Intergenerational 20 year trends in the prevalence of asthma and hay fever in adults: the Midspan family study surveys of parents and offspring

Upton, M.N., McConnachie, A. , McSharry, C., Hart, C.L. , Davey Smith, G., Gillis, C.R. and Watt, G.C.M. (2000) Intergenerational 20 year trends in the prevalence of asthma and hay fever in adults: the Midspan family study surveys of parents and offspring. British Medical Journal, 321(7253), pp. 88-92. (doi: 10.1136/bmj.321.7253.88)

Abstract

<b>Objective</b>: To estimate trends between 1972-6 and 1996 in the prevalences of asthma and hay fever in adults. Design: Two epidemiological surveys 20 years apart. Identical questions were asked about asthma, hay fever, and respiratory symptoms at each survey. Setting: Renfrew and Paisley, two towns in the west of Scotland. <b>Subjects</b>: 1477 married couples aged 45-64 participated in a general population survey in 1972-6; and 2338 offspring aged 30-59 participated in a 1996 survey. Prevalences were compared in 1708 parents and 1124 offspring aged 45-54. <b>Main outcome measures</b>: Prevalences of asthma, hay fever, and respiratory symptoms. Results: In never smokers, age and sex standardised prevalences of asthma and hay fever were 3.0% and 5.8% respectively in 1972-6, and 8.2% and 19.9% in 1996. In ever smokers, the corresponding values were 1.6% and 5.4% in 1972-6 and 5.3% and 15.5% in 1996. In both generations, the prevalence of asthma was higher in those who reported hay fever (atopic asthma). In never smokers, reports of wheeze not labelled as asthma were about 10 times more common in 1972-6 than in 1996. With a broader definition of asthma (asthma and/or wheeze), to minimise diagnostic bias, the overall prevalence of asthma changed little. However, diagnostic bias mainly affected non-atopic asthma. Atopic asthma increased more than twofold (prevalence ratio 2.52 (95% confidence interval 1.01 to 6.28)) whereas the prevalence of non-atopic asthma did not change (1.00 (0.53 to 1.90)). <b>Conclusion</b>: The prevalence of asthma in adults has increased more than twofold in 20 years, largely in association with trends in atopy, as measured indirectly by the prevalence of hay fever. No evidence was found for an increase in diagnostic awareness being responsible for the trend in atopic asthma, but increased awareness may account for trends in non-atopic asthma.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: McConnachie, Professor Alex and Hart, Dr Carole and Gillis, Prof Charles and Davey Smith, Professor George and Upton, Dr Mark and Watt, Professor Graham
• Authors: Upton, M.N., McConnachie, A., McSharry, C., Hart, C.L., Davey Smith, G., Gillis, C.R., and Watt, G.C.M.
• Subjects: R Medicine > RA Public aspects of medicine
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Robertson Centre; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Public Health; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > General Practice and Primary Care; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Research Group: Midspan
• Journal Name: British Medical Journal
• Journal Abbr.: BMJ
• Publisher: BMJ Publishing Group
• ISSN: 0959-535X
• ISSN (Online): 1756-1833
• Copyright Holders: Copyright © 2000 BMJ Publishing Group
• First Published: First published in British Medical Journal 323(753):88-92
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher