Dear Editor,The association between proton pump inhibitor (PPI) use and dementia is controversial [1]. In this issue of Drug Safety, Imfeld et al.[2] reported as follows: "As compared to non-use, long-term PPI use (≥ 100 prescriptions) was not associated with an increased risk of developing AD (Alzheimer's disease) [aOR (adjusted odds ratio) 0.88, 95% CI (confidence interval) 0.80-0.97] or VaD (vascular dementia) (aOR 1.18, 95% CI 1.04-1.33)" [2]. I am afraid that long-term PPI use (≥ 100 prescriptions) was associated with an increased risk of developing VaD (aOR 1.18, 95% CI 1.04-1.33) as compared to non-use based on the results, because the 95% CI was between 1.04 and 1.33.