Association of mean platelet volume with risk of stroke among 3134 individuals with history of cerebrovascular disease

Inflammation, Autoimmunity, and Infection in Fibromyalgia: A Narrative Review

Fibromyalgia (FM) is a chronic disease characterized by widespread musculoskeletal pain of unknown etiology. The condition is commonly associated with other symptoms, including fatigue, sleep disturbances, cognitive impairment, and depression. For this reason, FM is also referred to as FM syndrome. The nature of the pain is defined as nociplastic according to the latest international classification and is characterized by altered nervous sensitization both centrally and peripherally. Psychosocial conditions have traditionally been considered critical in the genesis of FM. However, recent studies in animal models and humans have provided new evidence in favor of an inflammatory and/or autoimmune pathogenesis. In support of this hypothesis are epidemiological data of an increased female prevalence, similar to that of autoimmune diseases, and the frequent association with immune-mediated inflammatory disorders. In addition, the observation of an increased incidence of this condition during long COVID revived the hypothesis of an infectious pathogenesis. This narrative review will, therefore, discuss the evidence supporting the immune-mediated pathogenesis of FM in light of the most current data available in the literature.

Evaluation of mean platelet volume and platelet count in ischemic stroke and its subtypes: focus on degree of disability and thrombus formation

Background: Platelets are crucial players in thrombus formation during ischemic stroke. Platelet (PLT) count and Mean platelet volume (MPV) are important parameters that affect platelet functions. The current study has been carried out with an aim to evaluate the association of MPV and PLT count with ischemic stroke in a population from the Malwa region of Punjab.

Material and Methods: The study included one hundred and fifty ischemic stroke patients. The extent of disability occurs by stroke was measured by mRS. MPV and PLT was evaluated using cell counter. Further, PLT count was confirmed in 50% of patients using flow cytometer. Clot formation rate was evaluated using Sonoclot Coagulation and Platelet Function Analyzer. All the statistical analysis was carried out using SPSS.

Results: A significant association of increased MPV (p < 0.02) was found with the ischemic stroke. However, PLT count did not show a significant association with the disease (p < 0.07). Further, a stepwise multiple logistic regression (MLR) analysis controlling the other confounding risk factors evaluated the association of hypertension and MPV with the disease. Patients with higher mRS were found to have high MPV values confirming that higher MPV is correlated with disability occurs by ischemic stroke. MPV was also found to be significantly associated with large artery atherosclerosis (p < 0.001). Clot formation analysis revealed that ischemic stroke patients bear higher clot rate (CR) and Platelet function (PF) values.

Conclusions: Elevated MPV is an independent risk factor for Ischemic stroke along with hypertension. In addition, higher MPV associated significantly with stroke disability as well.

Platelet Parameters as Biomarkers for Thrombosis Risk in Cancer: A Systematic Review and Meta-analysis

Cancer-associated thrombosis (CAT) is a major cause of both morbidity and mortality in cancer patients. Platelet count has been investigated as a predictor of CAT in various settings while knowledge on platelet activation parameters is sparse. This report provides a systematic review and meta-analysis on available literature on associations between platelet count and/or function and arterial and venous thrombosis in adult cancer patients. The review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. PubMed and Embase were searched up to March 2022. The National Heart, Lung, and Blood Institute's tools were used for quality assessment. In total, 100 studies were included which investigated the association between CAT and platelet count (n = 90), platelet indices (n = 19), and platelet function/activation markers (n = 13) in patients with solid cancers (n = 61), hematological cancers (n = 17), or mixed cancer types (n = 22). Eighty-one studies had venous thrombosis as their outcome measure, while 4 had arterial thrombosis and 15 studies had both. We found significantly elevated odds ratio of 1.50 (95% confidence interval: 1.19-1.88) for thrombosis with higher platelet counts. We saw a tendency toward an association between markers of platelet activation in forms of mean platelet volume and soluble P selectin and both arterial and venous thrombosis. Only one study investigated dynamic platelet function using flow cytometry. In conclusion, platelet count is associated with CAT across different cancer types and settings. Platelet function or activation marker analysis may be valuable in assisting thrombosis risk assessment in cancer patients but is sparsely investigated so far.

Platelet indices as prognostic markers of ischemic stroke and their correlation with lipid profile

OBJECTIVE

Stroke is the cause of one in eight deaths and adds a dreadful burden of disability for the patients. Ischemic stroke is caused by a loss of blood supply to brain due to sudden occlusion of the arterial system, caused by an emboli or thrombus. Our aim was to correlate platelet indices, total cholesterol ratio, and various comorbidities with stroke.

METHODS

A cross-sectional study was performed from 2020-2022 with 132 stroke patients admitted to the SRM Medical College Hospital and Research Center, India. Detailed clinical examination was performed. Venous blood samples were drawn at the time of admission to estimate platelet count, mean platelet volume (MPV), platelet distribution width (PDW), and platelet crit (PCT). Overnight fasting serum samples were obtained for lipid profiling.

RESULTS

Among the participants in our study, maximum belonged to the age group 50 to 59 years (34.1%) and majority were males (79.5%). In terms of comorbidities, 85.6% of the participants had diabetes, 42.4% had hypertension and 22% had dyslipaedemia. All platelet and lipid parameters were found to be similar between patients with and without comorbidities. While all platelet indices increased with the increase in severity of stroke, we found that PDW is most reliable in predicting stroke with an area under the receiver operator curve of 0.942, with a sensitivity and specificity of 92.1% at cut-off value 14. All platelet parameters also significantly increased in patients with severe lipid dysfuction, establishing a correlation between lipid profile, platelet indices and stroke.

CONCULSION

We found a significant relationship between all platelet parameters and stroke. Thus, we believe that patients with risk factors for atherosclerosis should have their platelet indices assessed periodically before the development of cerebrovascular events. Furthermore, dyslipidemia if properly treated, is a modifiable risk factor for stroke, which can decrease morbidity and mortality leading to a healthier society.

Is dynamic change in mean platelet volume related with composite endpoint development after transcatheter aortic valve replacement?

Aortic valve stenosis (AS) is the most common valvular disease, and surgical or transcatheter aortic valve replacement (TAVR) are the treatment options. Diminish in platelet production or dysfunction may occur due to shear stress, advanced age, and other coexisting diseases in AS patients. Bleeding is one of the complications of TAVR and associated with increased mortality. MPV (mean platelet volume) indicates platelet's thrombogenic activity. Overproduction or consumption of platelets in various cardiac conditions may affect MPV values. We aimed to investigate the pre and postprocedure MPV percentage change (MPV-PC) and its association with post-TAVR short-term complications. A total of 204 patients who underwent TAVR with a diagnosis of severe symptomatic AS were included. The mean age was 78.66 ± 6.45 years, and 49.5% of patients were women. Two groups generated according to composite end point (CEP) development: CEP(+) and CEP(-).110 patients(53.9%) formed CEP(+) group. Although baseline MPV and platelet levels were similar between groups, MPV was increased ( P  < 0.001) and platelet was decreased ( P  < 0.001) significantly following the procedure when compared to baseline. MPV-PC was significantly higher in the VARC type 2-4 bleeding ( P   =  0.036) and major vascular, access-related, or cardiac structural complication groups ( P   =  0.048) when CEP subgroups were analyzed individually. Regression analysis revealed that diabetes mellitus [ P   =  0.044, β: 1.806 odds ratio (95% confidence interval): 1.016-3.21] and MPV-PC [ P   =  0.007,β: 1.044 odds ratio (95% confidence interval): 1.012-1.077] as independent predictors of CEP development at 1 month after TAVR. The MPV increase following TAVR may be an indicator of adverse outcomes following TAVR procedure within 1-month.

