Psychosocial predictors and outcomes of loneliness trajectories from childhood to early adolescence ☆

Two studies found that loneliness in childhood at age 5 years was not associated with depression several years later.

“Two studies found that loneliness in childhood at age 5 years was not associated with depression several years later,73 , 74”

Suicidal ideation during adolescence was not associated with prior loneliness during childhood.

“and suicidal ideation during adolescence, which was not associated with prior loneliness during childhood.74”

Two papers that measured both suicidal ideation and behaviour were excluded from the moderation analysis to avoid over-representation.

“Two papers (Salzinger et al.,2007; Schinka et al.,2013) measured both suicidal ideation and behaviour as outcome variables. To avoid over-representation, these papers were excluded from the moderation analysis”

Existing research has mostly examined the predictive role of adolescents' psychological or sociodemographic characteristics for loneliness trajectories.

“Existing research has mostly examined the predictive role of adolescents’ psychological or sociodemographic characteristics [9–13].”

The consistently high loneliness trajectory has been associated with various adverse health consequences in prior studies.

“In those studies, the consistently high loneliness trajectory was associated with various adverse health consequences [9, 10, 12, 13], indicating the importance of identifying predictors of chronic loneliness across adolescence.”

In this study, the proportion of adolescents experiencing chronic loneliness (0.8%) was smaller than that reported in previous studies (ranging from 3 to 22%).

“In our study, the proportion of adolescents experiencing chronic loneliness (0.8%) was smaller than that reported in previous studies (ranging from 3 to 22%) [9, 11–13].”

Studies on the longitudinal patterns of adolescent loneliness have identified several distinct trajectories, including consistently low and consistently high.

“Studies on the longitudinal patterns of adolescent loneliness have identified several distinct trajectories, including consistently low and consistently high [9–13].”

Despite differences in proportion rates, the patterns identified based on a single-item measure of loneliness reflected existing evidence from Western Europe and North America, where multi-item indicators of loneliness were used.

“Despite the differences in the proportion rate of each trajectory, the patterns identified based on a single-item measure of loneliness reflected existing evidence from Western Europe and North America, where multi-item indicators of loneliness were used [9, 11–13].”

The four trajectory patterns identified in this study echoed previous studies, where four to five distinct adolescent loneliness trajectories were observed.

“The four trajectory patterns identified in our study echoed previous studies, where four to five distinct adolescent loneliness trajectories were observed [9, 11–13].”

Children with a high level of loneliness are more likely to be depressed, aggressive, and have suicidal ideation.

“Children with a high level of loneliness are more likely to be depressed, aggressive, and have suicidal ideation.”

Increasing level of loneliness at 7 years of age, compared to low level, represents a greater chance of depressive symptoms (OR 1.32; p=0.004).

“the increasing level, when compared to the low level, of loneliness (Table 2) at 7 years of age represents a greater chance of depressive symptoms (odds ratio [OR] 1.32; p=0.004)”

At 15 years of age, the probability of depressive symptoms for increasing versus low loneliness is even greater (OR 2.05; p<0.001).

“while in adolescence, at 15 years of age, this probability becomes even greater (OR 2.05; p<0.001).”

Social isolation is associated with suicidal ideation at age 15, with OR 10.90 (p=0.001) for low versus growing loneliness and OR 18.89 (p=0.009) for low versus chronic loneliness.

“The authors also collected statistical data on the association between social isolation and suicidal ideation, in the assessment made at age 15, and concluded that this relationship proved to be very strong on two occasions: in the comparison between the low level and the growing level of loneliness (OR 10.90; p=0.001), and between the low and the chronic level of loneliness (OR 18.89; p=0.009).”