Testing Reciprocal Relationships between Loneliness and Self-Control among Middle-aged and Older Adults: A Random Intercept Cross-lagged Panel Model Using Daily Diary Data

Abstract

Purpose Loneliness is one of the most critical causes of ill-being among the elderly (Chen & Feeley, 2014). Empirical evidence has revealed that loneliness in later adulthood causes various physical and mental problems such as depression, cardiovascular health (Courtin & Knapp, 2017), suicidal ideation (Beutel et al., 2017), and dementia (Holwerda et al., 2014). The importance of feeling connected in later adulthood is best summarized by the director of the Harvard Study of Adult Development (Waldinger, 2016), who said that “Loneliness kills. It’s as powerful as smoking or alcoholism.” Among several factors that may account for loneliness, one critical factor that has been understudied and may help better understand the development of loneliness is the potential role of self-control (Stavrova et al., 2021). In the present study, we examined the relationship between loneliness and self-control among middle-aged and older adults. In addition, we seek to investigate whether and how the daily fluctuation in self-control skills and loneliness within an individual affect each other. Method An online diary study over 8 consecutive days was conducted among 694 middle-aged and older adults. Employing a random intercept cross-lagged panel model (RI-CLPM) in Mplus 8.0, we separated dynamic within-individual processes (measured as lagged effects between daily changes in loneliness and self-control) from more stable individual differences in the variables (measured as the covariance between random intercepts) (Hamaker et al., 2015; Mulder & Hamaker, 2020; Usami, 2021), which allow us to see inter-and intra-individual relationships between loneliness and self-control. Results and Discussion There was a negative relationship between loneliness and self-control skills at the between-person level, indicating that those with higher loneliness tend to have poor self-control skills than people who feel loneliness less or vice versa. More importantly, by applying RI-CLPM to daily diary survey data, we elaborated the relationship at the within-person level. For a given individual, a higher than usual loneliness on a given day is followed by a decrease in self-control on the next day. In turn, the decreased self-control skill exacerbated the feeling of loneliness on the following day. Significant differences were also found in the reciprocal relationship between loneliness and self-control by demographic characteristics (i.e., age, marital status). There were greater negative influences of self-control on loneliness for middle-aged and married individuals than their counterparts. Discussion highlights the importance of maintaining self-control ability on a daily basis to reduce loneliness in middle-aged and older adults, considering the several domains of self-regulation (i.e., emotional, cognitive, behavioral). In addition, the potential role of loneliness in the development of self-control skills was addressed.