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The hematologic consequences of obesity. Purdy Johanna C,Shatzel Joseph J European journal of haematology The prevalence of obesity is increasing and progressively influencing physician-patient interactions. While there is a sizable amount of data demonstrating that obesity is a state of low-grade inflammation, to our knowledge, there is no single review summarizing its effects on hematologic parameters and thrombotic risk. We performed a literature search which largely surfaced observational studies, with a few systematic reviews and meta-analyses of these studies. We took care to review the mechanisms driving an inflammatory state and obesity's effect on white blood cells, red blood cells, platelets, and thrombotic risk. There is an observed relative, and sometimes absolute leukocytosis driven by this inflammatory state. Obesity is also associated with increased platelet counts and an increased risk for venous thromboembolism (VTE). Lastly, the association between obesity, iron deficiency (ID), and red blood cell counts may be present but remains uncertain. Recognizing the above associations may provide clinicians with reassurance regarding otherwise unexplained hematologic abnormalities in obese individuals. We hope this review will prompt future studies to further understand the underlying mechanisms driving these abnormalities and identify modifiable risk factors and potential therapeutic targets to prevent the development of probable obesity-associated conditions with significant morbidity and mortality, such as ID and VTE. 10.1111/ejh.13560
Variation of platelet function in clinical phenotypes of acute venous thromboembolism - Results from the GMP-VTE project. Journal of thrombosis and haemostasis : JTH BACKGROUND:The role of platelets in the pathogenesis of venous thromboembolism (VTE) is receiving increasing attention; however, limited information is available on platelet function in the acute phase of the disease. OBJECTIVE:To characterize platelet function according to VTE phenotypes. PATIENTS/METHODS:In total, 154 subjects (isolated pulmonary embolism [iPE], n = 28; isolated deep vein thrombosis [iDVT], n = 35; DVT+PE, n = 91) were included. In this study platelet function analyzer (PFA)-200, light transmission aggregometry (LTA), thrombin generation (TG) in presence (PRP) and absence (PFP) of platelets and platelet flow cytometry were investigated. LASSO regression was used to select clinical and platelet biomarkers that distinguish between VTE phenotypes. RESULTS:PFA-200 results did not differ between VTE phenotypes. LTA from DVT+PE subjects showed lowest maximum aggregation after epinephrine and adenosine diphosphate compared to iPE and iDVT. Lower % of PAC-1-positive platelets after in-vitro trigger were present in DVT+PE and iPE compared to iDVT. TG in PRP had lower peak height and velocity in DVT+PE and iPE against iDVT. The results of LASSO regression for the distinction between DVT+PE vs iDVT identified 18 variables (AUC =0.93) of which 72% were platelet biomarkers. For distinction between iPE and iDVT, 10 variables were selected (AUC = 0.96) of which 50% were platelet-related. Obesity was the only variable weakly discriminating between DVT+PE vs iPE (AUC = 0.66). CONCLUSION:This explorative study suggests an important distinction between PE-related phenotypes and iDVT when considering clinical and platelet function data. Lower platelet-dependent TG along with reduced platelet reactivity suggest higher platelet degranulation in PE-dependent phenotypes compared to iDVT. 10.1111/jth.15595
Associations Between Mean Platelet Volume and Various Factors in Type 2 Diabetes Patients: A Single-Center Study from Poland. Medical science monitor : international medical journal of experimental and clinical research BACKGROUND Thromboembolic episodes, which are largely mediated by blood platelets, are prevalent chronic complications of diabetes. The mean platelet volume (MPV) serves as a marker for in vivo platelet activation. This study aimed to assess the factors influencing MPV in 106 patients with type 2 diabetes, compared with 59 non-diabetic individuals at a single center in Poland. MATERIAL AND METHODS We performed linear regression analysis, with MPV as the dependent variable and factors such as age, sex, thrombopoiesis-influencing cytokines, blood pressure, body mass index, glycosylated hemoglobin percentage, platelet