Association between ambient air pollution exposure in pregnant women with antiphospholipid syndrome in Nanjing, China

Antenatal exposure to air pollutants is thought to be associated with a variety of maternal blood markers as well as adverse birth outcomes. However, the dysgenic influence of air pollutants on the antiphospholipid syndrome (APS) in mothers and their pregnancy outcomes remains unclear. In the current study, 371 mother-infant pairs (189 healthy: 182 APS) from Nanjing Maternal and Child Health Hospital as well as air pollutants concentration from their living environment were used to investigate correlations between air pollution with maternal blood indicators and fetal birth weight in the groups of APS and healthy mothers. Generalized linear model was used to evaluate the contributions of air pollutant exposure during pregnancy to the blood indicators variation. The relationships between birth weight with specific air pollutant and blood index were analyzed using ridge regression. Results showed that APS fetal birth weight was significantly impacted by air pollutant exposure during pregnancy, in particular, the birth weight decreased significantly along with increasing fine particulate matter 2.5 (PM2.5) and fine particulate matter 10 (PM10) exposure concentrations throughout pregnancy. In contrast, birth weight increased significantly with sulfur dioxide (SO2) exposure. In addition, APS-related blood indicators comprised of platelet distribution width (PDW), total bilirubin (TBIL), mean platelet volume (MPV), platelet-larger cell ratio (P_LCR), homocysteine (HCY), alkaline phosphatase (ALP), direct bilirubin (DBIL), basophilic granulocyte (BAS), platelet thrombocytocrit (PCT), preprandial glucose levels (OGTT0), monocytes (MON), and monocytes ratio (MON_ratio) were also strongly related with prenatal exposure to PM2.5 and PM10, in which PDW levels showed most strongly negative impaction on fetal birth weight. Together, we showed that prenatal exposure to air pollutant (PM2.5 and PM10) may exacerbate the poor birth outcomes of low birth weight by impacting APS maternal blood indicators especially for PDW.

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.

The Relationship Between TIMI Flow and MAPH Score in Patients Undergoing Primary Percutaneous Coronary Intervention for STEMI

The MAPH (mean platelet volume, age, total protein and hematocrit) score is a newly developed simple scoring system for patients with STEMI that has been associated with satisfactory predictive values to determine thrombus burden in STEMI patients. Therefore, the aim of our study was to determine the relationship between the MAPH risk score and TIMI flow in patients with STEMI.The study included 260 patients who underwent primary percutaneous coronary intervention between December 2019 to July 2022, and had TIMI 0 flow in the responsible coronary artery due to STEMI. According to the TIMI flow score after stent implantation, the patients were classified into either the no-reflow group (n = 59) or the normal flow group (n = 201). In order to calculate the MAPH score, ROC analysis was performed to find the cutoff point for each component of the MAPH score. MAPH scores were calculated (MPV + Age + Protein + Hematocrit) for both groups. Our study was a retrospective, observational study.In the multivariable regression analysis, the MAPH score (OR: 0.567; 95%CI: 0.330-0.973, P = 0.04) and glycoprotein IIb/IIIa inhibitors (OR: 0.249; 95%CI: 0.129-0.483, P < 0.001) were parameters found to be independent predictors of TIMI flow. An MAPH score value > 2.5 predicted the presence of low TIMI coronary flow in patients with STEMI, with 78% specificity and 45% sensitivity (ROC area under curve: 0.691, 95% CI: 0.617-0.766, P < 0.001).The MAPH risk score is simple, inexpensive, and quick to calculate. A high MAPH score may be an indicator of coronary no-reflow in patients with STEMI.

The Relationship of Plasma Aterogenity Index and Mean Platelet Volume with the Risk of Development of 1-Year Total Major Adverse Cardiac Event in Patients with Non-ST Elevation Myocardial Infarction

In our study, we aimed to reveal the role of plasma atherogenicity index and mean platelet volume in predicting the risk of developing a 1-year major adverse cardiac event (MACE) in patients with non-ST elevation myocardial infarction (NSTEMI). This study, which was planned from the retrospective cross-sectional study model, was performed with 100 patients diagnosed with NSTEMI and scheduled for coronary angiography. The laboratory values of the patients were evaluated, the atherogenicity index of plasma was calculated, and the 1-year MACE status was evaluated. In total, 79 of the patients were male and 21 were female. The average age is 60.8 years. At the end of the first year, the MACE improvement rate was found to be 29%. The PAI value was below 0.11 in 39% of the patients, between 0.11 and 0.21 in 14%, and above 0.21 in 47%. The 1-year MACE development rate was found to be significantly higher in diabetic patients and patients with hyperlipidemia. Lymphocyte count and triglyceride values of the patients in the high-risk group of atherogenic index of plasma (AIP) were found to be higher than the patients in the low-risk group. The neutrophil/lymphocyte, thrombocyte/lymphocyte ratios and high-density lipoprotein values of the patients in the high-risk group of AIP were found to be lower than those in the low-risk group. The rate of MACE development was found to be significantly higher in patients in the high-risk group of AIP ( p  = 0.02). No correlation was found between the mean platelet volume and the MACE development status. While no significant relationship was found between MPV and MACE in NSTEMI patients, AIP, which includes atherogenic parameters, was found to be correlated with MACE.

Antiplatelet effect of ginkgo diterpene lactone meglumine injection in acute ischemic stroke: A randomized, double-blind, placebo-controlled clinical trial

This study was designed to evaluate antiplatelet effect and therapeutic effect of ginkgo diterpene lactone meglumine injection (GDLI) in acute ischemic stroke (AIS) patients. In this randomized, double-blind, placebo-controlled trial, we randomly assigned 70 inpatients within 48 hr after the onset of AIS to combination therapy with GDLI and aspirin (GDLI at a dose of 25 mg/d for 14 days plus aspirin at a dose of 100 mg/d for 90 days) or to placebo plus aspirin in a ratio of 1:1. Platelet function, the National Institute of Health Stroke Scale (NIHSS), and the modified Rankin Scale (mRS) were evaluated. A good outcome was defined as NIHSS scores decrease ≥5 or mRS scores decrease ≥2. Results showed that arachidonic acid induced maximum platelet aggregation rate (AA-MAR) and mean platelet volume (MPV) of the GDLI-aspirin group were much lower than that of the aspirin group (p = 0.013 and p = 0.034, respectively) after the 14-day therapy. The combination of GDLI and aspirin was superior to aspirin alone, and had significant impact on the good outcome at day 90 (ORadj 7.21 [95%CI, 1.03-50.68], p = 0.047). In summary, GDLI has antiplatelet effect and can improve the prognosis of AIS patients.

Can mean platelet volume predicts renal outcome in acute on chronic kidney disease?

INTRODUCTION

This study aimed to investigate the role of mean platelet volume (MPV) in predicting renal outcome in acute kidney injury (AKI) developing on pre-existing chronic kidney disease (CKD).

METHODS

The patients whose first hemodialysis program was initiated in our center were divided into two groups as those who were taken to the scheduled dialysis program after discharge and those who were not dialysis-dependent. Groups were compared in terms of demographic characteristics, and laboratory parameters including MPV.

RESULTS

A total of 288 patients were included in the study (scheduled dialysis = 162 patients, nondialysis dependent = 126 patients). High MPV was found to be an independent risk factor for scheduled dialysis programs in multivariable analyses (OR [95% CI]: 90.9 [6.3-1313.6], p: 0.001).

