Impact on mortality of being seropositive for hepatitis C virus antibodies among blood donors in Brazil: A twenty-year study.

INTRODUCTION: Hepatitis C virus (HCV) infection is a major health problem associated with considerable risk of mortality in different regions of the world. The purpose of this study was to investigate the contribution of HCV infection on all-cause and liver-related mortality, in a large cohort of blood donors in Brazil. METHODS: This is a retrospective cohort study of blood donors from 1994 to 2013, at Fundação Pró-Sangue-Hemocentro de São Paulo (FPS). This cohort included 2,892 and 5,784 HCV antibody seropositive and seronegative donors, respectively. Records from the FPS database and the Mortality Information System (SIM: a national database in Brazil) were linked through a probabilistic record linkage (RL). Mortality outcomes were defined based on ICD-10 (10th International Statistical Classification of Diseases and Related Health Problems) codes listed as the cause of death on the death certificate. Hazard ratios (HRs) were estimated for outcomes using Cox multiple regression models. RESULTS: When all causes of death were considered, RL identified 209 deaths (7.2%) among seropositive blood donors and 190 (3.3%) among seronegative blood donors. Donors seropositive for HCV infection had a 2.5 times higher risk of death due to all causes (95% CI: 1.76-2.62; p<0.001). When only liver-related causes of death were considered, RL identified 73 deaths among seropositive blood donors and only 6 among seronegative blood donors. Donors seropositive for HCV infection had a 23.4 times higher risk of death due to liver related causes (95% CI: 10.2-53.9; p<0.001). Donors seropositive for HCV had a 29.5 (95%CI: 3.9-221.7), 2.8 (95% CI: 1.4-5.5) and a 1.9 (95% CI: 1.2-3.0) times higher risk of death due to hepatocellular carcinoma, infection or trauma, respectively, compared to seronegative donors. CONCLUSIONS: All-cause and liver-related mortality rate was increased among blood donors seropositive for HCV compared with the mortality rate among seronegative blood donors. Our data confirms HCV as a relevant cause of death in Brazil and also suggest that interventions directed at following patients even after access to specific drug treatment are urgent and necessary.

Decreased glycolytic metabolism in non-compaction cardiomyopathy by 18F-fluoro-2-deoxyglucose positron emission tomography: new insights into pathophysiological mechanisms and clinical implications.

AIMS: The pathophysiological mechanisms of left ventricular non-compaction cardiomyopathy (LVNC) remain controversial. This study performed combined 18F-fluoro-2-deoxyglucose dynamic positron emission tomography (FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (SPECT) studies to evaluate myocardial glucose metabolism and perfusion in patients with LVNC and their clinical implications. METHODS AND RESULTS: Thirty patients (41 ± 12 years, 53% male) with LVNC, diagnosed by cardiovascular magnetic resonance (CMR) criteria, and eight age-matched healthy controls (42 ± 12 years, 50% male) were prospectively recruited to undergo FDG-PET with measurement of the myocardial glucose uptake rate (MGU) and SPECT to investigate perfusion-metabolism patterns. Patients with LVNC had lower global MGU compared with that in controls (36.9 ± 8.8 vs. 44.6 ± 5.4 µmol/min/100 g, respectively, P = 0.02). Of 17 LV segments, MGU levels were significantly reduced in 8, and also a reduction was observed when compacted segments from LVNC were compared with the segments from control subjects (P < 0.001). Perfusion defects were also found in 15 (50%) patients (45 LV segments: 64.4% match, and 35.6% mismatch perfusion-metabolism pattern). Univariate and multivariate analyses showed that beta-blocker therapy was associated with increased MGU (beta coefficient = 10.1, P = 0.008). Moreover, a gradual increase occurred in MGU across the beta-blocker dose groups (P for trend = 0.01). CONCLUSION: The reduction of MGU documented by FDG-PET in LVNC supports the hypothesis that a cellular metabolic pathway may play a role in the pathophysiology of LVNC. The beneficial effect of beta-blocker mediating myocardial metabolism in the clinical course of LVNC requires further investigation.

Accuracy of probabilistic and deterministic record linkage: the case of tuberculosis.

