Dementia rates in China are rising disproportionately

Rates of Alzheimer’s disease and other dementias are rising faster in China than in the rest of the world, driven in part by population growth, high blood sugar, smoking, and obesity

PLOS

Facebook

XLinkedIn
MessageWhatsAppEmail

 

image: 

Global burden of disease map for ADD, 1990-2021. Annual change in deaths per 100,000 people for all sexes and all ages

view more 

Credit: Liu, Geng., 2025, PLOS One, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

The burden of Alzheimer’s disease and other dementias in China is higher than in most countries and increasing at a faster rate than the global average, according to a new study published May 7, 2025 in the open-access journal PLOS One by Siyu Liu and Daoying Geng of Fudan University, China.

Alzheimer’s disease and other dementias (ADD) are an increasingly serious global health issue, with rates rising worldwide. There is currently a lack of understanding of the disease burden and risk factors of ADD specifically in China, despite being one of the countries with a rapidly aging population.

In the new study, the researchers analyzed more than three decades of global health data from the Global Burden of Disease (GBD), a public database jointly initiated by institutions including the World Bank and the World Health Organization. They found that between 1990 and 2021, ADD cases in China tripled, while global cases doubled. Women bear a higher overall disease burden, partly due to longer lifespans, but men have slightly higher death rates from the condition. The study also projected trends for the next 15 years using statistical models, suggesting that dementia rates will continue to rise, especially in China, unless more effective interventions are put in place.

When focusing on risk factors for ADD, the study showed that high blood sugar (from conditions like diabetes) is now the leading preventable risk factor for dementia worldwide, including in China. Smoking and high body weight are also major contributors, particularly among men.

The authors conclude that the increase in ADD in China is mostly being driven by population growth and shifting age demographics, but that efforts to reduce high blood sugar and smoking – especially among older adults – could slow the increase in dementia cases.

The authors add: “ADD is one of the diseases with the heaviest global disease burden. The disease burden of ADD in China and globally has increased year by year from 1990 to 2021.”

 

 

In your coverage, please use this URL to provide access to the freely available article in PLOS One: https://plos.io/3EDwBJo

Citation: Liu S, Geng D (2025) A systematic analysis for disease burden, risk factors, and trend projection of Alzheimer’s disease and other dementias in China and globally. PLoS ONE 20(5): e0322574. https://doi.org/10.1371/journal.pone.0322574

Author countries: China

Funding: The funding organization of the National Nature Science Foundation of China (82372048) is National Natural Science Foundation of China (NSFC). The funding organization of the Science and Technology Commission of Shanghai Municipality (22TS1400900, 23S31904100, 22ZR1409500, 24SF1904200, 24SF1904201) is Shanghai Municipal Science and Technology Commission. DG is the recipient of the funding awards listed above. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

---

Journal

PLOS One

DOI

10.1371/journal.pone.0322574 

Method of Research

Observational study

Subject of Research

People

Article Title

A systematic analysis for disease burden, risk factors, and trend projection of Alzheimer’s disease and other dementias in China and globally

Article Publication Date

7-May-2025

 

Are you curious? It might help you stay sharp as you age

New research shows questions you ask and interest in lifelong learning might protect against Alzheimer's disease

