Validation of the Modified Shuttle Test to Predict Peak Oxygen Uptake in Youth Asthma Patients Under Regular Treatment

Background: Oxygen uptake (VO2) evaluations by cardiopulmonary exercise test is expensive and time-consuming. Estimating VO2 based on a field test would be an alternative.Objective: To develop and validate an equation to predict VO2peak based on the modified shuttle test (MST).Methods: Cross sectional study, with 97 children and adolescents with asthma. Participants were divided in two groups: the equation group (EG), to construct the equation model of VO2peak, and the cross-validation group (VG). Each subject performed the MST twice using a portable gas analyzer. The peak VO2peak during MST was used in the equation model. The patients’ height, weight, gender, and distance walked (DW) during MST were tested as independent variables.Results: The final model [-0.457 + (gender × 0.139) + (weight × 0.025) + (DW × 0.002)] explained 87% of VO2peak variation. The VO2peak predicted was similar to VO2peak measured by gas analyzer (1.9 ± 0.5 L/min and 2.0 ± 0.5 L/min, respectively) (p = 0.67), and presented significant ICC 0.91 (IC95% 0.77 to 0.96); p < 0.001. The Bland–Altman analysis showed low bias (-0.15 L/min) and limits of agreement (-0.65 to 0.35 L/min). There was no difference in DW between EG (760 ± 209 m) and VG (731 ± 180 m), p = 0.51.Conclusion: The developed equation adequately predicts VO2peak in pediatric patients with asthma

Validation of the modified shuttle test to predict peak oxygen uptake in youth asthma patients under regular treatment

Background: Oxygen uptake (VO2) evaluations by cardiopulmonary exercise test is expensive and time-consuming. Estimating VO2 based on a field test would be an alternative. Objective: To develop and validate an equation to predict VO2peak based on the modified shuttle test (MST). Methods: Cross sectional study, with 97 children and adolescents with asthma. Participants were divided in two groups: the equation group (EG), to construct the equation model of VO2peak, and the cross-validation group (VG). Each subject performed the MST twice using a portable gas analyzer. The peak VO2peak during MST was used in the equation model. The patients' height, weight, gender, and distance walked (DW) during MST were tested as independent variables. Results: The final model [-0.457 + (gender × 0.139) + (weight × 0.025) + (DW × 0.002)] explained 87% of VO2peak variation. The VO2peak predicted was similar to VO2peak measured by gas analyzer (1.9 ± 0.5 L/min and 2.0 ± 0.5 L/min, respectively) (p = 0.67), and presented significant ICC 0.91 (IC95% 0.77 to 0.96); p < 0.001. The Bland-Altman analysis showed low bias (-0.15 L/min) and limits of agreement (-0.65 to 0.35 L/min). There was no difference in DW between EG (760 ± 209 m) and VG (731 ± 180 m), p = 0.51. Conclusion: The developed equation adequately predicts VO2peak in pediatric patients with asthma

The neuropathological landscape of Hispanic and non-Hispanic White decedents with Alzheimer disease

Despite the increasing demographic diversity of the United States' aging population, there remain significant gaps in post-mortem research investigating the ethnoracial heterogeneity in the neuropathological landscape of Alzheimer Disease (AD). Most autopsy-based studies have focused on cohorts of non-Hispanic White decedents (NHWD), with few studies including Hispanic decedents (HD). We aimed to characterize the neuropathologic landscape of AD in NHWD (n = 185) and HD (n = 92) evaluated in research programs across three institutions: University of California San Diego, University of California Davis, and Columbia University. Only persons with a neuropathologic diagnosis of intermediate/high AD determined by NIA Reagan and/or NIA-AA criteria were included. A frequency-balanced random sample without replacement was drawn from the NHWD group using a 2:1 age and sex matching scheme with HD. Four brain areas were evaluated: posterior hippocampus, frontal, temporal, and parietal cortices. Sections were stained with antibodies against Aβ (4G8) and phosphorylated tau (AT8). We compared the distribution and semi-quantitative densities for neurofibrillary tangles (NFTs), neuropil threads, core, diffuse, and neuritic plaques. All evaluations were conducted by an expert blinded to demographics and group status. Wilcoxon's two-sample test revealed higher levels of neuritic plaques in the frontal cortex (p = 0.02) and neuropil threads (p = 0.02) in HD, and higher levels of cored plaques in the temporal cortex in NHWD (p = 0.02). Results from ordinal logistic regression controlling for age, sex, and site of origin were similar. In other evaluated brain regions, semi-quantitative scores of plaques, tangles, and threads did not differ statistically between groups. Our results demonstrate HD may be disproportionately burdened by AD-related pathologies in select anatomic regions, particularly tau deposits. Further research is warranted to understand the contributions of demographic, genetic, and environmental factors to heterogeneous pathological presentations

Data from the European registry for patients with McArdle disease and other muscle glycogenoses (EUROMAC)

The European registry for patients with McArdle disease and other muscle glycogenoses (EUROMAC) was launched to register rare muscle glycogenoses in Europe, to facilitate recruitment for research trials and to learn about the phenotypes and disseminate knowledge about the diseases through workshops and websites. A network of twenty full and collaborating partners from eight European countries and the US contributed data on rare muscle glycogenosis in the EUROMAC registry. After approximately 3 years of data collection, the data in the registry was analysed. Of 282 patients with confirmed diagnoses of muscle glycogenosis, 269 had McArdle disease. New phenotypic features of McArdle disease were suggested, including a higher frequency (51.4%) of fixed weakness than reported before, normal CK values in a minority of patients (6.8%), ptosis in 8 patients, body mass index above background population and number of comorbidities with a higher frequency than in the background population (hypothyroidism, coronary heart disease). The EUROMAC project and registry have provided insight into new phenotypic features of McArdle disease and the variety of co-comorbidities affecting people with McArdle disease. This should lead to better management of these disorders in the future, including controlling weight, and preventive screening for thyroid and coronary artery diseases, as well as physical examination with attention on occurrence of ptosis and fixed muscle weakness. Normal serum creatine kinase in a minority of patients stresses the need to not discard a diagnosis of McArdle disease even though creatine kinase is normal and episodes of myoglobinuria are absen