Table 1

Incidence of diabetes mellitus between ankylosing spondylitis group and non-ankylosing spondylitis group

Variable	Ankylosing spondylitis				Non-ankylosing spondylitis
Variable	N	Event	Person- years	Incidence	N	Event	Person- years	Incidence	Incidence rate ratio (95% CI)*	P value
All	2757	164	11 447	1.43	11 028	972	81 955	1.19	1.21 (1.02 to 1.43)	0.025
Sex
Male	1633	99	6890	1.44	6532	552	48 496	1.14	1.26 (1.02 to 1.56)	0.033
Female	1124	65	4557	1.43	4496	420	33 459	1.26	1.14 (0.88 to 1.48)	0.338

Incidence: per 100 person-years.
*Incidence rate ratio: ankylosing spondylitis versus non-ankylosing spondylitis (95% CI).