Association between thiamine decrease and neuropsychiatric symptoms in gastrointestinal and hematological cancer patients receiving chemotherapy

Clinical evidence of thiamine-related neuropsychiatric symptoms, including the initial stage, is limited because serum thiamine levels tend to be evaluated only for patients who develop severe neuropsychiatric symptoms suspected to be related to severe thiamine deficiency. This study aimed to evaluate the relationship between thiamine decline and neuropsychiatric symptoms, including initial symptoms, and the effect of chemotherapy on serum thiamine levels in gastrointestinal and hematological cancer patients receiving chemotherapy. We retrospectively identified 87 patients who were diagnosed with gastrointestinal and hematological cancers at our hospital. We evaluated the risk factors associated with neuropsychiatric symptoms, including initial symptoms (neuropsychiatric symptoms), the relationship between the presence of neuropsychiatric symptoms and serum thiamine levels, and changes in serum thiamine levels after chemotherapy. Logistic regression analysis identified thiamine decline as a significant factor associated with neuropsychiatric symptoms (p