University of California - Los Angeles

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppAre you curious? It might help you stay sharp as you ageNew research shows questions you ask and interest in lifelong learning might protect against Alzheimer's disease
Peer-Reviewed PublicationUniversity of California - Los Angeles
FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmailWhat is the trick to aging successfully? If you’re curious about learning the answer, you might already be on the right track, according to an international team of psychologists including several from UCLA. Their research shows that some forms of curiosity can increase well into old age and suggests that older adults who maintain curiosity and want to learn new things relevant to their interests may be able to offset or even prevent Alzheimer’s disease. Conversely, those who show muted curiosity and disinterest may be at risk for dementia. The finding contradicts prior research that showed that curiosity decreases with age.
“The psychology literature shows that oftentimes what's known as trait curiosity, or a person’s general level of curiosity, tends to decline with age,” said UCLA psychologist Alan Castel, who is the senior author of a new paper published in the journal PLOS One. “But we thought that was a little bit strange and went against some of the things we saw in some of the older adult participants in our experiments, who would often be very engaged and interested in learning about memory, specifically, but even other forms of trivia.”
Castel and Mary Whatley, who led the research as a doctoral student at UCLA and is now an assistant professor of psychology at Western Carolina University, and colleagues Kou Murayama and Michiko Sakaki at the University of Tübingen and Kochi University of Technology, wondered if the answer lay in a different type of curiosity called state curiosity.
State curiosity is what psychologists call the kind of momentary feeling of curiosity people experience when they are asked about specific topics. Trait curiosity, on the other hand, is a personality trait. Some people, for example, might not be very inquisitive by nature, being content to accept things more or less at face value (trait curiosity), but have a passionate thirst for knowledge in specific topics or hobbies (state curiosity). All people possess varying degrees of both trait and state curiosity.
To tease apart the two types of curiosity, the researchers recruited a large sample of participants between the ages of 20 and 84, with an average age of 44, to complete an
online questionnaire designed to assess how curious they were in general, or their trait curiosity. Then, to test state curiosity, the researchers asked the participants to guess the answers to hard trivia questions that most people were unlikely to already know — e.g., What was the first country to give women the right to vote? The researchers asked people to guess an answer, then asked participants how interested they were to know the answer before showing the correct answer (if you are curious: New Zealand).
Analysis showed that the two kinds of curiosity are correlated: People who have more state curiosity also experience more trait curiosity, and vice versa. In general, trait curiosity did decline across the adult lifespan. However, the interest ratings people gave in learning new information from trivia — a measure of state curiosity — declined in early adulthood, then increased sharply after middle age and continued upward well into old age. The finding, Castel said, mirrors research that shows a dip in happiness in midlife.
One reason for the discrepancy, the researchers suggest, is that until middle age, people are usually interested in acquiring the knowledge, skills and opportunities they need to succeed at school and their jobs, pay mortgages and raise families, and thus a fairly high level of overall curiosity is needed. These obligations also come with stressors that could contribute to a decline in overall happiness. But as they age and gather this knowledge, they don’t need to allocate as many resources to trait curiosity. As their children leave home and they begin to retire, for example, people can indulge specific interests, and state curiosity increases.
“Our findings fit with some of my work on selectivity theory, which is that as we get older, we don’t want to stop learning, we’re just more selective about what we want to learn,” Castel said. “You see this in the context of lifelong learning: A lot of older adults will go back to take classes or pick up hobbies or engage in bird watching. I think it shows that this level of curiosity, if maintained, can really keep us sharp as we age.”
Castel said that his research on memory has shown that people tend to quickly forget information that doesn’t engage their curiosity.
“As we get older, maybe we want to be focused on the things that are important, and we forget the things that are less relevant,” Castel said. “Anecdotally, a lot of older adults I speak to say that it's important to stay curious. That fits with some of the research that shows that people who have early stages of dementia might show disinterest in things that they once enjoyed.”
This work was supported in part by the National Institutes of Health’s National Institute on Aging, the Leverhulme Trust and the Alexander von Humboldt Foundation.
JournalPLOS OnEmail

What is the trick to aging successfully? If you’re curious about learning the answer, you might already be on the right track, according to an international team of psychologists including several from UCLA. Their research shows that some forms of curiosity can increase well into old age and suggests that older adults who maintain curiosity and want to learn new things relevant to their interests may be able to offset or even prevent Alzheimer’s disease. Conversely, those who show muted curiosity and disinterest may be at risk for dementia. The finding contradicts prior research that showed that curiosity decreases with age.

“The psychology literature shows that oftentimes what's known as trait curiosity, or a person’s general level of curiosity, tends to decline with age,” said UCLA psychologist Alan Castel, who is the senior author of a new paper published in the journal PLOS One. “But we thought that was a little bit strange and went against some of the things we saw in some of the older adult participants in our experiments, who would often be very engaged and interested in learning about memory, specifically, but even other forms of trivia.”

Castel and Mary Whatley, who led the research as a doctoral student at UCLA and is now an assistant professor of psychology at Western Carolina University, and colleagues Kou Murayama and Michiko Sakaki at the University of Tübingen and Kochi University of Technology, wondered if the answer lay in a different type of curiosity called state curiosity.

