RESUMEN
BACKGROUND & PURPOSE: Hyperhomocysteinaemia has been postulated to participate in pathogenesis of ischaemic stroke (IS). However, especially in young adults, there is possibility of significantly increased IS risk due to increased normal homocysteinaemia, i.e., hidden (pathologically dormant) prevalence within a healthy, normally-defined range. We performed a post-hoc modelling investigation on plasma total homocysteinaemia (THCY) in gender- and age-matched young patients in the acute IS phase. We evaluated relationships between THCY and prevalence of other potential risk factors in 41 patients vs. 41 healthy controls. METHOD: We used clinical methods, instrumental and neuroimmaging procedures, risk factors examination, total plasma homocysteine measurements and other laboratory and statistical modelling techniques. RESULTS: IS patients and healthy controls were similar not only for matching variables, but also for smoking, main vitamin status, serum creatinine and lipid profile. Patients with IS, however, had lower vitamin B6 levels and higher THCY, fibrinogen and triglycerides (TGL). At multivariate stepwise logistic regression only increased THCY and TGL were significantly and independently associated with the risk for stroke (72% model accuracy, p model=0.001). An increase of THCY with 1.0 micromol/L was associated with 22% higher risk of ischaemic stroke [adjusted OR=1.22 (95%CI 1.03?1.44)]. In this way, novel lower cut-off value for HCY of 11.58 micromol/L in younger patients has been revealed (ROC AUC= 0.67, 95CI% 0.55-0.78, p=0.009). CONCLUSION: The new THCY cut-off clearly discriminated between absence and presence of IS (sensitivity>63%, specificity>68%) irrespectively of age and gender and may be applied to better evaluate and more precisely define, as earlier as possible, the young patients at increased IS risk.
Asunto(s)
Isquemia Encefálica/sangre , Homocisteína/sangre , Enfermedad Aguda , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Valores de Referencia , Factores de RiesgoRESUMEN
BACKGROUND & PURPOSE: Hyperhomocysteinaemia has been postulated to participate in pathogenesis of ischaemic stroke (IS). However, especially in young adults, there is possibility of significantly increased IS risk due to increased ænormalÆ homocysteinaemia, i.e., æhiddenÆ (æpathologically dormantÆ) prevalence within a healthy, normally-defined range. We performed a post-hoc modelling investigation on plasma total homocysteinaemia (THCY) in gender- and age-matched young patients in the acute IS phase. We evaluated relationships between THCY and prevalence of other potential risk factors in 41 patients vs. 41 healthy controls. METHOD: We used clinical methods, instrumental and neuroimmaging procedures, risk factors examination, total plasma homocysteine measurements and other laboratory and statistical modelling techniques. RESULTS: IS patients and healthy controls were similar not only for matching variables, but also for smoking, main vitamin status, serum creatinine and lipid profile. Patients with IS, however, had lower vitamin B6 levels and higher THCY, fibrinogen and triglycerides (TGL). At multivariate stepwise logistic regression only increased THCY and TGL were significantly and independently associated with the risk for stroke (72 percent model accuracy, p model=0.001). An increase of THCY with 1.0 æmol/L was associated with 22 percent higher risk of ischaemic stroke [adjusted OR=1.22 (95 percentCI 1.03?1.44)]. In this way, novel lower cut-off value for HCY of 11.58 æmol/L in younger patients has been revealed (ROC AUC= 0.67, 95CI percent 0.55-0.78, p=0.009). CONCLUSION: The new THCY cut-off clearly discriminated between absence and presence of IS (sensitivity>63 percent, specificity>68 percent) irrespectively of age and gender and may be applied to better evaluate and more precisely define, as earlier as possible, the young patients at increased IS risk.
OBJETIVO: Hiperhomocisteinemia tem sido postulada como um dos fatores de risco na patogênese do acidente vascular cerebral isquêmico (AVCI). Todavia, em adultos jovens existe a possibilidade de aumento significativo de risco de AVCI devido a aumento "normal" da homocisteinemia, "oculta" (patologicamente adormecida) dentro de uma variação definida como normal. Neste trabalho foi investigado um modelo post-hoc de dosagem de homocisteina no plasma (HC) em pacientes jovens com AVCI agudo pareados por gênero e idade. Foi avaliado também relações entre HC e prevalência de outros fatores de risco para AVCI em 41 pacientes e 41 controles normais. MÉTODO: Foi utilizado exame clínico, procedimentos instrumentais e de neuroimagem, exame de fatores de risco, dosagem da homocisteína no plasma, outros exames laboratoriais e análise estatística. RESULTADOS: Não foram encontradas diferenças quanto a presença de fumantes, dosagem de vitaminas, creatinina sérica e perfil lipídico entre os pacientes com AVCI e os controles normais. Todavia os pacientes com AVCI apresentaram diminuição de níveis de vitamina B6 e aumento de homocisteína, fibrinogênio e trigliceridios. A análise multivariada de regressão logística mostrou diferenças significativas apenas para HC e trigliceridios independentemente associadas para fatores de risco para AVCI (72 por cento acuracia, p= 0,001). Um aumento de homocisteína de 1,0 æmol/L estava associado com aumento de 22 por cento de risco de AVCI [OR=1,22 (95 por centoIC 1,03-1,44)]. Foi evidenciado portanto um novo valor de cut-off para HC de 11,58 æmol/L em pacientes jovens com AVCI (ROC auc=0,67, 95 por cento IC 0,55-0,78, p= 0,009). CONCLUSÃO: Este novo valor de cut-offpara a homocisteína discrimina claramente a ausência ou presença de AVCI (sensibilidade >63 por cento, especificidade >68 por cento) independente do gênero ou idade e deve ser aplicado para uma melhor avaliação precoce de pacientes jovens com risco de AVCI.