TABLE 4.

Subgroup analysis of the association between optic neuritis and autoimmune diseases.

	Optic neuritis		Non-optic neuritis
	N	No. of autoimmune diseases	N	No. of autoimmune diseases	HR† (95% C.I.)	p value
Age
<65	1417	50	5657	149	1.42 (1.03–1.96)	0.033
≥65	430	12	1731	39	1.31 (0.68–2.51)	0.413
						p for interaction = 0.837
Gender
Female	952	41	3885	113	1.59 (1.11–2.27)	0.011
Male	895	21	3503	75	1.16 (0.72–1.89)	0.539
						p for interaction = 0.339
Corticosteroids
No	1246	43	4965	121	1.46 (1.03–2.07)	0.034
Yes	601	19	2423	67	1.27 (0.76–2.13)	0.354
						p for interaction = 0.614

^†Adjusted for all variables.