Prevalence Rates of Dementia and Mild Cognitive Impairment Are Affected by the Diagnostic Parameter Changes for Neurocognitive Disorders in the DSM-5 in a Korean Population

Abstract

Aim: To examine the impact of the revised diagnostic criteria for neurocognitive disorders (NCDs) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) on the prevalence of dementia and mild cognitive impairment (MCI). Methods: A total of 755 participants aged 65 years or older in the Nationwide Survey on Dementia Epidemiology in Korea 2012 were rediagnosed according to the DSM-5 criteria. Results: The estimated age-, gender-, education-, and urbanicity-standardized prevalence rates of major and mild NCDs were 8.35 and 11.10%, respectively, and those of dementia and MCI were 8.74 and 31.85%, respectively. Cohen's κ for dementia and major NCD was 0.988, and that for MCI and mild NCD was 0.273. Conclusion: Diagnostic discrepancies between major/mild NCDs and dementia/MCI might depend on the operationalization of neuropsychological performance criteria.