CONCLUSION

CKD patients with high MPV were more likely to be included in scheduled dialysis programs after an AKI attack. MPV is found to be an independent risk factor and a reliable predictor for a scheduled dialysis program.

Diagnostic value of mean platelet volume combined with thromboelastography for coagulation state after total knee arthroplasty

BACKGROUND

The main objective of this study was to predict the status of blood and the occurrence of lower limb deep vein thrombosis (DVT) after total knee arthroplasty(TKA) by means of mean platelet volume (MPV) combined with thromboelastography (TEG).

METHODS

We collected 180 patients who underwent unilateral total knee arthroplasty between May 2015 and March 2022, and the patients were divided into DVT group and control group according to whole-leg ultrasonography on the seventh postoperative day. Blood count and TEG were performed on the day before surgery, the first day after surgery and the seventh day respectively. Multifactorial analysis was used to investigate whether the relevant parameters were independent predictors of DVT after TKA.

RESULTS

MPV has the strongest correlation with the maximum amplitude (MA), followed by alpha-angle; MPV and alpha-angle on the first postoperative day are independent predictors of DVT. MPV in patients with thrombosis tends to rise and then fall in the perioperative period. The optimal threshold for MPV to predict thrombosis is 10.85 fL and the area under the ROC curve is 0.694, The area under the ROC curve increases to 0.815 using MPV combined with alpha-angle. In addition, MA, α-angle, composite coagulation index (CI) and MPV were all statistically higher in the DVT group than in the control group (p < 0.001).

CONCLUSION

MPV is a predictor of DVT after TKA. It can reflect the hypercoagulable state of blood after surgery; Combination of MPV and alpha-angle on the first day after surgery in patients with TKA improves predictive power of DVT.

Association Between Platelet Indices and Preoperative Deep Vein Thrombosis in Elderly Patients Undergoing Total Joint Arthroplasty: A Retrospective Study

To investigate the association between platelet (PLT) indices and preoperative deep vein thrombosis (DVT) in elderly patients undergoing total joint arthroplasty (TJA). A total of 1391 patients were enrolled. We created receiver operator characteristic (ROC) curve using the ratio of PLT indices to DVT before TJA, divided the enrolled patients into groups based on the cut-off value, and then analyzed risk factors for DVT before TJA in the multivariate binary logistic regression analysis. Preoperative DVT occurred in 103 cases. Based on the ROC curve, we determined that the cut-off values for PLT, mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR), and plateletcrit (PCT) were 202 × 109/L, 11.4 fL, 13.2 fL, 34.6%, and 0.228%. And the areas under the curve were 0.606, 0.605, 0.617, 0.616, and 0.598. Multivariate binary regression analysis revealed that the risk of preoperative DVT in TJA patients with PLT≥202 × 109/L, MPV≤11.4 fL, PDW≤13.2 fL, P-LCR≤34.6%, and PCT≥0.228% increased by 2.32 (P < .001, 95% confidence interval [CI] [1.50-3.60]), 1.86 (P < .001, 95% CI [1.22-2.83]), 2.17 (P < .001, 95% CI [1.43-3.31]), 2.27 (P < .001, 95% CI [1.50-3.45]), and 1.76 times (P = .013, 95% CI [1.13-2.76]), respectively. Age, P < .001, odds ratio (OR) = 1.08, 95% CI [1.04-1.11]; corticosteroid use, P = .011, OR = 3.66, 95% CI [1.34-9.96]. We found that increased PLT count and PCT, decreased MPV, PDW, and P-LCR, old age, and corticosteroid use were independent risk factors for preoperative DVT in elderly TJA patients.

Atrial fibrillation and stroke

INTRODUCTION

Stroke is one of the leading causes of mortality and morbidity globally. Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is set to reach epidemic proportions. AF is associated with a five-fold increase in risk of stroke. Strokes caused by AF more often are fatal or result in severe disability. Even though the incidence of stroke has been significantly reduced by oral anticoagulation, AF is thought to account for a significant proportion of cryptogenic strokes where no etiology is identified.

AREAS COVERED

This article reviews the literature related to AF and stroke, pathophysiological insights, diagnosis of AF in stroke patients, and its management (Graphical Abstract).

EXPERT OPINION

The pathophysiology of thrombogenesis that links AF and stroke is not well understood and is an area of active research to identify new therapeutic targets to prevent AF and stroke. As the nature of AF and stroke is multifaceted, an integrated care approach to managing AF and stroke is increasingly essential.

Higher platelet count, even within normal range, is associated with increased arterial stiffness in young and middle-aged adults

Background: Platelet counts and mean platelet volume (MPV) are related to cardiovascular disease, but a thorough investigation into the connection between increased arterial stiffness, MPV, and platelet counts is lacking. This study aimed to explore the association of platelet count and MPV with arterial stiffness in young and middle-aged adults.

Methods: A total of 2464 participants who underwent health checkups at National Cheng Kung University Hospital, Taiwan from November 2018 to December 2019 were included. We excluded participants aged <18 or >50 years; who are pregnant; on medication for dyslipidemia; with abnormal platelet count, incomplete data, and past history of hematologic disorders. We examined the association of platelet counts and MPV values with brachial-ankle pulse wave velocity (baPWV) levels and increased arterial stiffness.

Results: Platelet count was significantly higher in participants with increased arterial stiffness than in those without. The multiple linear regression model revealed that platelet counts were positively associated with baPWV levels (β = 1.88, 95% confidence interval (CI): 0.96 to 2.80). In the binary logistic regression analysis, subjects in the higher platelet counts quartiles had a higher risk of developing increased arterial stiffness (Q2 vs. Q1: odds ratio (OR): 1.54, 95% CI: 1.05 to 2.27; Q3 vs. Q1: OR: 1.57, 95% CI: 1.06 to 2.33; and Q4 vs. Q1: OR: 2.23, 95% CI: 1.50 to 3.30). In contrast, MPV levels were not associated with arterial stiffness.

Conclusions: Platelet count in midlife was positively associated with baPWV levels. Participants in higher platelet quartiles were at risk for increased arterial stiffness.

A new marker of short-term mortality and poor outcome in patients with acute ischemic stroke: Mean platelet volume-to-lymphocyte ratio

BACKGROUND

The mean platelet volume-to-lymphocyte ratio (MPVLR), as a novel marker of thrombosis and inflammation, has been demonstrated to be closely linked to poor cardiovascular disease prognosis. However, the correlation between MPVLR and acute ischemic stroke (AIS) remains unclear. This study, therefore, aimed to clarify the relationship between MPVLR and the short-term prognosis of AIS.

METHODS

A total of 315 patients with first-time AIS diagnoses were recruited and divided into 3 groups based on the tri-sectional quantiles for MPVLR on admission: group 1 (N = 105) with a MPVLR ≤ 4.93, group 2 (N = 105) with a MPVLR of 4.94 to 7.21, and group 3 (N = 105) with a MPVLR ≥ 7.22. All patients were followed-up for 3 months, and death within 3 months was defined as the endpoint. Baseline characteristics, stroke severity, and functional outcomes were evaluated.

RESULTS

The Spearman's correlation coefficient test showed that MPVLR was significantly positively correlated with the National Institutes of Health Stroke Scale score (R = 0.517, P < .001). Multivariate analysis revealed that MPVLR was an independent predictor of both short-term mortality (adjusted odds ratio [OR] 1.435, P < .001) and poor outcome (adjusted OR 1.589, P < .001). The receiver operating characteristic (ROC) curve analysis showed that the best cutoff value of MPVLR for short-term mortality and poor outcome were 6.69 (sensitivity: 86.4%, specificity: 68.6%) and 6.38 (sensitivity: 78.8%, specificity: 72.3%), respectively.

