Trends in cognitive impairment among older adults in China from 2002 to 2022: Evaluating the impact of the COVID-19 pandemic.

Cognitive impairment is a growing public health concern, particularly in aging populations. While trends in CI prevalence in China were studied up to 2018, no previous research has explored how the COVID-19 pandemic has affected these trends. This study aims to extend the analysis to 2022, examining the impact of the pandemic on cognitive impairment prevalence. The Chinese Longitudinal Healthy Longevity Survey (CLHLS) data across multiple waves (2002 to 2022) was used (n=64,872). Cognitive impairment was assessed using a Chinese version of the Mini-Mental State Examination (MMSE). The rural/urban-sex-single age-specific prevalence of cognitive impairment across different waves were estimated using the DemoRates R package. Cognitive impairment trends before and after the onset of the COVID-19 pandemic were compared to identify any significant changes. In 2018 and previous waves, an average of 16,191 participants per wave were surveyed (four waves), with a cognitive impairment prevalence of 4.3%. In 2022, post-COVID-19, the survey included 14,022 participants and showed a significant increase in CI prevalence to 6.8%. The observed trends were independent of gender, age group, and residential environment (P-trend < 0.001). However, a significant decrease in mean calf circumference, increase in proportion of overweight participants, and increases in daily fruit and vegetable intake and regular physical activity were notable after the pandemic. The study suggests that the COVID-19 pandemic may have contributed to the observed increase in cognitive impairment prevalence in China, underscoring the importance of further research into the long-term cognitive effects of global health crises. These findings highlight the need to strengthen healthcare systems to support cognitive health in an aging population, while considering both pandemic-related and ongoing factors in the management of cognitive impairment.