Potential Determinants of Thyroid Peroxidase Antibodies and Mortality Risk: Results From the ELSA-Brasil Study.

CONTEXT: The presence of thyroid peroxidase antibodies (TPOAbs) may be considered as an indicator of adverse health outcomes. OBJECTIVE: We aimed to investigate the potential determinants of TPOAb levels and to analyze the association between TPOAb titers and the risk of all- and specific-cause mortality. METHODS: Baseline and longitudinal data of 13 187 participants from the ELSA-Brasil Study were analyzed. We investigated the association of TPOAb, detectability, positivity, and persistent positivity with sociodemographic and lifestyle factors using logistic regressions. Cox proportional hazards and Fine-Gray subdistribution hazard regression analyses were used to verify the association of TPOAbs with mortality. RESULTS: The determinants of TPOAb detectability and positivity were younger age, higher body mass index, female sex, and former and current smoking status. Black, mixed, and other self-reported races, intermediate and higher education, and heavy drinking were determinants of detectable and positive TPOAb levels. Female sex, White race, and former smoking were determinants of persistent TPOAb positivity at 2 visits, although only the female sex maintained its association at 3 visits. Moreover, after multivariate adjustment, there were associations between higher levels of TPOAbs and higher risk of cancer-related mortality among men, and TPOAb detectability and mortality by other causes among women. CONCLUSION: Sociodemographic and lifestyle-related factors were determinants of multiple TPOAb categories. TPOAb levels were associated with mortality risk; however, the low mortality rate in this sample might have compromised this finding. We suggest further studies to explore the clinical importance of detectable TPOAb levels, not only its positivity, as a potential marker of inflammation.

Machine learning to predict 30-day quality-adjusted survival in critically ill patients with cancer.

PURPOSE: To develop and compare the predictive performance of machine-learning algorithms to estimate the risk of quality-adjusted life year (QALY) lower than or equal to 30 days (30-day QALY). MATERIAL AND METHODS: Six machine-learning algorithms were applied to predict 30-day QALY for 777 patients admitted in a prospective cohort study conducted in Intensive Care Units (ICUs) of two public Brazilian hospitals specialized in cancer care. The predictors were 37 characteristics collected at ICU admission. Discrimination was evaluated using the area under the receiver operating characteristic (AUROC) curve. Sensitivity, 1-specificity, true/false positive and negative cases were measured for different estimated probability cutoff points (30%, 20% and 10%). Calibration was evaluated with GiViTI calibration belt and test. RESULTS: Except for basic decision trees, the adjusted predictive models were nearly equivalent, presenting good results for discrimination (AUROC curves over 0.80). Artificial neural networks and gradient boosted trees achieved the overall best calibration, implying an accurately predicted probability for 30-day QALY. CONCLUSIONS: Except for basic decision trees, predictive models derived from different machine-learning algorithms discriminated the QALY risk at 30 days well. Regarding calibration, artificial neural network model presented the best ability to estimate 30-day QALY in critically ill oncologic patients admitted to ICUs.

Left ventricular mass in patients with heart failure.

OBJECTIVE: To assess left ventricular mass in patients with heart failure and its correlations with other clinical variables and prognosis. METHODS: The study comprised 587 patients aged from 13.8 years to 68.9 years, 461 (78.5%) being males and 126 (21.5%) females. Left ventricular mass was estimated by using M-mode echocardiography and was indexed by height. RESULTS: The left ventricular mass index ranged from 35.3 g/m to 333.5 g/m and increased with age. The left ventricular mass index was greater in males (mean, 175.7 g/m) than in females (mean, 165.7 g/m). The left ventricular mass index was greater in patients with hypertensive cardiomyopathy (mean of 188.1 g/m), with idiopathic dilated cardiomyopathy (mean, 177.7 g/m) and with cardiomyopathies of other etiologies (mean, 175.1 g/m) than in patients with chagasic (mean, 164.3 g/m) or ischemic (mean, 162 g/m) cardiomyopathy. The left ventricular mass index in patients with heart failure showed a correlation with age, sex, etiology, and left atrial diameter. The correlation with left ventricular ejection fraction was negative: the increase in the left ventricular mass index was associated with a reduction in ejection fraction. The relative risk of death was 1.22 for each 50-g/m increase in the left ventricular mass index. CONCLUSIONS: The estimate of left ventricular mass may contribute to the prognostic assessment of patients with heart failure.

Massa ventricular esquerda em portadores de insuficiência cardíaca / Left ventricular mass in patients with heart failure

OBJETIVO: Avaliar a massa ventricular esquerda em pacientes com insuficiência cardíaca, as correlações com outras variáveis clínicas e com o prognóstico. MÉTODOS: Foram estudados 587 pacientes com idades entre 13,8 anos e 68,9 anos, 461 (78,5 por cento) homens e 126 (21,5 por cento) mulheres. A massa ventricular esquerda foi estimada com o uso do ecocardiograma no modo M e indexada pela altura. RESULTADOS: O índice da massa ventricular esquerda variou de 35,3 g/m a 333,5 g/m e aumentou conforme a idade. O índice da massa ventricular esquerda foi maior nos homens (média 175,7 g/m) do que nas mulheres (média 165,7 g/m). O índice da massa ventricular esquerda foi maior nos portadores de cardiomiopatia hipertensiva (média 188,1 g/m), de cardiomiopatia dilatada idiopática (média 177,7 g/m) e de cardiomiopatias de outras etiologias (média 175,1 g/m) do que nos portadores de cardiomiopatia chagásica (média 164,3 g/m) e isquêmica (média 162 g/m). O índice da massa ventricular esquerda de portadores de insuficiência cardíaca demonstrou associação com a idade, o sexo, a etiologia e o diâmetro do átrio esquerdo. A correlação com a fração de ejeção do ventrículo esquerdo foi negativa - o aumento do índice da massa ventricular esquerda associou-se à redução da fração de ejeção. O risco relativo de óbito foi 1,22 para cada acréscimo de 50 g/m no índice da massa ventricular esquerda. CONCLUSÕES: A estimação da massa ventricular esquerda pode contribuir para a avaliação prognóstica de portadores de insuficiência cardíaca.