Features that distinguish those who die from asthma from community controls with asthma

To evaluate risk factors for asthma mortality, an unmatched case-control st udy was undertaken in the Canadian prairie provinces of Alberta, Saskatchew an, and Manitoba. Those between the ages of 5 and 50 (inclusive) who died f rom an acute exacerbation of asthma were compared to a control group of peo ple with asthma from the same geographical areas who were contacted using r andom-digit dialing. Because no deaths occurred among residents less than 1 5 years old, this analysis was limited to cases and controls between 15 and 50 years old. Of the 38 deaths that occurred between November 1992 and Oct ober 1995, data were obtained from next of kin for 35 (92.1%). Of the 210 p otential controls that were identified, 142 returned completed questionnair es (67.6%). Cases were more likely than controls to have asthma reported to be severe, to have experienced nocturnal symptoms, to have had cardiopulmi nary resuscitation (CPR)/intubation, and to have had more healthcare utiliz ation in the previous year. Medication use was also more common among cases compared to controls. Specific asthma triggers were reported more often fo r cases than controls; weather changes, excitement, depression, and stress showed the greatest case control differences. Although a number of very str ong risk factors for death from asthma were identified, death from asthma i s so rare in this age group that it is not possible to label an individual as "likely" to die from asthma. Nonetheless, patients, caregivers, and heal th professionals should be aware of indicators that would suggest greater r isk.