The Peking University team’s new discovery: Improve depression, may slow down the degradation of cognitive function, researcher Wu Xiang's comment

▎The content team editor of WuXi AppTec.
With the aging of the global population, the number of people suffering from cognitive impairment and dementia has increased significantly
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Early identification of high-risk groups of dementia and timely intervention are particularly important
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Depression is a risk factor for the onset of dementia, and its development process is variable
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But how this variability over time affects long-term changes in cognitive function is currently unclear
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Image source: 123RF October 2021, the relevant research results of the Peking University Clinical Research Institute team were published online in the top journal "Age and Ageing" in the field of geriatrics
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Studies have shown that in the elderly, keeping depression symptoms as low as possible may help alleviate the rate of cognitive decline
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We will attach the CES-D Depressive Symptom Evaluation Scale for reference in the following text
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The research was led by Zhu Yidan, an assistant researcher at the Institute of Clinical Research of Peking University, as the first author, and researcher Xie Wuxiang as the corresponding author
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The WuXi AppTec content team specially invited the corresponding author of the study, and researcher Xie Wuxiang from the Clinical Research Institute of Peking University commented on the results of the study
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Expert Interpretation Q This study uses data from community populations in the United States and the United Kingdom.
What is the background for selecting these data? This study is actually a continuation of our previous study (Persistent depressive symptoms and cognitive decline in olderadults.
British Journal of Psychiatry 2018;213:638-644).
When I was working at Imperial College in the UK, based on the analysis of the British ELSA cohort data, I found : Elderly people with persistent depressive symptoms will have an accelerated decline in cognitive function
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This study further found that elderly people who have maintained no depressive symptoms and those who have gradually improved depressive symptoms have the slowest decline in cognitive function
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This result was not only found in the ELSA cohort, but also repeatedly verified in another large prospective cohort study, making this finding more reliable
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Q The research found that maintaining no depressive symptoms and actively improving depressive symptoms are associated with a slower rate of cognitive decline.
What guiding significance does this research result have for clinical practice? Our research is observational research, and care should be taken when interpreting the results
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The results of this study provide an intervention target for the prevention and treatment of mild cognitive impairment or dementia in the future
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However, whether the treatment and improvement of depression can really alleviate the decline in cognitive function or even improve the cognitive function of patients still needs to be confirmed by randomized controlled trials
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Source of screenshots of research introduction: Age and Ageing This study uses data from a total of 17,556 community populations in the US HRS cohort and the British ELSA cohort to explore the relationship between the trajectory of different depression symptoms and the subsequent decline in cognitive function for up to 18 years
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Both cohorts used the Center for Epidemiological Research Depression Scale (CES-D) to assess the severity of depression in the elderly
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There are 8 items in this scale, each item represents a state, the score is 1 or 0, a total of 8 points, the higher the score, the more serious the depressive symptoms, the score ≥ 4 points, the presence of depressive symptoms
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▲Epidemiology Research Center Depression Scale (CES-D) Evaluation (Source: Reference [1]) The study is based on a total of 4 depressive symptoms evaluated by the CES-D scale in 8 years, using a group trajectory model (GBTM ) To calculate the depression trajectory changes, and divide the population’s depressive symptoms trajectory changes into 5 categories, namely "no depression", "low depression symptoms", "aggravated depressive symptoms", "improvement of depressive symptoms" and "sustained depression"
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In the following years (HRS: 18 years; ELSA: 10 years), in the follow-up of the overall cognitive function and memory, executive function and time orientation of the three subdivided cognitive domains, this study found the same in the two cohorts The results of the meta-merger
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▲The depressive symptom trajectory that has been determined in HRS (A) and ELSA (B), the higher the CES-D score, the more severe the depression
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Each color represents a type of depressive symptom trajectory (picture source: reference [1]) The results of the study found that compared with the no depression group, the cognitive function decline of the severe depressive symptom group and the persistent depression group was significantly faster; even if it is mild Depressive symptoms are also associated with a faster decline in cognitive function
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However, the researchers did not find this association in the group of improving depressive symptoms.
That is to say, those people whose depressive symptoms were severe at first but improved, the cognitive function does not decline rapidly over time
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▲In the HRS (A) and ELSA (B) cohorts, the trajectory of depression symptoms and later cognitive decline in the elderly
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The worsening depressive symptoms group (red line), persistent depression group (grey line), and mild depression group (yellow line) had a faster decline in cognitive function
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(Image source: Reference [1]) Conclusion This study reveals that in the elderly population living in the community, different degrees of depressive symptoms have different effects on later cognitive decline
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At the same time, it also reminds us that as far as possible to maintain depression symptoms at a low level, it may alleviate the problem of cognitive decline in the elderly
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The expert introduced Dr.
Xie Wuxiang, researcher and doctoral supervisor
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Peking University School of Public Health received a bachelor's degree in preventive medicine and a doctorate in epidemiology and health statistics
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He used to be engaged in clinical research on cardiovascular diseases in Beijing Anzhen Hospital
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Postdoctoral Fellow in Epidemiology and Biostatistics at Imperial College, UK, funded researcher, Newton International Scholar of British Academy of Medical Sciences
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In October 2017, he joined the Clinical Research Institute of Peking University
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He has been engaged in the clinical research of heart and brain diseases for a long time, and has published 35 academic papers in this field as the first or corresponding author, of which 30 are included in SCI
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Currently serving as a member of the editorial board of several journals
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Member and Secretary of the Health Risk Assessment and Control Professional Committee of the Chinese Preventive Medicine Association, Member of the Maternal and Infant Cardiovascular Structure and Metabolism Professional Committee of the Chinese Association of Prenatal and Childcare, Member of the Chronic Disease Management Branch of the Chinese Association of Non-Public Medical Institutions, Beijing Medical Association Clinical Epidemiology and Evidence-based Medical Branch Youth Committee and so on
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References[1] Yidan Zhu, Chenglong Li,Wuxiang Xie, et al.
(2021).
Trajectories of depressive symptoms and subsequent cognitive decline in older adults: a pooled analysis of two longitudinalcohorts, Age and Ageing;, afab191, from https:/ /doi.
org/10.
1093/ageing/afab191 Disclaimer: WuXi AppTec's content team focuses on introducing global biomedical health research progress
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This article is for the purpose of information exchange only.
The opinions expressed in the article do not represent the position of WuXi AppTec, nor does it mean that WuXi AppTec supports or opposes the views in the article
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This article is not a treatment recommendation either
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If you need guidance on treatment plans, please go to a regular hospital for treatment
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