AUTHOR=Maycas-Cepeda Teresa , López-Ruiz Pedro , Feliz-Feliz Cici , Gómez-Vicente Lidia , García-Cobos Rocío , Arroyo Rafael , García-Ruiz Pedro J. 

TITLE=Hypomimia in Parkinson's Disease: What Is It Telling Us?

JOURNAL=Frontiers in Neurology

VOLUME=Volume 11 - 2020

YEAR=2021

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2020.603582

DOI=10.3389/fneur.2020.603582

ISSN=1664-2295

ABSTRACT=Introduction: Amimia is one of the most typical features of Parkinson´s disease (PD). However, its significance and correlation with motor and non-motor symptoms is unknown. The aim of this study was to evaluate the association between amimia and motor and non-motor symptoms including cognitive status, depression and quality of life in PD patients. We also tested the blink rate as a potential tool for measuring objectively upper facial bradykinesia.
Methods: We prospectively studied amimia in PD patients. Clinical evaluation was performed using the Unified Parkinson´s Disease Rating Scale (UPDRS) and timed tests.  Cognitive status, depression and quality of life were assessed using the Parkinson´s Disease cognitive Rating scale (PD- CRS), the 16-Item Quick Inventory of Depressive Symptomatology (QIDS-SR16) and the PDQ-39, respectively. Amimia was clinically evaluated according to item 19 of UPDRS III. Finally, we studied upper facial amimia by measuring resting blink frequency and blink rate during spontaneous conversation. 
Results: We included 75 patients. Amimia (item 19 UPDRS III) correlated with motor and total UPDRS (r: 0.529 and 0.551 Spearman), and its rigidity, distal bradykinesia and motor axial sub-scores (r:0.472; r:0.252 and r:0.508 respectively); Hoehn and Yahr scale (r: 0.392), timed tests, gait freezing, cognitive status (r: 0.29) and quality of life (r: 0.268) correlated with amimia. Blinking frequency correlated with amimia (measured with item 19 UPDRS), motor and total UPDRS.  
Conclusion: Amimia correlates with motor (especially axial symptoms) and cognitive situation in PD. Amimia could be a useful global marker of overall disease severity, including cognitive decline