Remission of asthma in the middle aged and elderly: report from the Obstructive Lung Disease in Northern Sweden study
- aRespiratory Epidemiology Unit, Division of Allergy, Department of Occupational Health, National Institute for Working Life, Umeå and Stockholm, Sweden, bThe OLIN Study Group, Department of Medicine, Central Hospital of Norrbotten, Luleå-Boden, Sweden, cLuleå Health Care Centre, dDepartment of Lung Medicine and Allergy, University Hospital of Northern Sweden, Umeå, Sweden
- Dr B Lundbäck, Respiratory Epidemiology Unit, Department of Occupational Health, National Institute for Working Life, P O Box 7654, SE 907 13, Umeå, Sweden.
- Received 19 October 1998
- Revision requested 1 December 1998
- Revised 1 March 1999
- Accepted 24 March 1999
Abstract
BACKGROUND Remission of asthma in adults has been considered to be low but is still not well documented. In children remission occurs with a rate estimated at approximately 50%. Remission of asthma in middle aged and elderly subjects was investigated as part of a population based study of respiratory diseases in Northern Sweden.
METHODS In 1986 86% of 6610 subjects participated in a questionnaire survey. After a clinical validation study 300 subjects were diagnosed as having current asthma. In 1996 5935 subjects of the cohort could be traced for a third survey and 87% participated. Of the subjects with current asthma in 1986, 267 participated. In addition, 60 symptomatic subjects were classified as suspected asthma and 58 of them participated in 1996. Remission of asthma was defined as no recurrent wheeze, no attacks of shortness of breath, and no use of asthma medicines in 1996.
RESULTS Remission of asthma during the 10 year period under study was 6%. In subjects with suspected asthma, remission occurred in 22%. The average annual remission rate was less than 1%. Remission was associated with previously mild disease and cessation of smoking.
CONCLUSION Remission of asthma or the disappearance of its symptoms to an asymptomatic latent phase appeared to be rare in middle aged and elderly subjects.
