The impact of stroke on cognitive processing - a prospective event-related potential study.

BACKGROUND AND PURPOSE

Stroke is often associated with cognitive decline which can be evaluated by event-related potentials (ERP). So far, only little is known about the impact of stroke on ERP. The aim of this prospective study was to follow-up ERP latencies in stroke patients and to evaluate the influence of sex, vascular territory of stroke, reinfarction, and secondary prevention (acetylsalicylic acid versus piracetam).

METHODS

Visually evoked ERP were recorded in 563 stroke patients at baseline (i.e., within four weeks after stroke), after 12 months, and after 24 months. The latencies of the P2, N2, and P3 components were assessed and compared between different subgroups.

RESULTS

The P3 latency is initially more increased in female stroke patients, but shows a better recovery in women compared to men. A secondary prevention with piracetam leads to a significantly better recovery of ERP latencies than a treatment with acetylsalicylic acid. Data suggests a better recovery of left hemispheric infarction compared to right hemispheric infarction. Patients, who suffered another stroke during the follow-up period, showed a prolongation of P3 latency, suggesting an increased P3 latency to be associated with reinfarction.

CONCLUSIONS

Our results suggest that ERP measurement is an appropriate method for diagnosis and follow-up of cognitive changes after ischemic stroke. In particular the P3 component is an indicator for patients at risk for reinfarction.