Table 1.

Age-specific incidence rates (per 100,000 person-years), and CIR of patients under prolonged mechanical ventilation

Age group (years)	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007
Number of new cases	9,296	12,651	12,913	15,660	17,731	19,737	21,818	21,692	20,414	19,723
17 to 34	5.1	6.1	5.5	5.8	6.1	8.4	9.9	9.2	9.4	9.9
35 to 44	10.1	10.8	11.8	14.5	14.4	15.4	19.2	17.4	19.8	18.1
45 to 54	21.8	33.3	29.3	32.4	37.2	42.0	40.5	43.5	39.5	39.7
55 to 64	78.2	101.1	92.2	102.5	111.6	118.9	129.6	119.8	101.7	93.0
65 to 74	224.0	296.5	284.5	329.2	361.9	379.8	393.9	369.2	331.8	306.4
75 to 84	622.0	817.2	814.6	967.2	1,045.5	1,072.3	1,166.4	1,036.0	1,004.6	909.2
≥85	1,182.0	1,536.0	1,702.6	2,064.1	2,253.0	2,563.9	2,584.0	2,554.0	2,161.0	2,046.0
CIR	0.103	0.133	0.132	0.153	0.165	0.173	0.183	0.170	0.159	0.145

CIR, cumulative incidence rate (aged 17 to 85 years).