Journal of Child and Family Studies
https://doi.org/10.1007/s10826-020-01804-3
ORIGINAL PAPER
Trajectories of Early Adolescent Loneliness: Implications for Physical
Health and Sleep
Alice M. Eccles
1
Pamela Qualter
2
Margarita Panayiotou
2
Ruth Hurley
1
Michel Boivin
3
Richard E. Tremblay
4
© The Author(s) 2020
Abstract
The current study examines the relationship between prolonged loneliness, physical health, and sleep among young
adolescents (1013 years; N = 1214; 53% girls). Loneliness was measured at 10, 12 and 13 years of age along with parent-
reported health and sleep outcomes. Using growth mixture modelling, 6 distinct trajector ies were identied: low increasing
to high loneliness (n = 23, 2%), high reducing loneliness (n = 28, 3%), medium stable loneliness (n = 60, 5%), medium
reducing loneliness (n = 185, 15%), low increasing to medium loneliness (n = 165, 14%), and low stable loneliness
(n = 743, 61%). Further analyses found non-signicant differences between the loneliness trajectories and parent-report
health and sleep outcomes including visits to health professionals, perceived general health, and sleep quality. The current
study offers an imp ortant contribution to the literature on loneliness and health. Results show that the relationship may not be
evident in early adolescence when parent reports of childrens health are used. The current study highlights the importance of
informant choice when reporting health. The implications of the ndings for future empirical work are discussed.
Keywords Loneli ness
Health
Adolescent
Longitudinal
Sleep
Highlights
Six distinct trajectories of loneliness were identied in a large, representative sample.
Novel examination of loneliness and parent-reported sleep and health outcomes.
Highlights the importance of measurement and informant choice for future work.
Loneliness is a negative emotional state caused by a dis-
crepancy between a persons desired and actual social
relationships (Peplau and Perlman 1982). Loneliness is
related, but distinct from social isolation (Smith and Victor
2019); it is characterised by dissatisfaction with current
relationships (Cacioppo and Cacioppo 2014) and a feeling
of emotional or physical disconnection from others (Qualter
et al. 2015). It involves uncomfortable feelings, including
sadness, which people try to alleviate quickly by recon-
necting with others. Among adults, those feelings contribute
to reductions in well-being, which for those who experience
loneliness frequently contributes to lower reports of quality
of life, and poorer overall physi cal and mental health
(Leigh-Hunt et al. 2017). Much of the research linking
loneliness and poor health is focused on adults and there is
limited examination of the imp act of prolonged loneliness
on physical health and sleep among adolescents. The cur-
rent study addresses that gap in the literature, extending our
understanding of distinct developmental trajectories of
loneliness in adolescence and their impact on health.
Loneliness is a common experience throu ghout life,
peaking when there are substantial changes to our social
environments (Qualter et al. 2015). Loneliness is considered
a normative reaction to those changing social circumstances
* Alice M. Eccles
1
School of Psychology, University of Central Lancashire, Preston,
Lancashire, UK
2
Manchester Institute of Education, University of Manchester,
Oxford Road, Manchester, UK
3
Université Laval, ,Québec QC G1V 0A6, Canada
4
The University of Montreal, Québec, Canada
Supplementary Information The online version of this article
(https://doi.org/10.1007/s10826-020-01804-3) contains supplementary
material, which is available to authorised users.
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and psychological challenges; people are motivated to
connect with others, nding groups to which they can
belong and make friends with people they can trust. There
are two life periods adolescence and old agechar-
acterised by major changes to social environments, where
increased social needs and expectations increase sensitivity
to feelings of loneliness (Victor and Yang 2012). Loneliness
has been examined extensively among those in old age, but
there is limited work exploring loneliness among youth
despite empirical literature showing the experience is
common among adolescents (Qualter et al. 2015 ). Recent
data from population surveys (Australian Loneliness Report
2018; CIGNA 2018;Ofce of National Statistics 2018),
charity reports (Coop Foundation 2018; Grifn 2010), and
academic research (BBC Loneliness Experiment 2018)
shows that feelings of loneliness are common among ado-
lescents and young adults. Given the evidence that lone-
liness is a particular issue for youth, there is a need to
explore how it impacts their lives: is it the case that the
same health effects of loneliness found among the elderly
are also eviden t among youth.
