Using the Downton index to predict those prone to falls in stroke rehabilitation

Falls are a major complication in inpatient stroke rehabilitation. An important issue in preventive strategies is the early identification of those at risk. This study aimed at assessing the fall-prediction accuracy of an easily administered fall risk index in stroke rehabilitation.

A consecutive series of 135 patients admitted to a geriatric stroke rehabilitation unit was studied. A score on the Downton fall risk index was obtained from the admission assessment data and used as a predictive indicator of the risk of falls. The patients' falls were prospectively recorded during their rehabilitation stay. The correlation between falls and the predicted risk was assessed by means of survival analysis and a multiple regression analysis, adjusting for the time of observation.

The risk of falls as a function of the time observed was significantly greater among those predicted to be at high risk (index score > or = 3) than among the others (P = .009, log-rank test; odds ratio, 2.9). Furthermore, the number of falls during rehabilitation stay was moderately correlated (R = .57) with the fall risk index sum when adjusted as for the time of observation. The sensitivity of the fall prediction as to outcome was 91%, whereas the specificity was limited to 27%.

A moderately high correlation was found between the predicted and the observed risk of falls in stroke rehabilitation when the Downton fall risk index was used. However, a low specificity rate limits the accuracy of the prediction.