Short-term effects of air pollution on exacerbations of allergic asthma in Užice region, Serbia

Abstract

Introduction: Many time-series studies have shown a positive association between air pollution and asthma exacerbation. However, till now only one study in Serbia has examined this relationship. Aim: To examine the associations between air pollution and asthma emergency department (ED) visits in the Užice region, Serbia. Material and methods: A time-stratified case-crossover design was applied to 424 ED visits for asthma exacerbation that occurred in the Užice region, Serbia, in 2012-2014. Data about ED visits were routinely collected in the Užice Health Centre. The daily average concentrations of particulate matter (PM 2.5 and PM 10), sulphur dioxide (SO 2), nitrogen dioxide (NO 2), and black carbon (BC) were measured by automatic ambient air quality monitoring stations. Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression adjusted for the potential confounding influence of weather variables (temperature, humidity and air pressure). Results: Statistically significant associations were observed between ED visits for asthma and 3-day lagged exposure to BC (OR = 3.23; 95% CI: 1.05-9.95), and between ED visits for asthma with coexisting allergic rhinitis and 0-day lag exposure to NO 2 (OR = 1.57; 95% CI: 0.94-2.65), 2-day lag exposure to SO 2 (OR = 1.97; 95% CI: 1.02-3.80), and 3-day lag exposure to PM 10 (OR = 2.38; 95% CI: 1.17-4.84). Conclusions: Exposure to ambient air pollution in the Užice region increases the risk of ED visits for asthma, particularly during the heating season.

Is short-term and long-term exposure to black carbon associated with cardiovascular and respiratory diseases? A systematic review and meta-analysis based on evidence reliability

“…Of these, 70 fulfilled the inclusion criteria (figure 1). 7 21–26 34–96 Of the 70 included studies, 56 estimated the short-term effects of BC/EC using a time series design or case cross-over design, while 14 studies explored the long-term effects of BC/EC using a cohort design. Thirty-seven of the 70 studies reported morbidity as the outcome variable, 25 studies reported mortality and 8 studies reported both morbidity and mortality.…”

“…The confounding bias and selective reporting were mostly rated as ‘probably low’. However, seven studies were rated as ‘probably high’ risk because not all critical potential confounders were adjusted in the analysis 7 24 26 46 55 74 91. In addition, the majority of the included studies on the exposure assessment were assessed as ‘probably low’ and ‘probably high’, and in some cases studies were rated as ‘high’ risk.…”

Influencia de la contaminación ambiental sobre las agudizaciones del asma bronquial en un área de baja contaminación

“…Tampoco Kovacevic et al, en un estudio desarrollado en Serbia, encontraron una asociación significativa. Estos autores reportaron un valor de OR elevado (1,76), pero al incluir una muestra pequeña de 424 VUA, los intervalos de confianza eran muy amplios 121 .…”

“…VUA: visitas a urgencias por asma; Lag: desfase entre la exposición y la visita a urgencias; IC95%: intervalo de confianza al 95%; MLG: modelo lineal generalizado; CC: casos cruzados; RR: riesgo relativo; OR: Odds ratio *Oredenadas por nivel decreciente de concentración3 , no encontrando una asociación positiva significativa entre el número de VUA y PM10 (asociación negativa: RR <1)120 ; mientras que Kwon et alanalizando 660 VUA en Corea, con un valor medio de PM10 de 48,7 µg/m 3 , tampoco encontraron una relación significativa131 . Kovacevic et al analizó una serie de 424 VUA en Serbia, con un nivel medio de PM10 de 34,2 µg/m 3 , reportando una relación significativa entre el aumento de este contaminante y las VUA solamente en el subgrupo de pacientes con rinitis alérgica, pero no en la población total121 . Con respecto a los meta-análisis, Zheng et al incluyeron 51 publicaciones que analizaban esta relación, encontrando una asociación positiva significativa con un RR de 1,010 por 10 µg/m 3 , mientras que observaron un tamaño de efecto ligeramente menor para el subgrupo de población adulta en los 7 estudios analizados (RR 1,009)115 .…”

“…En el otro extremo, Kovacevic et al reportaron una OR de 1,76 (por 30 µg/m 3 ), pero, aun siendo muy superior, no fue estadísticamente significativa (IC95% 0,74- 4,18). Este hecho podría deberse al reducido número de VUA de su muestra (420 casos)121 . ,019)129 .…”