A population-based study was designed to evaluate the clinical associates of postural sway and to identify the risk factors for falls in Parkinson's disease (PD). From a total population of 205,000 inhabitants, 215 PD patients were identified of which 120 home-dwelling cases were finally included in the study. Medical data were collected and patients were clinically examined and tested for static balance using an inclinometric device. Recent falls occurred in 40 (33%) of the subjects and 27 (23%) subjects were recurrent fallers. The fallers had a significantly larger sway area (P = 0.021) and a larger maximum deflection in anterior-posterior (P = 0.016) and lateral directions (P = 0.006) than the nonfallers. A significant correlation was found between the sway measures and the UPDRS total score, motor subcore and UPDRS "bradykinesia" item. A higher UPDRS total score (OR: 1.04, 95% CI: 1.01-1.07) and an increased sway area (OR: 1.25, 95% CI: 1.02-1.54) were independent risk factors for recent falling in PD. In addition, the duration and severity of PD, antiparkinsonian medication, recent falling and the use of a walking aid were associated with increased sway measures. The results can be used to identify PD patients who are at a risk of falling. Both antiparkinsonian medication and nonmedical treatment should be optimized to reduce falls in PD.

History of falling and disease severity indicate increased risk of recurrent falls in PD, while patients with slow walking speed may have an increased risk of mortality. Recurrent falling was not associated with increased risk of mortality in PD in this study.

Orthostatic hypotension (OH) is a common feature in Parkinson's disease (PD). As the control of balance and gait is already affected by PD per se, OH may further predispose patients to falls and accidents. The study was conducted to evaluate the clinical correlates of OH and its association with mobility and balance in PD. From a total population of 205,000 inhabitants, 120 PD patients were included in the study. Medical data including history of recent falls were collected, and patients were clinically examined using the orthostatic test, the Timed Up & Go test, walking speed, and the quantitative measurement of postural sway. Sixty-three (52.5%) patients had OH in the orthostatic test. Twenty-five (39.5%) patients with and 16 (28.1%) patients without OH (P = 0.614) had fallen during the past 3 months. Patients with OH had significantly increased postural sway in standing compared with patients without OH. However, OH was not associated with mobility or walking speed. The current results support the concept that the control of body balance and OH may be closely linked.

Advanced age and severity of the disease are related to impaired mobility and balance in PD patients. The severity of the disease and increased postural sway seem to be the most important independent risk factors for falling in PD.