Loneliness is a public health problem that has gained increasing attention and importance in politics and health research [1], especially since the COVID-19 pandemic [2]. During the pandemic, social relationships between children and adolescents were significantly reduced by protective measures [3]. In this context, the possible health consequences of social isolation have been frequently discussed [4]. For example, psychological and psychosomatic burdens have increased [5]. Furthermore, some studies imply that loneliness among children and adolescents also increased during the pandemic [3].
Loneliness is mostly defined as an aversive experience due to qualitatively or quantitatively deficient social relationships. Discrepancies between existing and desired relationships are subjectively perceived and painfully experienced [6, 7]. This means, on one hand, that people can be alone without feeling lonely and, on the other hand, that loneliness can also be experienced despite existing social contacts. Weiss [8] made a further central differentiation by distinguishing between social and emotional loneliness. Social loneliness refers to a deficit of social networks (e.g., in the peer group or the workplace). Emotional loneliness refers to a lack of intimate attachments (e.g., romantic partners and close friendships). Therefore, in the present study, we define loneliness as an aversive feeling due to a perceived lack of emotional or social relationships.
There are numerous studies on the prevalence and development of loneliness in adulthood [9, 10, 11, 12, 13]. However, there are only a few findings on the development of loneliness before and after the onset of the COVID-19 pandemic in children and adolescents. There is a lack of research on loneliness in this age group, especially in Germany.
Therefore, the present study aimed to determine the prevalence of loneliness before (2018) and after (2022) the onset of the COVID-19 pandemic and to investigate subgroup differences.
Loneliness in Children and Adolescents
Loneliness is prevalent across different stages of life [14], but adolescents are particularly vulnerable to this phenomenon due to physical, psychological, and social changes [15]. For example, the need for close friendships, mutual understanding, and belonging to a peer group grows between childhood and adolescence [16]. Adolescents gradually detach themselves from the parental home, and peers take the position of central attachment figures [17]. Previously satisfying relationships, such as those with the family, may no longer be perceived as sufficient as the need for peer group relationships and romantic partnerships grows [15]. Consequently, a perceived lack of romantic relationships [16], friendships, peer rejection [18], and lack of support from classmates [19] may be related to loneliness.
This relationship between social connections and loneliness illustrates the relevance of the COVID-19 pandemic and the associated protective measures for the development of loneliness in children and adolescents. The pandemic has significantly disrupted the social relationships of young people [3]. For example, studies have shown that 66.4% of children and adolescents felt less connected to their friends during the pandemic and 33.6% reported a general negative impact of the pandemic on their friendships [20]. Moreover, studies have reported a decrease in time spent with friends [21, 22], reduced satisfaction with friendships [21], and a lack of emotional connection and support [22]. The relevance of the COVID-19 pandemic for the experience of loneliness is also shown by the increase in psychological and psychosomatic complaints identified in the COPSY (Corona and Psyche) study [5]. In turn, physical and psychological complaints are closely linked to loneliness in young people [23, 24, 25].
The Prevalence of Loneliness Before the COVID-19 Pandemic
Loneliness among children and adolescents was already widespread before the coronavirus pandemic. The international HBSC Surveys examined loneliness in 11–15-year-olds with one item. Here, the adolescents could, for example, answer the question "Thinking about the last week, have you felt lonely?" [26] with different response options. Those who chose the top two options, e.g., "very often" and "always" were rated as lonely. The prevalence of loneliness was 8.2 % (England) [26], 6.3 % (Denmark) [27], and 15 % (Finland) [28], depending on the study. German studies assessed loneliness in people aged 16 and older with a single item [1] or aged 14 and older using the University of California, Los Angeles scale (UCLA scale) [29]. The prevalence of loneliness ranged from 23.4% [1] to 26% [29]. However, earlier phases of childhood and adolescence were not recorded here.
In terms of sociodemographic differences in the prevalence of loneliness, many studies have shown that loneliness tends to be more prevalent among girls [28, 30, 31]. Other studies found no gender-specific differences [32] or slightly greater levels of loneliness in boys [33]. Regarding the age group, numerous studies detected higher loneliness among older adolescents [26, 31], while other studies identified a higher prevalence in younger students [25, 34]. Furthermore, students with lower socioeconomic status have a higher prevalence of loneliness [26, 27, 31].
