Natural history of asthma: a 23-year followup of college students

Abstract

Objective: A 23-year followup study of 1,601 college students who were initially evaluated for evidence of asthma and allergic rhinitis by direct interviews, physical examination, laboratory tests, and repeated questionnaires was conducted.

Methods and results: The individuals were located through addresses from the alumnae office. Of these, 1,021 (64%) returned their completed questionnaires and these included 738 (72%) who had allergy skin tests as freshmen. A similar proportion of our total population of 1,021 were skin tested as freshmen compared with the original study population of 1,836 in the freshmen year (72% versus 68%). This difference was not statistically significant. Among these 738 alumnae, with a mean age of 40 years, there were a total of 84 with a history of asthma. At the time of the 23-year followup, 44 (52%) were considered to have active asthma and 40 (48%) were symptom free. A majority (85%) of those with inactive asthma were symptom free for 5 years or longer. Of those with active asthma, 50% felt they were improved, 39% unchanged, 9% felt worse, and 2% were unknown. Atopy was a non-prognostic indicator of asthma outcome as determined by scratch skin testing as college freshmen. New asthma occurred in 36 (5.2%) of those at risk to develop new asthma in this 23-year period for a rate of 0.23% per year.

Conclusion: This 23-year followup study demonstrates that the cumulative prevalence of asthma continues to increase as the individuals become older. The asthma symptoms were no longer present or were improved in about three-fourths of the asthma subjects in this 40-year-old age group. Of the remainder, most symptoms were unchanged and a small number felt worse.