Early detection of cognitive impairment in patients with insulinoma

Purpose Long-standing hypoglycemia can cause cognitive impairment, and whether recurrent severe hypoglycemia impacts cognitive function in patients with insulinoma has not been studied. This study focused on exploring the cognitive function in patients with insulinoma. Methods A prospective study was conducted to assess cognitive function in patients with insulinoma by administering the Montreal Cognitive Assessment (MoCA) questionnaire between January 2016 and July 2017, and patients with cognitive impairment were followed up to undergo the MoCA test 1 year after surgery. The MoCA scores after surgery were compared with the scores before surgery, and the associations between cognitive impairment and relevant factors were further evaluated by multiple linear regression analysis. Results Eighteen out of thirty-four patients (53%) with insulinoma were screened positive for cognitive impairment as defined by a MoCA score <26. Performance in certain cognitive domains, including visuospatial and executive functions, delayed memory, attention, language, and abstraction, was significantly worse in patients with cognitive impairment. Multivariate analysis indicated that MoCA scores correlated significantly with tumor grade and years of education. Eight patients with cognitive impairment were lost to follow-up. The remaining ten patients with cognitive impairment showed improvements 1 year postoperatively, and seven patients recovered to normal cognitive function. Conclusions Cognitive impairment was found in patients with insulinoma and was reversible in some patients 1 year after surgery. More studies are needed to explore the underlying mechanisms of the existence and reversibility of cognitive impairment in patients with insulinoma.