INTRODUCTION End-stage renal disease is a serious public health issue. The objective of this retrospective cohort study was to assess the association between hemodialysis and cognitive impairment, while controlling for age, sex, residence, and comorbidities. METHODS This study assesses the risk of cognitive impairment among a nationwide cohort of new hemodialysis patients derived from the NHIRD. RESULTS A total of 4330 patients were assigned to the dialysis group and 17 320 patients were assigned to the control group. A total of 2103 of the patients developed cognitive impairment within 2 years after the date of dialysis initiation. Patients who developed cognitive impairment were older (69.85 ± 11.56) than their counterparts who did not develop cognitive impairment (58.58 ± 14.77; P