Maintaining the cognitive health of older adults is a focal point in alleviating the pressures of aging, achieving healthy aging, and enhancing the quality of life in later years. According to the data from the “World Population Prospects 2022” report, the proportion of the population aged 65 and above was 10% in 2022 and is projected to rise to 16% by 2050 [1], indicating a further deepening of global population aging. China is no exception to this trend. As of the end of 2022, the population aged 65 and above in China reached 209.78 million, accounting for 14.9% of the total population [2], and it is projected to increase to 29% by 2050 (Du & Li, 2021) [3], surpassing the global rate of population aging. Focusing on older adults and improving their well-being is key to achieving active aging. However, cognitive decline poses a potential threat to the quality of life in old age. From 2000 to 2020, the prevalence of cognitive impairment in older adults in China was 22.0% (Wang et al., 2020) [4]. From 2018 to 2021, Subjective Cognitive Decline (SCD) affected 58.33% of older adults in China (Cheng et al., 2023) [5]. Cognitive function has a low reversibility, making treatment and rehabilitation difficult, and the cost of medical services and long-term care is high. This not only imposes a heavy burden on individuals, families, and society (Ritchie et al., 2016) [6], but may also reduce the life expectancy and increase the risk of mortality for the older adults (Yaffe et al., 2016) [7].
As early as 2002, the World Health Organization (WHO) proposed the concept of active aging and emphasized that the social participation of older people is a core element in promoting an actively aging society (Kalache et al., 2003) [8]. In 2022, China also emphasized the importance of advancing the Healthy China initiative and implementing a proactive strategy to address population aging. Ensuring the social participation of older people is a key aspect in addressing the issue of population aging. Previous studies have found that social participation among older people contributes to their physical and mental health (Barbieri, 2021; Zhang et al., 2022) [9, 10], but further verification is needed regarding its impact on cognitive function.
Many scholars define social participation as the process in which older adults actively participate in various activities such as social, cultural, entertainment, and volunteer services based on legal channels and their own needs, and establish connections and interactions with the community, family, friends, and others (Alma et al., 2012; Van Hees et al., 2020) [11, 12]. Based on previous research, this study defines older adults’ social participation as their involvement in activities that are beneficial to themselves or social development. These activities span various aspects, including interpersonal communication, leisure and entertainment, and household labor (Goll et al., 2018) [13].
The relationship between social participation and cognitive function needs to be clarified, and there are differences in opinions among different scholars. Some scholars have pointed out that social participation has a positive impact on the cognitive function of older adults (Park, et al., 2022; Wang et al., 2022) [14, 15]. Studies have found that older adults who participate in activities have better cognitive function compared to those who do not participate (Zhou et al., 2020) [16]. In old age, engaging in active social activities can not only alleviate the decline in perceptual speed (Lövdén et al., 2005) [17], but also mitigate cognitive aging (Nie et al., 2021) [18]. This is because, on the one hand, social participation increases interpersonal interaction in older adults, thereby stimulating the brain and hormone levels, and relieving cognitive problems (Shen et al., 2022) [19]. On the other hand, social participation enhances a sense of belonging and achievement in older adults, thereby preventing cognitive decline (Berkman, 2000) [20]. Some specific research has found that participating in social and leisure activities can alleviate the decline in cognitive abilities in older adults (Litwin & Stoeckel, 2016) [21]. Internet use has been shown to have beneficial effects on cognitive function in later life (Berner et al., 2019; Kamin & Lang, 2020) [22, 23], and social and intellectual activity participation are of relative importance to predict cognition in old age (Fernández et al., 2023) [24]. However, some scholars believe that there is a negative relationship between social participation and cognitive function in older adults. In terms of the types of participation, some scholars have pointed out that unhealthy behaviors such as smoking and drinking may impair the cognitive function of older adults (Mercken et al., 2010) [25]. In terms of the level of participation, high-frequency social participation may have a negative impact on the cognitive function of older adults. For example, frequent participation in high-stress activities may not be beneficial for maintaining the cognitive function of older adults (Kawachi & Berkman, 2001) [26]. In terms of the places of participation, participating in places such as bars and funerals may have adverse effects on the cognitive function of older adults (Watkins, 2004) [27]. In addition, negative social interactions and unhealthy social interaction patterns are also detrimental to maintaining the cognitive function of older adults (Myroniuk & Anglewicz, 2015) [28]. In addition, some scholars believe that there is no significant relationship between social participation and cognitive function in older adults. A study conducted on older adults in Amsterdam, Netherlands found no significant association between social participation and cognitive function (Aartsen et al., 2002) [29]. McGue and Christensen (2007) also found that social participation had no significant effect on improving cognitive function in older adults [30]. Research has also found that social activity participation does not have an impact on cognitive decline in older men (Hwang et al., 2018) [31].
In summary, although there have been some achievements in the research on the relationship between social participation and cognitive function in older adults, there is still no consensus and further exploration is needed. Firstly, most studies have only assessed the association between social participation and cognitive function at a single time point or in the short term, with very few studies examining the long-term impact of social participation on cognitive function and tracking individuals over several years. Secondly, Previous measures of social participation have primarily focused on the interaction with others, whereas this study comprehensively examines the impact of social participation by including not only group interaction-type social participation but also self-recreational and household labor-type social participation. Finally, in the research process, existing studies have focused more on the direct impact of social participation on cognitive function in older adults, with less exploration of the intermediate mechanisms through which social participation affects cognitive function. Therefore, this study will further analyze the impact of social participation on cognitive function in older adults, providing evidence from China for international research on aging.