count, large platelet count, lipid profile parameters, creatinine concentration, estimated glomerular filtration rate, treatment modalities, and comorbidities as independent variables. MPV was measured using the ADVIA 2120 hematology analyzer, with a reference range of 7-12 fL. RESULTS The analysis revealed that in patients with type 2 diabetes, an increase in platelet count by 10×10³/μL resulted in a decrease in MPV by 0.05 (P<0.001), while an increase in large platelet count by 1×10³/μL led to an increase in MPV by 0.18 (P<0.001). Additionally, patients taking ß-blockers or insulin had lower MPVs by 0.77 (P=0.008) and 5.63 (P<0.001), respectively, compared with those not on these medications. CONCLUSIONS This study delineates the relationship between MPV, platelet parameters, and treatment modalities in type 2 diabetes, paving the way for further research to elucidate underlying mechanisms and potential clinical applications. 10.12659/MSM.941109
Type 2 Diabetes Mellitus, Platelet Activation and Alzheimer's Disease: A Possible Connection. Clinical neuropsychiatry Type 2 diabetes mellitus DM (T2DM) is associated with a 70% increased risk for dementia, including Alzheimer's disease (AD). Insulin resistance has been proposed to play a pivotal role in both T2DM and AD and the concept of "brain insulin resistance" has been suggested as an interpretation to the growing literature regarding cognitive impairment and T2DM. Subjects with T2DM present an abnormal platelet reactivity that together with insulin resistance, hyperglycaemia and dyslipidaemia effect the vascular wall by a series of events including endothelial dysfunction, oxidative stress and low-grade inflammation. Activated platelets directly contribute to cerebral amyloid angiopathy (CAA) by promoting the formation of β-amyloid (Aβ) aggregates and that Aβ, in turn, activates platelets, creating a feed-forward loop suggesting the involvement of platelets in the AD pathogenesis. Moreover, islet amyloid polypeptide deposition, co-localized with Aβ deposits, is a common finding in the brain of patients with T2DM. These observations raise the intriguing prospect that traditional or novel antiplatelet therapeutic strategies may alleviate fibril formation and could be used in the prevention or treatment of AD subjects with diabetes. 10.36131/cnfioritieditore20220604
Platelet Measurements and Type 2 Diabetes: Investigations in Two Population-Based Cohorts. Rodriguez Benjamin A T,Johnson Andrew D Frontiers in cardiovascular medicine Type 2 diabetes is a major risk factor for cardiovascular disease. Given the contribution of platelets to atherothrombosis-which in turn is a major contributor to cardiac events, there may be cause to consider platelet function in management of diabetes. Despite the large body of research concerning the role of platelets in cardiovascular complications of type 2 diabetes, evidence from population-based studies of platelet aggregation in diabetes is limited. Mean Platelet Volume (MPV), a cell trait partially associated with markers of platelet activity, is more commonly available. We investigated the association of metabolic syndrome and diabetes with platelet aggregation to three physiological agonists, ADP, collagen, and epinephrine, in the Framingham Heart Study Offspring cohort. We further examined the relationship between MPV measured with Beckman Coulter LH750 instruments and self-reported diabetes as well as MPV and diabetes medication in the UK BioBank cohort, performing the largest such analysis to date. Increased platelet aggregation associated with prevalent diabetes was observed for low concentration epinephrine (0.1 μM) alone and only in analyses of participants stratified either by male sex and/or having metabolic syndrome. Other agonists and concentrations were not significant for prevalent diabetes, or in opposite direction to the main hypothesis (i.e., they showed lower platelet aggregation associated with diabetes). After a median of 18.1 years follow-up, no platelet aggregation trait was associated with increased risk of diabetes ( = 344 cases). As expected, increased MPV was significantly associated with diabetes (β = 0.0976; = 8.62 × 10). Interestingly, sex-stratified analyses indicated the association of MPV with diabetes is markedly stronger in males (β = 0.1232; = 1.00 × 10) than females (β = 0.0514; = 7.37 × 10). Among diabetes medications increased MPV was associated with Insulin (β = 0.1341; = 1.38 × 10) and decreased MPV with both Metformin (β = 0.0763; = 1.99 × 10) as well as the sulphonylureas (β = 0.0559; = 0.0034). Each drug showed the same direction of effect in both sexes, however, the association with MPV was nearly twice as great or more in women compared to men. In conclusion, platelet function as measured by aggregation to ADP, collagen, or epinephrine does not appear to be consistently associated with diabetes, however, MPV is robustly associated suggesting future work may focus on how MPV segments pre-diabetics and diabetics for risk prediction. 10.3389/fcvm.2020.00118