State curiosity is what psychologists call the kind of momentary feeling of curiosity people experience when they are asked about specific topics. Trait curiosity, on the other hand, is a personality trait. Some people, for example, might not be very inquisitive by nature, being content to accept things more or less at face value (trait curiosity), but have a passionate thirst for knowledge in specific topics or hobbies (state curiosity). All people possess varying degrees of both trait and state curiosity.

To tease apart the two types of curiosity, the researchers recruited a large sample of participants between the ages of 20 and 84, with an average age of 44, to complete an

online questionnaire designed to assess how curious they were in general, or their trait curiosity. Then, to test state curiosity, the researchers asked the participants to guess the answers to hard trivia questions that most people were unlikely to already know — e.g., What was the first country to give women the right to vote? The researchers asked people to guess an answer, then asked participants how interested they were to know the answer before showing the correct answer (if you are curious: New Zealand).

Analysis showed that the two kinds of curiosity are correlated: People who have more state curiosity also experience more trait curiosity, and vice versa. In general, trait curiosity did decline across the adult lifespan. However, the interest ratings people gave in learning new information from trivia — a measure of state curiosity — declined in early adulthood, then increased sharply after middle age and continued upward well into old age. The finding, Castel said, mirrors research that shows a dip in happiness in midlife.

One reason for the discrepancy, the researchers suggest, is that until middle age, people are usually interested in acquiring the knowledge, skills and opportunities they need to succeed at school and their jobs, pay mortgages and raise families, and thus a fairly high level of overall curiosity is needed. These obligations also come with stressors that could contribute to a decline in overall happiness. But as they age and gather this knowledge, they don’t need to allocate as many resources to trait curiosity. As their children leave home and they begin to retire, for example, people can indulge specific interests, and state curiosity increases.

“Our findings fit with some of my work on selectivity theory, which is that as we get older, we don’t want to stop learning, we’re just more selective about what we want to learn,” Castel said. “You see this in the context of lifelong learning: A lot of older adults will go back to take classes or pick up hobbies or engage in bird watching. I think it shows that this level of curiosity, if maintained, can really keep us sharp as we age.”

Castel said that his research on memory has shown that people tend to quickly forget information that doesn’t engage their curiosity.

“As we get older, maybe we want to be focused on the things that are important, and we forget the things that are less relevant,” Castel said. “Anecdotally, a lot of older adults I speak to say that it's important to stay curious. That fits with some of the research that shows that people who have early stages of dementia might show disinterest in things that they once enjoyed.”

This work was supported in part by the National Institutes of Health’s National Institute on Aging, the Leverhulme Trust and the Alexander von Humboldt Foundation.

---

Journal

PLOS One

Although our general tendency to be curious may decrease with age, our situational or "state" curiosity might actually increase across the lifespan, which might help boost well-being and cognitive outcomes in older age

PLOS

Facebook

LinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Although our general tendency to be curious may decrease with age, our situational or "state" curiosity might actually increase across the lifespan.

view more 

Credit: Age Without Limits, CC0 (https://creativecommons.org/publicdomain/zero/1.0/)

Although our general tendency to be curious may decrease with age, our situational or "state" curiosity might actually increase across the lifespan, which might help boost well-being and cognitive outcomes in older age

Article URL: https://plos.io/3SatjAg

Article title: Curiosity across the adult lifespan: Age-related differences in state and trait curiosity

Author countries: U.S., Germany

Funding: National Institutes of Health (National Institute on Aging) Award Number R01AG044335 to AC: https://www.nia.nih.gov/ Leverhulme Trust Grant Number RL-2016-030 to KM: https://www.leverhulme.ac.uk/ Alexander von Humboldt Foundation Professorship to KM: https://www.humboldt-foundation.de/en/ No funders played a role in the study design, data collection, analysis, decision to publish, or preparation of the manuscript.

