Peking University, May 18, 2026 : In a recent study from Peking University Health Science Center, doctoral student Kang Ning and colleagues found that air pollution reductions alone cannot offset the impact of rapid population ageing on dementia deaths in China. The study has been published in The Lancet Healthy Longevity .
Why it matters
The research, titled "Trends of PM2.5‑attributable dementia deaths in the context of population ageing in China, 2000–60: a health impact assessment," analyzed historical data (2000‑2024) and projected trends to 2060 under five policy scenarios.
Although China's clean air policies have substantially lowered PM2.5 exposure over the past decade, the study found that dementia-related deaths linked to air pollution have continued to rise.
Temporal trend of key inputs for estimating PM2.5-attributable dementia deaths in China.
Key findings
Researchers identified population ageing as the main reason for this trend. While lower PM2.5 levels have brought clear health benefits, the rapid growth of China's older population has increased the number of people vulnerable to dementia, offsetting much of the progress made through cleaner air. Future projections indicate that sustained air quality improvement is essential, but halting the upward trend requires coordination of clean air policies with carbon neutrality efforts.
A related commentary in The Lancet Healthy Longevity by Bin Jalaludin and Zeng Xiaowen notes that the PM2.5‑dementia risk relationship is non‑linear, and that health benefits of reducing PM2.5 may be limited when "most of the reductions in PM2.5 concentrations occur within the high-concentration plateau, where risk reductions are marginal." The authors also emphasize the need for wider public health measures, including healthy ageing, dementia prevention, early screening, and chronic disease treatment.
Future implications
The study suggests that, ultimately, stronger action on pollution and carbon emissions, combined with ageing-focused health strategies, will be needed to protect public health in the decades ahead.
*This article is featured in PKU News "Why It Matters" series. More from this series.
Read more: https://www.thelancet.com/journals/lanhl/article/PIIS2666-7568(26)00025-5/fulltext
Written by : Jenny Chock
Edited by : Chris Tang Xiao Tong, Chen Shizhuo
Source : PKU News ( Chinese )
The Lancet
Trends of PM2·5-attributable dementia deaths in the context of population ageing in China, 2000–60: a health impact assessment
5-May-2026