Table 2

IRs and IRRs of the studied non-vertebral fracture outcomes in AS and matched controls

	Men		Women
	AS	Matched controls	AS	Matched controls
Non-vertebral fracture
Events, n	603	2572	371	1534
IRs with 95% CI	11.9 (11.0 to 12.9)	10.0 (9.7 to 10.4)	14.5 (13.1 to 16.1)	11.8 (11.1 to 12.4)
IRRs with 95% CI, crude	1.2 (1.1 to 1.3)	Ref	1.2 (1.1 to 1.4)	Ref
IRRs with 95% CI, adjusted*	1.2 (1.1 to 1.3)	Ref	1.2 (1.1 to 1.4)	Ref
Fracture of the humerus, forearm or hip
Events, n	210	703	166	741
IRs with 95% CI	4.0 (3.5 to 4.6)	2.7 (2.5 to 2.9)	6.3 (5.4 to 7.3)	5.5 (5.1 to 6.0)
IRRs with 95% CI, crude	1.5 (1.3 to 1.8)	Ref	1.1 (0.95 to 1.3)	Ref
IRRs with 95% CI, adjusted*	1.5 (1.3 to 1.7)	Ref	1.1 (0.9 to 1.3)	Ref
Proximal humerus fracture
Events, n	50	182	44	191
IRs with 95% CI	0.9 (0.7 to 1.2)	0.7 (0.6 to 0.8)	1.6 (1.2 to 2.2)	1.4 (1.2 to 1.6)
IRRs with 95% CI, crude	1.4 (1.0 to 1.9)	Ref	1.2 (0.8 to 1.6)	Ref
IRRs with 95% CI, adjusted*	1.4 (0.99 to 1.9)	Ref	1.1 (0.8 to 1.6)	Ref
Distal forearm fracture
Events, n	87	320	103	457
IRs with 95% CI	1.7 (1.3 to 2.0)	1.2 (1.1 to 1.3)	3.8 (3.2 to 4.7)	3.4 (3.1 to 3.7)
IRRs with 95% CI, crude	1.4 (1.1 to 1.7)	Ref	1.1 (0.9 to 1.4)	Ref
IRRs with 95% CI, adjusted*	1.4 (1.1 to 1.7)	Ref	1.1 (0.9 to 1.4)	Ref
Hip fracture
Events, n	85	230	28	143
IRs with 95% CI	1.6 (1.3 to 2.0)	0.9 (0.8 to 1.0)	1.0 (0.7 to 1.5)	1.1 (0.9 to 1.3)
IRRs with 95% CI, crude	1.9 (1.5 to 2.4)	Ref	1.0 (0.7 to 1.5)	Ref
IRRs with 95% CI, adjusted*	1.8 (1.4 to 2.3)	Ref	1.0 (0.6 to 1.4)	Ref

IRs are presented as number of fractures per 1000 person-years at risk with 95% CI. Statistically significant values are written in bold.
*Adjusted for history of prior fracture at study entry.
AS, ankylosing spondylitis; IRRs, IR ratios; IRs, incidence rates; Ref, reference.