Xiaoniu Liang1,2, Ding Ding3,4, Qianhua Zhao1,2, Wanqing Wu1,2, Zhenxu Xiao1,2, Jianfeng Luo5,6, Zhen Hong1,2. 1. Institute of Neurology, Huashan Hospital, Fudan University, Shanghai, China. 2. National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China. 3. Institute of Neurology, Huashan Hospital, Fudan University, Shanghai, China, dingding@huashan.org.cn. 4. National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China, dingding@huashan.org.cn. 5. Department of Biostatistics, School of Public Health, Fudan University, Shanghai, China. 6. The Key Laboratory of Public Health Safety of Ministry of Education, Shanghai, China.
Abstract
BACKGROUND: A few studies have demonstrated the association of poorer olfactory identification (OI) with poorer cognition in population-based cohorts. None of them considered the outcome associated with the inability to smell a certain odor. OBJECTIVE: To verify the hypothesis that at least one specific odor is associated with incident cognitive decline among older adults. METHODS: In the Shanghai Aging Study, a sub-cohort of 948 dementia-free participants who had baseline OI measurements were prospectively followed for 5 years. RESULTS: An inability to smell peppermint (β = -0.44, p < 0.001), rose (β = -0.14, p = 0.040), or coffee (β = -0.37, p = 0.002) was inversely related to the annual rate of change in the Mini Mental State Examination score, and an inability to smell peppermint was associated with a higher risk for incident dementia (hazard ratio 2.67, 95% CI 1.44-4.96) after adjustment for confounders. CONCLUSION: Our study suggests that some odors, especially peppermint, might be considered as a potential predictor for dementia in older populations.
BACKGROUND: A few studies have demonstrated the association of poorer olfactory identification (OI) with poorer cognition in population-based cohorts. None of them considered the outcome associated with the inability to smell a certain odor. OBJECTIVE: To verify the hypothesis that at least one specific odor is associated with incident cognitive decline among older adults. METHODS: In the Shanghai Aging Study, a sub-cohort of 948 dementia-free participants who had baseline OI measurements were prospectively followed for 5 years. RESULTS: An inability to smell peppermint (β = -0.44, p < 0.001), rose (β = -0.14, p = 0.040), or coffee (β = -0.37, p = 0.002) was inversely related to the annual rate of change in the Mini Mental State Examination score, and an inability to smell peppermint was associated with a higher risk for incident dementia (hazard ratio 2.67, 95% CI 1.44-4.96) after adjustment for confounders. CONCLUSION: Our study suggests that some odors, especially peppermint, might be considered as a potential predictor for dementia in older populations.