Table 1.
Comparison of baseline characteristics between clinical phenotypes in all individuals with ALS–FTD spectrum disorder
| ALS n = 103 |
ALS–FTD n = 47 |
bvFTD n = 57 |
Missing data* | PALSvsALS−FTD | PALSvsbvFTD | PALS−FTDvsbvFTD | |
|---|---|---|---|---|---|---|---|
| Age at MRI, years | 58.9 (10.3) | 62.6 (9.6) | 62.9 (7.5) | 0.0% | 0.04 | 0.005 | 0.85 |
| Sex, male% | 58 (56.3%) | 28 (59.6%) | 36 (63.2%) | 0.0% | 0.71 | 0.40 | 0.71 |
| Education, years | 16.7 (12.0) | 15.0 (2.8) | 16.1 (2.8) | 0.0% | 0.72 | 0.09 | 0.09 |
| Disease duration, monthsa | 23.9 (200.1) | 28.4 (126.0) | 37.3 (201.2) | 0.0% | 0.20 | 0.0004 | 0.06 |
| Diagnostic delay, months | 17.7 (17.6) | 36.8 (34.6) | 46.5 (33.2) | 0.0% | < 0.0001 | < 0.0001 | 0.007 |
| MMSE | 27.7 (2.8) | 24.1 (5.7) | 24.3 (4.9) | 6.3% | < 0.0001 | < 0.0001 | 0.87 |
| Genetic pathogenic variantsb | n = 99 | n = 45 | n = 57 | 2.9% | – | – | – |
| C9orf72 | 7 (7.1%) | 10 (22.2%) | 31 (54.4%) | 0.009 | < 0.0001 | 0.001 | |
| GRN | 0 (0.0%) | 0 (0.0%) | 11 (19.3%) | 1.00 | < 0.0001 | 0.002 | |
| MME | 1 (1.0%) | 0 (0.0%) | 0 (0.0%) | 1.00 | 1.00 | 1.00 | |
| TBK1 | 0 (0.0%) | 1 (2.2%) | 1 (1.6%) | 0.31 | 0.37 | 1.00 | |
| TARDBP | 0 (0.0%) | 0 (0.0%) | 2 (3.5%) | 1.00 | 0.13 | 0.50 | |
| FTLD/ALS-TDPc | n = 21 | n = 7 | n = 27 | 73.4% | 0.0003 | < 0.0001 | 0.13 |
| Type A | 1 (4.8%) | 1 (14.3%) | 14 (51.9%) | – | – | – | – |
| Type B/E | 3 (14.3%) | 6 (85.7%) | 9 (33.3%) | – | – | – | – |
| Type C | 0 (0.0%) | 0 (0.0%) | 3 (11.1%) | – | – | – | – |
| Non-specific | 17 (81.0%) | 0 (0.0%) | 1 (3.7%) | – | – | – | – |
| SuStaIn stage | 3.3 (5.2) | 12.1 (7.7) | 15.6 (7.2) | 0.0% | < 0.0001 | < 0.0001 | 0.02 |
Bold values indicate statistically significant results
Data are presented as mean (standard deviation) for the continuous variables, and as number (frequency) for the categorical variables
ALS amyotrophic lateral sclerosis, ALS–FTD amyotrophic lateral sclerosis-frontotemporal degeneration, bvFTD behavioral variant frontotemporal degeneration, MMSE Mini-Mental Status Examination, FTLD/ALS-TDP frontotemporal lobar degeneration or amyotrophic lateral sclerosis with TDP-43 inclusions
*The percentage of individuals with missing data
aData presented as median (range)
bNumber of individuals for genetic screening
cNumber of individuals receiving neuropathological examination