Angiogenesis, Metabolism, Endothelial and Platelet Markers in Diabetes and Cardiovascular Disease. British journal of biomedical science Diabetes is a leading risk factor for cardiovascular disease (CVD), the pathophysiology of both being linked to metabolic, endothelial, renal, angiogenic and platelet abnormalities. We hypothesised that abnormalities in these systems are more adverse in those whose CVD is compounded by diabetes, compared to those with diabetes or CVD alone. Serum or plasma from 66 patients with diabetes alone, 76 with CVD alone, and 70 with both diabetes and CVD i.e. diabetic cardiovascular disease, was probed for markers of angiogenesis [angiopoietin 1 and 2, vascular endothelial growth factor (VEGF) and endoglin], metabolic [soluble receptor for advanced glycation products (sRAGE), leptin, lipocalin-2, interleukin-8, and cystatin-C], the endothelium (von Willebrand factor, endothelial microparticles and soluble E selectin)], and the platelet (platelet microparticles and soluble P selectin) by ELISA, Luminex or flow cytometry. VEGF ( = 0.04), von Willebrand factor ( = 0.001) and endothelial microparticles ( = 0.042) were all higher in diabetic cardiovascular disease than in diabetes alone and cardiovascular disease alone. Soluble E selectin was higher in diabetic cardiovascular disease than in diabetes alone ( = 0.045), whilst cystatin-C ( = 0.004) and soluble P selectin ( < 0.001) were higher in diabetes and diabetic cardiovascular disease than in cardiovascular disease alone. There were no differences in angiopoietin 1 or 2, endoglin, sRAGE, leptin, lipocalin-2, or interleukin-8. Angiopoietin 1 or 2, endoglin, sRAGE, leptin, lipocalin-2, interleukin-8, and cystatin-c cannot differentiate diabetes from cardiovascular disease, or both conditions combined. Our data point to a more adverse endothelial (von Willebrand factor, endothelial microparticles), and angiogenic profile (VEGF) in those with diabetic cardiovascular disease, supporting the view that this group should be targeted more aggressively. 10.3389/bjbs.2022.10313
Platelets in aging and cancer-"double-edged sword". Cancer metastasis reviews Platelets control hemostasis and play a key role in inflammation and immunity. However, platelet function may change during aging, and a role for these versatile cells in many age-related pathological processes is emerging. In addition to a well-known role in cardiovascular disease, platelet activity is now thought to contribute to cancer cell metastasis and tumor-associated venous thromboembolism (VTE) development. Worldwide, the great majority of all patients with cardiovascular disease and some with cancer receive anti-platelet therapy to reduce the risk of thrombosis. However, not only do thrombotic diseases remain a leading cause of morbidity and mortality, cancer, especially metastasis, is still the second cause of death worldwide. Understanding how platelets change during aging and how they may contribute to aging-related diseases such as cancer may contribute to steps taken along the road towards a "healthy aging" strategy. Here, we review the changes that occur in platelets during aging, and investigate how these versatile blood components contribute to cancer progression. 10.1007/s10555-020-09926-2