The prevalence of loneliness in children and adolescents increased before the pandemic [27, 28, 35]. For example, the cross-national PISA study investigated loneliness among 15- and 16-year-old students. Approximately twice as many young people worldwide reported higher levels of loneliness at school in 2018 than in 2012 [35].
The Prevalence of Loneliness in the Context of the COVID-19 Pandemic
The prevalence of loneliness among children and adolescents has gained attention in the context of the coronavirus pandemic both nationally [31, 36] and internationally [3,22].
For example, the international OxWell study used the UCLA-3 scale to analyze the increase in loneliness among children and young people during the lockdown. Here, 35% of respondents stated that they felt lonelier than before the pandemic. This is a retrospective survey, however, as loneliness was only recorded at one point in time [37]. A further international study that took this aspect into account and recorded loneliness before and during the COVID-19 pandemic also revealed an increase in loneliness between October 2019 and April 2020 [22]. In contrast, a study from China did not find any increase in loneliness among children in the context of the COVID-19 pandemic [38]. Thus, further international studies [39] and reviews [3] confirmed the increase in loneliness among children and adolescents during the pandemic.
In Germany, for example, the COPSY study investigated loneliness during the COVID-19 pandemic in 11- to 17-year-olds using one item. Here, 10% of the respondents said they were often lonely and 24% said only sometimes. However, there is no comparison with the time before the pandemic [40]. The German Pairfam study again takes this into account and compares loneliness before and during the pandemic. Loneliness was examined in children and adolescents aged 14-17 years using a single item of the UCLA scale. A significant increase in loneliness was found. A limitation of this study is that loneliness was recorded during the first period of the pandemic when many measures were still in place. Furthermore, loneliness was assessed with different formulations and within different periods, which makes comparisons less meaningful [41].
Changes in Loneliness in the Context of the COVID-19 Pandemic Depending on Sociodemographic Characteristics
Of these national and international studies showing that loneliness has increased during the pandemic, very few have analyzed how this increase has changed depending on sociodemographic factors such as age, gender, and family affluence. For example, studies have demonstrated that children and adolescents from families with a lower socioeconomic status experienced greater increases in mental health problems during the COVID-19 pandemic [42].
In terms of loneliness, it might be that due to school closures, children and adolescents lack social connections independent of their family affluence. Even with high financial resources, avoiding closures and reconnecting with peers in person may have been difficult. The studies found in the research [22, 41] did not analyze how the increase differs according to family wealth.
Regarding gender, Alt et al. [41] showed that the increase in loneliness during the pandemic did not differ between girls and boys. However, before the COVID-19 pandemic, a greater increase in loneliness among girls was shown [28, 35]. This finding is in line with studies indicating increased psychological burdens in girls compared with boys in the context of the pandemic [43, 44]. A possible explanation could be that girls are more vulnerable to psychological stress and worries about the pandemic [43, 45]. On the other hand, it might be that in terms of loneliness, there are no gender differences because the isolation due to the restriction measures caused a lack of social relationships, not only for one gender. It is not to be assumed that the desire to end loneliness and to reconnect with people is gender specific [16].
The extent to which the increase in loneliness during the pandemic differed according to age was not reported in the studies. The findings on the increase in mental health problems during the pandemic have been heterogeneous [5, 43, 44, 46]. Regarding loneliness, it is possible that loneliness increased in children and adolescents to a similar extent but due to different age-related needs. For example, adolescents are more likely to develop loneliness if their needs for peer contact and romantic relationships are not met, while quantitative contact with play partners has a greater role for younger children [16]. Both aspects have been restricted during the pandemic and therefore represent potential risk factors for the development of loneliness.
In summary, a factor that the studies have in common is that they collected their data during the height of the COVID-19 pandemic and lockdowns or other significant restriction measures. Furthermore, many of them are retrospective, collecting their data only at one point, and an investigation of the change in loneliness in a range of subgroups (e.g., by age) is mostly missing. In Germany in particular, there is still a lack of studies investigating loneliness in students in general and especially comparing loneliness based on representative samples both before and after the COVID-19 pandemic.
The present study aims to fill this research gap and examine the following research questions:
1. Research Question: How did the prevalence of loneliness in children and adolescents change from 2018 to 2022?
2. Research Question: How did loneliness change from 2018 to 2022 depending on gender, grade level, and family affluence?