THE USE OF POSTUROGRAPHY TO DISTINGUISH BETWEEN FALLERS AND NON-FALLERS IN A PARKINSON’S DISEASE POPULATION

Abstract

Static posturography has been used to identify fallers and non-fallers but it is not clear whether this test can discriminate between fallers and non-fallers in adults with Parkinson’s disease (PD). The conditions under which static posturography should be assessed in this population is also unclear. PURPOSE: To investigate the use of posturography and the test conditions to discriminate between fallers and non-fallers. METHODS: Twenty-six PD patients (H&Y: 1-3) participated in this preliminary study (14 fallers and 12 non-fallers). Posturographic analysis was carried out using a baropodometric platform. The posturographic analysis were performed under four different conditions: bipedal stance with eyes open (EO) and eyes closed (EC), bipedal stance with eyes open under dual task condition (counting backwards from 100) (EO-DT) and eyes closed under dual task condition (EC-DT). The total excursion (TE), the area (A) and the mean velocity (MV) of the centre of pressure were used to detect alterations in body sway. Groups comparisons were made using the Mann-Whitney U test. The ROC analysis was used to measure the accuracy of the stabilometry variables to distinguish between groups. RESULTS: The non-fallers group had better baseline stabilometric values than fallers group (TE: 410.59 ± 113.49 vs 520.38 ± 113.49 mm; A: 86.16 ± 92.19 vs 143.11 ± 285.67 mm2; MV: 13.95 ± 3.90 vs 17.82 ± 5.74 mm/s). The stabilometric variables worsened when the test was performed under the EC condition and under the dual task conditions. However, there were only significant differences between groups for the TE and the MV variables under EO (p = 0.046 and p = 0.046, respectively) and EC condition (p = 0.045 and p = 0.047, respectively). The Area Under Curve (AUC) values were acceptable for the TE and the MV both under EO (0.726 and 0.732, respectively) and EC conditions (0.696 and 0.711, respectively). An AUC <0.50 was reported both EO-DT and EC-DT for all stabilometric variables. CONCLUSIONS: The static posturography performed under EO and EC conditions was sensitive to discriminate between fallers and non-fallers in a PD population. Despite the worsening in the stabilometric variables when the test was carried out under dual task condition, adding a simple cognitive task did not improve the discrimination power, in fact it was adversely affected.