Non-severe Asthma Severe Asthma 25 20- 15 10 5 20 40 60 80 20 40 60 80 Age (years) Fig 2. The histogram of age distribution by asthma severity. This histogram shows the difference in age distribution among severe and nonsevere asthmatics. The distribution of nonsevere asthmatics was skewed to the left reflecting younger age, and severe asthmatics were shifted to older age. doi:10.1371 joumal.pone.0133490.g002 0.8- A B. 0.6- Age: >45 yrs 0.4 0.2 Age: between 18 and 45 yrs A t et 10 20 30 40 50 60 70 10 20 30 40 50 60 Age (yrs) Asthma Duration (yrs) Fig 3. Probability of severe asthma as a function of age, and asthma duration. [A] The probability of severe asthma increases as a function of age until the age of 45 years, at which time the probability of severe asthma plateaus. The fitted final logistic regression model, which included variables associated with severe asthma and adjusted for asthma duration, a history of Gastro-esophageal Reflux Disease, and nasal corticosteroids use, was applied to calculate the probability of severe asthma. [B] Individuals were stratified by age groups into older or young adult asthma in order to evaluate the effect of asthma duration on risk of severe asthma in those older or younger than 45 years. Asthma duration has a lesser effect than age on the probability of severe asthma in younger adult asthmatics. In older asthmatics (age 45 years and older), asthma duration has no significant effect on risk of severe asthma. Probability of Severe Asthma Percent of total

1st Edition

ISBN:9781938168130

Author:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark Womble

Publisher:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark Womble