Prevalence and associated factors of frailty and sarcopenia in multiple system atrophy and progressive supranuclear palsy: a cross-sectional study

To investigate the prevalence of, and clinicodemographic factors associated with, frailty and sarcopenia in patients with multiple system atrophy or progressive supranuclear palsy.A total of 264 participants were recruited in this study. Demographic and clinical data were collected through structured interviews. Frailty was assessed with the clinical frailty scale (CFS), and sarcopenia was assessed with the simple five-item scoring questionnaire (SARC-F).The prevalence of frailty and sarcopenia was 48.57% and 35.71% in multiple system atrophy, and 51.09% and 39.13% in progressive supranuclear palsy. Multiple system atrophy patients with frailty or sarcopenia were more likely to be female and have longer disease duration, greater motor impairment, greater non-motor burden, and lower life quality. In multiple system atrophy, frailty was associated with reduced motor function and sarcopenia was associated with female sex, reduced motor function, and orthostatic hypotension. Progressive supranuclear palsy patients with frailty or sarcopenia had more severe motor impairment and non-motor burden, longer disease duration, and lower life quality. In progressive supranuclear palsy, frailty was associated with mentation and gait/midline symptoms, while sarcopenia was associated with reduced daily activity and severe gait/midline symptoms.Frailty and sarcopenia may be more common among patients with multiple system atrophy or progressive supranuclear palsy than among the general population, and they are associated with more severe forms of the two diseases. Prospective studies are necessary to clarify causal relationships between frailty/sarcopenia and clinical manifestations of multiple system atrophy and progressive supranuclear palsy.