Peer relationships become increasingly important during
early adolescence (Rubin et al. 2006): concerns relating to
social standing begin to emerge (Haller et al. 2014), inter-
actions with peers increase, and independence from parents
occurs (Smetana et al. 2015); such increased focus on peers
amplies feelings of difference, increasing loneliness. Most
adolescents navigate those normative feelings of loneliness,
but empirical evidence suggests there are small groups of
individuals who are at risk of prolonged feeling of lone-
liness during those crucial years (Harris et al. 2013;
Jobe-Shields et al. 2011 ; Ladd and Ettekal 2013; Qualter
et al. 2013; Schinka et al. 2013; Vanhalst et al. 2013).
Overall, the ndings suggest that the vast majority of youth
experience consistently low or moderate levels of loneliness
and only a small minority suffers from chronically high
levels of loneliness. While there is a growing body of evi-
dence to support the presence of distinct loneliness trajec-
tories, there is a need for further research that examines
loneliness over time and whether following certain trajec-
tories of loneliness predicts important developmental out-
comes, including physical healt h and sleep.
The relationship between loneliness and physical health
has been well researched among adults (for reviews see Holt-
Lunstad et al. 2015; Valtorta et al. 2016)withprolonged
loneliness leading to increasing blood pressure (Hawkley
et al. 2006), higher incidence of coronary heart disease
(Thurston and Kubzansky 2009), and poorer perceived gen-
eral health (Nummela et al. 2011; Segrin and Domschke
2011) and health complaints, such as migraines (Christiansen
et al. 2016). Continued activation of physiological systems,
including the hypothalamicpituitaryadrenocortical (HPA)
axis, contribute to inammatory processes and are thought to
be the leading mechanism by which loneliness is linked to ill-
health (Hawkley and Cacioppo 2010).
Within young populations, most research has used con-
current data and shown that higher levels loneliness are
associated with higher odds of reporting headaches and
stomach aches (Stickley et al. 2016), and poorer self-
reported health (Eccles et al. 2020; Lohre 2012). The cross-
sectional nature of those studies is a problem because such
an approach fails to consider individual variation in the
experience of loneliness over time. Given the growing body
of research that highlights that it is prolonged loneliness that
links to poor health, it is crucial to distinguish between
those who are chronically lonely and others for whom
loneliness is a transitory experience. Among older adoles-
cent samples, prolonged loneliness predicted later self-
reported health (Qualter et al. 2013; Harris et al. 2013), was
a metabo lic risk factors associated with cardiovascular
disease (Goosby et al. 2013), and increased the number of
GP visits (Qualter et al. 2013). Work is needed to explore
how young adolescents following different trajectories of
loneliness differentially experience health.
As well as explore different trajectories of loneliness
and how those link to health, it is i mportant to control for
earlier health reports in any exploration of how loneliness
predicts poor health: self-reported health is stable from
early adolescence th rough to young adulthood (Foss e and
Haas 2009), and without controlling for earlier poor health,
any analysis that explores the prospe ctive link betwe en
loneliness and health is not rob ust. Such robustness is
missing from the extant empricial work. In addition, the
growing body of evidence that expo sure to poverty during
early childhood is a ssociated with a w ide variety of adult
health conditions irrespective of concurrent deprivation
status (Braveman and Barclay 20 09), means there is a need
to control socioeconomic status (SES) and family afuen ce
when examining the effects of l oneliness on later health.
Seguin et al. (2012) examined the trajectory of so cio-
economic status, including family income, using the
QLSCD data from baselines through to 10 years o f age.
The trend da ta suggests the pre valence of poverty during
childhood declines over time with fewer children living
with families with low income or receiving state support.
Despite that increase in family afuenc e, Se quin hig hlights
how early poverty, despite the increase in afuen ce later in
childhood, has detrimental impacts upon subseque nt health
as illustrated by previous research (Braveman et al. 2011;
Luo and White 2005; Poulton et al. 2002). Given ndings
that ea rly childhood SES is associated with an elevated risk
of mortality in adulthood, regardless of the individuals
current SES status (Galobardes et al. 2008), it is important
to account for early exposure to social ine qua lity that might
shapefuturebarriersinlifethatimpacthealth(Ferraro
et al. 2016).
Journal of Child and Family Studies
As well as physical h ealth, social stress is linked to
disturbed sleep (Dahl and Lewin 2002), suggesti ng that
loneliness may be counterproductive to a good nights
sleep. Loneliness signals to an individual to change
something about their social environment. As such, it
leads to an increased vigilance to social cues and
increased activation of the HPA axis in response to that
social stre ss (Haw kl ey and Cac ioppo 2010). Previous
research supports that idea: loneliness is not a ssociated
with the overall sleep quantity, but it affects overall
quality of the sleep among adults (Cacioppo et al. 2002;
Kurina et al. 2011). Extant literature that has used pro-
spective designs shows loneliness over time strongly
predicts poor sleep quality among adults (Hawkley et al.
