Is vigorous-intensity physical activity required for improving bone mass in adolescence? Findings from a Brazilian birth cohort.

UNLABELLED: The association between moderate and vigorous physical activity throughout adolescence and areal bone density (aBMD) at 18 years of age was evaluated. Vigorous-intensity physical activity at 11, 15, and 18 years was associated with aBMD in early adulthood, especially in boys. Cross-sectional analyses showed a positive association between moderate physical activity and aBMD. INTRODUCTION: To evaluate independent associations of moderate and vigorous physical activity (MPA, VPA) across adolescence with areal bone mineral density (aBMD). METHODS: Physical activity (PA) was assessed at 11, 15, and 18 years of age by self-report and at 18 years by accelerometry in the 1993 Pelotas Birth Cohort Study. Time spent in MPA and VPA was determined using metabolic equivalents and specific cutoffs based on raw acceleration. Lumbar spine and femoral neck aBMD were measured by DXA at 18 years. Statistical analyses evaluated the association of MPA and VPA with aBMD, after adjusting for skin color, asset index, current height and age at menarche, and peak strain score (based on ground reaction forces of PA). RESULTS: Lumbar spine and femoral neck aBMD were available for 3947 (49.9% of boys) and 3960 (49.6% of boys) individuals, respectively. Time spent in MPA at 11 and 15 years was not associated with aBMD. VPA at all time points was positively related to both lumbar spine and femoral neck aBMD in boys. Results were consistent for objectively measured VPA. Girls who achieved 75+ minutes/week of VPA in at least two follow-ups showed higher aBMD at 18 years of age. Boys who reached 75+ minutes/week of VPA at all follow-ups had on average 0.117 g/cm2 (95% CI: 0.090; 0.144) higher femoral neck aBMD than those who never achieved this threshold. CONCLUSIONS: Self-reported VPA but not MPA throughout adolescence was associated with aBMD. Recommendation for PA in young people should consider the importance of VPA.Authors also acknowledge the MRC Epidemiology PA Programme for assisting with analyses and support of activity monitors funding bodies Medical Research Council and Research Council of Norway

Characterisation of pulmonary function trajectories: results from a Brazilian cohort.

Background: Pulmonary function (PF) trajectories are determined by different exposures throughout the life course. The aim of this study was to investigate characteristics related to PF trajectories from 15 to 22 years in a Brazilian cohort. Methods: A birth cohort study (1993 Pelotas Birth Cohort) was conducted with spirometry at 15, 18 and 22 years. PF trajectories were built based on z-score of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and their ratio using a group-based trajectory model. Associations with exposures reported from perinatal to 22 years were described. Results: Three trajectories, low (LT), average (AT) and high (HT) were identified in 2917 individuals. Wealthiest individuals belonged to the HT of FEV1 (p=0.023). Lower maternal pregestational body mass index (BMI) (22.4±0.2; p<0.001 and 22.1±0.14; p<0.001) and lower birth weight (3164.8±25.4; p=0.029 and 3132.3±19.4; p=0.005) were related to the LT of FEV1 and FVC. Mother's smoking exposure during pregnancy (37.7%; p=0.002), active smoking at ages 18 and 22 years (20.1% and 25.8%; p<0.001) and family history of asthma (44.8%; p<0.001) were related to the LT of FEV1/FVC. Wheezing, asthma and hospitalisations due to respiratory diseases in childhood were related to the LT of both FEV1 and FEV1/FVC. Higher BMIs were related to the HT of FEV1 and FVC at all ages. Conclusions: PF trajectories were mainly related to income, pregestational BMI, birth weight, hospitalisation due to respiratory diseases in childhood, participant's BMI, report of wheezing, medical diagnosis and family history of asthma, gestational exposure to tobacco and current smoking status in adolescence and young adult age

Distinct variation in vector competence among nine field populations of Aedes aegypti from a Brazilian dengue-endemic risk city

