Effects of variations in meteorological factors on daily hospital visits for asthma: A time-series study.

Few studies have explored the relationships between meteorological factors and asthma. This study explored the associations between daily variations in meteorological factors and hospital visits for asthma among different ages, genders, and asthma subtypes in Shenyang, China. A distributed lag non-linear model with Poisson regression was used; confounding factors included day of the week, holidays, and seasonal patterns, and long-term trends and air pollutants were adjusted using natural cubic splines. The meteorological factor with the largest cumulative effect was barometric pressure, which increased the risk of hospital visits for adult asthma (relative risk [RR] = 2.414), followed by maximum wind speed, which increased hospital visits for asthma for children aged 0-5 years old (RR = 1.47), and pressure, which increased hospital visits for bronchial asthma (RR = 1.298). Meteorological factors showed stronger associations with asthma than air pollutants. Further research should focus more on the effects of meteorological factors on asthma.