More than one-fourth of the older population in rural China affected by mild cognitive impairment

Mild cognitive impairment (MCI) is considered the preclinical stage in progressive cognitive decline leading to the clinical stage of dementia. A study published in the journal Alzheimer's & Dementia reports that over one-fourth of rural-dwelling older adults in China are affected by MCI.

The MIND-China project recruited participants aged 60 years or older and living in rural communities in Yanggu county, western Shandong Province. In 2018, a total of 5,068 participants were examined, and 1342 of these were defined to have Mild Cognitive Impairment (MCI) according to international criteria that integrated standard neuropsychological tests and clinical judgment, leading to an overall prevalence of 26.5%.

Amnestic MCI accounted for over four-fifths of all persons with MCI. In addition, older age, low education, and being a farmer were factors associated with MCI and amnestic MCI, whereas hypertension and a history of stroke were associated with non-amnestic MCI, a type of MCI that affects cognitive abilities other than memory, such as language, speed, and executive function.

"This study targeted older residents who were living in rural communities. We diagnosed MCI and its main subtypes by integrating psychological tests with clinical assessments," says Chengxuan Qiu, a senior researcher at the Department of Neurobiology, Care Sciences and Society, Karolinska Institutet.

"It is relevant to help understand epidemiology of MCI in the rural population in China," he adds.

High prevalence of MCI

The results in the study revealed a relatively high prevalence of MCI, especially amnestic MCI, in this rural population. This may be partly due to the facts that local residents have relatively low socioeconomic positions and low education, and that major cardiovascular risk factors and related disorders are highly prevalent in this rural area.

"MIND-China is an ongoing intervention study of dementia and disability. Thus, we will be able to evaluate whether multidomain interventions may help people with MCI to maintain or improve their cognitive function and to delay dementia," says Yifeng Du, a professor and senior neurologist at Shandong Provincial Hospital.