Anticoagulant treatment of cancer-associated thromboembolism. Archives of cardiovascular diseases Venous thromboembolism (VTE) is a frequent and potentially fatal complication in patients with cancer. During the initial period after the thromboembolic event, a patient receiving anticoagulant treatment is exposed both to a risk of VTE recurrence and also to an elevated bleeding risk conferred by the treatment. For this reason, the choice of anticoagulant is critical. The choice should take into account patient-related factors (such as functional status, age, body mass index, platelet count and renal function), VTE-related factors (such as severity or site), cancer-related factors (such as activity and progression) and treatment-related factors (such as drug-drug interactions), which all potentially influence bleeding risk, and patient preference. These should be evaluated carefully for each patient during a multidisciplinary team meeting. For most patients, apixaban or a low molecular-weight heparin is the most appropriate initial choice for anticoagulant treatment. Such treatment should be offered to all patients with active cancer for at least six months. The patient and treatment should be re-evaluated regularly and anticoagulant treatment changed when necessary. Continued anticoagulant treatment beyond six months is justified if the cancer remains active or if the patient experienced recurrence of VTE in the first six months. In other cases, the interest of continued anticoagulant treatment may be considered on an individual patient basis in collaboration with oncologists. 10.1016/j.acvd.2023.11.010
Involvement of Platelets in Cancers. Mege Diane,Aubert Mathilde,Lacroix Romaric,Dignat-George Françoise,Panicot-Dubois Laurence,Dubois Christophe Seminars in thrombosis and hemostasis Cancer-related venous thromboembolism (VTE) is frequent and constitutes the second leading cause of death in patients with cancer. High platelet count is one of independent predictive factors of cancer-associated VTE. Besides the implication of platelets in cancer-associated VTE, recent clinical and experimental evidences support that platelets play several roles in the progression of malignancies and inversely, cancer can also influence platelet count and activity. The objective of this report is to review the current literature regarding the role of platelets in cancer through experimental results and population-based studies. Platelets are implicated in cancer progression and metastasis through proangiogenic factors (growth factors and signaling pathways), antiangiogenic factors (angiostatin, endostatin, thrombospondin-1), and matrix metalloproteinases. In addition, platelets are involved in cancer-associated thrombosis and thus tumor cell-induced platelet activation, through anionic phospholipids on their surface, released soluble factors, such as P-selectin, CD40 ligand, platelet factor 4, thrombospondin-1 or beta-thromboglobulin, tumor cell procoagulant proteins (tissue factor, urokinase-type plasminogen activator, plasminogen activator inhibitor type 1), and microparticles. Due to these different mechanisms, platelets may represent a potential therapeutic target. The main current treatments against platelets are: (1) acetylsalicylic acid (aspirin) and nonsteroidal anti-inflammatory drugs, nonselective cyclo-oxygenase (COX)-1 and COX-2 inhibitors, which are associated with decreased cancer incidence and better overall survival and (2) irreversible inhibitor of P2Y12 subtype which decreases cancer incidence. Platelets are key players in tumor growth, metastasis, and cancer-associated thrombosis. This multifaceted role identifies them as a relevant therapeutic target for prevention of cancer occurrence and treatment of cancer. 10.1055/s-0039-1693475
Cancer-associated venous thromboembolism: Burden, mechanisms, and management. Ay Cihan,Pabinger Ingrid,Cohen Alexander T Thrombosis and haemostasis Venous thromboembolism (VTE) is a significant health problem in the general population but especially in cancer patients. In this review, we discuss the epidemiology and burden of the disease, the pathophysiology of cancer-associated VTE, and the clinical treatment options for both primary prevention and acute treatment. Overall, the development of VTE in cancer patients is related to increases in morbidity, mortality, and medical costs. However, the incidence of cancer-associated VTE varies due to patient-related factors (e.g. thrombophilia, comorbidities, performance status, history of venous diseases), tumour-related factors (e.g. cancer site, stage, grade), and treatment-related factors (e.g. surgery, chemotherapy, anti-angiogenesis treatment, hormonal and supportive treatment). Furthermore, blood count parameters (e.g. platelets and leukocytes) and biomarkers (e.g. soluble P-selectin and D-dimer) are predictive markers for the risk of VTE in cancer patients and have been used to enhance risk stratification. Evidence suggests that cancer itself is associated with a state of hypercoagulability, driven in part by the release of procoagulant factors, such as tissue factor, from malignant tissue as well as by inflammation-driven activation of endothelial cells, platelets, and leukocytes. In general, low-molecular-weight heparin (LWMH) monotherapy is the standard of care for the management of cancer-associated VTE, as vitamin K antagonists are less effective in cancer patients. Direct oral anticoagulants (DOACs) offer a potentially promising treatment option for cancer patients with VTE, but recommendations concerning the routine use of DOACs should await head-to-head studies with LMWH. 10.1160/TH16-08-0615
