Table 1

Kaplan–Meier estimates of the median time from MS onset to landmark disability scores and age at landmark disability scores by potential risk factors

Factor	n	Median time to EDSS 4 from MS clinical onset (95% CI)	p Value*	n	Median age at EDSS 4 (95% CI)	p Value*	n	Median time to EDSS 6 from MS clinical onset (95% CI)	p Value*	n	Median age at EDSS 6 (95% CI)	p Value*
Overall	358	5 (4 to 6)	–	360	51 (49 to 53)	–	392	9 (8 to 10)	–	402	55 (54 to 56)	–
Sex
Female	180	4 (3 to 6)	0.28	181	51 (48 to 53)	0.05	199	8 (7 to 10)	0.25	206	55 (52 to 57)	0.09
Male	178	6 (5 to 7)	0.28	179	51 (50 to 53)	0.05	193	10 (9 to 12)	0.25	196	55 (54 to 58)	0.09
Age at onset
<30	39	10 (5 to 13)	0.005	39	33 (31 to 39)	<0.0001	43	13 (9 to 19)	<0.0001	43	39 (35 to 45)	<0.0001
30 to <40	75	8 (5 to 10)		75	43 (42 to 46)		82	13 (11 to 15)		82	48 (46 to 50)
40 to <50	143	5 (4 to 6)		143	50 (49 to 51)		159	9 (7 to 10)		159	54 (53 to 55)
50 and older	101	4 (3 to 4)		101	60 (59 to 62)		108	6 (5 to 9)		108	63 (62 to 65)
Onset symptoms
Motor
Absent	162	7 (5 to 8)	0.04	162	51 (49 to 55)	0.07	171	10 (9 to 12)	0.25	171	56 (54 to 60)	0.18
Present	189	4 (3 to 6)	0.04	189	51 (49 to 52)	0.07	212	9 (7 to 10)	0.25	212	55 (53 to 56)	0.18
Motor
Absent	162	7 (5 to 8)	0.007	162	51 (49 to 55)	0.19	171	10 (9 to 12)	0.06	171	56 (54 to 60)	0.14
Unilateral	127	5 (4 to 7)		127	51 (49 to 53)		143	9 (8 to 12)		143	55 (53 to 58)
Bilateral	62	4 (2 to 4)		62	51 (47 to 54)		69	6 (5 to 10)		69	54 (50 to 57)
Sensory
Absent	196	4 (4 to 6)	0.12	196	51 (48 to 53)	0.24	215	9 (7 to 10)	0.32	215	55 (53 to 57)	0.35
Present	155	6 (4 to 7)	0.12	155	51 (49 to 53)	0.24	168	10 (9 to 13)	0.32	168	56 (54 to 58)	0.35
Sensory
Absent	196	4 (4 to 6)	0.008	196	51 (48 to 53)	0.50	215	9 (7 to 10)	0.03	215	55 (53 to 57)	0.65
Unilateral	88	7 (5 to 10)		88	51 (49 to 55)		94	12 (9 to 15)		94	56 (54 to 59)
Bilateral	67	4 (3 to 7)		67	51 (49 to 55)		74	9 (6 to 11)		74	56 (53 to 61)
CB
Absent	286	6 (4 to 7)	0.20	286	51 (49 to 53)	0.95	314	10 (9 to 11)	0.18	314	55 (54 to 57)	0.72
Present	65	4 (4 to 6)	0.20	65	50 (47 to 55)	0.95	69	7 (6 to 12)	0.18	69	54 (51 to 59)	0.72
Visual
Absent	339	5 (4 to 6)	0.26	339	51 (50 to 53)	0.01	370	9 (8 to 11)	0.32	370	55 (54 to 57)	0.04
Present	12	7.5 (4-NA)	0.26	12	40.5 (35-NA)	0.01	13	13 (3-NA)	0.32	13	43 (38-NA)	0.04

*Log-rank test.
Bold figures represent statistically significant findings.
CB, cerebellar/brainstem; EDSS, Expanded Disability Status Scale; MS, multiple sclerosis; NA, not available.