ABSTRACT
BACKGROUND: Atherothrombotic disease is the leading cause of death worldwide. Most casualties are due to acute myocardial infarction (AMI). Patients younger than 45 years account for 5-10% of AMI cases. These patients generally do not display typical atherothrombotic risk factors. METHODS: Our cross-sectional study included adult patients under 45; men and women with AMI were included. A control group of healthy individuals matched for age, sex, and blood group was included to determine the role of several atherothrombotic risk factors on AMI. One hundred and sixty patients were included, the control group was comprised by 77 males (m) and 83 females (f) RESULTS: Our results indicate that 25% of patients (23 m and 18 f) had increased FVIII compared with 8.8% of control subjects. Mean FVIII activity for patients and controls was 134 mg/dl (95%CI=114) vs. 118 mg/dl (95%CI=128-140), respectively (p=0.001). Prevalence of elevated FVIII was higher than the one found for hypertension or diabetes mellitus. HDL cholesterol was higher among patients than controls. Quantitative variables associated with AMI were high FVIII activity, blood monocyte count and HDL cholesterol. CONCLUSIONS: Classical atherothrombotic risk factors do not fully explain AMI events in the young. High levels of FVIII activity is a moderate but common risk factor in young people suffering AMI.
Subject(s)
Factor VIII/analysis , Myocardial Infarction/blood , Adult , Cross-Sectional Studies , Female , Humans , Male , Mexico , Middle Aged , Risk FactorsABSTRACT
Antecedentes: La enfermedad aterotrombótica es la causa de muerte más frecuente y la mayoría corresponde a infarto agudo del miocardio (IAM). Los menores de 45 años representan 5 a 10% de los IAM y es común que no sean portadores de factores de riesgo aterotrombótico clásicos. Métodos: Este estudio transversal analítico incluyó pacientes menores de 45 años con IAM, de uno y otro sexo, pareados por edad, sexo y grupo sanguíneo con sus respectivos controles, para analizar el impacto de diferentes factores de riesgo aterotrombótico sobre el IAM. Incluimos 160 casos y controles, 77 hombres y 83 mujeres. Resultados: El 25% de los pacientes tuvo aumento del factor VIII de la hemostasia (FVIII) vs. 8.8% en los controles. El FVIII promedio para pacientes y controles fue 134 mg/dl (IC 95%=114) vs. 118 mg/dl (IC 95%=128-140), respectivamente (p=0.001). La prevalencia de actividad alta del FVIII fue mayor que la de diabetes mellitus o hipertensión arterial. Paradójicamente, el colesterol HDL fue mayor en los pacientes que en los controles. Las únicas variables cuantitativas asociadas a IAM fueron la actividad alta del FVIII, la cuenta de monocitos en sangre periférica y el colesterol HDL. Conclusiones: Los factores de riesgo aterotrombótico clásicos no explican totalmente el IAM en jóvenes. El aumento de FVIII es un factor de riesgo moderado pero frecuente en la población joven con IAM.
BACKGROUND: Atherothrombotic disease is the leading cause of death worldwide. Most casualties are due to acute myocardial infarction (AMI). Patients younger than 45 years account for 5-10% of AMI cases. These patients generally do not display typical atherothrombotic risk factors. METHODS: Our cross-sectional study included adult patients under 45; men and women with AMI were included. A control group of healthy individuals matched for age, sex, and blood group was included to determine the role of several atherothrombotic risk factors on AMI. One hundred and sixty patients were included, the control group was comprised by 77 males (m) and 83 females (f) RESULTS: Our results indicate that 25% of patients (23 m and 18 f) had increased FVIII compared with 8.8% of control subjects. Mean FVIII activity for patients and controls was 134 mg/dl (95%CI=114) vs. 118 mg/dl (95%CI=128-140), respectively (p=0.001). Prevalence of elevated FVIII was higher than the one found for hypertension or diabetes mellitus. HDL cholesterol was higher among patients than controls. Quantitative variables associated with AMI were high FVIII activity, blood monocyte count and HDL cholesterol. CONCLUSIONS: Classical atherothrombotic risk factors do not fully explain AMI events in the young. High levels of FVIII activity is a moderate but common risk factor in young people suffering AMI.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Factor VIII/analysis , Myocardial Infarction/blood , Cross-Sectional Studies , Mexico , Risk FactorsABSTRACT
A common cause of hereditary thrombophilia is activated protein C resistance (APCR), and most cases result from factor V Leiden mutation. An APCR phenotype without association with factor V Leiden has been described. This transversal, observational, nonrandomized study evaluated these 2 phenomena in healthy indigenous and mestizo Mexican subjects (n = 4345), including 600 Mexican natives. No indigenous subjects had APCR, but 82 mestizo subjects did. After retesting, 50 subjects had a negative test. The remaining 32 subjects had factor V Leiden, giving a 0.85% prevalence of factor V Leiden in the mestizo Mexican population. Only 31% of APCR carriers had factor V Leiden. These results show a very low prevalence of APCR and factor V Leiden in Mexico. Except for factor V Leiden, there are no other mutations in the factor V gene responsible for the APCR phenotype. Acquired APCR is nearly twice as prevalent as the inherited variant.
