Identification of modified dynamic gait index cutoff scores for assessing fall risk in people with Parkinson disease, stroke and multiple sclerosis.

ABSTRACT

BACKGROUND: Balance and gait impairments increase fall rate and injury in people with neurological disorders(PwND). The modified Dynamic Gait Index(mDGI) is a scale assessing dynamic balance during walking, however its ability in identifying Fallers and Recurrent Fallers has not been studied. RESEARCH QUESTION To evaluate mDGI's ability in identifying retrospective Fallers and Recurrent Fallers establishing cut-off scores for its use in clinical practice. METHOD: In this cross-sectional study, the number of retrospective falls and mDGI scores were collected. PwND were categorised as Non-Fallers or Fallers (falls≥1) and as Recurrent Fallers(falls≥2) or Non-Recurrent/Non-Fallers(falls<2) according to their number of retrospective falls over two months. Two generalised linear logistic models were developed using a machine learning method to detect Fallers (Model 1) and Recurrent Fallers (Model 2) based on mDGI scores. ROC curves were used to identify mDGI cut-off scores to distinguish between different fall categories. RESULTS: 58 PwND (mean ± standard deviation age 63.4 ± 12 years) including 28 people with Multiple Sclerosis, 15 people with Parkinson's disease and 15 people with Stroke were analysed. The mDGI score(median (IQR)) for Non-Fallers, Fallers, Recurrent Fallers and Non-Recurrent/Non-Fallers was respectively 50(22), 37(22), 26.5(20.25) and 46.5(20.5)points. The cut-off to identify Fallers from Non-Fallers was 49 points(sensitivity100 %, specificity50 %, post-test probability with mDGI ≤ cut-off 53.2 %, post-test probability with mDGI > cut-off 0%, AUC0.68), while 29 points(sensitivity60 %, specificity79 %, post-test probability with mDGI ≤ cut-off52.1 %, post-test probability with mDGI > cut-off16.1 %, AUC0.70) was the best cut-off to identify Recurrent Fallers. SIGNIFICANCE: People with mDGI score>49 points have low or minimal fall risk, while people with mDGI score≤49 points should be further investigated with other scales before starting a balance-focused rehabilitation intervention. People scoring ≤29 points on the mDGI scale may need a fall prevention intervention, regardless of the results of other balance clinical measures.