Background: In Brazil, dengue epidemics erupt sporadically throughout the country and it is unclear if outbreaks may initiate a sustainable transmission cycle. There are few studies evaluating the ability of Brazilian Aedes aegypti populations to transmit dengue virus (DENV). The aim of this study was to compare DENV susceptibility of field-captured Ae. aegypti populations from nine distinct geographic areas of the city of Belo Horizonte in 2009 and 2011. Infection Rate (IR), Vector Competence (VC) and Disseminated Infection Rate (DIR) were determined. Methods: Aedes aegypti eggs from each region were collected and reared separately in an insectary. Adult females were experimentally infected with DENV-2 and the virus was detected by qPCR in body and head samples. Data were analyzed with the Statistical Package for the Social Sciences version 17. Results: IR varied from 40.0% to 82.5% in 2009 and 60.0% to 100.0% in 2011. VC ranged from 25.0% to 77.5% in 2009 and 25.0% to 80.0% in 2011. DIR oscillated from 68.7% to 100.0% in 2009 and 38.4% to 86.8 in 2011. When the results were evaluated by a logistic model using IR as covariate, North, Barreiro, South-Central and Venda Nova showed the strongest association in 2009. In 2011, a similar association was observed for South-Central, Venda Nova, West and Northeast regions. Using VC as covariate, South-Central and Venda Nova showed the most relevant association in 2009. In 2011, South-Central, Venda Nova and Barreiro presented the greatest revelation associations. When DIR data were analyzed by logistic regression models, Pampulha, South-Central, Venda Nova, West, Northeast and East (2009) as well as South-Central, Venda Nova and West (2011) were the districts showing the strongest associations. Conclusions: We conclude that Ae. aegypti populations from Belo Horizonte exhibit wide variation in vector competence to transmit dengue. Therefore, vector control strategies should be adapted to the available data for each region. Further analysis should be conducted to better understand the reasons for this large variability in vector competence and how these parameters correlate with epidemiological findings in subsequent years

INTERPRETANDO O LÍQUOR – COMO DADOS EPIDEMIOLÓGICOS PODEM AJUDAR NO RACIOCÍNIO CLÍNICO

Introdução: A meningite bacteriana sofreu grandes mudanças epidemiológicas após a introdução dos antibióticos e vacinas, passando de uma condição letal para tratável e prevenível. Compreender essas mudanças no perfil epidemiológico em nível local permitem planejar estratégias de terapia empírica. As alterações de líquor possuem papel fundamental nessa avaliação. Metodologia: Foi realizado um estudo transversal dos casos notificados de meningite entre janeiro de 2010 e junho de 2015 no Complexo Hospital de Clínicas – Universidade Federal do Paraná. Foram analisados a celularidade e citologia do líquor e os agentes etiológicos. Para as etiologias bacterianas, foi avaliado dados epidemiológicos. Resultados: Foram notificados 504 casos de meningite no período avaliado. A meningite asséptica foi a classificação epidemiológica mais comum. As meningites bacterianas com confirmação etiológica causadas por Neisseria meningitidis, Streptococcus pneumoniae ou Haemophilus influenzae ocorreram em 8,7% dos casos notificados, sendo que 30% delas ocorreram em menores de 1 ano. A N. meningitidis correspondeu a 61% desses casos, enquanto que S. pneumoniae a 34%. As meningites neutrofílicas com mais de 75% de neutrófilos são causadas por tais bactérias em mais da metade (53%). A meningite asséptica é a segunda principal etiologia (20%) seguida de perto pela meningite tuberculosa (17%). Os casos de meningite meningocócica se concentram em crianças até 1 ano (56% dos casos), a meningite pneumocócica se concentra nos adultos entre 18 e 50 anos (46%) e idosos (27%). Conclusões: O conhecimento da epidemiologia local através da interpretação do líquor, somada à avaliação da faixa etária são importantes aliados da avaliação clínica para determinação do agente etiológico mais provável e podem ajudar na decisão terapêutica