Skip to content

Takahiro A Kato

Department of Psychiatry, Hokkaido University Graduate School of Medicine, Hokkaido, Japan.

2 papers in the library · 1 citation · publishing 2025

Papers

Acute and long-term effects of repeated ketamine infusions in treatment-resistant depression and associated metabolite changes.

Psychiatry and clinical neurosciences July 15, 2025 Hitoshi Sakurai, Daiki Setoyama, Takahiro A Kato et al. 1 citation

In an open-label study of 30 patients with treatment-resistant depression, four intravenous ketamine infusions (0.5 mg/kg) over two weeks rapidly reduced depression severity: the average Montgomery-Åsberg Depression Rating Scale score fell from 30.6 to 20.3 after the fourth infusion, and 26.7% of participants achieved remission. However, only 13.3% remained in remission at 12 months. Early changes in the metabolite 3-hydroxybutyrate predicted the degree of improvement both after the fourth infusion and at 12 months, suggesting it could serve as a biomarker for treatment response. The findings point toward more individualized use of ketamine infusions.

Psychosis induced by invocation presenting as possession state: A case of Kitousei-Seishinbyo still emerging in modern Japan.

PCN reports : psychiatry and clinical neurosciences December 1, 2025 Fumiya Miyano, Nobuyuki Mitsui, Yutaka Fujii et al.

A woman in her 50s with no prior psychiatric history developed possession-like symptoms—trance states, altered voices, and personality changes—after a fortune-teller told her that her misfortunes were caused by the spirit of her aborted child. She was hospitalized involuntarily. Medical tests were normal. Her symptoms fluctuated with spiritual contact and included mutism, rigidity, and somatic complaints. Psychosocial stressors such as marital discord and caregiving burden were identified. Treatment with family psychoeducation, occupational therapy, and low-dose psychotropics (tandospirone and zolpidem) led to gradual stabilization. She voluntarily stopped spiritual practices and was discharged after 62 days with sustained recovery. This case illustrates a modern example of Kitousei-Seishinbyo, a culture-bound syndrome first described in 1915, triggered by a fortune-teller.