Indoor and outdoor falls in persons with Parkinson's disease after 1 year follow-up study: differences and consequences.

Falls among persons with Parkinson's disease (PD) often result in activity limitations, participation restrictions, social isolation or premature mortality. The purpose of this 1-year follow-up study was to compare potential differences in features of PD attributing to falls in relation to fall location (outdoor vs. indoor). We recruited 120 consecutive persons with PD who denied having fallen in the past 6 months. Disease stage and severity was assessed using the Hoehn and Yahr scale and the newer version of the Unified Parkinson's Disease Rating Scale. Occurrence of falling and characteristics of falls was followed for 1 year. Results were assessed statistically. Outdoor falls were more commonly preceded by the extrinsic factors (tripping and slipping). Slipping was more common outdoors (p = 0.001). Indoor falls were mostly preceded by the intrinsic factors (postural instability, lower extremity weakness, vertigo). Vertigo was more common indoors (p = 0.006). Occurrence of injuries was more common after outdoor falls (p = 0.001). Indoor falls resulted in contusions only, while outdoor falls resulted in lacerations and fractures as well. In the regression model adjusted for age, disease duration, on/off phase during fall, Hoehn and Yahr stage of disease and levodopa dosage, slipping was associated with outdoor falling (odds ratio = 17.25, 95 % confidence interval 3.33-89.20, p = 0.001). These findings could be used to tailor fall prevention program with emphasis on balance recovery and negotiation of objects in environment.