Balance confidence and functional mobility are independently associated with falls in people with Parkinson's disease

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.

Knee extensor strength, dynamic stability, and functional ambulation: are they related in Parkinson's disease?

OBJECTIVE

To evaluate the relationship between knee extensor strength, postural stability, functional ambulation, and disease severity in Parkinson's disease (PD).

DESIGN

A cohort study.

SETTING

University research laboratory.

PARTICIPANTS

Patients (N=44) with idiopathic PD.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Participants were evaluated on their isokinetic knee extensor strength. Additionally, participants completed an assessment of their postural stability (Functional Reach Test for static stability and a dynamic postural stability assessment as measured by the center of pressure-center of mass moment arm during gait initiation). Participants also underwent an evaluation of their functional ambulation as measured by a 6-minute walk test. Lastly, participants were evaluated by a neurologist specially trained in movement disorders to assess neurologic status and disease severity using the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr disability score.

RESULTS

Knee extensor strength positively correlated with dynamic postural stability and negatively correlated with disease severity. Further, dynamic postural stability was negatively correlated to disease severity and positively correlated with functional ambulation in this cohort of patients with PD (P<.05). The results also suggest that the Functional Reach Test may be a valuable assessment tool to examine postural stability in PD.

CONCLUSIONS

These findings suggest a malleable relationship between knee extensor strength, dynamic stability, and disease severity in PD. Although strength is only one piece of the puzzle in the functional outcome of PD, these findings may assist clinicians in designing appropriate interventions aimed at increasing function and decreasing fall risk in PD.

Effects of moderate-volume, high-load lower-body resistance training on strength and function in persons with Parkinson's disease: a pilot study

Background. Resistance training research has demonstrated positive effects for persons with Parkinson's disease (PD), but the number of acute training variables that can be manipulated makes it difficult to determine the optimal resistance training program. Objective. The purpose of this investigation was to examine the effects of an 8-week resistance training intervention on strength and function in persons with PD. Methods. Eighteen men and women were randomized to training or standard care for the 8-week intervention. The training group performed 3 sets of 5–8 repetitions of the leg press, leg curl, and calf press twice weekly. Tests included leg press strength relative to body mass, timed up-and-go, six-minute walk, and Activities-specific Balance Confidence questionnaire. Results. There was a significant group-by-time effect for maximum leg press strength relative to body mass, with the training group significantly increasing their maximum relative strength (P < .05). No other significant interactions were noted (P > .05). Conclusions. Moderate volume, high-load weight training is effective for increasing lower-body strength in persons with PD.