What doesn't kill you makes you "smarter": The long-term association between exposure to epidemic and cognition

Emerging epidemics have devastating impacts on people's lives and livelihoods. However, acting as a severe health shock, exposure to an epidemic may induce positive changes in health behaviors among survivors, thereby leading to long-lasting improvement in population health. This study examined the long-term association between exposure to the 2002-2004 severe acute respiratory syndrome outbreak and middle-aged and older Chinese adults' cognition assessed in 2011-2015. Drawing on data from the 2011-2015 China Health and Retirement Longitudinal Study, we found that community exposure to the outbreak was associated with significantly higher scores on episodic memory, after adjusting for demographic characteristics, adulthood socioeconomic status and health, and community socioeconomic conditions. No such a significant association was found for mental intactness. Mediation analysis showed that community exposure to the epidemic was associated with increased participation in social activities, maintaining close family relationships with adult children and grandchildren, and increased participation in regular physical exercise, all of which were positively associated with cognitive functioning in middle-aged and older Chinese adults. These findings suggest that positive post-epidemic behavioral changes are possible and may have long-term health benefits for survivors.