CONCLUSIONS

MPVLR on admission was positively associated with stroke severity. An elevated MPVLR is an independent predictor of short-term mortality and poor outcome after AIS.

Diagnostic Accuracy of Platelet-Derived Parameters in Prognostication in Neurosurgery

Introduction. Platelets (PLT) are key mediators in thrombotic and inflammatory processes. Their activity increases with size, so the mean platelet volume (MPV) can be a potential predictor of perioperative complications. The aim of the study was to assess the suitability of platelet parameters in predicting the risk of hospital death in neurosurgery. Methods. Retrospective observation covered 452 patients undergoing surgery in the period March 2018−August 2018. High-risk patients accounted for 44% (i.e., ASA-PS class III+) and 9% (i.e., ≥1 Shoemaker criterion), respectively, and 14% of procedures were performed in the urgent mode. The preoperative platelet parameters that were assessed and analysed were: total platelet count (PLT), mean platelet volume (MPV), plateletcrit (PCT) and platelet distribution width (PDW). The end point of the study was a hospital death. Results. Before discharge from the hospital, 13 patients died. The medians (IQR) PLT, MPV PDW and PCT were, respectively: 230 × 106 L−1 (182−279); 9.2 fL (8.3−10.1); 14% (12.5−16.3); and 21% (17−26). PLT, PCT and PDW were not useful in the risk assessment. MPV was lower in patients who died (9.3 vs. 8.3 fL, p < 0.01) and predicted death occurred in 76% (AUC = 0.76, 95%CI 0.72−0.80, p < 0.01). Further, after adjustment for confounders, MPV remained a significant predictor of in-hospital death (logOR[MPV] = 0.31, AUC = 0.94, 95%CI 0.92−0.96, p = 0.02). Conclusion. The reduction in the average volume of platelets is associated with a worse prognosis in neurosurgical patients.

A New Score for Determining Thrombus Burden in STEMI Patients: The MAPH Score

Aim

to investigate whether the MAPH score, which is a new score that combines blood viscosity biomarkers such as mean platelet volume (MPV), total protein and hematocrit, can be used to predict thrombus burden in ST-segment elevation myocardial infarction (STEMI) patients.

Methods

A total of 473 consecutive patients with STEMI were included in the study. Intracoronary tirofiban/abciximab infusion was applied to patients with thrombus load ≥3 and these patients (n = 71) were defined as the patient group with high thrombus load. MPV, age, hematocrit and total protein values of the patients were recorded. High shear rate (HSR) and low shear rate (LSR) were calculated from total protein and hematocrit values. Cut-off values were determined for high thrombus load by using Youden index, and score was determined as 0 or 1 according to cut-offs. The sum of the scores was calculated as the MAPH score.

Results

The mean age of the patients included in the study was 59.6 ± 12.6 (n = 354 male, 74.8%). There was no difference between the groups in terms of gender, HT and DM (P = .127, P = .402 and P = .576, respectively). In the group with high thrombus load; total protein, MPV and hematocrit values were higher (P < .001, P = .001 and P = .03, respectively). Comparison of receiver operating characteristic (ROC) curve analysis revealed that the MAPH score had better performance in predicting higher thrombus load than both other self-containing parameters and HSR and LSR.

Conclusion

The MAPH score may be a new score that can be used to determine thrombus burden in STEMI patients.

Detection of Neanderthal Adaptively Introgressed Genetic Variants That Modulate Reporter Gene Expression in Human Immune Cells

Although some variation introgressed from Neanderthals has undergone selective sweeps, little is known about its functional significance. We used a Massively Parallel Reporter Assay (MPRA) to assay 5,353 high-frequency introgressed variants for their ability to modulate the gene expression within 170 bp of endogenous sequence. We identified 2,548 variants in active putative cis-regulatory elements (CREs) and 292 expression-modulating variants (emVars). These emVars are predicted to alter the binding motifs of important immune transcription factors, are enriched for associations with neutrophil and white blood cell count, and are associated with the expression of genes that function in innate immune pathways including inflammatory response and antiviral defense. We combined the MPRA data with other data sets to identify strong candidates to be driver variants of positive selection including an emVar that may contribute to protection against severe COVID-19 response. We endogenously deleted two CREs containing expression-modulation variants linked to immune function, rs11624425 and rs80317430, identifying their primary genic targets as ELMSAN1, and PAN2 and STAT2, respectively, three genes differentially expressed during influenza infection. Overall, we present the first database of experimentally identified expression-modulating Neanderthal-introgressed alleles contributing to potential immune response in modern humans.

Is there a relationship between renal scarring and neutrophil-to-lymphocyte ratio in patients with vesicoureteral reflux?

OBJECTIVES

Vesicoureteral reflux (VUR) exacerbates the risk of renal scarring by establishing a ground for pyelonephritis. It is known that the inflammatory process is more influential than the direct damage caused by bacterial infection in the development of renal scars after pyelonephritis. Therefore, the present study aims to investigate the relationship between renal scarring and systemic inflammatory markers in patients with VUR.

MATERIAL AND METHODS

Hundred and ninety-two patients (116 females, 76 males) diagnosed with VUR were divided into two groups based on the presence or absence of renal scarring and into three groups according to the grade of VUR (low, moderate and high). Neutrophil count, lymphocyte count, mean platelet volume (MPV) and neutrophil-to-lymphocyte ratio (NLR) were compared among the groups.

RESULTS

Of the 192 patients, 102 had renal scarring. The age and gender distribution did not differ significantly between the groups with and without renal scarring (p > 0.05). However, the grade of reflux and lymphocyte count were significantly higher in the group with renal scarring (p < 0.05), and the NLR was significantly lower in the group with renal scarring (p < 0.05). The lymphocyte count was significantly higher (p < 0.05) and NLR was significantly lower in the high-grade VUR group (p < 0.05). However, MPV values did not differ significantly (p > 0.05) between the groups.

CONCLUSIONS

NLR can be used to predict renal scarring in patients with VUR, especially in the period of 3-6 months after the first attack of infection, and may even serve as a candidate marker for treatment selection. However, larger series and prospective studies are needed.

Remediation of ABCG5-Linked Macrothrombocytopenia With Ezetimibe Therapy

To investigate refractory hypercholesterolemia, a female patient and relatives were subjected to whole-genome sequencing. The proband was found to have compound heterozygous substitutions p. Arg446Gln and c.1118+3G>T in ABCG5, one of two genes causing sitosterolemia. When tracing these variants in the full pedigree, all maternally related heterozygotes for the intronic ABCG5 variant exhibited large platelets (over 30 fl), which segregated in an autosomal dominant manner, consistent with macrothrombocytopenia, or large platelet syndrome which may be associated with a bleeding tendency. In vitro cell-line and in vivo rat model experiments supported a pathogenic role for the variant and the macrothrombocytopenia was recapitulated in heterozygous rats and human cell lines exhibiting that single variant. Ezetimibe treatment successfully ameliorated all the symptoms of the proband with sitosterolemia and resolved the macrothrombocytopenia of the treated heterozygote relatives. Subsequently, in follow up these observations, platelet size, and size distribution were measured in 1,180 individuals; 30 were found to be clinically abnormal, three of which carried a single known pathogenic ABCG5 variant (p.Arg446Ter) and two individuals carried novel ABCG5 variants of uncertain significance. In this study, we discovered that identification of large platelets and therefore a possible macrothrombocytopenia diagnosis could easily be inadvertently missed in clinical practice due to variable instrument settings. These findings suggest that ABCG5 heterozygosity may cause macrothrombocytopenia, that Ezetimibe treatment may resolve macrothrombocytopenia in such individuals, and that increased attention to platelet size on complete blood counts can aid in the identification of candidates for ABCG5 genetic testing who might benefit from Ezetimibe treatment.

