Researchers in China have launched a major study following over 1,000 people to understand how Alzheimer’s disease develops and changes over time. The study, called BCAS, collects information about people’s thinking abilities, brain scans, and blood tests to track who might develop memory problems. Early results show that certain brain markers—especially tau protein—are more closely linked to thinking difficulties than amyloid protein. The study also found that factors like age, education, and diabetes affect how well people’s brains work. This research could help doctors catch Alzheimer’s earlier and create better treatments tailored to individual patients.

The Quick Take

  • What they studied: How Alzheimer’s disease develops in people’s brains by tracking their thinking abilities, brain scans, and biological markers over time
  • Who participated: 1,013 people aged 40 and older in China who came to a memory clinic because they had concerns about their thinking or memory. The average age was 66.5 years, about half were women, and most had some high school or college education
  • Key finding: A brain protein called tau appears to be more strongly connected to thinking problems than another protein called amyloid. People with tau in their brains scored about 0.97 points lower on thinking tests, while those with amyloid scored about 0.53 points lower
  • What it means for you: This research suggests doctors may need to pay more attention to tau protein when checking for Alzheimer’s disease. However, this is early research from one study, so more work is needed before changing how doctors diagnose or treat the disease

The Research Details

The BCAS study is a long-term tracking study that started in 2016 at a major hospital in China. Researchers recruited people who were worried about their memory or thinking and gave them thorough check-ups including thinking tests, brain scans, and blood work. The study uses two types of special brain scans (called PET scans) that can see amyloid and tau proteins in the brain—the proteins thought to cause Alzheimer’s disease.

Participants come back every 1-2 years for repeat testing so researchers can watch how their brains change over time. This approach is valuable because it follows real people in a real clinic setting, not just in a laboratory. The study is still ongoing, and this report describes the first 1,013 people who joined by January 2025.

The researchers collected detailed information about each person’s health history, lifestyle habits, education level, and any medical conditions like high blood pressure or diabetes. This comprehensive approach helps researchers understand all the different factors that might affect Alzheimer’s risk.

This type of long-term tracking study is important because Alzheimer’s disease develops slowly over many years. By following the same people repeatedly, researchers can see exactly how and when changes happen in the brain. This is much better than just comparing different groups of people at one point in time. The study is also valuable because it focuses on Chinese people, and most Alzheimer’s research has been done in Western countries where the disease might develop differently.

This study has several strengths: it uses standardized, well-established tests for thinking abilities; it includes advanced brain imaging that can actually see the proteins causing Alzheimer’s; it collects blood samples for biological markers; and it follows people over time rather than just looking at them once. The study is based at a major university hospital, which suggests good quality control. However, because this report only covers baseline (starting) information, we don’t yet have long-term follow-up data showing how people changed over time. The participants are also from one region of China, so results might not apply to other populations.

What the Results Show

The study confirmed what researchers expected: people with normal thinking abilities scored highest on memory tests (average score 19.2 out of 30), people with mild cognitive impairment scored lower, and people with dementia scored the lowest. This pattern shows the tests are working correctly.

The most important new finding was about tau protein. People who had tau in their brains (detected by PET scans) scored noticeably lower on thinking tests compared to people without tau. The difference was larger than for amyloid protein, suggesting tau might be more directly connected to thinking problems. This is important because it could change how doctors look for Alzheimer’s disease.

The study also identified several factors linked to better or worse thinking abilities. People with more education performed better on thinking tests, and people who drank tea regularly also did better. Surprisingly, people with slightly higher body weight (BMI) also showed better thinking scores, though researchers note this finding needs more investigation. On the negative side, older age and having diabetes were linked to lower thinking scores.

The study found that high blood pressure, diabetes, and high cholesterol were common among participants (41%, 15%, and 12% respectively), showing these are important health issues in this population. The researchers also noted that the study successfully collected brain scans and blood samples from many participants, creating a valuable resource for future research. The data quality appears good, with consistent patterns matching what scientists expect from Alzheimer’s disease progression.

These findings fit with previous research showing that tau protein may be more closely tied to thinking problems than amyloid protein. However, most previous studies were done in Western countries, so this Chinese study helps confirm whether these patterns hold true in different populations. The finding about education protecting thinking abilities matches many previous studies. The unexpected finding about higher BMI and better thinking scores is interesting and different from some previous research, suggesting this relationship might be complex or specific to this population.

This report only describes the starting point of the study, not the long-term follow-up results, so we can’t yet see how people actually changed over time. The participants are from one region of China and came to a memory clinic, so they might not represent all Chinese people or all people with thinking problems. The study hasn’t yet published detailed results about how the different biological markers predict who will develop dementia in the future. Additionally, we don’t know how long people will be followed or how many will complete the full study.

The Bottom Line

Based on this early research, there is moderate evidence that doctors should pay attention to tau protein when evaluating people for Alzheimer’s disease, possibly even more than amyloid protein. However, these are preliminary findings from one study, so major changes to medical practice aren’t recommended yet. People concerned about memory problems should continue to see their doctors for evaluation using current standard tests. Maintaining education, staying mentally active, managing diabetes, and controlling blood pressure remain important for brain health based on this and previous research.

This research is most relevant to people over 40 who are concerned about memory or thinking problems, their family members, and doctors who evaluate memory problems. It’s also important for researchers studying Alzheimer’s disease and pharmaceutical companies developing new treatments. People without memory concerns don’t need to change their behavior based on this single study. This research is particularly relevant to people of Chinese descent, though the findings may apply more broadly.

This is a long-term study, so meaningful results about how people change over time won’t be available for several more years. Researchers typically need to follow people for at least 2-5 years to see significant changes in thinking abilities and brain markers. The study is ongoing, so new findings should be published periodically as more follow-up data is collected.

Want to Apply This Research?

  • Users concerned about memory could track their performance on simple thinking games or memory tests monthly, noting any changes. They could also track modifiable risk factors like tea consumption, education/learning activities, diabetes management, and blood pressure readings to see if these correlate with their cognitive performance over time.
  • Based on this research, users could increase tea consumption, engage in regular learning activities (reading, puzzles, classes), maintain healthy blood pressure and blood sugar levels through diet and exercise, and stay socially and mentally active. The app could send reminders for these activities and track consistency.
  • Set up quarterly check-ins where users complete the same thinking test or memory assessment and compare results over time. Track lifestyle factors (tea drinking, learning activities, exercise, blood sugar/blood pressure if available) alongside cognitive performance to identify personal patterns. Share results with healthcare providers during annual check-ups.

This research describes an ongoing study and reports only baseline (starting) findings, not long-term outcomes. The findings are preliminary and come from one study in China, so they should not be used to change medical treatment without consulting a healthcare provider. If you or a loved one are concerned about memory or thinking problems, please see a doctor for proper evaluation and diagnosis. This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.