2010). Despite empirical work examining the relationship
between loneliness and sleep among adults, there is a
paucity of research examining that association among
youth. In older adolescents, loneliness has been associated
with subjective sleep outcomes such as quality and day-
time dysfunction (Matthews et al. 2017), but not related to
objective measures such as sleep duration and latency
(Doane and Thurston 2014). Majeno et al. (2018)high-
light the importance of loneliness and social stress, sug-
gesting loneliness partially mediates the relationship
between discrimination and sleep in adolescents.
In early adolescents, loneliness has been found to be
associated with increased difculties and experiences of
disturbed sleep, but not will overall sleep quantity (Eccles
et al. 2020). Whilst those previous studies support an
association between loneliness and sleep, they all examine
concurrent data. There is little research examining the
relationship over time. In 811 year olds, Harris et al.
(2013) showed that children experiencing a relatively high
reducing loneliness reported greater sleep disturbance
compared to children who followed a low, stable trajectory
of loneliness. Such work with children suggests that lone-
liness may impact sleep, even when social reconnection
occurs. There is a need to further investigate whether dif-
ferent trajectories of loneliness among youth relate to sleep
outcomes. Such work will establish whether loneliness over
timeis associated with poorer sleep quality consistently
across different samples of youth.
Another important aspect to consider is the use of parent
reports of their childs health, which is commonplace in the
literature (Garbarski 2014). The use of proxy reports and the
agreement with self-reported outcomes has been extensively
researched and ndings have been mixed (Smith and
Goldman 2011; Todd and Goldman 2013). Nolan (2016)
examined both parent and child report health utilising data
collected in the Young Lives survey: moderate correlations
between the two informants support convergent validity;
parent reports also displayed a stronger association with
physical health indicators such as height. There is evidence
to suppor t parental-proxy reports of health and their use
warrants further attention.
The current study examined the presence of distinct
developmental trajectories of loneliness in a sample of
Canadian adolescents aged 1013 years. First, we examined
how loneliness changed over the course of late childhood
and early adolescence for the whole sample. Second, we
explored whether youth followed particular trajectories of
loneliness, and whether those following particular trajec-
tories of loneliness experienced poorer health and sleep
problems. Our overall aim was to provide data on the
prospective associations between loneliness, physical
health, and sleep among young adolescents. We controlled
for earlier health problems and early family income in our
analyses to determine the uniqueness of loneliness in pre-
dicting health and sleep outcomes.
Method
The data used in the current study were collected as part of
the on-going Québ ec Longitudinal Study of Child Devel-
opment (QLSCD). The QLSCD is a large birth cohort study
organised by the Direction Santé Québec of the Institut de
la Statistique du Québec. The prospective study includes
singleton infants born in the Canadian provinces of Québec
between 1997 and 1998. The QLSCD study took baseline
measurements from 2223 infants and mothers when infants
were between the ages of 15 and 36 weeks (mean age of
5 months). The study continued to collect data, on an annual
or biannual basis, and is still an active research project. The
current study focused on data collected when the partici-
pants were ages 10, 12, and 13 years (in the current study,
referred to as Times 1, 2, and 3 respectively). The QLSCD
received ethical approval from the ethics committee of the
Faulty of Medicine, the University of Montreal and the
Direction Sa nte Quebec, Institu t de la Stati stique du
Quebec.
Participants
In the current study, only participants who completed the
loneliness questions at Time 1 of the current study (age 10
years) and at least one other time point (age 12 or 13 years)
were included in the study. A total of 1214 children (53%
female) met those criteria , with 13.45% missing data. Lit-
tles(1988) Missing Completely at Random (MCAR) test
suggested data were not MCAR (χ
2
(2116) = 2762.12, p <
0.001), but following recommendations (Enders 2010;
Muthen and Muthen 19982020), we computed missing
data using FIML on the latent loneliness variables in the
growth curve analysis. Missing data on the distal outcomes
were imputed using multiple imputation (following
Journal of Child and Family Studies
guidelines provided by Asparouhov and Muthen 2010).
Data imputation is typically less biased than other techni-
ques such as list wise deletion (Schafer and Graham 2002).
Procedure
Data used in this study were collected from both the ado-
lescents and their mothers. Youth completed the loneliness
questions when they were ages 10, 12, and 13 years
respectively. At the same time points, mothers completed
measures that asked about their childs sleep and physical
health. Parental socio-economic status data were collected
from the mother when the children were 17 months olds.
