Asthma is a clinical syndrome that affects all age groups. Asthma prevalence worldwide has seen a rapid increase in the latter part of the last century. Recent data has shown that asthma prevalence has plateaued and even decreased in some areas of the world, despite continuing to increase in other areas of the world. Many risk factors have been associated with asthma and the differences in distributions of these risk factors may explain the differences in prevalence. This article will review recent trends in the prevalence of asthma and recent studies that investigate risk factors of asthma.

中文翻译：

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哮喘的流行病学和危险因素。

哮喘是一种影响所有年龄段的临床综合征。在上个世纪后期，全世界的哮喘患病率迅速增加。最新数据表明，尽管世界其他地区的哮喘流行率持续上升，但在世界某些地区哮喘的发病率已经达到平稳甚至下降的水平。许多危险因素与哮喘有关，这些危险因素分布的差异可以解释患病率的差异。本文将回顾哮喘患病率的最新趋势以及调查哮喘危险因素的最新研究。