90% of dementia undetected in China

World Health Matters by Gary Finnegan – China – An international team of scientists has found that over 90% of dementia cases in China go undetected, with the highest level of undiagnosed cases in rural areas.

The public health experts behind the study, led by Dr Ruoling Chen at King’s College London, argue that more mental health education targeting high-risk populations is now needed to improve diagnosis rates, and increase support for sufferers and their families.

The level of undetected dementia reported in the new study is much higher than has been seen in studies undertaken in high-income countries, where about 60% of older adults with dementia are not diagnosed.

Published in the British Journal of Psychiatry and funded by Alzheimer’s Research UK and the BUPA Foundation, the large population-based study is a collaboration between scientists at King’s College London and other universities in the UK, and Anhui Medical University and five other medical universities in China.

The study is the first to examine factors influencing the poor diagnosis of dementia in older people in low-income countries, where there are more dementia sufferers than in high-income countries.

The team interviewed a random sample of 7,072 older adults in six provinces across China, with one rural and one urban community in each province. They identified 359 older adults with dementia and 328 with depression. There were only 26 participants who had doctor-diagnosed dementia reported and 26 who had doctor-diagnosed depression. Overall, 93% of dementia cases and 93% of depression was not detected.

It was found that, in China, undetected dementia among older adults is strongly associated with low socioeconomic status such as a low educational and occupational class, and living in a rural area.

Unlike in high-income countries, most of older Chinese people live with their families. A surprising, important finding was that undetected dementia is related to strong social support. Such ‘help available when needed’ may mask the disease and hinder detection, according to the authors. In addition, Chinese may interpret dementia symptoms in older people as being an acceptable part of the ageing process rather than as an illness.

“Dementia is increasingly a major global health challenge given that the world’s population is ageing. China has the most dementia sufferers of any country in the world, but at the same time it is a poorly recognised condition,” Dr Chen said.