (IHD). Thrombocytopenia was shown to be associated with poor outcomes in IHD and CVD in the general population. This study aimed to assess the relationship of thrombocytopenia with poor outcomes in cancer patients with CVD.

MATERIALS AND METHODS

Data on patients with concomitant CVD and cancer who were initially treated at a cancer referral center between January 2010 and December 2017 were included. Thrombocytopenia was defined as a platelet count < 150,000/mm³ during the first 24 h of CVD symptom onset. The IRB (CI/837/17) approved the review of clinical records.

RESULTS

Among 268 cancer patients with CVD included in the study, 210 met the inclusion criteria. Median overall survival of the entire cohort was 7.2 months, which was significantly shorter in males (p = 0.029) and patients with hematologic tumors (p = 0.009), hemorrhagic CVD (p < 0.001), altered mental status (p < 0.001), and thrombocytopenia (p < 0.001). Multiple regression logistic analysis revealed that thrombocytopenia (risk ratio [RR] 1.6, 95% confidence interval [CI] 1.1-2.4) and altered mental status (RR 2.7, 95% CI 1.9-4.0) remained statistically significant risk factors for mortality.

CONCLUSION

In cancer patients with CVD, thrombocytopenia at the time of CVD diagnosis and altered mental status during initial clinical evaluation were associated with higher mortality, which should be confirmed in future studies.

The HindIII and PvuII polymorphisms of lipoprotein lipase (LPL) gene reduce the risk of ischemic stroke (IS): A meta-analysis

BACKGROUND

Lipoprotein lipase (LPL) polymorphisms were suggested to be the risk factor for ischemic stroke (IS). However, controversial results were obtained. Our objective was to investigate the association of LPL polymorphisms at Ser447Ter, HindIII (+/-), and PvuII (+/-) with IS risk.

METHODS

Literatures search were carried out on databases: PubMed, Web of science, the Cochrane database of system reviews, Chinese National Knowledge Infrastructure, and Embase. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to detect the relationship between LPL polymorphisms and the risk of IS.

RESULTS

No significant association was detected between LPL Ser447Ter and IS in allelic, dominant, or recessive models (P > .05). Significant lower frequencies of allelic and dominant models of LPL HindIII (+/-) and PvuII (+/-) in cases were detected (HindIII (+/-): allelic model: P = .0002, OR[95%CI] = 0.80 [0.71, 0.90]; dominant model: P = 0.003, OR[95%CI] = 0.80 [0.69, 0.92]; PvuII (+/-): allelic model: P < 0.0001, OR[95%CI] = 0.75[0.65-0.86]; dominant model: P = 0.02, OR[95%CI] = 0.67[0.48-0.93]). And the recessive model of PvuII (+/-) was significantly associated with the IS risk (P = .01, OR[95%CI] = .71[0.55-0.93]). Subgroup analysis stratified by ethnicity showed that the frequencies of allelic, dominant, and recessive models of HindIII (+/-), as well as dominant model of PvuII (+/-) were significant lower in Asian cases (HindIII (+/-): allelic model: P < .00001, OR[95%CI] = 0.69 [0.59, 0.79]; dominant model: P < .0001, OR[95%CI] = 0.69 [0.58, 0.83]; recessive model: P = .005, OR[95%CI] = 0.66 [0.50, 0.89]; PvuII (+/-): dominant model: P = .0008, OR[95%CI] = 0.66 [0.51-0.84]), but not in Caucasian cases (P > .05). In addition, the frequencies of allelic and recessive models of PvuII (+/-) significantly decreased in Caucasian cases (P < .05).

CONCLUSION

the HindIII (+/-) and PvuII (+/-), but not the Ser447Ter might be the protective factors for IS.

A retrospective analysis of cases with neuroleptic malignant syndrome and an evaluation of risk factors for mortality

Objective

Neuroleptic malignant syndrome (NMS) is a neurological emergency rarely encountered in clinical practice but with a high mortality rate. Cases associated with atypical antipsychotic use or termination of dopamine agonists have been seen in recent years. The purpose of this study was to assess the presence of risk factors for mortality by investigating all clinical and laboratory characteristics of cases with NMS.

Material and methods

This descriptive, cross-sectional study retrospectively investigated all clinical and laboratory characteristics by scanning the ICD-10 codes of patients presenting to the XXXX Faculty of Medicine Emergency Department and diagnosed with NMS between 2006 and 2016. Patients were divided into surviving and non-surviving groups, and the data elicited were subjected to statistical comparisons.

Results

The mean age of the 18 patients diagnosed with NMS was 46.9 ± 4.8 years, and 50% were women. In addition to antipsychotics among the drugs leading to NMS, the syndrome also developed as a result of levodopa withdrawal in three patients and metoclopramide use in one patient. Statistically significant differences were determined between the surviving and non-surviving patients in terms of blood pressure, blood urea nitrogen (BUN), creatine kinase (CK) and mean platelet volume (MPV) values (p ≤ 0.05).

Conclusion

In this study the most common agent that cause NMS was atypical antipsychotics. Also advanced age, increased blood pressure and serum CK, BUN and MPV values were identified as potential risk factors for mortality in NMS.

Assessment of red blood cell distribution width and mean platelet volume in children with epistaxis

OBJECTIVE

This study aimed to investigate whether there is a relationship between red blood cell distribution width, mean platelet volume and epistaxis in children.

METHODS

Between January 2015 and July 2016, 105 children who were referred to our clinic with epistaxis and 100 sex- and age-matched controls were retrospectively analyzed. Red blood cell distribution width (RDW) and mean platelet volume (MPV) values were determined in both groups.

RESULTS

RDW values were found significantly (P < 0.05) lower in the group with epistaxis than in the control group (11.95 ± 1.31 vs. 12.74 ± 1.21). MPV was 7.49 ± 1.33 in the group with epistaxis and 7.23 ± 1.06 in the control group, and there was no significant difference between the groups (p > 0.05).

CONCLUSION

We found no difference between MPV values of both groups and significantly lower RDW values in children with epistaxis. Decreased RDW values were considered as an accompanying marker rather than a result of epistaxis. In addition, it may be thought that low RDW values may increase the bleeding tendency by disrupting the thrombotic activities. Further studies are needed to validate the relation of these parameters with epistaxis and its mechanisms.

Platelet genomics: the role of platelet size and number in health and disease

Taken together, there is ample evidence of the association of cardiovascular disease, cerebrovascular, and inflammatory disease with single nucleotide variants (SNV) due to their impact on platelet size, number, and function. With the use of electronic medical record (EMR) or other phenotypic-linked bioinformatics sources, the more important "functional" variants are emerging and provide valuable information on their specific role in promoting early onset of disease or poor response to therapeutic measures. This review will focus upon the recognized common polymorphisms or gene variants with small, but functional effects, as it is becoming clear that these contribute to hyper- or hypo-responsive platelet phenotypes. The impact of these gene variants is distinguishable among normal individuals, and they are suspected contributors to increased risk of adverse outcomes in patients with underlying disease. There are thousands of gene variants and environmental factors that may mitigate risk or amplify the potential for disease within each of us. When combined with the environment and epigenetic influences, it is clear that whole-genome sequencing and bioinformatics alone will not be enough to truly predict "risk" or probability, but awareness of their potential influence may be a starting point in selective screening and generating prevention strategies to promote a healthy lifestyle or fine-tune therapeutic choices in the future.