Rönmark E, Lundbäck B, Jönsson E, Jonsson A C, Lindström M, Sandström T
National Institute for Working Life, Department of Occupational Health, Umeå, Sweden.
Allergy. 1997 Nov;52(11):1071-8. doi: 10.1111/j.1398-9995.1997.tb00178.x.
Incidence studies offer a better opportunity to study risk factors for asthma than do prevalence studies. However, regular prospective follow-ups of large cohorts are difficult to perform, and that is why direct measurement of the incidence rate of asthma is almost impossible. Thus, cross-sectional follow-up studies of defined cohorts can be used to provide data on incidence. In 1986, a postal questionnaire survey on respiratory symptoms and diseases was performed in the northernmost province of Sweden. The population sample comprised all subjects born in 1919-20, 1934-5, and 1949-50 in eight representative areas of the province, which comprises 25% of the total area of Sweden. Completed answers were given by 5698 subjects (86%) of the 6610 subjects invited to the study. In 1992, the cohort was invited to a follow-up survey during the same season as in 1986, and 6215 subjects were traced. Of the 5393 subjects who answered the questionnaire, 4932 had participated in the 1986 survey, or 87% of those who participated in 1986. For the period 1986-92, the cumulative incidences of asthma were 4.9 and 5.0%, respectively, as assessed by the questions, "Have you ever had asthma?" and "Have you been diagnosed as having asthma by a physician?" Thus, the results indicate a mean annual cumulative incidence of asthma of 0.8%. After correction of the results for subjects who were diagnosed as having asthma in the clinical part later in the 1986 study, the mean annual cumulative incidence of asthma was found to be 0.5%. Risk factors were family history of asthma (OR 3.46) and current and former smoking, while female sex was a strong trend.
发病率研究比患病率研究提供了更好的机会来研究哮喘的危险因素。然而，对大型队列进行定期的前瞻性随访很难实施，这就是直接测量哮喘发病率几乎不可能的原因。因此，对特定队列进行横断面随访研究可用于提供发病率数据。1986年，在瑞典最北部的省份进行了一项关于呼吸道症状和疾病的邮政问卷调查。人口样本包括该省八个代表性地区中1919 - 20年、1934 - 35年和1949 - 50年出生的所有受试者，该省占瑞典总面积的25%。受邀参加研究的6610名受试者中有5698名（86%）给出了完整答案。1992年，该队列被邀请在与1986年相同的季节进行随访调查，追踪到了6215名受试者。在回答问卷的5393名受试者中，有4932名参加了1986年的调查，占1986年参加者的87%。对于1986 - 1992年期间，通过“你曾经患过哮喘吗？”和“你是否被医生诊断为患有哮喘？”这两个问题评估，哮喘的累积发病率分别为4.9%和5.0%。因此，结果表明哮喘的年平均累积发病率为0.8%。在对1986年研究后期临床部分被诊断为患有哮喘的受试者的结果进行校正后，发现哮喘的年平均累积发病率为0.5%。危险因素是哮喘家族史（比值比3.46）以及当前和既往吸烟，而女性性别有强烈的趋势。