Subject(s)
Activated Protein C Resistance/epidemiology , Factor V/analysis , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Mexico/epidemiology , Middle Aged , PrevalenceABSTRACT
This is a broad review of sources of error in the coagulation tests, all of which must be considered, evaluated and supervised to improve their quality. The analytical result of a laboratory examination is a scientific fact and has no medical meaning as such. It must be interpreted to become a medical finding. Recent improvement in equipment, reagents, and the fact that hemophilic and thrombotic events are considered the main causes of death are the principal reasons to prepare this article. The internal quality control program considers this fact because its beginning starts when the physician makes the request to the lab; moreover, the clinical interpretation of the results of the laboratory represents the end of the cycle. Outcome of clinical test in hemostasis is critically dependent upon the quality of the sample, the method, the instruments, the reagents and the personnel involved in the performance of the test. Use of high quality blood collection procedures and an awareness of preanalytic errors are presented to lead to quality outcomes. Today, performance of internal and external quality control programs is obligatory.
Subject(s)
Blood Coagulation Tests/standards , Diagnostic Errors , Humans , Quality ControlABSTRACT
Thrombophilia or prothrombotic state appears when activation of blood hemostatic mechanisms overcomes the physiological anticoagulant capacity allowing a thrombotic event. Thrombosis is the leading worldwide mortality cause and due to its high associated morbidity and mortality, it should be insisted in the opportune identification of a thrombophilic state. The study of thrombophilia identifies individuals at high risk for thrombosis. This meeting was conceived first to analyze the current status of the diagnosis of thrombophilia in Mexico and second to create the base for a national consensus for thrombophilia screening and for the establishment of a national center for laboratory reference and quality control for thrombophilia. Since searching of activated protein C resistance (APCR) and FV Leiden seem to have priority either in the clinical setting and in public health services, it was decided to start with these two abnormalities as a model to analyze the current status of thrombophilia diagnosis in the clinical laboratory. At this time, several thrombophilic abnormalities have been described however, APCR remains the most important cause of thrombophilia, accounting for as much as 20% to 60% of all venous thrombosis. APCR is a consequence of the resistance of activated FV to be inactivated by activated protein C. Procoagulant activity of activated FV increases the risk of thrombosis. Hereditary APCR is almost always due to a point mutation at the nucleotide 1691 of the FV gen inducing an Arg506Glu substitution in FV molecule. This mutation is better known as FV Leiden. Heterocygous carriers of FV Leiden have a thrombotic risk 5 to 10 times higher than general population while the risk for the homocygote state is increased 50 to 100-fold. When activated PC is added to plasma from patients with FV Leiden, this last resists the anticoagulant effect of activated PC. Therefore, thrombin production is not inhibited. This phenomenon is called APCR. The functional test evaluates the partially activated thromboplastin time (aPTT) in a plasma sample before and after adding activated PC. The result is reported as a standardized sensibility index: aPTT post-activated PC/aPTT pre-activated PC. The conclusions of this national reunion pretend to optimize the available resources in our country in order to allow a wide and less-expensive diagnosis of patients with thrombosis.