OBJECTIVE: To analyze the accuracy of deterministic and probabilistic record linkage to identify TB duplicate records, as well as the characteristics of discordant pairs. METHODS: The study analyzed all TB records from 2009 to 2011 in the state of Rio de Janeiro. A deterministic record linkage algorithm was developed using a set of 70 rules, based on the combination of fragments of the key variables with or without modification (Soundex or substring). Each rule was formed by three or more fragments. The probabilistic approach required a cutoff point for the score, above which the links would be automatically classified as belonging to the same individual. The cutoff point was obtained by linkage of the Notifiable Diseases Information System - Tuberculosis database with itself, subsequent manual review and ROC curves and precision-recall. Sensitivity and specificity for accurate analysis were calculated. RESULTS: Accuracy ranged from 87.2% to 95.2% for sensitivity and 99.8% to 99.9% for specificity for probabilistic and deterministic record linkage, respectively. The occurrence of missing values for the key variables and the low percentage of similarity measure for name and date of birth were mainly responsible for the failure to identify records of the same individual with the techniques used. CONCLUSIONS: The two techniques showed a high level of correlation for pair classification. Although deterministic linkage identified more duplicate records than probabilistic linkage, the latter retrieved records not identified by the former. User need and experience should be considered when choosing the best technique to be used. OBJETIVO: Analisar a acurácia das técnicas determinística e probabilística para identificação de registros duplicados de tuberculose, assim como as características dos pares discordantes. MÉTODOS: Foram analisados todos os registros de tuberculose no período de 2009 a 2011 do estado do Rio de Janeiro. Foi desenvolvido algoritmo para relacionamento determinístico, usando conjunto de 70 regras, a partir da combinação de fragmentos das variáveis-chave com ou sem modificações (Soundex ou substring). Cada regra era formada por três ou mais fragmentos. Para a abordagem probabilística, foi necessário estabelecer ponto de corte para o escore, acima do qual os links seriam classificados automaticamente como pertencentes ao mesmo indivíduo. O ponto de corte foi obtido por meio do relacionamento da base de dados Sistema de Informação de Agravos de Notificação - Tuberculose com ela mesma, posterior revisão manual e curvas ROC e precision-recall. Foram calculadas a sensibilidade e especificidade para análise de acurácia. RESULTADOS: A acurácia variou de 87,2% a 95,2% para sensibilidade e 99,8% a 99,9% para especificidade para as técnicas probabilística e determinística, respectivamente. A presença de valores faltantes para as variáveis-chave e o baixo percentual da medida de similaridade para o nome e data de nascimento foram os principais responsáveis pela não identificação dos registros do mesmo indivíduo pelas técnicas utilizadas. CONCLUSÕES: As duas técnicas apresentam alta concordância para a classificação como par. Apesar de a técnica determinística ter identificado mais registros duplicados que a probabilística, a segunda recuperou registros não identificados pela primeira. A necessidade e a experiência do usuário devem ser consideradas para a escolha da técnica a ser utilizada.

Accuracy of probabilistic and deterministic record linkage: the case of tuberculosis / Acurácia das técnicas de relacionamento probabilístico e determinístico: o caso da tuberculose

ABSTRACT OBJECTIVE To analyze the accuracy of deterministic and probabilistic record linkage to identify TB duplicate records, as well as the characteristics of discordant pairs. METHODS The study analyzed all TB records from 2009 to 2011 in the state of Rio de Janeiro. A deterministic record linkage algorithm was developed using a set of 70 rules, based on the combination of fragments of the key variables with or without modification (Soundex or substring). Each rule was formed by three or more fragments. The probabilistic approach required a cutoff point for the score, above which the links would be automatically classified as belonging to the same individual. The cutoff point was obtained by linkage of the Notifiable Diseases Information System - Tuberculosis database with itself, subsequent manual review and ROC curves and precision-recall. Sensitivity and specificity for accurate analysis were calculated. RESULTS Accuracy ranged from 87.2% to 95.2% for sensitivity and 99.8% to 99.9% for specificity for probabilistic and deterministic record linkage, respectively. The occurrence of missing values for the key variables and the low percentage of similarity measure for name and date of birth were mainly responsible for the failure to identify records of the same individual with the techniques used. CONCLUSIONS The two techniques showed a high level of correlation for pair classification. Although deterministic linkage identified more duplicate records than probabilistic linkage, the latter retrieved records not identified by the former. User need and experience should be considered when choosing the best technique to be used.

RESUMO OBJETIVO Analisar a acurácia das técnicas determinística e probabilística para identificação de registros duplicados de tuberculose, assim como as características dos pares discordantes. MÉTODOS Foram analisados todos os registros de tuberculose no período de 2009 a 2011 do estado do Rio de Janeiro. Foi desenvolvido algoritmo para relacionamento determinístico, usando conjunto de 70 regras, a partir da combinação de fragmentos das variáveis-chave com ou sem modificações (Soundex ou substring). Cada regra era formada por três ou mais fragmentos. Para a abordagem probabilística, foi necessário estabelecer ponto de corte para o escore, acima do qual os links seriam classificados automaticamente como pertencentes ao mesmo indivíduo. O ponto de corte foi obtido por meio do relacionamento da base de dados Sistema de Informação de Agravos de Notificação - Tuberculose com ela mesma, posterior revisão manual e curvas ROC e precision-recall. Foram calculadas a sensibilidade e especificidade para análise de acurácia. RESULTADOS A acurácia variou de 87,2% a 95,2% para sensibilidade e 99,8% a 99,9% para especificidade para as técnicas probabilística e determinística, respectivamente. A presença de valores faltantes para as variáveis-chave e o baixo percentual da medida de similaridade para o nome e data de nascimento foram os principais responsáveis pela não identificação dos registros do mesmo indivíduo pelas técnicas utilizadas. CONCLUSÕES As duas técnicas apresentam alta concordância para a classificação como par. Apesar de a técnica determinística ter identificado mais registros duplicados que a probabilística, a segunda recuperou registros não identificados pela primeira. A necessidade e a experiência do usuário devem ser consideradas para a escolha da técnica a ser utilizada.