Tracing asthma by drug utilization in young adults

Information based on prescription data for respiratory diseases has shown to be valuable indicators of occurrence and severity of asthma in population-based studies. In a Danish study of persons aged 20-44 years at baseline in 2003 with follow-up in 2010 we collected information from the National Database of Prescriptions redeemed between 2000 and 2013. 5,046 persons participated both in 2003 and in 2010. From questionnaires at baseline actual asthma was defined as reporting ever having asthma and either having an asthma attack within the last 12 months or using asthma medication. Asthma at follow up was defined from either asthma attack or medication within the last 12 month. For each person and year the number of prescriptions of medicine for obstructive lung diseases (ATC code R03) and the number of all other prescriptions were calculated from 4,595 healthy, 200 with new asthma, 94 with remission of asthma, and 193 with persistent asthma. The figure shows the average annual number of prescriptions for the four groups stratified by sex. Persistent asthmatics had considerably higher number of redeemed R03 prescriptions compared to the other groups, while new-onset asthma showed an increased time trend. Remission had a low use of specific drugs but in males an increase with time in the use of other drugs was observed. Register based information on drug use seems to be a valuable tool for tracing asthma and concurrent comorbidity in larger populations.