Relation of Change in Weight Status to the Development of Hypertension in Children and Adolescents

Background/Aims: This study examined the association of body mass index (BMI) percentile and change in BMI percentile to change in blood pressure (BP) percentile and development of hypertension in children and adolescents. Methods: This retrospective cohort included 101,725 subjects aged 3–17 years from three health systems across the United States. Height, weight, age, sex and BP measures were extracted from electronic health records, and then age/sex/height-adjusted BP percentiles and BMI percentiles were computed. Mixed linear regression estimated change in systolic BP percentile, and proportional hazards regression was used to estimate risk of incident hypertension associated with BMI percentile and change in BMI percentile. Results: The largest increases in BP percentile were observed among children and adolescents who became obese or maintained obesity. Over a median 3.1-year follow-up, 0.4% of subjects developed hypertension. Obese children aged 3–11 had 3.5-fold increased risk of developing hypertension compared with normal weight. Obese adolescents aged 12–17 had 3.2-fold increased risk of developing hypertension compared with normal weight. Children and adolescents who stayed obese had 5.4- and 4.8-fold increased risk of developing hypertension, respectively, compared with those who maintained a normal weight. Children who became obese and adolescents who became overweight had 2.6- and 2.3-fold increased risk of developing hypertension, respectively. Conclusion: We observed a strong, statistically significant association between increasing BMI percentile and increases in BP percentile, with risk of incident hypertension primarily associated with obesity. The adverse impact of weight gain and obesity in this young cohort over a short period of time underscores the need for effective strategies for prevention of overweight and obesity in youth to slow progression toward diabetes and cardiovascular disease later in life

Coronal Heating as Determined by the Solar Flare Frequency Distribution Obtained by Aggregating Case Studies

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating.Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 7

Book of Abstracts: 2019 Health Equity Summer Research Summit Organized by the Center of Excellence in Health Equity, Training and Research, Baylor College of Medicine, Houston, Texas 77030, USA on June 18th, 2019

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