Evaluation of Platelet Indices in Patients with Splanchnic Vein Thrombosis

Splanchnic vein thrombosis (SVT) is a rare and lethal form of venous thrombosis. The role of platelet indices (PI's) is not well studied in SVT. The present study was aimed to assess if the PI's have a significant association with SVT. This was a prospective case control study from coagulation laboratory of Hematology department. A total 100 cases of SVT and 80 controls were screened for PI's (MPV, PCT & PDW) and platelet count (PC) along with routine thrombophilic risk factors. The SVT cases were divided into 3 subgroups, that comprised of EHPVO/ PVT (n = 69), BCS (n = 27), and MVT (n = 4). The mean PC and PCT were significantly lower in patients than the controls. The PDW was significantly higher in cases than in the controls and MPV was relatively higher in cases however did not show statistical significance. In addition, 16 patients were found to have deranged thrombophilic risk factors. Among these, 8 cases had inherited risk factors (2: FVL; 5: PC; 1: PS) and 8 cases had acquired risk factors (2: APL; and 5: multiple factors and one case had both FVL mutation and APL positivity). The PDW and PCT together with PC were found to significantly differ in SVT cases than in controls, particularly in idiopathic cases. It may be worthwhile to explore the utility of PI's as a potential risk factor in SVT.

Supplementary Information

The online version contains supplementary material available at (10.1007/s12288-021-01400-5).

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.

Platelet and Thrombophilia-Related Risk Factors of Retinal Vein Occlusion

Retinal vein occlusion (RVO) is a heterogenous disorder in which the formation of a thrombus results in the retinal venous system narrowing and obstructing venous return from the retinal circulation. The pathogenesis of RVO remains uncertain, but it is believed to be multifactorial and to depend on both local and systemic factors, which can be divided into vascular, platelet, and hypercoagulable factors. The vascular factors include dyslipidaemia, high blood pressure, and diabetes mellitus. Regarding the platelet factors, platelet function, mean platelet volume (MPV), platelet distribution width (PDW), and platelet large cell ratio (PLCR) play key roles in the diagnosis of retinal vein occlusion and should be monitored. Nevertheless, the role of a hypercoagulable state in retinal vein occlusion remains unclear and requires further studies. Therefore, the following article will present the risk factors of RVO associated with coagulation disorders, as well as the acquired and genetic risk factors of thrombophilia. According to Virchow’s triad, all factors mentioned above lead to thrombus formation, which causes pathophysiological changes inside venous vessels in the fundus of the eye, which in turn results in the vessel occlusion. Therefore, a diagnosis of retinal vein occlusion should be based on both eye examination and general examination, including laboratory tests.

Mean Platelet Volume as a Potential Marker of Large Vessel Occlusion and Predictor of Outcome in Acute Ischemic Stroke Patients Treated with Reperfusion Therapy

(1) Background: An early diagnosis of a large vessel occlusion (LVO) is crucial in the management of the acute ischemic stroke (AIS). The laboratory predictors of LVO and a stroke outcome remain unknown. We have hypothesized that high MPV—a surrogate marker of the activated platelet—may be associated with LVO, and it may predict a worse AIS outcome. (2) Methods: This was a retrospective study of 361 patients with AIS who were treated with thrombolysis (tPA, 65.7%) and/or mechanical thrombectomy (MT, 34.3%) in a tertiary Stroke Center between 2011 and 2019. (3) Results: The mean MPV in the cohort was 9.86 ± 1.5 fL (1st–4th quartiles: <8.8, >10.80 fL). Patients in the 4th quartile compared to the 1st had a significantly (p < 0.01) more often incidence of an LVO related stroke (75% vs. 39%) and a severe stroke manifestation with a higher RACE score (5.2 ± 2.8 vs. 3.3 ± 2.4), NIHSS at baseline (mean ± SD, 14 ± 6.5 vs. 10.9 ± 5.2), and NIHSS at discharge (6.9 ± 7 vs. 3.9 ± 3.6). A multivariate analysis revealed that quartiles of MPV (OR 1.4; 95%CI 1.2–1.8) significantly predicted an LVO stroke, also after the adjustment for RACE < 5 (OR 1.4; 95%CI 1.08–1.89), but MPV quartiles did not predict a favorable stroke outcome (mRS ≤ 2) (OR 0.89; 95%CI 0.7–1.13). (4) Conclusion: Our data suggest that MPV is an independent predictor of LVO in patients with an acute ischemic stroke.

No obvious association exists between mean platelet volume and hypertension subtypes

Aims: To determine the association between mean platelet volume (MPV) and hypertension subtypes. Participants & results: 44,281 Chinese individuals were enrolled in this cross-sectional study. The mean blood pressure decreased with increasing MPV in females (p = 0.001) and increased MPV seemed to be a potential protective factor for isolated diastolic hypertension in models 1 and 2. The OR (CI) was 0.878 (0.789-0.976) for model 1 and 0.880 (0.789-0.981) for model 2 in males and 0.646 (0.495-0.841) for model 1 and 0.657 (0.503-0.858) for model 2 in females, when MPV was analyzed as a categorical variable. The OR (CI) was 0.947 (0.911-0.985) for Model 1 and 0.947 (0.910-0.985) for Model 2 in males, and 0.886 (0.807-0.973) for Model 1 and 0.892 (0.813-0.978) for Model 2 in females when MPV was analyzed as a continuous variable. However, the statistical difference of OR disappeared when we added blood-related covariates in Model 3. Conclusion: No obvious association exists between MPV and hypertension subtypes. Other blood parameters might have a greater impact on hypertension subtypes.

Associations of platelet indices with proteinuria and chronic kidney disease

OBJECTIVES

Platelet (PLT) indices are predictive in many diseases and conditions. The relationships of these indices with proteinuria and progression of renal disease are not well known. This study aimed to assess PLT indices in patients with primary glomerular nephrotic range proteinuria (PGNRP), with and without chronic kidney disease (CKD), and to compare these indices with those of healthy individuals (His).

METHODS

This cross-sectional study was performed from January 2015 to May 2015. HIs (n = 57) and patients with PGNRP (n = 41) were enrolled. PLT indices and blood biochemistry parameters were compared between HIs and patients with PGNRP, as well as between subgroups of patients with PGNRP who had CKD (n = 23) and those who did not have CKD (n = 18).

RESULTS

There were no statistically significant differences in any PLT indices (i.e., platelet number, mean platelet volume, plateletcrit, and platelet distribution width) between HIs and patients with PGNRP, or between the subgroups of patients with PGNRP. However, patients with PGNRP who had CKD exhibited higher median C-reactive protein and mean albumin levels, compared with patients who did not have CKD.

CONCLUSIONS

Pathological processes in proteinuria and CKD are not associated with PLT indices.

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.

