Soutar A, Harker C, Seaton A, Packe G
Department of Environmental and Occupational Medicine, University Medical School, Foresterhill, Aberdeen.
Occup Environ Med. 1995 Sep;52(9):575-80. doi: 10.1136/oem.52.9.575.
To investigate atopy and changes in symptoms, peak flow rate, and bronchial reactivity in people complaining of symptoms during the oilseed rape flowering season.
37 people who had given positive answers to questions about the presence of symptoms in relation to the flowering season of oilseed rape and 24 controls with no such symptoms were studied, although not all took part in all parts of the study. All had been previously identified in a cross sectional survey of a random sample of a rural population. Atopy was assessed by means of skin prick tests, total immunoglobulin E (IgE), and radioallergosorbent test (RAST) assays. Bronchial reactivity (PC20) was measured by histamine challenge. Total IgE and bronchial reactivity were measured both before and during the oilseed rape flowering season. Day to day changes were monitored by subjects who kept a record of their symptoms and peak flow morning and evening, starting before the flowering season and continuing during it and into the grass pollen season.
Only two cases, of 23 tested, showed evidence of allergy to oilseed rape and only 10 of 23 tested, including these two, were atopic. Eye, nasal, and headache symptoms increased in the season in cases, which validated the questionnaire used in the previous cross sectional survey. 12 of 16 cases tested and seven of 15 controls showed a seasonal fall in PC20; the fall in the cases was significantly greater than in the controls. Peak flow charts showed no evidence of fall or of increased variability during the season.
People who complained of symptoms in relation to the flowering of oilseed rape were rarely allergic to the plant and fewer than half were atopic. Nevertheless, they usually showed increased bronchial reactivity during the season, which may have been due in some cases to other allergens but in others to non-specific irritant effects of the air. Whether these are due to chemicals released by the crop, to rising summer ozone levels, or to other factors remains unclear.
调查在油菜花期出现症状的人群的特应性以及症状、呼气峰值流速和支气管反应性的变化。
研究了37名在油菜花期相关症状问题上回答为阳性的人以及24名无此类症状的对照者，不过并非所有人都参与了研究的所有部分。所有这些人先前都在对农村人口随机样本的横断面调查中被识别出来。通过皮肤点刺试验、总免疫球蛋白E（IgE）和放射变应原吸附试验（RAST）检测来评估特应性。通过组胺激发试验测量支气管反应性（PC20）。在油菜花期之前和花期期间都测量了总IgE和支气管反应性。受试者记录每天早晚的症状和呼气峰值流速，从花期前开始，持续到花期并进入草花粉季节，以此监测每日变化。
在23名接受检测的人中，只有2例显示对油菜过敏的证据，在这23名接受检测的人中，包括这2例在内，只有10例为特应性。病例组在该季节眼部、鼻部和头痛症状有所增加，这验证了先前横断面调查中使用的问卷。在16例接受检测的病例中有12例以及15名对照者中有7例显示PC20出现季节性下降；病例组的下降幅度显著大于对照组。呼气峰值流速图表显示在该季节没有下降或变异性增加的证据。
抱怨与油菜开花有关症状的人很少对该植物过敏，且不到一半为特应性。然而，他们在该季节通常表现出支气管反应性增加，在某些情况下这可能是由于其他过敏原，但在其他情况下是由于空气的非特异性刺激作用。这些是由于作物释放的化学物质、夏季臭氧水平上升还是其他因素所致尚不清楚。
