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Critical Care (London, England) Aug 2018Platelets (PLTs) are usually stored for up to 5 days prior to transfusion, although in some blood services the storage period is extended to 7 days. During storage,...
BACKGROUND
Platelets (PLTs) are usually stored for up to 5 days prior to transfusion, although in some blood services the storage period is extended to 7 days. During storage, changes occur in both PLT and storage medium, which may lead to PLT activation and dysfunction. The clinical significance of these changes remains uncertain.
METHODS
We performed a systematic review to assess the association between PLT storage time and clinical or transfusion outcomes in patients receiving allogeneic PLT transfusion. We searched studies published in English between January 2000 and July 2017 identified from MEDLINE, Embase, PubMed and the Cochrane Libraries.
RESULTS
Of the 18 studies identified, five included 4719 critically ill patients (trauma, post-cardiac surgery and a heterogeneous population of critically ill patients) and 13 included 8569 haematology patients. The five studies in critically ill patients were retrospective and did not find any association between PLT storage time when PLTs were stored for up to 5 days and mortality. There was also no association between older PLTs and sepsis in the two largest studies (n = 4008 patients). Of the 13 studies in haematology patients, seven analysed prolonged storage time up to 6.5 or 7 days. Administration of fresh PLTs (less than 2 or 3 days) was associated with a significant increase in corrected count increment (CCI) compared to older PLTs in seven of the eight studies analysing this outcome. One single centre retrospective study found an increase in bleeding events in patients receiving older PLTs.
CONCLUSIONS
PLT storage time does not appear to be associated with clinical outcomes, including bleeding, sepsis or mortality, in critically ill patients or haematology patients. The freshest PLTs (less than 3 days) were associated with a better CCI, although there was no impact on bleeding events, questioning the clinical significance of this association. However, there is an absence of evidence to draw definitive conclusions, especially in critically ill patients.
Topics: Blood Platelets; Critical Illness; Drug Storage; Humans; Platelet Transfusion; Treatment Outcome
PubMed: 30077181
DOI: 10.1186/s13054-018-2114-x -
Medicine Dec 2021The relationship between platelet-associated parameters and psoriasis has been controversial. The purpose of our meta-analysis was to assess whether platelet count,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The relationship between platelet-associated parameters and psoriasis has been controversial. The purpose of our meta-analysis was to assess whether platelet count, platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), and platelet distribution width (PDW) are associated with psoriasis.
METHODS
We performed a thorough documentation retrieval via PubMed, EMBASE, and Web of Science until June 2021. Pooled standardized mean differences (SMDs) and 95% confidence intervals (CIs) were calculated using a random-effects model.
RESULTS
Overall, 22 studies involving 1749 patients with psoriasis and 1538 healthy controls were selected for the meta-analysis. The outcomes showed that platelet count presented non-significant differences between psoriatic patients and normal individuals (SMD = 0.12, 95% CI = -0.07 to 0.32, P = .210), while PLR (SMD = 0.28, 95% CI = 0.03-0.53, P = .031), MPV (SMD = 0.55, 95% CI = 0.30-0.79, P < .001), and PDW (SMD = 0.29, 95% CI = 0.03-0.55, P = .027) were remarkably greater in the psoriatic patients than in the healthy individuals, and similar results were found in subgroup analyses. The analytical results of susceptibility revealed that the outcomes were robust, and no evidence of substantial publication bias was identified.
CONCLUSION
Patients with psoriasis present significantly higher PLR, MPV, and PDW than healthy individuals, suggesting that psoriasis is accompanied by low-grade systemic inflammation and platelet activation.