Impact of gender on immature platelet count and its relationship with coronary artery disease

The impact of platelet parameters on the cardiovascular risk is still debated. Gender differences in platelet volume indexes and turnover have been previously reported, potentially conditioning their role in the development of coronary artery disease (CAD). However, few studies have addressed, so far, the impact of gender on the immature platelet fraction (IPF) and count (IPC) and their relationship with CAD. We enrolled consecutive patients undergoing coronary angiography in a single centre. IPF and platelet indexes were measured at admission. Significant CAD was defined as the presence of at least one coronary stenosis more than 50%. A total of 2550 patients were included, 1835 (72%) were males, and 715 (28%) were females. Female patients were older (p < 0.001), with lower BMI (p = 0.002), lower prevalence of active smoking (p < 0.001), previous MI, previous PCI and CABG (p = 0.001, p = 0.001, p < 0.001), whilst a higher prevalence of renal failure (p = 0.02), acute presentation (p < 0.001) and CAD (p < 0.001). Platelet count was higher in females (p < 0.001), as well as the IPC levels (838.38 ± 562.05 vs 792.24 ± 535.66, p = 0.05) with no difference in the levels of immature platelet fraction (3.67 ± 2.68% vs 3.74 ± 2.6%, p = 0.55) or the prevalence of patients with IPF ≥ 3rd tertile (33.7% vs 35.2%, p = 0.26). At multivariate analysis, after correction for baseline confounders, gender did not emerge as an independent predictor of higher IPF (adjusted OR [95% CI] = 0.82 [0.64-1.06], p = 0.13). When dividing our patients according to the levels of IPF, in women we observed an inverse association between IPF ≥ 3rd tertile and coronary calcifications (p = 0.025) and a higher prevalence of restenosis (p = 0.003), but no difference in CAD (65.6% vs 66.9%, p = 0.71) or severe CAD (28.1% vs 24.7%, p = 0.31). In males, the IPF ≥ 3rd tertile related with a lower TIMI flow (p = 0.001). Males with lower IPF had a significantly higher percentage of CAD (87.7% vs 83.3%, p = 0.007; adjusted OR: 0.699 [95% CI] = [0.54-0.91], p = 0.008) but not for severe CAD (36.5% vs 39.9%, p = 0.134). The present study shows that among patients undergoing coronary angiography, gender is not associated to the levels of immature platelet fraction. Moreover, we found no association between IPF and the prevalence and extent of CAD in female gender, whereas in male gender the IPF was inversely related with the prevalence of CAD.

Association of inflammatory and platelet volume markers with clinical outcome in patients with anterior circulation ischaemic stroke after endovascular thrombectomy

Background: To determine the correlation of inflammatory and platelet volume indices with the severity of stroke and 3-month clinical outcomes in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT).Methods: A retrospective analysis was conducted for AIS patients who underwent EVT at our hospital from 2015 to 2019. Inflammatory factors, including white blood count, neutrophil count, lymphocyte count, neutrophil to lymphocyte ratio (NLR), high-sensitivity C-reactive protein (hs-CRP), procalcitonin (PCT) and interleukin-6 (IL-6), and platelet volume indices, including platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW) and MPV/PC levels were assessed. Results were analyzed between patients with favorable and unfavorable outcomes at 3 months post-EVT.Results: A total of 257 AIS patients were included in the study. There were 86 (33.5%) patients with favorable functional outcomes at 3 months. Compared to patients with favorable outcomes, those with poor outcomes have lower lymphocyte count, higher neutrophil count and NLR levels. There were no differences in hs-CRP,PCT and IL-6 between the two groups. The correlation analysis showed that the increase in MPV, PDW, and MPV/PC was related to the high level of the NIHSS score at admission. Multivariate logistic regression analysis showed that higher NLR levels are an independent risk factor for unfavorable outcomes at 3 months (OR = 1.141; 95% CI 1.061 to 1.227, P = 0.000).Conclusions: MPV, PDW, and MPV/PC are associated with stroke severity. Higher NLR levels upon admission may predict unfavorable functional outcomes in patients with AIS after undergoing EVT.Abbreviations ACA: anterior cerebral artery; AIS: acute ischemic stroke; ASPECTS: alberta stroke program early CT score; BMI: body mass index; DBP: diastolic blood pressure; END: early neurological deterioration; EVT: endovascular thrombectomy; hs-CRP: high-sensitivity C-reactive protein; HT: hemorrhagic transformation; ICA: internal carotid artery; IL-6: interleukin-6; IS: ischemic progression; LAA: Large-Artery Atherosclerosis; MCA: middle cerebral artery; MPV: mean platelet volume; mTICI: modified thrombolysis in cerebral infarction; NIHSS: National Institute of Health stroke scale; NLR: neutrophil to lymphocyte ratio; OTP: onset-to-puncture; PC: platelet count; PCT: procalcitonin; PDW: platelet distribution width; SBP: systolic blood pressure; sICH: symptomatic intracerebral hemorrhageWBC: white blood cell.

The relationship between erectile dysfunction severity, mean platelet volume and vitamin D levels

Background: The aim of this study was to evaluate the relationship between mean platelet volume (MPV) and vitamin D levels according to ED severity.Methods: Between October 2015 and September 2017, patients who applied to the andrology outpatient clinic with an ED complaint were retrospectively reviewed. Patients with diabetes, hypertension, hyperlipidemia, malignancy, late-onset hypogonadism and smokers were not included in the study. The International Erectile Function Index-Erectile Function (IIEF-EF) questionnaire was used to assess the levels of erectile function. According to this scoring system, patients were divided into two groups. IIEF score: between 17 and 25 = mild ED (Group 1) and IIEF score between 16 and 0 = moderate-severe ED (Group 2). Blood samples of the patients were taken from antecubital vein and MPV and 25-hydroxyvitamin D [25(OH)D] levels were evaluated.Results: Ninety patients were included in the study (Group 1: n = 41, Group 2: n = 49). The mean age of the patients was 41.07 ± 8.56 and the mean body mass index (BMI) was 27.59 ± 3.91. 25(OH)D levels were found to be statistically lower in Group 2 (18.85 ± 6.09; 13.98 ± 7.10; p = .001). MPV levels were found to be statistically higher in Group 2 (10.05 ± 0.81; 10.78 ± 1.16; p = .001). Correlation between IIEF-EF scores and 25(OH)D levels was positive (p = .03, r = 0.22). There was negative correlation between IIEF-EF scores and MPV and between 25(OH)D levels and MPV levels [p = .003 for IIEF-EF/MPV, p = .04, r = -0.23 for 25(OH)D/MPV].Conclusion: There is a significant positive correlation between ED severity and 25(OH)D levels and there is a significant negative correlation between ED severity and MPV levels.

Role of the Platelets and Nitric Oxide Biotransformation in Ischemic Stroke: A Translative Review from Bench to Bedside

Ischemic stroke remains the fifth cause of death, as reported worldwide annually. Endothelial dysfunction (ED) manifesting with lower nitric oxide (NO) bioavailability leads to increased vascular tone, inflammation, and platelet activation and remains among the major contributors to cardiovascular diseases (CVD). Moreover, temporal fluctuations in the NO bioavailability during ischemic stroke point to its key role in the cerebral blood flow (CBF) regulation, and some data suggest that they may be responsible for the maintenance of CBF within the ischemic penumbra in order to reduce infarct size. Several years ago, the inhibitory role of the platelet NO production on a thrombus formation has been discovered, which initiated the era of extensive studies on the platelet-derived nitric oxide (PDNO) as a platelet negative feedback regulator. Very recently, Radziwon-Balicka et al. discovered two subpopulations of human platelets, based on the expression of the endothelial nitric oxide synthase (eNOS-positive or eNOS-negative platelets, respectively). The e-NOS-negative ones fail to produce NO, which attenuates their cyclic guanosine monophosphate (cGMP) signaling pathway and-as result-promotes adhesion and aggregation while the e-NOS-positive ones limit thrombus formation. Asymmetric dimethylarginine (ADMA), a competitive NOS inhibitor, is an independent cardiovascular risk factor, and its expression alongside with the enzymes responsible for its synthesis and degradation was recently shown also in platelets. Overproduction of ADMA in this compartment may increase platelet activation and cause endothelial damage, additionally to that induced by its plasma pool. All the recent discoveries of diverse eNOS expression in platelets and its role in regulation of thrombus formation together with studies on the NOS inhibitors have opened a new chapter in translational medicine investigating the onset of acute cardiovascular events of ischemic origin. This translative review briefly summarizes the role of platelets and NO biotransformation in the pathogenesis and clinical course of ischemic stroke.

