Incidence rates
According to model A, the incidence rate of physician-diagnosed asthma for the period 1996 to 2006 was 2.4/1000/year (in total 108 new cases during the ten year follow up) with minor differences between sex and age groups. Incidence of asthma medication use was higher among women than men (4.7/1000/year vs 3.4/1000/year, p=0.028). The incidence rate of asthma for the period 2006 to 2016 was 2.6/1000/year (in total 93 new cases), and higher among women than men (3.5/1000/year vs 1.7/1000/year, p=0.001). The incidence of asthma medication use was also higher among women than men (5.7/1000/year vs 3.3/1000/year, p=0.001) (Table 3).
According to model B, the incidence of physician-diagnosed asthma for the period 1996 to 2006 was 4.4/1000/year (in total 225 new cases) and the incidence of asthma medication use was 7.4/1000/year. For the period 2006 to 2016 the corresponding incidence rates were 4.8/1000/year (in total 188 new cases) and 8.3/1000/year, respectively. These incidence estimates were all significantly higher among women (Table 3).
According to model C, where the population at risk only excluded those reporting the outcome variable at baseline, the incidence rates of asthma medication use and recurrent wheeze were in between the estimations from models A and B. The incidence of recurrent wheeze did not differ by sex in any model or observation period (Table 3).