Topics: Biomarkers; Blood Platelets; Health Status; Humans; Lymphocyte Count; Mean Platelet Volume; Platelet Count; Psoriasis
PubMed: 34918687
DOI: 10.1097/MD.0000000000028234 -
Aging Jul 2021Platelet activation plays an important role in the progression of pulmonary embolism (PE). Mean platelet volume (MPV) can serve as a marker of platelet activity in... (Meta-Analysis)
Meta-Analysis
Platelet activation plays an important role in the progression of pulmonary embolism (PE). Mean platelet volume (MPV) can serve as a marker of platelet activity in patients with PE. Many studies have reported different results regarding the relationship. Therefore, we aimed to perform a systematic review and meta-analysis to evaluate the relationship between MPV and PE. Two reviewers independently searched relevant articles in databases from inception to April 21, 2021 and identified all studies on MPV and PE as the outcomes of interest. Further, we selected studies meeting the criteria and extracted the data. Of the 2505 publications identified, we included 18 studies after screening. Results showed MPV was significantly higher in patients with PE (0.83 fL, 95% CI: 0.38-1.28, P<0.001) than in controls. The mean difference in MPV between those who died and survivors of PE was 1.23 fL (95% CI: 0.96-1.51, P<0.001). Hence, an increased MPV is associated with PE. MPV could be a useful tool to predict the occurrence and death risk of PE together with other risk factors.
Topics: Biomarkers; Humans; Mean Platelet Volume; Platelet Activation; Predictive Value of Tests; Prognosis; Pulmonary Embolism
PubMed: 34214051
DOI: 10.18632/aging.203205 -
JAMA Dec 2011The US Food and Drug Administration recently recommended that CYP2C19 genotyping be considered prior to prescribing clopidogrel, but the American Heart Association and... (Meta-Analysis)
Meta-Analysis Review
CONTEXT
The US Food and Drug Administration recently recommended that CYP2C19 genotyping be considered prior to prescribing clopidogrel, but the American Heart Association and American College of Cardiologists have argued evidence is insufficient to support CYP2C19 genotype testing.
OBJECTIVE
To appraise evidence on the association of CYP2C19 genotype and clopidogrel response through systematic review and meta-analysis.
DATA SOURCES
PubMed and EMBASE from their inception to October 2011.
STUDY SELECTION
Studies that reported clopidogrel metabolism, platelet reactivity or clinically relevant outcomes (cardiovascular disease [CVD] events and bleeding), and information on CYP2C19 genotype were included.
DATA EXTRACTION
We extracted information on study design, genotyping, and disease outcomes and investigated sources of bias.
RESULTS
We retrieved 32 studies of 42,016 patients reporting 3545 CVD events, 579 stent thromboses, and 1413 bleeding events. Six studies were randomized trials ("effect-modification" design) and the remaining 26 reported individuals exposed to clopidogrel ("treatment-only" design). In treatment-only analysis, individuals with 1 or more CYP2C19 alleles associated with lower enzyme activity had lower levels of active clopidogrel metabolites, less platelet inhibition, lower risk of bleeding (relative risk [RR], 0.84; 95% CI, 0.75-0.94; absolute risk reduction of 5-8 events per 1000 individuals), and higher risk of CVD events (RR, 1.18; 95% CI, 1.09-1.28; absolute risk increase of 8-12 events per 1000 individuals). However, there was evidence of small-study bias (Harbord test P = .001). When analyses were restricted to studies with 200 or more events, the point estimate was attenuated (RR, 0.97; 95% CI, 0.86-1.09). In effect-modification studies, CYP2C19 genotype was not associated with modification of the effect of clopidogrel on CVD end points or bleeding (P > .05 for interaction for both). Other limitations included selective outcome reporting and potential for genotype misclassification due to problems with the * allele nomenclature for cytochrome enzymes.
CONCLUSION
Although there was an association between the CYP2C19 genotype and clopidogrel responsiveness, overall there was no significant association of genotype with cardiovascular events.
Topics: Angioplasty, Balloon, Coronary; Aryl Hydrocarbon Hydroxylases; Cardiovascular Diseases; Clopidogrel; Cytochrome P-450 CYP2C19; Genotype; Hemorrhage; Humans; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Function Tests; Randomized Controlled Trials as Topic; Risk; Thrombosis; Ticlopidine
PubMed: 22203539
DOI: 10.1001/jama.2011.1880 -
Plastic and Reconstructive Surgery.... Dec 2017The addition of platelet-rich plasma (PRP) to adipose tissue may improve fat graft survival, although graft retention rates vary markedly between studies. To what extent...