---

Journal

PLOS One

DOI

10.1371/journal.pone.0320600 

Article Title

Curiosity across the adult lifespan: Age-related differences in state and trait curiosity

Article Publication Date

7-May-2025

 

People displaying high problematic (excessive and dependent) social media use are more likely to engage with and believe fake news

PLOS

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

People displaying high problematic (excessive and dependent) social media use are more likely to engage with and believe fake news.

view more 

Credit: ROBIN WORRALL, Unsplash, CC0 (https://creativecommons.org/publicdomain/zero/1.0/)

People displaying high problematic (excessive and dependent) social media use are more likely to engage with and believe fake news

Article URL: https://plos.io/3EFkKKP

Article title: Problematic social media use is associated with believing in and engaging with fake news

Author countries: U.S.

Funding: DM and MDM received funding for this research from the Michigan State University Trifecta Initiative for Interdisciplinary Health Research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

---

Journal

PLOS One

DOI

10.1371/journal.pone.0321361 

Article Title

Problematic social media use is associated with believing in and engaging with fake news

Article Publication Date

7-May-2025

First-of-its-kind MSU study links problematic social media use to belief in fake news

Michigan State University

Facebook

XLinkedInWeChatBlueskyMessageWhatsApp]\Email

EAST LANSING, Mich. – A first-of-its-kind study from researchers at Michigan State University reveals that individuals who experience the most distress and impairment in daily functioning from social media use are more likely to believe fake news.  

“Social media are everywhere in our daily lives, and some people display problematic, excessive use of these platforms. We found that this overuse is associated with a greater tendency to believe in and engage with misinformation,” said Dar Meshi, an associate professor and co-author of the study, which published today in the journal PLOS One and was funded by MSU’s Trifecta Initiative. 

Meshi and his co-author, Maria D. Molina, both faculty members in the MSU College of Communication Arts and Sciences, conducted an online experiment in which 189 participants, age 18 to 26, were presented with 20 news stories formatted as social media posts. Ten of the stories were real and ten were false, and the order of delivery was randomized. By assessing participants’ credibility judgment of these news posts; participants intentions to click, comment, like and share posts; and their degree of problematic social media use, Meshi and Molina found that the greater people’s symptoms of problematic social media use, the more likely they were to: 

• believe fake news is true; 
• interact with news posts regardless if they were real or fake; and 
• want to click on fake news posts. 

Fake or false news falls under two categories: misinformation if it is unintentionally distributed and disinformation if it is intentionally distributed to deceive people.  

“False news has become a hotly debated and researched topic because of its availability to be shared and spread over social media. Over 60% of people in the U.S. read content on social media, and research has demonstrated that false news disseminates over social media at a greater rate than real news,” said Molina.  

The researchers believe their study is the first to look at how problematic social media use is involved with people’s trust in fake news by measuring their intended actions, like clicking, liking and sharing posts. Although the American Psychiatric Association doesn’t recognize problematic social media use as a clinical disorder, Meshi points out that it shares similarities with substance use and other behavioral addictive disorders. 

“People who display problematic social media use may feel bad if they can’t access it, and they might even return to it after trying to quit. This kind of behavior has been linked to job loss, poor grades and mental health issues,” Meshi said.  

Meshi and Molina hope their findings will help mental health professionals working with people who struggle with social media use, as well as others in the health care field. 

“Individuals with signs of problematic social media use may also be more susceptible to health-related misinformation, so clinicians specializing in different fields may benefit from awareness of their patients’ degree of social media use,” said Molina. 

The study’s findings could also help inform efforts from governmental agencies, organizations and social media companies to combat misinformation and disinformation.  

“By identifying people who are more likely to believe fake news, we can help reduce its spread,” Meshi said. “Researchers could work with social media companies to find ways to help these users and limit their exposure to fake news.” 

### 

Michigan State University has been advancing the common good with uncommon will for 170 years. One of the world’s leading public research universities, MSU pushes the boundaries of discovery to make a better, safer, healthier world for all while providing life-changing opportunities to a diverse and inclusive academic community through more than 400 programs of study in 17 degree-granting colleges. 

For MSU news on the web, go to MSUToday or x.com/MSUnews. 

---

Journal

PLOS One

DOI

10.1371/journal.pone.0321361 

Subject of Research

People

Article Title

Problematic social media use is associated with believing in and engaging with fake news

Article Publication Date

7-May-2025