Table 1

Kaplan-Meier estimates and multivariable HRs of time to and age at secondary progression by potential risk factors

Factor	n	Median time to SPMS (95% CI)	p Value	Time to SPMS HR^† (95% CI)	p Value	n	Median age at SPMS (95% CI)	p Value	Age at SPMS HR^† (95% CI)	p Value
Overall	5162	21.4, 20.6 to 22.2	–			5169	53.7, 53.1 to 54.3

Gender
Women	3792	22.7, 21.8 to 23.7	<0.0005	1.0 (reference)	<0.0005	3796	54.4, 53.7 to 55.2	<0.0005	1.0 (reference)	<0.0005
Men	1370	17.1, 15.4 to 18.7	<0.0005	1.43, 1.30 to 1.58	<0.0005	1373	51.2, 49.9 to 52.5	<0.0005	1.43, 1.30 to 1.58	<0.0005

Age at onset (years)^*						^*
<30	2533	24.9, 23.8 to 26.0	<0.0005	1.05, 1.04 to 1.06^‡	<0.0005	2533	48.6, 47.6 to 49.6	<0.0005	–	–
30 to <40	1680	18.5, 17.3 to 19.7				1680	52.8, 51.7 to 53.8
40 to <50	761	12.2, 11.0 to 13.4				761	56.5, 54.9 to 58.0
50 and above	188	8.1, 7.0 to 9.3				188	64.8, 63.0 to 66.5

Onset symptoms
Motor
Absent	4131	22.0, 21.1 to 22.9	< 0.0005	1.0 (reference)	0.02	4137	54.1, 53.3 to 54.9	0.31	1.0 (reference)	0.004
Present	1031	18.6, 17.1 to 20.0	< 0.0005	1.03 to 1.31	0.02	1032	52.9, 51.7 to 54.1	0.31	1.12, 1.06 to 1.35	0.004

Sensory
Absent	2597	22.7, 21.8 to 23.5	0.22	1.0 (reference)	0.95	2603	53.4, 52.6 to 54.1	0.29	1.0 (reference)	0.68
Present	2565	23.1, 21.9 to 24.2	0.22	1.0, 0.89 to 1.13	0.95	2566	54.7, 53.3 to 55.2	0.29	1.03, 0.91 to 1.16	0.68

CAB
Absent	4511	23.1, 22.3 to 23.9	0.60	1.0 (reference)	0.3	4518	53.9, 53.2 to 54.5	0.18	1.0 (reference)	0.15
Present	651	22.0, 20.5 to 23.6	0.60	1.08, 0.93 to 1.26	0.3	651	52.8, 50.6 to 54.9	0.18	1.12, 0.96 to 1.30	0.15

ON
Absent	4251	21.4, 20.5 to 22.3	0.71	1.0 (reference)	0.34	4258	53.9, 53.2 to 54.6	0.02	1.0 (reference)	0.15
Present	911	21.4, 19.9 to 23.0	0.71	1.08, 0.93 to 1.25	0.34	911	52.6, 51.1 to 54.2	0.02	1.03, 0.96 to 1.30	0.15

↵* Seven patients for whom date at disease onset was unknown were excluded from all analyses of time to SPMS and from the analysis of the association between age at onset and age at SPMS.
↵† Derived from Cox regression analyses.
↵‡ HRs represent a per year increase in risk.
CAB, cerebellar, ataxia or brainstem; ON, optic neuritis; SPMS, secondary progressive multiple sclerosis.