Evaluation of peak expiratory flow in adolescents and its association with inhalable particulate in a Brazilian medium-sized city

Maximum Expiratory Flow of Children and Adolescents Living at Moderate Altitudes: Proposed Reference Values

(1) Background: Spirometry is useful for diagnosing and monitoring many respiratory diseases. The objectives were: (a) compare maximum expiratory flow (MEF) values with those from international studies, (b) determine if MEF should be evaluated by chronological age and/or maturity, (c) develop reference norms for children, and adolescents. (2) Methods: A cross-sectional study was designed with 3900 subjects ages 6.0 and 17.9 years old. Weight, standing height, sitting height, and MEF were measured. Length of the lower limbs, body mass index (BMI), and age of peak height velocity growth (APHV) were calculated. (3) Results: Values for the curves (p50) for females of all ages from Spain and Italy were higher (92 to 382 (L/min)) than those for females from Arequipa (Peru). Curve values for males from Spain and Italy were greater [70 to 125 (L/min)] than the males studied. MEF values were similar to those of Chilean students ages 6 to 11. However, from 12 to 17 years old, values were lower in males (25 to 55 (L/min)) and in females (23.5 to 90 (L/min)). Correlations between chronological age and MEF in males were from (r = 0.68, R² = 0.39) and in females from (r = 0.46, R² = 0.21). Correlations between maturity (APHV) and MEF for males were from (r = 0.66, R² = 0.44) and for females (r = 0.51, R² = 0.26). Percentiles were calculated for chronological age and APHV. Conclusion: Differences occurred in MEF when compared with other geographical regions of the world. We determined that maturity may be a more effective indicator for analyzing MEF. Reference values were generated using chronological age and maturity.

Air Pollution and Asthma: Mechanisms of Harm and Considerations for Clinical Interventions

There is global concern regarding the harmful impact of polluted air on the respiratory health of patients with asthma. Multiple epidemiologic studies have shown ongoing associations between high levels of air pollution and poor early life lung growth, development of allergic sensitization, development of asthma, airway inflammation, acutely impaired lung function, respiratory tract infections, and asthma exacerbations. However, studies have often yielded inconsistent findings, and not all studies have found significant associations; this may be related to both variations in statistical, measurement, and modeling methodologies between studies as well as differences in the concentrations and composition of air pollution globally. Overall, this variation in findings suggests we still do not fully understand the effects of ambient pollution on the lungs and on the evolution and exacerbation of airway diseases. There is clearly a need to augment epidemiologic studies with experimental studies to clarify the underlying mechanistic basis for the adverse responses reported and to identify the key gaseous and particle-related components within the complex air pollution mixture driving these outcomes. Some progress toward these aims has been made. This article reviews studies providing an improved understanding of causal pathways linking air pollution to asthma development and exacerbation. The article also considers potential strategies to reduce asthma morbidity and mortality through regulation and behavioral/pharmacologic interventions, including a consideration of pollutant avoidance strategies and antioxidant and/or vitamin D supplementation.

Effects of Air Pollution on Human Health and Costs: Current Situation in São Paulo, Brazil

This study focused on verifying whether the emission of air pollutants in São Paulo increases the costs and number of hospitalizations for respiratory diseases in Brazil. Data on pollutant emissions, hospitalizations, and hospital costs were collected from 2008 to 2017 and correlated with air quality standards. The results showed that the concentration of particulate matter increased each year during the study period and was highly correlated with hospitalizations due to respiratory diseases. Ozone (O3) was within the quality standard throughout the study period but registered an increase in the mean and a positive correlation with hospitalizations due to respiratory diseases. The carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen dioxide (NO2) levels were within the quality standards throughout the study period with a decrease in the last years studied, but showed a positive correlation with hospitalizations due to respiratory diseases. The pollutant emissions and hospitalizations due to respiratory diseases had an inverse relationship with the monthly rainfall curve for São Paulo, which indicates that rainfall tended to reduce pollutant emissions and consequently hospitalizations due to inhalation of these pollutants. Because costs are directly associated with hospitalizations, both increased during the study period—302,000 hospitalizations at an average cost of 368 USD resulted in a total cost of 111 million USD. To reduce these costs, Brazil should implement stricter policies to improve the air quality of its major cities and develop a viable alternative to diesel vehicles.