Parkinsonian single fallers versus recurrent fallers: different fall characteristics and clinical features.

The study aimed to compare the fall characteristics between parkinsonian single (P-SF) and recurrent fallers (P-RF), and the clinical features among parkinsonian non-fallers (P-NF), P-SF, P-RF and age-matched healthy controls. As many as 72 patients with PD and 74 healthy subjects completed the study. Each subject was evaluated for gait speed, timed up-and-go test, one-leg-stance test, six-minute walk test, five-times-sit-to-stand test, and Activities-specific Balance Confidence (ABC) scale at baseline. Subjects were then followed up for 12 months by telephone interview to record the fall incidence and fall characteristics. Among the PD patients, 12 fell once (P-SF) and 13 fell 2-29 times (P-RF), accounting for a total of 133 falls in the 12-month follow-up period. The most common fall-related activity for both P-SF and P-RF was walking. P-SF fell mostly outdoors due to "tripping", while P-RF mostly fell at home due to "muscle giving way". Clinical measures indicated that P-SF did not differ from P-NF. However, P-RF had significantly longer five-times-sit-to-stand time, shorter 6-min walk distance, and lower ABC score than P-SF. P-RF could be distinguished from P-SF by fall characteristics (i.e. location and perceived causes of falls), and by clinical measures including leg muscle weakness, reduced exercise endurance and increased level of fear of falling. Findings from the present study suggest that P-NF/P-SF and P-RF may require different intervention strategies to prevent future falls.