Table 2.

Demographic and exacerbation data derived from the study cohort

Characteristics	No exacerbations	≥1 exacerbation		Total
	n	Column %	n	Column %	Row %	n	Column %
Total	481,822	100.0	252,292	100.0	34.4	734,114	100.0
Gender
Male	276,033	57.3	153,216	60.7	35.7	429,249	58.5
Female	205,789	42.7	99,076	39.3	32.5	304,865	41.5
Age at date of asthma diagnosis
≤ 1 year	25,495	5.3	20,437	8.1	44.5	45,932	6.3
> 1–2 years	24,329	5.0	20,226	8.0	45.4	44,555	6.1
> 2–3 years	25,722	5.3	19,414	7.7	43.0	45,136	6.1
4–12 years	262,219	54.4	133,291	52.8	33.7	395,510	53.9
13–17 years	144,057	29.9	58,924	23.4	29.0	202,981	27.6
Asthma index datea
2004	41,964	10.3	17,066	8.9	28.9	59,030	9.8
2005	45,312	11.1	18,947	9.9	29.5	64,259	10.7
2006	51,128	12.6	21,546	11.2	29.6	72,674	12.1
2007	45587	11.2	20,957	10.9	31.5	66,544	11.1
2008	38,942	9.6	18,952	9.9	32.7	57,894	9.7
2009	40,484	10.0	20,025	10.4	33.1	60,509	10.1
2010	38,010	9.4	19,044	9.9	33.4	57,054	9.5
2011	42,088	10.4	19,975	10.4	32.2	62,063	10.4
2012	62,761	15.4	35,703	18.6	36.3	98,464	16.5

^aValues are for patients 4–17 years at asthma index date