Genomic Ancestry, Self-Rated Health and Its Association with Mortality in an Admixed Population: 10 Year Follow-Up of the Bambui-Epigen (Brazil) Cohort Study of Ageing

Mutation profiling of cancer drivers in Brazilian colorectal cancer

The molecular basis of colorectal cancer (CRC) can guide patient prognosis and therapy. In Brazil, knowledge on the CRC mutation landscape is limited. Here, we investigated the mutation profile of 150 cancer-related genes by next-generation sequencing and associated with microsatellite instability (MSI) and genetic ancestry in a series of 91 Brazilian CRC patients. Driver mutations were found in the APC (71.4%), TP53 (56.0%), KRAS (52.7%), PIK3CA (15.4%) and FBXW7 (10.9%) genes. Overall, genes in the MAPK/ERK, PIK3/AKT, NOTCH and receptor tyrosine kinase signaling pathways were mutated in 68.0%, 23.1%, 16.5%, and 15.3% of patients, respectively. MSI was found in 13.3% of tumors, most of which were proximal (52.4%, P< 0.001) and had a high mutation burden. European genetic ancestry was predominant (median of 83.1%), followed by Native American (4.1%), Asian (3.4%) and African (3.2%). NF1 and BRAF mutations were associated with African ancestry, while TP53 and PIK3CA mutations were inversely correlated with Native American ancestry. Our study suggests that Brazilian CRC patients exhibit a mutation profile similar to other populations and identify the most frequently mutated genes, which could be useful in future target therapies and molecular cancer screening strategies.

Mutational profile of Brazilian lung adenocarcinoma unveils association of EGFR mutations with high Asian ancestry and independent prognostic role of KRAS mutations

Lung cancer is the deadliest cancer worldwide. The mutational frequency of EGFR and KRAS genes in lung adenocarcinoma varies worldwide per ethnicity and smoking. The impact of EGFR and KRAS mutations in Brazilian lung cancer remains poorly explored. Thus, we investigated the frequency of EGFR and KRAS mutations in a large Brazilian series of lung adenocarcinoma together with patients’ genetic ancestry, clinicopathological and sociodemographic characteristics. The mutational frequency of EGFR was 22.7% and KRAS was 20.4%. The average ancestry proportions were 73.1% for EUR, 13.1% for AFR, 6.5% for AME and 7.3% for ASN. EGFR mutations were independently associated with never-smokers, high-Asian ancestry, and better performance status. KRAS mutations were independently associated with tobacco exposure and non-Asian ancestry. EGFR-exon 20 mutations were associated with worse outcome. The Cox regression model indicated a worse outcome for patients whose were older at diagnosis (>61 y), solid histological subtype, loss of weight (>10%), worse performance status (≥2), and presence of KRAS mutations and EGFR mutational status in TKi non-treated patients. In conclusion, we assessed the clinicopathological and ethnic impact of EGFR and KRAS mutations in the largest series reported of Brazilian lung adenocarcinomas. These findings can support future clinical strategies for Brazilian lung cancer patients.

Increasing educational inequalities in self-rated health in Brazil, 1998-2013

The objectives of this study are to analyze the associations between educational levels and poor self-rated health (SRH) among adults in Brazil and to assess trends in the prevalence of poor self-rated health across educational groups between 1998 and 2013. Individual-level data came from the 1998, 2003 and 2008 Brazilian National Household Survey and the 2013 National Health Survey. We estimate prevalence rates of poor SRH by education. Using multivariable regressions, we assess the associations between educational levels and poor self-rated health. We use these regressions to predict the estimated ratios between the prevalence rates of those in low vs. high education in order to assess if relative changes in poor SRH have narrowed over time. Finally, we tested for statistically significant time trends in adult chronic disease inequalities by education. Results indicate a clear educational gradient in poor SRH. Prevalence ratios show that Brazilian adults with no education have levels of poor SRH that are 7 to 9 times higher than those with some college or more. The difference between those with lowest and highest education increased from 1998 to 2013. Compared to those with no education, there were increases in the prevalence of poor SRH among those with primary and secondary incomplete as well as among those with secondary complete in 2008 and 2013. In conclusion, there is a positive association between poor SRH and low education. Brazil has many social and geographic inequalities in health. Even though educational levels are increasing, there is no improvement in the general subjective health of Brazilians. Health inequalities by race and region highlight the need to improve the health of socially disadvantaged groups in Brazil. Addressing chronic conditions and mental health is needed to improve self-perceptions of health in Brazil as well.

Does ancestry influence health-related quality of life in type 1 diabetes patients? A nationwide study in Brazil

AIMS

The aim of the present study was to evaluate the relationship between self-reported color/race and genomic ancestry with HRQoL of patients with type 1 diabetes in a highly admixed population.