Cancer-associated pathways and biomarkers of venous thrombosis. Blood Cancer patients have an increased risk of venous thromboembolism (VTE). In this review, we summarize common and cancer type-specific pathways of VTE in cancer patients. Increased levels of leukocytes, platelets, and tissue factor-positive (TF) microvesicles (MVs) are all potential factors that alone or in combination increase cancer-associated thrombosis. Patients with lung or colorectal cancer often exhibit leukocytosis. Neutrophils could increase VTE in cancer patients by releasing neutrophil extracellular traps whereas monocytes may express TF. Thrombocytosis is often observed in gastrointestinal, lung, breast, and ovarian cancer and this could decrease the threshold required for VTE. Soluble P-selectin has been identified as a biomarker of cancer-associated thrombosis in a general cancer population and may reflect activation of the endothelium. P-selectin expression by the endothelium may enhance VTE by increasing the recruitment of leukocytes. Studies in patients with pancreatic or brain cancer suggest that elevated levels of PAI-1 may contribute to VTE. Although elevated levels of TF MVs have been observed in patients with different types of cancer, an association between TF MVs and VTE has been observed only in pancreatic cancer. Podoplanin expression is associated with VTE in patients with brain cancer and may activate platelets. Future studies should measure multiple biomarkers in each cancer type to determine whether combinations of biomarkers can be used as predictors of VTE. A better understanding of the pathways that increase VTE in cancer patients may lead to the development of new therapies to reduce the morbidity and mortality associated with thrombosis. 10.1182/blood-2017-03-743211
Cancer-associated venous thromboembolism. Nature reviews. Disease primers Cancer-associated thrombosis (including venous thromboembolism (VTE) and arterial events) is highly consequential for patients with cancer and is associated with worsened survival. Despite substantial improvements in cancer treatment, the risk of VTE has increased in recent years; VTE rates additionally depend on the type of cancer (with pancreas, stomach and primary brain tumours having the highest risk) as well as on individual patient's and cancer treatment factors. Multiple cancer-specific mechanisms of VTE have been identified and can be classified as mechanisms in which the tumour expresses proteins that alter host systems, such as levels of platelets and leukocytes, and in which the tumour expresses procoagulant proteins released into the circulation that directly activate the coagulation cascade or platelets, such as tissue factor and podoplanin, respectively. As signs and symptoms of VTE may be non-specific, diagnosis requires clinical assessment, evaluation of pre-test probability, and objective diagnostic testing with ultrasonography or CT. Risk assessment tools have been validated to identify patients at risk of VTE. Primary prevention of VTE (thromboprophylaxis) has long been recommended in the inpatient and post-surgical settings, and is now an option in the outpatient setting for individuals with high-risk cancer. Anticoagulant therapy is the cornerstone of therapy, with low molecular weight heparin or newer options such as direct oral anticoagulants. Personalized treatment incorporating risk of bleeding and patient preferences is essential, especially as a diagnosis of VTE is often considered by patients even more distressing than their cancer diagnosis, and can severely affect the quality of life. Future research should focus on current knowledge gaps including optimizing risk assessment tools, biomarker discovery, next-generation anticoagulant development and implementation science. 10.1038/s41572-022-00336-y