Extrapyramidal symptoms predict cognitive performance after first-episode psychosis

Area of Science:

• Neuroscience
• Psychiatry
• Clinical Psychology

Background:

• Extrapyramidal (EP) symptoms, including tremor, rigidity, and bradykinesia, are frequent side effects of antipsychotic medications.
• These symptoms are often associated with impaired neurocognitive functioning.

Purpose of the Study:

• To investigate the relationship between EP symptoms and neurocognitive performance in individuals with first-episode psychosis (FEP).
• To determine if EP symptoms predict longitudinal changes in cognitive function.

Main Methods:

• Assessed EP symptoms (Simpson-Angus Scale) and cognitive function at baseline and 12-month follow-up in 113 FEP patients.
• Utilized linear regression models, controlling for symptom levels and medication dosage (chlorpromazine equivalents).

Main Results:

• 40% of participants had mild EP symptoms at treatment onset.
• EP symptoms were associated with lower baseline and follow-up neurocognitive performance, particularly in processing speed tasks for nonaffective disorders.
• Baseline EP symptoms longitudinally predicted global, verbal, and visuomotor cognition, even after controlling for other factors.

Conclusions:

• EP symptoms, even mild ones, are associated with both cross-sectional and longitudinal neurocognitive impairments in early psychosis.
• Absence of EP symptoms at treatment initiation correlates with better cognitive outcomes.
• EP symptoms may serve as early indicators of sustained neurocognitive deficits in psychosis.