Why do patients with Parkinson's disease fall? A cross-sectional analysis of possible causes of falls.

Background: Falls in Parkinson’s disease (PD) are associated with significant injury, disability, hospitalization, and reduced quality of life. Aims: To identify modifiable medical causes of falls in a cohort of PD patients. Methods: Eighty seven PD patients were interviewed and examined using validated scales assessing motor and nonmotor aspects of PD, comorbidities and medication use. The frequency of falls in the last month was the primary outcome measure. Falls were hypothesized to be associated with increasing age, advanced motor severity, particularly axial features (e.g., freezing and postural instability), and dyskinesia. Nonmotor features hypothesized to be associated with falls included; cognitive impairment, psychosis, sleep disorders, cardiovascular dysfunction, and ophthalmological and medical comorbidities. Results: Fallers had longer disease duration, higher Levodopa-equivalent doses, greater ‘On’ time with dyskinesia (all P<0.005), and higher scores on some Movement Disorder Society-Unified Parkinson’s Disease Rating Scale items, particularly axial scores. However, patients with falls did not differ from non-fallers in age or overall motor UPDRS scores. Severity of psychosis, executive cognitive impairment, autonomic (particularly cardiovascular) dysfunction and sleep disturbances (particularly REM sleep behavioral disorder) were significantly associated with falls (all P<0.005). Fallers more frequently reported use of antidepressants (both tricyclics and SSRIs) and neuroleptics (P