Association of post-stroke delirium with short-term trajectories of cognition

Background: Delirium could increase the risk of cognitive decline. We aimed to determine if changes in cognitive functions shortly after stroke differ between patients with and patients without delirium. Methods: We included patients who participated in the Prospective Observational Polish Study on post-stroke delirium and underwent the Montreal Cognitive Assessment (MoCA) at day 1, day 8 and 3 months after stroke. Delirium was diagnosed using DSM-5 criteria. We used mixed linear regression models to characterize changes in mean adjusted MoCA scores over time. Results: We included 402 patients (mean age: 68.9 +/- 13.3 years; mean NIHSS on admission: 6.2 +/- 5.5; 48.8 % female). Delirium occurred in 18.9 % of them. Mean adjusted MoCA scores increased from day 1 to day 8 (20.48 vs 23.34, P <0.001) and then declined from day 8 to month 3 (23.34 vs 22.21, P < 0.001). The rate of change in total MoCA scores from day 1 to day 8 (net effect: 0.65, 95 %CI: -1.19; 2.49, P = 0.489) and from day 8 to month 3 (net effect: -2.43, 95 %CI: -4.84; -0.02, P = 0.147) did not differ between patients with and patients without delirium. Compared with patients without delirium, those with delirium showed a greater improvement in naming, orientation and attention, accompanied by a worsening in memory from day 1 to day 8. They also experienced a greater decline in attention and orientation, along with a greater improvement in memory from day 8 to 3 months. Conclusions: Post-stroke delirium is associated with short-term trajectories of specific cognitive domains, but not with changes in global cognition.