BACKGROUND
The addition of platelet-rich plasma (PRP) to adipose tissue may improve fat graft survival, although graft retention rates vary markedly between studies. To what extent this outcome heterogeneity reflects differing methodological factors remains unknown. This systematic review aims to synthesize and critically review methodological approaches to autologous PRP and fat cotransplantation in both human and animal studies.
METHODS
In accordance with PRISMA guidelines, Ovid MEDLINE, Scopus, and Cochrane Library databases were searched from inception to April 2017. Data were extracted from all in vivo studies involving autologous PRP and fat cotransplantation. A secondary aim was to assess reporting of technical detail; authors were not contacted to provide missing data.
RESULTS
From 335 articles, 23 studies were included in the qualitative synthesis. Some 21 were performed in humans and 2 in rabbits. Six studies were randomized control trials; the remainder reported on observational data. Methods of PRP extraction and activation varied markedly between studies. Fat graft preparation was comparatively more consistent. Methods of PRP and fat mixing differed significantly, especially with regards to relative volume/volume ratios.
CONCLUSIONS
Our study represents the first systematic review of methodological factors in autologous PRP and fat cotransplantation. It demonstrates that technical factors in graft preparation and administration vary significantly between in vivo studies. Such methodological heterogeneity may explain observed differences in experimental and clinical outcomes. Reporting of key procedural information is inconsistent and often inadequate. These issues make meaningful evaluation of the PRP-enhanced fat grafting literature difficult and may limit its translation into clinical practice.
PubMed: 29632775
DOI: 10.1097/GOX.0000000000001596 -
Clinical Rheumatology May 2023Platelet-rich plasma (PRP) has shown to be clinically effective in the treatment of knee osteoarthritis (OA). Notwithstanding, some inconsistences remain due to... (Meta-Analysis)
Meta-Analysis
Comparison of the clinical effectiveness of activated and non-activated platelet-rich plasma in the treatment of knee osteoarthritis: a systematic review and meta-analysis.
INTRODUCTION/OBJECTIVES
Platelet-rich plasma (PRP) has shown to be clinically effective in the treatment of knee osteoarthritis (OA). Notwithstanding, some inconsistences remain due to methodological differences in PRP preparation such as the use (or not) of activation strategies. We aimed to evaluate whether the use of non-activated PRP would be as effective as activated PRP in patients with knee OA.
METHOD
All randomized, placebo-controlled trials were identified through a search in MEDLINE, EMBASE, Scopus, and Web of Science up to June 2022. Pre- and post-injection pain and function scores were collected. The meta-analysis was conducted with a random-effects model and generic inverse variance method. Effect sizes were estimated using standardized mean differences (SMD).
RESULTS
Fourteen clinical trials involving 1292 subjects were included for meta-analysis. Exogenous activation of PRP revealed a significant pain relief (SMD, - 1.05 [95% CI - 1.58 to - 0.52]; p = 0.0001) and a significant functional improvement (SMD, - 1.21 [95% CI - 1.75 to - 0.67]; p < 0.0001) unlike studies describing the use of a non-activated PRP. The sensitivity analysis indicated that the effect size for both outcomes was not influenced by a single study.
CONCLUSIONS
The results of this systematic review suggest that the use of an exogenously activated PRP is more effective in improving both pain and functional scores in patients with knee OA. Key Points • Results from meta-analysis suggest that exogenously activated PRP is clinically more effective than non-activated PRP. • The use of an activated PRP was more frequently reported by the included studies. • The most frequent method for activation was the use of calcium chloride (CaCl).
Topics: Humans; Osteoarthritis, Knee; Treatment Outcome; Pain; Injections, Intra-Articular; Platelet-Rich Plasma; Hyaluronic Acid
PubMed: 36502442
DOI: 10.1007/s10067-022-06463-x -
Lipids in Health and Disease May 2019Combination of statins and clopidogrel is frequently administered in patients with coronary artery disease (CAD). They are mainly activated and eliminated in the liver... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Combination of statins and clopidogrel is frequently administered in patients with coronary artery disease (CAD). They are mainly activated and eliminated in the liver by cytochrome P450 isoenzyme 3A4 (CYP3A4). The aim was to clarify whether the coadministration of clopidogrel and statins attenuate respective efficacy.
