February 04, 2021
Depressive symptoms and altered use of public transportation occurred a decade before diagnosis of late-onset Parkinson disease in a cohort of patients, according to a study published in Parkinsonism & Related Disorders.
“Thanks to the very long-term follow-up of the PAQUID population-based cohort [in France], we assessed trajectories of cognitive complaints and functioning over a 13-year period before the diagnosis of late-onset Parkinson disease,” researchers wrote.
Among 3777 people in the cohort, 43 developed Parkinson disease over follow-up. The average age at diagnosis was 78. Researchers matched participants who developed Parkinson disease with 86 older adults who served as control subjects and assessed scores measuring cognitive domains, daily function, and depressive symptoms over time.
Depressive symptoms occurred 12 years before Parkinson disease diagnosis, according to the study. Up to 3 years before diagnosis, global scores of instrumental activities of daily living also changed—with altered use of public transportation occurring 10 years before diagnosis. Psychomotor speed slowed notably 2 years before diagnosis.
However, researchers found no significant decline in global cognition before diagnosis.
“In late-onset Parkinson disease, while global cognitive functions seem preserved, psychomotor speed starts to decline 2 years before the diagnosis, and activities of daily living are also impacted,” they wrote. “Depressive symptoms appear very early in the prediagnostic phase.”
Foubert-Samier A, Helmer C, Le Goff M, et al. Cognitive and functional changes in prediagnostic phase of Parkinson disease: A population-based study [published online ahead of print, 2020 Aug 15]. Parkinsonism Relat Disord. 2020;79:40-46. doi:10.1016/j.parkreldis.2020.08.022