Post-stroke depression (PSD) is a frequent neuropsychiatric disorder following stroke which is associated with poor outcome. Neuronal Per-Arnt-Sim (PAS) domain protein 4 (Npas4) is associated with cognitive function. Npas4 expression in peripheral blood mononuclear cells (PBMCs) from patients with PSD was measured to find new therapeutic strategy.

Ischemic stroke patients (n = 152) within 1 week of stroke onset were recruited. At 3 months follow-up, the patients were divided into a PSD group (n = 77) and a stroke group (n = 75) using the Hamilton Rating Scale. Healthy subjects (n = 75) were also recruited in the study. The PSD group received 12 weeks of duloxetine treatment. Cognitive function was evaluated using the P300 test. Npas4 expression in PBMCs was measured by quantitative RT-PCR (qPCR).

Before treatment, P300 latencies in the PSD group were prolonged and the P300 amplitudes were lower than the control group (P < 0.01). Npas4 expression in the PSD group was also lower than the control group (P < 0.01). After treatment, the P300 latencies were reduced and the amplitudes were significantly elevated in the PSD group compared to that before treatment (P < 0.01). Meanwhile, Npas4 levels were significantly higher than that before treatment (P < 0.01). Npas4 expression was positively correlated to the P300 amplitudes (P < 0.05).

Changes of Npas4 expression in PBMCs are associated with cognitive impairment in PSD patients and new therapeutic options applying Npas4-related transcript mechanism could be considered in the future.