METHODS
PubMed, Embase, the Cochrane Library, Web of Science and Clinical Trials. gov were searched for until August 2018. Randomized controlled trials (RCTs) and cohort studies were taken into quality evaluation. Data were pooled using random effect models to estimate standard mean difference (SMD) or risk ratio (RR) with 95% confidence interval (CI).
RESULTS
In total, 28 studies representing 25,267 participants were included. Statins reduce the mortality of patients administered clopidogrel (RR 0.54; 95% CI 0.40,0.74; p = 0.000), no differences were found in platelet aggregation (PA) (SMD 0.02; 95% CI -0.38,0.42; p = 0.920) and the expressions of P-selectin (SMD -0.04; 95% CI -0.14,0.05; p = 0.346), CD40L (SMD 0.09; 95% CI -0.29,0.48; p = 0.633), CD63 (SMD 0.09; 95% CI -0.01,0.19; p = 0.079) and PAC-1 (SMD 0.03; 95% CI -0.08,0.13; p = 0.633). Furthermore, CYP3A4 metabolized or non-CYP3A4 metabolized statins have no discrepancies in PA (SMD 0.13; 95% CI -0.31,0.58; p = 0.556), P-selectin (SMD 0.17; 95% CI -0.16,0.51; p = 0310), death (RR 0.89; 95% CI 0.38,2.07; p = 0.791), except for triglyceride (TG) (SMD -0.19; 95% CI -0.33,-0.06; p = 0.005).
CONCLUSIONS
This meta-analysis confirmed that statins reduce mortality in patients undergoing clopidogrel treatment without affecting platelet activation and aggregation.
Topics: Clopidogrel; Cytochrome P-450 CYP3A; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lipid Metabolism; Mortality; Platelet Aggregation; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 31122249
DOI: 10.1186/s12944-019-1053-0 -
International Journal of Molecular... Jun 2023Through a process termed , platelets cause thrombi to shrink and become more stable. After platelets are activated via inside-out signaling, glycoprotein αIIbβIII...
Through a process termed , platelets cause thrombi to shrink and become more stable. After platelets are activated via inside-out signaling, glycoprotein αIIbβIII binds to fibrinogen and initiates a cascade of intracellular signaling that ends in actin remodeling, which causes the platelet to change its shape. Clot retraction is also important for wound healing. Although the detailed molecular biology of clot retraction is only partially understood, various substances and physiological conditions modulate clot retraction. In this review, we describe some of the current literature pertaining to clot retraction modulators. In addition, we discuss compounds from , , and that diminish clot retraction and have numerous other health benefits. Caffeic acid and diindolylmethane, both common in plants and vegetables, likewise reduce clot retraction, as do all-trans retinoic acid (a vitamin A derivative), two MAP4K inhibitors, and the chemotherapeutic drug Dasatinib. Conversely, the endogenous anticoagulant Protein S (PS) and the matricellular protein secreted modular calcium-binding protein 1 (SMOC1) both enhance clot retraction. Most studies aiming to identify mechanisms of clot retraction modulators have focused on the increased phosphorylation of vasodilator-stimulated phosphoprotein and inositol 1,4,5-triphosphate receptor I and the decreased phosphorylation of various phospholipases (e.g., phospholipase A2 (PLA) and phosphatidylinositol-specific phospholipase Cγ2 (PLCγ), c-Jun N-terminal kinase, and (PI3Ks). One study focused on the decreased phosphorylation of Sarcoma Family Kinases (SFK), and others have focused on increased cAMP levels and the downregulation of inflammatory markers such as thromboxanes, including thromboxane A2 (TXA) and thromboxane B2 (TXB); prostaglandin A2 (PGE2); reactive oxygen species (ROS); and cyclooxygenase (COX) enzyme activity. Additionally, pregnancy, fibrinolysis, and the autoimmune condition systemic lupus erythematosus all seem to affect, or at least have some relation with, clot retraction. All the clot retraction modulators need in-depth study to explain these effects.
