Table 1 Survival rates and survival times of patients with amyotrophic lateral sclerosis across demographic and clinical variables in the SLAP, a population based study (1998–1999)

Variable	n	No of events* (%)	Median survival time from onset (months)	Median survival time from diagnosis (months)	4 year survival rate (%)	Log rank
Total sample	126	92 (73)	27.5 (6.6–97.8)	15.7 (0.3–46.9)	27
Gender						0.06 p = 0.8
F	48	37 (77)	34.4 (11.6–91.4)	20.1 (2.6–45.1)	23
M	78	55 (71)	26 (6.6–97.8)	13.2 (0.3–46.9)	29
Age groups (y)						19.4 p = 0.0002
⩽45	11	3 (27)	39.3 (29.6–54.5)	26.3 (24–42)	73
45–65	51	42 (81)	29.4 (6.6–66.9)	18.6 (0.3–46.9)	19
65–75	54	37 (70)	27.6 (6.8–97.8)	12.1 (1–45)	30
>75	10	10 (100)	21 (12.9–51.9)	10.6 (7–36.7)	0
Site of onset
Bulbar	24	22 (92)	22.2 (11.6–48.7)	12.5 (2.8–36.7)	8	14.4 p = 0.0007
Spinal	93	61 (66)	34.2 (6.6–97.8)	18 (0.3–46.9)	34
Generalised	9	9 (100)	32.2 (13.9–52)	20 (2.8–30.5)	0
Onset diagnosis interval (months)
⩽9	61	42 (69)	21.5 (6.6–53.1)	15.3 (0.8–45.1)	31	0.5 p = 0.5
>9	65	50 (77)	38 (14.8–97.8)	18.6 (0.3–46.9)	23
El Escorial category at diagnosis
Definite	28	24 (86)	26.3 (7.8–91.4)	15.4 (0.8–36)	14	14.4 p = 0.002
Probable	43	33 (77)	27.8 (6.6–66.9)	18.8 (0.3–46.9)	23
Possible	44	25 (57)	34.2 (6.8–97.8)	18.1 (1.8–41.2)	43
Suspect	11	10 (91)	29.9 (12.9–55)	15.3 (1–30.5)	9
Airlie House category at diagnosis
Probable laboratory supported	29	18 (62)	33.4 (6.8–97.8)	16.5 (1.8–41.2)	38	1.1
Possible	15	7 (47)	34.2 (12.2–50.7)	24.2 (6.2–36.7)	53
Bulbar signs at diagnosis
Yes	99	81 (82)	27.8 (6.6–97.8)	18 (0.3–45.1)	18	11.8 p = 0.0006
No	27	11 (41)	21.4 (6.8–66.9)	12.1 (1.8–46.9)	59
Predominance of UMN signs
Yes	14	8 (57)	45.2 (19.4–91.4)	23.8 (12.4–46.9)	43	2.8 p = 0.09
No	112	84 (75)	27.1(6.6–97.8)	14.1 (0.3–45.1)	25

*Including deaths (n = 88) and tracheostomies (n = 13).
UMN, upper motoneuron.