Determinants of undiagnosed asthma.
BACKGROUND
The conformity between asthma diagnosed in a clinical setting and asthma from an epidemiological point of view has not been much studied.


METHODS
History, symptoms, and clinical findings in persons with and without a previous physician diagnosed asthma were studied among persons classified as having asthma according to an epidemiological definition.


RESULTS
Smoking was more prevalent in persons not diagnosed as having asthma prior to the study (n = 96), than in those with a previous asthma diagnosis (n = 119), (60% vs. 41%, P = 0.006). Positive skin prick test (SPT) was less common (39.6% vs. 58.0%, P = 0.009), lung function expressed as FEV1.0 in percentage of predicted was better (92.1 vs. 85.4, P = 0.018), reversibility to a bronchodilator was smaller (mean reversibility 4.0% vs. 6.2% of predicted, P = 0.003) and symptoms were less frequently reported (P < 0.001) by those who had not a physician diagnosed asthma prior to the study.


CONCLUSIONS
The asthma diagnosis is often overlooked by the medical profession in patients with mild disease. Furthermore, smoking seems to worsen asthma exacerbations in patients with mild disease.
The Are Clinic, Sweden.
L
L
Nathell
K
K
Larsson
I
I
Jensen
D000328:Adult; D001249:Asthma / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology*; D001993:Bronchodilator Agents / Q000627:therapeutic use; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D015994:Incidence; D007407:Interviews as Topic; D008297:Male; D008499:Medical Records; D010808:Physical Examination; D012140:Respiratory Tract Diseases / Q000150:complications / Q000453:epidemiology; D012882:Skin Tests; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires
D001993:Bronchodilator Agents