METHODS

This was a nationwide, cross-sectional study conducted with 1760 patients with type 1 diabetes from 2011 to 2014 at public clinics in all five Brazilian geographical regions. Information on HRQoL was obtained from two self-completed questionnaires: Short Form-6 Dimensions (SF-6D) and EuroQol-5 Dimensions (EQ-5D) with a visual analogue scale (EQ-VAS). Genomic ancestry was assessed using a Multiplex PCR methodology. Utility scores generated from the questionnaires were analyzed with multivariate logistic regression models.

RESULTS

We included 1698 patients. Those patients who self-reported as black had lower EQ-VAS scores compared to the patients who self-reported as white (67.46 ± 18.45; 72.37 ± 16.44, respectively, p = 0.02). In a linear regression model, each 1% increase in African ancestry resulted in a 9.5 point decrease in EQ-VAS score (p < 0.001). In a multivariate logistic regression, after adjusting for demographic, socioeconomic status and diabetes-related variables, African ancestry remained associated with lower EQ-VAS scores.

CONCLUSION

A higher level of African ancestry implicates on lower quality of life even after adjustments for sociodemographic and diabetes-related data. Gender, physical activity and diabetes-related microvascular complications were strongly associated with low HRQoL in all three questionnaires used. This fact highlights the importance of social aspects when assessing quality of life, as well as the need for regular practice of physical activity and prevention of chronic complications to improve patients' quality of life.

Immune senescence and biomarkers profile of Bambuí aged population-based cohort

During immunosenescence many proinflammatory markers such as cytokines and chemokines are increased. This process called by Franceschi and colleagues as inflammaging is associated with chronic inflammation and the ethiology and pathophysiolgy of many ageing diseases as Alzheimer's and atherosclerosis. The knowledge of immune profile during ageing may provide some interventions that would improve the immune function in elderly and quality of life for old people. However, the identification of a group of potential biomarkers to monitor the ageing process is very difficult. In addition, most of the evidence evaluating immune biomarkers profile is based on data from older Caucasian adults. To our knowledge, no previous Latin American old population-based cohort has evaluated immunological parameters along the ageing process. The present work evaluated CXCL8, CXCL9, CXCL10, CCL2, CCL5, IL-1, IL-6, IL-12, TNF and IL-10 serum levels in 1494 older adults aged 60 to 95 from a population based ageing cohort in Brazil. Our data suggest that there is an increased positive predicted probability of participants to be a high producer of IL-6, CXCL8 and CXCL9. Moreover, results did not differ between men and women, except for CXCL10 that increased only in men. Results were not different in the adjusted model by many potential confounders, including African genomic ancestry. Together, these findings add novel insights about the immunologic aspects of ageing supported by a large population-based cohort study that provides evidences that corroborate with the inflammaging proposal and subsidize the establishment of biomarkers for monitoring the health status of aged population.

Social capital, income inequality and the social gradient in self-rated health in Latin America: A fixed effects analysis

Latin America is the most unequal region in the world. The current sustainable development agenda increased attention to health inequity and its determinants in the region. Our aim is to investigate the social gradient in health in Latin America and assess the effects of social capital and income inequality on it. We used cross-sectional data from the World Values Survey and the World Bank. Our sample included 10,426 respondents in eight Latin American countries. Self-rated health was used as the outcome. Education level was the socioeconomic position indicator. We measured social capital by associational membership, civic participation, generalized trust, and neighborhood trust indicators at both individual and country levels. Income inequality was operationalized using the Gini index at country-level. We employed fixed effects logistic regressions and cross-level interactions to assess the impact of social capital and income inequality on the heath gradient, controlling for country heterogeneity. Education level was independently associated with self-rated health, representing a clear social gradient in health, favoring individuals in higher socioeconomic positions. Generalized and neighborhood trust at country-level moderated the effect on the association between socioeconomic position and health, yet favoring individuals in lower socioeconomic positions, especially in lower inequality countries, despite their lower individual social capital. Our findings suggest that collective rather than individual social capital can impact the social gradient in health in Latin America, explaining health inequalities.

The role of gender in the association between self-rated health and mortality among older adults in Santiago, Chile: A cohort study

Background

Previous studies on the role of gender in the association between self-rated health and mortality have shown contrasting results. This study was aimed to determine the importance of gender in the association between self-rated health and mortality among older people in Santiago, Chile.

Methods

A 10 year follow-up of 1066 people aged 60 or more, from the Chilean cohort of the Study of Health, Ageing and Well-Being. Self-rated health was assessed in face to face interviews through a single general question, along with socio-demographic and health status information. Cox proportional hazards and flexible parametric models for survival analyses were employed.

