Table 3

Kaplan Meier survival analysis and Cox regression multiple analysis: estimated times to onset of SP and to DSS 8 from onset of progression, and estimated risk (HR) of attaining SP and DSS8 from onset of progression in patients grouped by clinical and demographic baseline features

Survival analysis from disease onsetSurvival analyses from onset of progression (SP patients only)
Kaplan–Meier analysisCox regression multiple analysisKaplan–Meier analysisCox regression multiple analysis
n (% censored)Mean years to onset of SP (95% CI)p ValueRisk of converting to SP MS; HR (95% CI)p Valuen (% censored)Mean years to DSS 8 (95% CI)p ValueRisk of reaching DSS 8; HR (95% CI)p Value
Total population769 (33.8)21.4 (19.5 to 23.1)474 (33.1)15.2 (13.7 to 16.5)
Gender
 Male240 (24.6)15.9 (13.4 to 17.1)<0.0011.41 (1.17 to 1.71)0.001165 (33.9)15.5 (12.8 to 16.0)0.921.03 (0.81 to 1.31)0.80
 Female*529 (38.0)22.4 (21.4 to 26.1)309 (32.7)14.7 (13.3 to 16.7)
Age at onset
 ≤20145 (41.1)25.8 (21.7 to 29.9)<0.0010.52 (0.40 to 0.68)<0.00180 (35.0)13.9 (10.2 to 17.7)0.111.55 (1.10 to 2.18)0.01
 21–30371 (38.1)20.2 (18.2 to 21.7)<0.0010.65 (0.53 to 0.80)<0.001207 (30.0)15.3 (13.3 to 17.4)0.441.15 (0.89 to 1.48)0.29
 >30*285 (24.6)15.3 (13.3 to 17.3)187 (35.8)15.0 (13.4 to 16.6)
Relapses during year 1–2
 1380 (28.7)19.9 (18.3 to 21.5)0.010.63 (0.49 to 0.80)<0.001246 (34.1)16.4 (14.5 to 18.2)<0.0010.47 (0.35 to 0.63)<0.001
 2179 (30.2)16.7 (14.6 to 18.9)0.380.75 (0.57 to 0.99)0.041121 (38.8)14.2 (12.5 to 15.9)<0.0010.53 (0.38 to 0.74)<0.001
 ≥3*149 (34.2)15.1 (12.8 to 17.4)93 (24.7)9.6 (8.2 to 11.1)
No of symptoms at disease onset
 1515 (32.6)20.3 (19.2 to 23.6)0.751.19 (0.92 to 1.54)0.17321 (35.2)15.1 (13.7 to 16.3)0.171.00 (0.72 to 1.40)0.98
 >1*245 (36.7)19.9 (16.6 to 21.1)146 (28.1)13.9 (11.9 to 16.7)
Type of symptoms at disease onset
 Motor
  Present139 (28.8)18.0 (14.1 to 18.7)0.181.22 (0.93 to 1.61)0.1589 (28.1)15.6 (12.5 to 18.7)0.871.12 (0.78 to 1.61)0.55
  Absent*630 (34.9)20.0 (19.7 to 23.8)385 (34.3)15.1 (13.5 to 16.7)
 Sensory
  Present419 (35.6)20.7 (17.7 to 21.2)0.410.99 (0.75 to 1.30)0.93255 (32.9)15.3 (13.8 to 17.6)0.361.01 (0.71 to 1.41)0.97
  Absent*350 (31.7)19.7 (18.2 to 23.4)219 (33.3)13.9 (12.3 to 15.4)
 Cerebellar
  Present46 (30.4)18.7 (12.9 to 20.9)0.621.16 (0.79 to 1.71)0.4430 (16.7)9.5 (6.1 to 11.3)0.0012.21 (1.40 to 3.37)<0.001
  Absent*723 (34.0)19.7 (19.5 to 23.3)444 (34.2)14.8 (14.0 to 17.0)
 Brainstem
  Present154 (36.4)19.2 (16.3 to 24.3)0.751.12 (0.83 to 1.52)0.4491 (23.1)11.0 (8.8 to 13.0)<0.0011.91 (1.32 to 2.79)<0.001
  Absent*615 (33.2)20.1 (17.4 to 19.8)383 (35.5)15.7 (!4.5 to 17.8)
  Optic
  Present170 (32.4)20.3 (16.2 to 20.7)0.861.04 (0.78 to 1.39)0.77110 (38.2)14.9 (12.9 to 16.7)0.220.90 (0.62 to 1.30)0.58
  Absent*599 (34.2)19.5 (19.0 to 23.0)364 (31.6)14.4 (13.3 to 16.4)
  • Multiple Cox regression analysis: risk (HR) of conversion to SP MS and of attaining DSS 8 from onset of secondary progression according to the concomitant effect of clinical and demographic baseline features.

  • *Reference category.

  • DSS, Disability Status Scale; MS, multiple sclerosis; SP, secondary progressive.