Relationship Between Orthostatic Hypotension and Cognitive Functions in Multiple System Atrophy: A Longitudinal Study

Area of Science:

• Neurology
• Neuroscience
• Gerontology

Background:

• Multiple system atrophy (MSA) is a progressive neurodegenerative disorder.
• Orthostatic hypotension (OH) is a common comorbidity in MSA, potentially affecting brain function.
• The longitudinal impact of OH on cognitive trajectories in MSA remains incompletely understood.

Purpose of the Study:

• To investigate the effect of orthostatic hypotension (OH) on cognitive functions in patients with multiple system atrophy (MSA).
• To analyze the longitudinal changes in cognitive status in MSA patients with and without OH over a 24-month period.

Main Methods:

• Thirty-two MSA patients were assessed using a comprehensive neuropsychological battery at baseline (T0), 12 months (T1), and 24 months (T2).
• Orthostatic hypotension was diagnosed at baseline using an orthostatic standing test.
• Cognitive performance changes were compared between patients with and without OH using statistical analyses, including Mann-Whitney's U-test.

Main Results:

• At baseline, patients with OH showed better performance on word repetition tasks.
• By T1, patients with OH performed worse on semantic association tasks, and by T2, on the Stroop test-error effect.
• A significantly higher percentage of patients with OH (93%) experienced worsened cognitive status at T1 compared to those without OH (59%). OH, age, education, and baseline MOCA score predicted cognitive decline.

Conclusions:

• Orthostatic hypotension is a significant predictor of cognitive status worsening in MSA patients over a 1-year follow-up.
• The presence of OH is associated with accelerated cognitive decline in MSA.
• Longitudinal studies utilizing clinical categories (normal cognition, MCI, dementia) are recommended for further clarification of OH's role in MSA cognitive dysfunction.