Table 1

Baseline demographics of C9orf72-tested ALS cases by country

VariableBelgium
n=482
Ireland
n=645
Italy
n=897
The Netherlands
n=2153
UK
n=929
p Value(χ2)Combined
N=5106
Included after missing values removed477 (99.0%)640 (99.2%)867 (96.7%)2037 (94.6%)904 (97.3%)4925 (96.5%)
Sex
 Female180 (37.3)266 (41.6%)411 (47.4%)844 (41.4%)352 (38.9%)2053 (41.7%)
 Male297 (62.3)374 (58.4%)456 (52.6%)1193 (58.6%)552 (61.1%)<0.0012872 (58.3%)
Age of onset
 Median61.463.066.863.061.363.1
Diagnostic delay
 Short161 (33.8%)193 (30.2%)285 (32.9%)702 (43.5%)300 (33.2%)1641 (33.3%)
 Medium163 (34.2%)211 (33.0%)293 (33.8%)683 (33.5%)298 (33.0%)1648 (33.5%)
 Long153 (32.1%)236 (36.9%)289 (33.3%)652 (32%)306 (33.8%)0.5591636 (33.2%)
Site of onset
 Spinal326 (68.3%)437 (68.3%)583 (67.2%)1333 (65.4%)610 (67.5%)3289 (66.8%)
 Bulbar151 (31.7%)203 (31.7%)284 (32.8%)704 (34.6%)294 (32.5%)0.5401636 (33.2%)
C9orf72
 Normal392 (82.2%)578 (90.3%)805 (92.8%)1861 (91.4%)841 (93.0%)4477 (90.9%)
 Expanded85 (17.8%)62 (9.7%)62 (7.2%)176 (8.6%)63 (7%)<0.001448 (9.1%)
  • Diagnostic delay is defined by three tertiles per country labelled ‘short’, ‘medium’ and ‘long’ diagnostic delay to allow for variation in diagnostic delay between countries.

  • ALS, amyotrophic lateral sclerosis.