In East Asian cultures, it is a traditional family model for older adults to live with their children. Living arrangementsare considered as a form of filial piety in Confucianism [1]. However, this tradition has been challenged in China. According to the tenets of modernization theory, as societies become more modernized, there will be a corresponding decrease in household size and an increase in elderly individuals living separately from their children [2]. According to the 1982–2020 population censuses in China, household sizes shrank, and intergenerational family structure is growing simpler. Even the universal implementation of the two-child policy in China failed to change these trends. In 1982, the average household size was 4.41 persons, and the size decreased to 2.62 in 2020. In 1982, families with only one generation accounted for 13.9% of all families; the percentage increased to 49.5% in 2020. In 1982, although families with two generations accounted for 48.2% of all families, the percentage declined to 36.7% in 2020 [3]. Indeed, it is increasingly more common for Chinese seniors to live only with their spouses or by themselves. Currently, living alone has become one of the two major living arrangements for China’s older people, with the other being intergenerational coresidence.
From a global perspective, older people’s living arrangements have been identified as a significant component of healthy aging [4]. The growing popularity of solitary living among older people in China has somewhat jeopardized the traditional “intergenerational feedback model” in Confucianism. It weakens the emotional connections between parents and children from a spatial perspective and has raised concerns about the mental health of older adults who live alone. Compared to young people, seniors are more vulnerable. They are more susceptible to mental diseases caused by external influences [5]. As China is going through compressed modernization and a compressed aging process, the conflicts between tradition and modernity are partially reflected in older adults’ living arrangements. The traditional culture, which highlights filial piety and takes the form of intergenerational coresidence, and the modern family model, which emphasizes independence, have firm advocates. Consequently, many studies have associated living arrangements, a reflection of China’s social changes, with seniors’ mental health. Nevertheless, there remains controversy over the conclusions of quantitative analysis [6, 7].
The significant causeof the disagreement is the complicacy of the relationship between living arrangements and seniors’ mental health, as living with adult children has benefits and disadvantages for seniors [8]. Family-support theories maintain that living with adult children helps seniors obtaineconomic, emotional, and other support. It fosters harmonious family relationships [9]. Living arrangements are vital environmental elements and resources that enable older people to make requests from their cohabitants, which significantly influences their lifestyles, cognitive functions, and mental health. In the long-maintained tradition in China that prioritizes filial piety, living with adult children is considered as the most ideal living arrangements for seniors [10]. Rixiang et al. [11] utilized the Chinese Longitudinal Healthy Longevity Study for research and found that seniors living alone were 1.26 times more likely to experience depression than those who lived with family members. Similar findings were observed in studies ofKorean [12, 13], Vietnamese [14], and Japanese [15]. The familism upheld by East Asian cultures, which refers to the “perceived power of family connects and a sense of loyalty to family” [16], strongly influences seniors’ living arrangements and their children’s responsibilities to take care of them.
Family conflict theories claim that parents find it difficult to relate well to adult children with whom they live. Diverse life habits and values of intergeneration may cause conflicts in family life. Such contradictions may weaken the benefits of intergenerational support and impair parents’ welfare [17]. One reason for family conflicts arising from intergenerational coresidence is the generation gap. China’s opening-up has brought dramatic societal changes, which contribute to distinct social backgrounds between generations. Accordingly, generation gap has become a vital feature of intergenerational relationships. Differences, estrangements, and conflicts are identified betweengenerations in terms of social-value orientation and behavior models [18]. For example, due to the considerable differences between China’s young parents and seniors in terms of childcare, children’s education easily becomes the trigger of conflicts in families in which seniors live with their children [19, 20]. Moreover, additional family members complicate family relationships in various ways, as subtle competition for family status, authority, and even intimate relationships arises between generations. For example, in Chinese families of intergenerational coresidence, the relationship between a mother-in-law and her daughter-in-law is a major trigger of family conflicts [21]. Research showed that family conflicts were detrimental to the mental health of older people who lived with their children [22]. Ren and Treiman[23] examined the data from the 2010 China Family Panel Studies (CFPS) and found that seniors who lived with their adult children were less happy and more depressed than those who lived with spouses.
The association between solitary living and seniors’ mental health remains unclear in China. The fundamental reason is that intergenerational relationships in Chinese families present a “duality” where traditional cultural resilience and the tensions caused by divergent intergenerational values exist. Intergenerational responsibility and ethics carry a binding force over individual behavior in family life, laying the basis for the traditional “intergenerational feedback model”. However, as older people and their adult children hold different values, these divergences become the root cause of intergenerational family conflicts [24]. Meanwhile, unresolved endogeneity issues add more uncertainty to research conclusions. Seniors’ mental health can be interpreted as a result of living arrangements [6]. This “duality” may have confused the observed relationship between living arrangements and seniors’ mental health. Thus, the marginal contribution of this research lies in our utilization of an instrumental variable (IV) to address endogeneity and panel-data analysis to reduce biased results caused by unobserved factors. Based on the research methodology employed, we adopted an unconventional classification for solitary living, distinguishing between “living close to adult children” and “living far from adult children,” as opposed to the conventional binary division of “solitary living” versus “cohabitation with adult children”. Living close to adult children is viewed as a strategic measure for reconciling the desire for personal independence with the demand of nurturing intimate relationships. Compared with the binary division, this trichotomy reflects a strategic and adaptive choice that families make to tackle the “duality” of intergenerational relationships. It portrays seniors’ living arrangements more accurately, paving the way for a precise analysis of the relationship between solitary living and the mental health of seniors in China.