Neijens H J
Department of Pediatrics, Erasmus University, The Netherlands.
Lung. 1990;168 Suppl:268-77. doi: 10.1007/BF02718142.
Bronchial hyperresponsiveness (BHR) can be considered as a feature of asthma, although only a loose relationship is present with symptoms and severity of the disease. Epidemiology of BHR may inform about determining factors in BHR and its role as a risk factor. BHR is found already at a young age, mostly diminishes with age, and increases in many asthmatic patients after midlife. Genetic determinants are suggested by familial segregation and twin studies. Allergy, respiratory infections, and cigarette smoking are found to induce increase in BHR and to modify its degree at the long run. The mechanisms in BHR are being unraveled gradually. A chronic inflammation with an important role for eosinophils, mast cells, and others, is thought to modify bronchial mechanisms, such as smooth muscle, epithelium, and autonomic systems. Growing evidence supports that T lymphocytes are implicated and may determine many of the inflammatory cells, such as eosinophils, neutrophils, and mast cells.
支气管高反应性（BHR）可被视为哮喘的一个特征，尽管它与疾病的症状和严重程度之间仅存在一种松散的关系。BHR的流行病学可以为BHR的决定因素及其作为危险因素的作用提供信息。BHR在年轻时就已出现，大多随年龄增长而减轻，并且在许多中年后的哮喘患者中会增加。家族性分离研究和双胞胎研究提示了遗传决定因素。已发现过敏、呼吸道感染和吸烟会导致BHR增加，并从长远来看改变其程度。BHR的机制正在逐步被揭示。一种对嗜酸性粒细胞、肥大细胞及其他细胞起重要作用的慢性炎症，被认为会改变支气管机制，如平滑肌、上皮和自主神经系统。越来越多的证据支持T淋巴细胞参与其中，并可能决定许多炎症细胞，如嗜酸性粒细胞、中性粒细胞和肥大细胞。