Results

By the end of follow-up, 30.7% of women and 39.4% of men died. Adjusted hazard ratio of poor self-rated health, compared to good self-rated health, was 1.92(95% CI 1.29–2.86). In models stratified by gender, an increased risk of mortality was observed among women who rated their health as poor (HR = 2.21, 95% CI 1.43–3.40), but not among men (HR = 1.04, 95% CI 0.58–1.86). Age was associated with mortality in both groups; for men, functional limitation and underweight were also risk factors and obesity was a protective factor.

Conclusions

Compared to older women who rated their health as good, older women who rated their health as poor had a 2 fold increased risk of mortality over the subsequent 10 years. These findings stress the importance of considering a gender perspective into health programmes, including those focused on older people, in order to address the different elements that increase, on the long run, the risk of dying among older women and men.

Surnames and ancestry in Brazil

This paper presents a method for classifying the ancestry of Brazilian surnames based on historical sources. The information obtained forms the basis for applying fuzzy matching and machine learning classification algorithms to more than 46 million workers in 5 categories: Iberian, Italian, Japanese, German and East European. The vast majority (96.7%) of the single surnames were identified using a fuzzy matching and the rest using a method proposed by Cavnar and Trenkle (1994). A comparison of the results of the procedures with data on foreigners in the 1920 Census and with the geographic distribution of non-Iberian surnames underscores the accuracy of the procedure. The study shows that surname ancestry is associated with significant differences in wages and schooling.

The Sangre Por Salud Biobank: Facilitating Genetic Research in an Underrepresented Latino Community

BACKGROUND/AIMS

The Sangre Por Salud (Blood for Health; SPS) Biobank was created for the purpose of expanding precision medicine research to include underrepresented Latino patients. It is the result of a unique collaboration between Mayo Clinic and Mountain Park Health Center, a federally qualified community health center in Phoenix, Arizona. This report describes the rationale, development, implementation, and characteristics of the SPS Biobank.

METHODS

Latino adults (ages 18-85 years) who were active patients within Mountain Park Health Center's internal medicine practice in Phoenix, Ariz., and had no history of diabetes were eligible. Participants provided a personal and family history of chronic disease, completed a sociodemographic, psychosocial, and behavioral questionnaire, underwent a comprehensive cardiometabolic risk assessment (anthropometrics, blood pressure and labs), and provided blood samples for banking. Laboratory results of cardiometabolic testing were returned to the participants and their providers through the electronic health record.

RESULTS

During the first 2 years of recruitment into the SPS Biobank, 2,335 patients were approached and 1,432 (61.3%) consented to participate; 1,354 (94.5%) ultimately completed all requisite questionnaires and medical evaluations. The cohort is primarily Spanish-speaking (72.9%), female (73.3%), with a mean age of 41.3 ± 12.5 years. Most participants were born outside of the US (77.9%) and do not have health insurance (77.5%). The prevalence of overweight (35.5%) and obesity (45.0%) was high, as was previously unidentified prediabetes (55.9%), type 2 diabetes (7.4%), prehypertension (46.8%), and hypertension (16.2%). The majority of participants rated their health as good to excellent (72.1%) and, as a whole, described their overall quality of life as high (7.9/10).

CONCLUSION

Collaborative efforts such as the SPS Biobank are critical for ensuring that underrepresented minority populations are included in precision medicine initiatives and biomedical research that seeks to improve human health and reduce the burdens of disease.

Genomic African and Native American Ancestry and Chagas Disease: The Bambui (Brazil) Epigen Cohort Study of Aging

BACKGROUND

The influence of genetic ancestry on Trypanosoma cruzi infection and Chagas disease outcomes is unknown.

METHODOLOGY/PRINCIPAL FINDINGS

We used 370,539 Single Nucleotide Polymorphisms (SNPs) to examine the association between individual proportions of African, European and Native American genomic ancestry with T. cruzi infection and related outcomes in 1,341 participants (aged ≥ 60 years) of the Bambui (Brazil) population-based cohort study of aging. Potential confounding variables included sociodemographic characteristics and an array of health measures. The prevalence of T. cruzi infection was 37.5% and 56.3% of those infected had a major ECG abnormality. Baseline T. cruzi infection was correlated with higher levels of African and Native American ancestry, which in turn were strongly associated with poor socioeconomic circumstances. Cardiomyopathy in infected persons was not significantly associated with African or Native American ancestry levels. Infected persons with a major ECG abnormality were at increased risk of 15-year mortality relative to their counterparts with no such abnormalities (adjusted hazard ratio = 1.80; 95% 1.41, 2.32). African and Native American ancestry levels had no significant effect modifying this association.

CONCLUSIONS/SIGNIFICANCE

Our findings indicate that African and Native American ancestry have no influence on the presence of major ECG abnormalities and had no influence on the ability of an ECG abnormality to predict mortality in older people infected with T. cruzi. In contrast, our results revealed a strong and independent association between prevalent T. cruzi infection and higher levels of African and Native American ancestry. Whether this association is a consequence of genetic background or differential exposure to infection remains to be determined.