A 9-Year Comparison of Dementia Prevalence in Korea: Results of NaSDEK 2008 and 2017
Seung Wan Suh, You Joung Kim, Kyung Phil Kwak, Kiwon Kim, Moon-Doo Kim, Byung‐Soo Kim, Bong‐Jo Kim, Shin Gyeom Kim, Jeong Lan Kim, Tae Hui Kim, Seok Woo Moon, Kyung Won Park, Jong‐Il Park, Joon Hyuk Park, Jae Nam Bae, Ji-Yeong Seo, Su Jeong Seong, Sang Joon Son, Il‐Seon Shin, Seung‐Ho Ryu, Kang Joon Lee, Nam-Jin Lee, Dong Young Lee, Dong Woo Lee, Seok Bum Lee, Chang Uk Lee, Sung Man Chang, Hyun‐Ghang Jeong, Maeng Je Cho, Seong‐Jin Cho, Jin Hyeong Jhoo, Young Min Choe, Ji Won Han, Ki Woong Kim
Abstract
BACKGROUND: In many high-income Western countries, the prevalence of dementia had been reduced over the past decades. OBJECTIVE: We investigated whether the prevalence of all-cause dementia, Alzheimer's disease, vascular dementia, and mild cognitive impairment (MCI) had changed in Korea from 2008 to 2017. METHODS: Nationwide Survey on Dementia Epidemiology of Korea (NaSDEK) in 2008 and 2017 was conducted on representative elderly populations that were randomly sampled across South Korea. Both surveys employed a two-stage design (screening and diagnostic phases) and diagnosed dementia and MCI according to the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders and the consensus criteria from the International Working Group, respectively. The numbers of participants aged 65 years or older in the screening and diagnostic phases were 6,141 and 1,673 in the NaSDEK 2008 and 2,972 and 474 in the NaSDEK 2017, respectively. RESULTS: The age- and sex-standardized prevalence of all-cause dementia and Alzheimer's disease showed nonsignificant decrease (12.3% to 9.8%, odds ratio [OR] = 0.89, 95% confidence interval [CI] = 0.54-1.48 for all-cause dementia; 7.6% to 6.8%, OR [95% CI] = 0.91 [0.58-1.42] for Alzheimer's disease). Vascular dementia decreased in the young-old population aged less than 75 years (2.7% to 0.001%, OR [95% CI] = 0.04 [0.01-0.15]) and in women (1.9% to 0.5%, OR [95% CI] = 0.27 [0.10-0.72]) while MCI remained stable (25.3% to 26.2%, OR [95% CI] = 1.08 [0.67-1.73]). CONCLUSION: We found that the prevalence of dementia in Korea showed a nonsignificant decrease between 2008 and 2017.