Rocío Del Pino, Marian Acera, Ane Murueta-Goyena, Olaia Lucas-Jimenez, Natalia Ojeda, Naroa Ibarretxe-Bilbao, Javier Pena, Paula Reyero, Jesus M Cortes, Beatriz Tijero, Marta Galdos, Juan Carlos Gomez-Esteban, Inigo Gabilondo. Visual dysfunction is associated with cognitive impairment in Parkinson’s disease. Parkinsonism and Related Disorders 92: 22–25, 2021. article: [pdf]
Introduction: Visual dysfunction and cognitive impairment are common in Parkinson’s disease (PD) but the precise contribution of lower-level visual impairment to visual-input based cognitive performance has not been extensively characterized in PD. Methods: We included 49 PD patients and 22 healthy controls (HC). Lower-level visual function tests [high and low contrast visual acuity (HCVA and LCVA) and contrast sensitivity (CS)] and a neuropsychological battery (involving visual cognition) were performed. Pairwise correlations between lower-level visual functions and visual cognition were computed and stepwise linear regressions were fitted introducing age, Geriatric Depression Scale, and lower-level visual functions in the model to calculate their predicted effect on visual cognition. Results: Compared to controls, patients presented a significant impairment in all cognitive domains (visual attention, visual processing speed and visual perception, visuospatial abilities, visuoconstructive abilities, and visual memory), and lower-level visual functions. HCVA and LCVA were significantly associated with visual cognition in PD. HCVA explained up to 49.3% and 34.2% of the variability in visual perception and visuospatial abilities, respectively, whereas LCVA was mainly associated with short- and long-term visual memory and visuospatial abilities. Conclusion: Lower-level visual dysfunction is highly associated with cognitive performance in PD, when cognitive tests are based on visual input. Our results support that lower-level visual functions should be considered when assessing cognitive status of PD patients and might be useful for predicting cognitive deterioration.