Recurrent falls in Parkinson’s disease after one year of follow-up: A nested case-control study

• Single fallers tend to fall indoors, while recurrent fallers fall outdoors.
• There were no differences in outcome between indoor and outdoor fallers.
• A higher level of motor disability was associated with recurrent falling.

The aims of this study were to compare clinical and fall characteristics of single and recurrent falls among persons with PD and to evaluate factors associated with recurrent falls. A total of 120 consecutive persons with PD, who denied having fallen in the past 6 months, were recruited. Occurrence of falling was registered during one year. Each person was given a “fall diary” with the aim at writing characteristics of the fall and contacted by telephone each month. Over one year of follow-up 42 persons with PD (35.0%) reported falling. Of 42 persons, 19 (45.2%) went on to become single and 23 (54.8%) went on to become recurrent fallers. Indoor falls were more common among single fallers, whilst outdoor falls were more common among recurrent fallers (p = 0.017). Slipping and freezing of gait was more common among single fallers (p = 0.035 and p = 0.024, respectively). Lower extremity weakness was more frequent among recurrent fallers (p = 0.023). The most common injury both among single and recurrent fallers was the soft-tissue contusion. The only factor associated with recurrent falling among persons with PD, who did not fall in past 6 months before the start of follow-up, was worse motor performance as measured by the UPDRS III score (odds ratio [OR] = 1.06, 95% confidence interval [CI] 1.01–1.11, p = 0.022). These results could be used in selection of persons with PD to enroll in fall prevention programs.