UBC researchers to help identify Alzheimer’s risks specific to people of Asian ancestry

Researchers at the University of British Columbia are helping lead a first-of-its-kind project to improve Alzheimer's disease prevention, diagnosis and care for people of Asian ancestry across North America.

UBC Hospital in Vancouver is one of 16 medical centres across the continent taking part in the Asian Cohort for Alzheimer's Disease (ACAD), which will study the disease in people of Chinese, Korean and Vietnamese ancestry before expanding to other major Asian populations.

Alzheimer's is the most common type of dementia, affecting around seven per cent of people over 65 in Canada in 2013 and 2014, according to Statistics Canada.

It causes progressive memory loss and cognitive decline, affecting mood, judgment and reasoning, and the ability to speak and communicate.

The Alzheimer's Society of Canada estimates nearly 600,000 people were living with dementia in 2020, a figure that is estimated to grow to 912,000 by 2030.

But people of Asian ancestry are vastly underrepresented in Alzheimer's research, according to ACAD and the U.S.-based Alzheimer's Association — comprising between 0.5 and three per cent of participants in major clinical trials and national data sets used to set prevention, diagnosis and treatment guidelines.

By contrast, 16.4 per cent of people in Canada identify as either Chinese, Japanese, Korean, Filipino, south Asian or southeast Asian, according to the most recent census — and that figure increases to 28.2 per cent in British Columbia.

This gap means health-care providers don't have key information about Alzheimer's risks and presentations for people of Asian ancestry that could help them diagnose and treat it earlier, said Dr. Robin Hsiung, an associate professor of neurology at UBC who is heading up the Vancouver ACAD site.

"Most of the research that is done in North America and Europe is based on people of Caucasian descent, and it is now recognized that a lot of diseases actually have very different presentation and different risk factors," said Hsiung, who is also a researcher at the Djavad Mowfaghian Centre for Brain Health.

For example, a 2021 study suggests that while African American people are about twice as likely to develop Alzheimer's as white people, some of their risk is likely linked to genetic features not identified in previous research that focused on white people.

Also, a small 2022 study in the Journal of Human Genetics suggests certain genetic features are less frequent among Asian people but are associated with higher risks, said Hsiung.

"Unless we collect the data and do some of this analysis on a specific population, then we don't really know," he said.

ACAD researchers are investigating how genetic and environmental risk factors for Alzheimer's, like diet and exercise, might differ from white people of European ancestry in North America and also Asian people living in Asia.

They also hope to identify genetic biomarkers specific to Asian people and create an Alzheimer's risk score model to help health-care providers more accurately assess and treat the disease in Asian Americans and Asian Canadians.

Language barriers and tests not designed with Asian-specific risk factors in mind make it difficult to catch the disease early, when medication and treatment have the best chance of slowing its progression, Hsiung said.

"By using that data that we collected, we can look at any disparity that we observe in this population and how we might help to mitigate that and minimize the disease's impact on their health," said Hsiung.

Stigma, knowledge key barriers: advocates

Sharon Tong at the Alzheimer's Society of B.C. says culturally specific knowledge and care is incredibly important for Chinese people with Alzheimer's and their families.

She and Joann Wong Bittle, chair of the society's Chinese Advisory Committee, say stigma about Alzheimer's can be significant in Chinese communities.

"There are a lot of myths about the disease that really are creating a lot of barriers for families to seek help," said Tong. "They feel very shameful if they share [the diagnosis] with the social circles. So, they try to keep everything at home."

Many might not know about specific symptoms or might dismiss memory loss as a natural part of aging, added Wong Bittle.

The society began its Chinese services more than 20 years ago, and they now include Mandarin and Cantonese support lines for caregivers, support groups, and group exercise and social activities for people and their families.

Wong Bittle hopes the findings of the ACAD study will help educate individuals and families about what to look for and where to ask for support.

"I think bringing awareness and having that knowledge will really help to bridge that gap," she said.

ACAD is being funded by a $40.6 million US grant from the U.S.-based National Institute on Aging, which is part of the National Institutes of Health.

Hsiung says he and his team in Vancouver will be recruiting people of Asian ancestry over 60, with and without cognitive impairments, to participate in the study.