Description of the MSA sample at inclusion and over time (N=536)
| Characteristic | N (%) | Mean±SD |
| At inclusion | ||
| Sex | ||
| Male | 268 (50.0) | |
| Female | 268 (50.0) | |
| Centre | ||
| Bordeaux | 308 (57.5) | |
| Toulouse | 228 (42.5) | |
| Age at first symptom onset | 60.6±8.1 | |
| Age at cohort entry | 65.1±8.0 | |
| Years since first symptom onset | 4.5±2.4 | |
| Diagnosis | ||
| MSA-C, with predominant cerebellar impairment | 173 (32.3) | |
| MSA-P, with predominant parkinsonism | 363 (67.7) | |
| Diagnosis certainty | ||
| Possible | 136 (25.4) | |
| Probable | 400 (74.6) | |
| Orthostatic hypotension | ||
| Presence | 361 (67.4) | |
| Absence | 175 (32.6) | |
| Urinary disorder | ||
| Presence | 365 (68.1) | |
| Absence | 171 (31.9) | |
| Treatments | ||
| L-dopa | 366 (68.3) | |
| Antihypotensive treatment | 161 (30.0) | |
| Antidepressants | 111 (20.7) | |
| Original MSA-QoL scale | ||
| Sum score for motor dimension/56 (n=330) | 27.0±12.2 | |
| Sum score for non-motor dimension/48 (n=344) | 20.1±8.9 | |
| Sum score for emotional/social dimension/56 (n=326) | 25.6±13.0 | |
| Modified MSA-QoL scale | ||
| Sum score for motor dimension/44 (n=333) | 25.1±9.8 | |
| Sum score for oropharyngeal dimension/16 (n=387) | 4.3±3.8 | |
| Sum score for non-motor dimension/40 (n=350) | 16.6±7.8 | |
| Sum score for emotional/social dimension/56 (n=326) | 25.6±13.0 | |
| Disability degree (n=520) | ||
| Completely independent (stage I) | 111 (20.7) | |
| Not completely independent (stage II) | 239 (44.6) | |
| More dependent (stage III) | 105 (19.6) | |
| Very dependent (stage IV) | 63 (11.8) | |
| Totally dependent (stage V) | 2 (3.0) | |
| During follow-up | ||
| Visits | 1501 | |
| Visits per patient | 2.8±1.9 | |
| Years of follow-up | 2.3±2.1 | |
| Early dropout | 87 (16.2) | |
| Death | 338 (63.1) | |
MSA, multiple system atrophy; QoL, quality of life.