Topics: Blood Platelets; Clot Retraction; Phosphorylation; Platelet Aggregation; Signal Transduction
PubMed: 37445780
DOI: 10.3390/ijms241310602 -
Frontiers in Cardiovascular Medicine 2019Despite increasing technical improvement and extracorporeal membrane oxygenation (ECMO)-related knowledge over the past three decades, morbidity and mortality...
Despite increasing technical improvement and extracorporeal membrane oxygenation (ECMO)-related knowledge over the past three decades, morbidity and mortality associated with bleeding and clotting complications remain high in pediatric patients undergoing ECMO. Platelets, a key element of the coagulation system, have been proposed to be the main cause of coagulopathy in the setting of ECMO. This systematic review aims to summarize and discuss the existing knowledge of platelet phenotype and function in the pediatric ECMO population. A systematic review was conducted for the Embase, Medline, and PubMed databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The detailed study selection process yielded a total of 765 studies and only 3 studies that fulfilled the selection criteria were included in this review. Techniques used to assess platelet function in the three existing studies included platelet aggregometry, flow cytometry, and thromboelastography-platelet mapping. The finding that is common to the three studies is reduced platelet function in pediatric patients during ECMO either compared to before the initiation of ECMO or in non-survivors compared to survivors. Two studies demonstrated reduced platelet aggregation that are irreversible by platelet transfusion during ECMO. Two studies reported bleeding events and mortality in children on ECMO and none of the studies investigated thrombotic events. This systematic review demonstrates the extremely limited information available for platelet phenotype and function in the pediatric ECMO population. Evidence from the existing literature suggests reduced platelet aggregation and increased platelet activation in children during ECMO. However, this needs to be interpreted with care due to the limitations associated with the techniques used for platelet function testing. Furthermore, the association between platelet dysfunction and clinical outcomes in the pediatric ECMO population remains elusive. Multiple research gaps have been identified when it comes to the knowledge of platelet phenotype and function of children on ECMO, highlighting the need for robust, well-designed studies in this setting.
PubMed: 31620448
DOI: 10.3389/fcvm.2019.00137 -
Journal of Thrombosis and Haemostasis :... May 2014Antiplatelet therapy is the standard treatment for the prevention of cardiovascular events (CVEs). High on-treatment platelet reactivity (HPR) is a risk factor for... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Antiplatelet therapy is the standard treatment for the prevention of cardiovascular events (CVEs). High on-treatment platelet reactivity (HPR) is a risk factor for secondary CVEs in patients prescribed aspirin and/or clopidogrel. The present review and meta-analysis was aimed at assessing the ability of individual platelet-function tests to reliably identify patients at risk of developing secondary CVEs.
METHODS AND RESULTS
A systematic literature search was conducted to identify studies on platelet-reactivity measurements and CVEs. The main inclusion criteria were: (i) prospective study design; (ii) study medication, including aspirin and/or clopidogrel; and (iii) a platelet-function test being performed at baseline, before follow-up started. Of 3882 identified studies, 102 (2.6%; reporting on 44 098 patients) were included in the meta-analysis. With regard to high on-aspirin platelet reactivity (HAPR), 22 different tests were discussed in 55 studies (22 441 patients). Pooled analysis showed that HAPR was diagnosed in 22.2% of patients, and was associated with an increased CVE risk (relative risk [RR] 2.09; 95% confidence interval [CI] 1.77-2.47). Eleven HAPR tests independently showed a significantly increased CVE risk in patients with HAPR as compared with those with normal on-aspirin platelet reactivity. As regards high on-clopidogrel platelet reactivity (HCPR), 59 studies (34 776 patients) discussed 15 different tests, and reported that HCPR was present in 40.4% of patients and was associated with an increased CVE risk (RR 2.80; 95% CI 2.40-3.27). Ten tests showed a significantly increased CVE risk.
CONCLUSIONS
Patients with HPR are suboptimally protected against future cardiovascular complications. Furthermore, not all of the numerous platelet tests proved to be able to identify patients at increased cardiovascular risk.
Topics: Aspirin; Blood Platelets; Cardiovascular Diseases; Clopidogrel; Coronary Artery Disease; Humans; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Function Tests; Prospective Studies; Risk Factors; Ticlopidine
PubMed: 24612413
DOI: 10.1111/jth.12538