Clinical aspects of hypomimia in Parkinson’s disease

BACKGROUND. Hypomimia is a distinct symptom of Parkinsons disease manifested by reduced facial expression and slowness of movement in mimic muscles. Clinical aspects of this symptom remain underinvestigated to the date. AIM. Based on correlation analysis, to determine the association between hypomimia, general manifestations of hypokinesia and the quality of life in patients with Parkinsons disease as well as to evaluate the influence of therapy with L-DOPA pharmaceuticals on hypomimia. MATERIAL AND METHODS. Clinical aspects of hypomimia were studied in 30 patients with stage 1.53.0 PD according to Hoehn and Yahr Rating Scale. The mean age of the patients was 69. Analysis of hypomimia was carried out using a proprietary method of computer video-analysis of facial muscle movement in performance of 6 tests: smiling, drawing of the letter O, winking, eyebrow raising, frowning and text reading. The gait function was assessed using the laser analyser of kinematic parameters of gait. Mean step length, step time and gait velocity were evaluated. Manifestations of general hypokinesia were analysed via the Unified Parkinsons Disease Rating Scale licensed by the International Parkinson and Movement Disorder Society. Statistical processing of the data was performed using the IBM SPSS Statistics 23 software package. The Wilcoxon test and the Spearmans correlation coefficient were used. The statistical significance level was set at p 0.05. RESULTS. The correlation between the degree of hypomimia and the severity of general hypokinesia has been confirmed, which determines the prospect in objective analysis of mimics as a possible screening test for general hypokinesia. We have obtained data confirming the association between hypomimia and general hypokinesia: in particular, step time, step length and gait velocity. CONCLUSION. While using the proprietary method of objective hypomimia diagnosis, we have revealed the presence of correlation between manifestations of hypomimia and general hypokinesia. Additionally, manifestations of hypomimia have been found to decrease against the background of dopaminergic therapy.