Mean Platelet Volume as a Marker of Vasculogenic Erectile Dysfunction and Future Cardiovascular Risk

Cardiovascular diseases are the main cause of mortality in the Western population, so the attempt to find a marker capable of predicting their early onset is not surprising. It is known that arteriogenic erectile dysfunction (ED) precedes the onset of a major coronary event by several years. However, a marker that is able to early identify those patients who should undergo further diagnostic investigations is, to date, missing. Recent research on this topic has focused on the role of the mean platelet volume (MPV), a marker of platelet activity that is high in most vascular diseases, such as coronary artery disease (CAD), stroke, peripheral artery disease (PAD), and ED. The basic pathophysiological mechanism of all these clinical conditions is atherosclerosis. Platelets play a central role in amplifying this process both indirectly by stimulating endothelial cells to produce inflammatory cytokines and chemokines, and directly through the expression of membrane receptors and the release of molecules that contribute to the formation of atherosclerotic plaque. The objective of this review is to critically analyze the evidence on the role of MPV in predicting the diagnosis and severity of vasculogenic ED and the possibility of using this simple marker as a first step to start a diagnostic process aimed at assessing the cardiovascular risk in these patients.

Evaluation of Biomarkers for the Prediction of Venous Thromboembolism in Ambulatory Cancer Patients

BACKGROUND

Venous thromboembolism (VTE) is a common complication of cancer. This study aimed to evaluate immature platelet fraction (IPF), mean platelet volume (MPV), P-selectin, D-dimer, and thrombin generation (TG) as predictive biomarkers for VTE and further the improvement of existing risk assessment models (RAMs).

METHODS

A prospective, observational, exploratory study was conducted on ambulatory cancer patients with indication for systemic chemotherapy. Baseline RAMs included the Khorana-, Vienna Cancer, Thrombosis-, Protecht-, ONKOTEV-, and Catscore. IPF, MPV, P-selectin, D-dimer, and TG were analysed at baseline and 3-month follow-up.

RESULTS

We enrolled 100 patients, of whom 89 completed the follow-up. Frequent tumour types were breast (30%), gastric (14%), gynaecological (14%), and colorectal (14%) cancer. Ten of the 89 patients (11.2%) developed VTE. The highest VTE rate was observed in patients with cholangiocarcinoma (3/5; 60%). Baseline D-dimer levels but not IPF, MPV, or P-selectin were associated with the risk of developing VTE (HR 6.9; p = 0.021). None of the RAMs showed statistical significance in predicting VTE. Peak thrombin and endogenous thrombin potential were lower in patients who developed VTE. Biomarker changes between baseline and follow-up were not associated with VTE risk.

CONCLUSIONS

VTE risk was well predicted by baseline D-dimer levels. Adding D-dimer could improve existing RAMs to better identify patients who may benefit from primary VTE prophylaxis. The VTE risk among patients with cholangiocarcinoma should be further evaluated.

Mean platelet volume and its genetic variants relate to stroke severity and 1-year mortality

OBJECTIVE

To determine whether mean platelet volume (MPV) and selected single nucleotide polymorphisms (SNPs) that have been associated with MPV in genome-wide association studies relate to stroke severity, functional outcome on discharge, and 1-year mortality in patients with ischemic stroke, we retrospectively analyzed 577 patients with first-ever ischemic stroke.

METHODS

Genotyping of 3 SNPs (rs342293, rs1354034, rs7961894) was performed using a real-time PCR allelic discrimination assay. Multivariable regression was used to determine the association of MPV and MPV-associated SNPs with the NIH Stroke Scale (NIHSS) score on admission, modified Rankin Scale score on discharge, and data on 1-year mortality.

RESULTS

Rs7961894, but not rs342293 or rs1354034 SNP, was independently associated with an MPV in the highest quartile (MPV Q4). MPV Q4 was associated with significantly greater admission NIHSS (p = 0.006), poor discharge outcome (p = 0.034), and worse 1-year mortality (p = 0.033). After adjustment for pertinent covariates, MPV Q4 remained independently associated with a greater admission NIHSS score (p = 0.025). The T>C variant of rs7961894 SNP was an independent marker of a lower 1-year mortality (hazard ratio, 0.30; 95% confidence interval, 0.13-0.70; p = 0.006) in the studied population.

CONCLUSION

MPV is a marker of stroke severity and T>C variant of rs7961894 is independently associated with greater MPV in acute phase of ischemic stroke and relates to decreased 1-year mortality after stroke.

Mean platelet volume and coronary artery disease

PURPOSE OF REVIEW

To critically review the literature describing links between mean platelet volume (MPV) and cardiovascular disease (CVD). We will focus on coronary artery disease (CAD). The MPV is measured routinely as part of a routine blood count.

RECENT FINDINGS

There is accumulating evidence showing that the MPV may predict CVD, as well as outcomes in patients with CAD. There is also evidence linking MPV and comorbidities (e.g. diabetes mellitus and impaired glycaemic control) that are expected in patients with CAD. The effect on MPV of drugs commonly used to treat CAD has not been clarified, but there is some evidence that they may exert a beneficial effect on the MPV. More specifically, the MPV may predict the effect of antiplatelet drugs (e.g. clopidogrel). There is also evidence relating MPV to stroke, atrial fibrillation, coronary artery ectasia and periprocedural outcomes after percutaneous coronary intervention (PCI).

SUMMARY

Measuring the MPV may prove useful in CVD risk assessment in patients with established CAD or at risk of developing CAD. Overall, there is evidence pointing to the role of MPV as a contributor rather than simple marker of CVD.

The molecular basis of platelet biogenesis, activation, aggregation and implications in neurological disorders

Platelets are anucleated blood constituents, vital for hemostasis and involved in the pathophysiology of several cardiovascular, neurovascular diseases as well as inflammatory processes and metastasis. Over the past few years, the molecular processes that regulate the function of platelets in hemostasis and thrombosis have emerged revealing platelets to be perhaps more complex than may have been expected. The most understood part of platelets is to respond to a blood vessel injury by altering shape, secreting granule contents, and aggregating. These responses, while advantageous for hemostasis, can become detrimental when they root ischemia or infarction. Only a few transcription and signaling factors involved in platelet biogenesis have been identified till date. Platelets encompass an astonishingly complete array of organelles and storage granules including mitochondria, lysosomes, alpha granules, dense granules, a dense tubular system (analogous to the endoplasmic reticulum of nucleated cells); a highly invaginated plasma membrane system known as the open canalicular system (OCS) and large fields of glycogen. Platelets as a model cells to study neurological disorders have been recommended by several researchers since several counterparts exist between platelets and the brain, which make them interesting for studying the neurobiology of various neurological disorders. This review has been compiled with an aim to integrate the latest research on platelet biogenesis, activation and aggregation focusing on the molecular pathways that power and regulate these processes. The dysregulation of important molecular players affecting fluctuating platelet biology and thereby resulting in neurovascular diseases has also been discussed.

