École Nationale Supérieure de
Techniques Avancées

Résumé

This report presents a study about the estimation of sejourn time in the differents impairment stages of the Multiple System Atrophy disease (MSA), based on the study of more than 700 patients from the french cohort.The method resorts to the use of complex statistic models including joint models et IRT models for longitudinal data in order to evaluate the death risk and the mean trajectories linked to the subscale of UMSARS IV and considering some caracteristics of the patients such as gender, age at baseline, MSA subtype, diagnosis certainty, and the duration between symptom onset and the first visit. After the study of our sample, gender and MSA subtype have no significatif effect on the underlying level of UMSARS IV and on the death risk unlike the diagnisis certainty. Despite differents behaviour on the impairment stages, men with probable diagnosis who suffered from a MSA-P and women with possible diagnosis who suffered from a MSA-C are respectively patients who have the shortest and the longest life epectancy in the disease impairment stages. Those results play a key role in the comprehension of the evolution of MSA even though some ajustment are needed to improve time estimations and to be adapted to UMSARS I, II and MSA-QoL scales.