Association Between Mean Platelet Volume and Hemorrhagic Transformation in Acute Ischemic Stroke Patients

BACKGROUND

Hemorrhagic transformation (HT) is a frequent complication of acute ischemic stroke (AIS). Mean platelet volume (MPV) is a marker of platelet function. The relationship between MPV and HT remains unclear.

METHODS

From January 1st, 2012 to December 31st 2016, we consecutively enrolled AIS patients admitted to the Department of Neurology of West China Hospital. MPV was measured on admission. HT was diagnosed by brain imaging and classified into hemorrhagic infarct (HI) and parenchymal hematoma (PH). Moreover, subjects were divided into tertiles according to MPV levels. Confounders were identified by univariate analysis and multivariate logistic regression was performed to explore the association between MPV and HT as well as HT subtypes. Also, a generalized additive model was used to investigate whether a non-linear association existed between MPV and HT.

RESULTS

A total of 783 AIS patients were included. 63 patients (8.0%) developed HT: 34 (4.3%) HI and 29 (3.7%) PH. It was observed that MPV positively correlated with HT. After adjustment for confounders, patients in the highest MPV tertile had a significantly increased risk of HT compared to patients in the lowest tertile (odds ratio 2.3, 95% confidence interval 1.0-5.4, P=0.04). The risk of HT increased step-wise across MPV tertiles (P for trend=0.04). MPV tertiles significantly correlated with HI rather than PH. The generalized additive model demonstrated a nonlinear association between MPV and HT (P=0.02).

CONCLUSION

The risk of HT increased with increasing MPV level in a dose-dependent manner. Patients with elevated MPV levels were more likely to develop HI rather than PH.

Effect of new oral anticoagulants on platelet indices in non-valvular atrial fibrillation patients

New-generation oral anticoagulants (NOACs) are now preferred as a first-line treatment in the management of atrial fibrillation for prevention of thromboembolic complications. Mean platelet volume (MPV), one of the indicators of increased platelet activity, is also associated with an increased stroke risk in atrial fibrillation patients. The aim of this study was to evaluate changes in MPV, platelet distribution width (PDW) and plateletcrit following use of NOACs. The study included 116 patients with non-valvular atrial fibrillation without previous NOAC use. Complete blood counts, biochemical analyses and echocardiography were performed for all patients. No significant differences were observed in MPV or other platelet indices at 6 months compared to baseline. Our results indicate that MPV and other platelet indices are not affected by NOAC use in non-valvular atrial fibrillation patients.

Evaluation of the Potential Association of Platelet Levels, Mean Platelet Volume and Platelet Distribution Width with Acute Appendicitis

BACKGROUND:

The occurrence and early management of acute appendicitis among children are especially important due to the difficult diagnosis and nonspecific symptoms of the disease. Diagnosis of appendicitis in children is very difficult due to similarity of its symptoms to other diseases, and also its self-limiting nature Platelet indexes such as mean platelet volume (MPV) and platelet distribution width (PDW) have been suggested as a biomarker of inflammation.

AIM:

Therefore, we examined the association of MPV and PDW with acute appendicitis in children.

METHODS:

This cross-sectional study was conducted on 464 patients with suspected acute appendicitis under the age of 18 years referred to the specialised hospitals of the ten studied provinces between October 2014 and October 2015. All data obtained regarding patient’s lab tests, i.e. platelet count, MPV and PDW and also radiological studies and surgical reports were gathered in datasheets and analysed to evaluate the potential association of platelet levels, mean platelet volume (MPV) and platelet distribution width (PDW) with acute appendicitis

RESULTS:

Our results showed that the MPV was significantly higher in acute appendicitis in comparison to perforated appendicitis as well as acute gangrenous appendicitis. PDW was significantly higher in acute appendicitis in comparison to perforated appendicitis and acute gangrenous appendicitis. The current project indicated that PDW < 10.05 had a sensitivity of 35% and specificity of 75%, platelet count < 229500 had a sensitivity of 24% and specificity of 75% and MPV < 8.95 had a sensitivity of 70% and specificity of 71%.

CONCLUSION:

Our study suggested that platelet indexes such as MPV and PDW could significantly correlate with acute appendicitis in pediatric patients. Hence, we believe that both MPV and PDW could use as a simple and low-cost lab test for diagnosing acute appendicitis. Also, this study revealed that the MPV lower than 8.95 could be a novel index for diagnosing acute appendicitis with sensitivity of 70% and specificity of 71%.

Assessment of Mean Platelet Volume in Patients with AA Amyloidosis and AA Amyloidosis Secondary to Familial Mediterranean Fever: A Retrospective Chart - Review Study

Background

Amyloidosis is a protein-misfolding disease characterized by the deposition of aggregated proteins in the form of abnormal fibrils that disrupt tissue structure, ultimately causing disease. Amyloidosis is very frequent in untreated familial Mediterranean fever (FMF) patients and it is the most important feature that determines the prognosis of FMF disease. The mean platelet volume (MPV) in FMF has been previously studied. However, whether MPV level in FMF patients is lower or higher compared to healthy controls remains a topic of ongoing debate. In this study, we aimed to investigate MPV values and to assess the correlation between MPV and proteinuria in patients with AA amyloidosis and AA amyloidosis secondary to familial Mediterranean fever (AA-FMF) through a retrospective chart-review.

Material/Methods

This study was carried out on 27 patients with AA amyloidosis, 36 patients with AA amyloidosis secondary to FMF (a total of 63 patients with AA), and 29 healthy controls. There was no statistically significant difference between the AA patients and the control group (p=0.06) or between the AA-FMF group and the control group in terms of MPV values (p=0.12).

Results

We found a statistically significant negative correlation between MPV and thrombocyte count in all groups (p<0.05 for all groups), but there was no correlation between MPV and proteinuria levels in AA patients (p=0.091).

Conclusions

While similar results also exist, these findings are contrary to the majority of previous studies. Therefore, further controlled clinical prospective trials are necessary to address this inconsistency.

Mean platelet volume and clinical outcomes of patients with chest pain discharged from internal medicine wards

BACKGROUND

Currently, there are no clinical scores for risk stratification of low-risk patients with chest pain. We aimed to examine the association between mean platelet volume (MPV) and risk for adverse clinical outcomes in patients with chest pain discharged from internal medicine wards following acute coronary syndrome (ACS) rule-out.

PATIENTS AND METHODS

Included were patients who were admitted to internal medicine wards and were discharged following an ACS-rule-out during 2010-2016. The primary endpoint was the composite of all-cause mortality and hospital admission due to ACS at 30-days following hospital discharge.

RESULTS

Included in the study were12 440 patients who were divided into three groups according to MPV. The composite endpoint of 30-day all-cause mortality and hospital admission for ACS occurred more frequently among patients with high MPV. Each one-point increase in MPV was associated with an 18% increase in the risk for the composite endpoint (P = 0.02). Considering patients with MPV less than 7.8 fl as the reference group yielded adjusted hazard ratios for the composite endpoint that was significantly higher in patients in the high MPV tertile ( > 8.8 fl) (hazard ratio 1.6; 95% confidence interval = 1.1-2.5; P = 0.04). Each one-point increase in MPV was associated with an 11% increase in the risk for 1-year all-cause mortality (P = 0.01) and a 10% increase in the risk for 1-year ACS (P = 0.04).

CONCLUSION

We found an independent association between high MPV and the risk of death and ACS among patients with chest pain who were discharged from internal medicine wards following an ACS-rule-out. MPV may be combined in the risk stratification of patients with chest pain.