Measures
Loneliness
Children were asked to rate, using a 3-point likert scale
(1 = never,2= sometimes, and 3 = always) how often they
had felt the following in the past 2 weeks: (1) I have no one
to talk to, (2) I feel alone, and (3) I feel left out. Those three
items are similar to those in the 3-item short form of the
UCLA (Hughes et al. 2004). The three item scores were
summed, creating an overall loneliness score with total
scores ranging from 3 to 9. Higher scores represented higher
loneliness. The loneliness measure demonstrated reasonably
good internal reliability at all three time points (T1α =
0.67; T2α = 0.68; T3α = 0.73).
Physical health
The current study includes variables relating to mothers
perceptions of their childs physical health. Perceived
general health. Mothers were asked to rate their childs
current general healt h (1 [ Excellent]5[Poor]), such that a
higher score represented poorer general health. Health
professional visits. Mothers indicated which of the follow-
ing health professionals they had consulted in the past
12 months about their childs health: general practitioner,
paediatrician, medical doctor and/or public health nurse.
The number of health professionals the mother had con-
sulted was summed. A higher score indicated that the child
had visited a higher number of different health profes-
sionals. Antibiotic Use. Mothers indicated how many times
their child had taken a course of antibiotics in the past
6 months. They used the following 6-point scale: 1 = none,
2 = once,3= twice,4= 3 times ;5= 4 or more,6= one or
more long term antibiotics, and 7 = continuous treatment .
Infection rates . Mothers were asked which of the following
infections their child had suffered from in the past three
months: gastro-intestinal, ear, bronchitis/pneumonia, cold/
u/laryngitis, and other infections. A total number of
infections variable was created, with a higher score indi-
cating a higher frequency of infections.
Sleep
For sleep behaviour, mothers were asked about the quality
and quantity of their childs sleep. For sleep quality,
mothers were asked whether their child was drowsy or
sleepy during the day with a higher score representing
poorer quality sleep (1 = Never to 4 = Always). For sleep
quantity, mothers were asked to indicate how long in total
their child slept during the night (on average); they provi ded
answers in hours and minutes. Sleep quantity was calculated
in half hour intervals.
Family Income
When children were 17 months old, mothers provided
information on household income, household size, and type
of family residence. That information was used to calculate
income sufciency using the Statistics Canadasdenition
of low income, which considers the number of people in the
household and the family zone of residence. Family income
was coded as sufcient (1) or insufcient (2).
Data Analyses
First, we examined the prevalence of loneliness among the
current sample and explored bivariate correlations between
all variables. Next, we explored the changes in loneliness at
the group level for chil dren in the QLSCD when they were
ages 1013 years using latent growth curve modelling
(LGCM). LGCM enabled us to estimate the initial level of
loneliness at baseline (intercept) and the degree of change in
loneliness from baseline across the time of the study (slope).
Factor loadings were xed at 0, 2, 3 to represent the time
difference between measurements. The model t was
assessed using common t indices: chi square index, Root
Mean Square Error of Approximation (RMSEA: should be
less than 0.07; Steiger 2007), and Comparative Fit Index
(CFI: a value of equal or greater than 0.95 is indicative of
good t; Hu and Bentler 1999). Next, using latent class
growth analysis (LCGA; Jung and Wickrama 2008), we
explored whether there were sub groups of children that
followed distinct trajectories of loneliness from ages 1013
years, and whether that differential development predicted
health and sleep outcomes controlling for earlier health and
family income. In the rst stage of LCGA, the basic model
was tested, exploring only the trajectories of loneliness and
without any control variables. The optimal number of
groups following distinct trajectories of loneliness was
determined by comparing K-Class and K-1 class model
based on Bayesian Information Criterion (BIC), sample-size
Journal of Child and Family Studies
adjusted Bayesian Information Criterion (aBIC), and
Akaikes Information Criteria (AIC). A lower BIC, aBIC,
and AIC are indi cative of a better t (McLachlan and Peel,
2000). Class number was also evaluated using the Lo-
Mendell-Rubin likelihood ratio test (LMRT) and entropy.
For LMRT, a signicant p value suggests the model was
signicantly improved by the additional class when com-
pared to previous solution; for entropy, a value close to 1
indicates less classication error and therefore representing
a better t (Nagin and Odgers 2010). The optimal number
of groups was also determined based on theoretical under-
pinnings and previous ndings (Nagin and Odgers 2010)to
ensure substantive meaning to the ndings. In the second
stage of the LCGA, the relations between the groups fol-
lowing distinct trajectories of lonel iness and later health and
sleep outcomes were examined using the BCH approach
(Bolck et al. 2004; Bakk and Vermunt 2016) in Mplus V8.
BCH estimated the mean differences in health and sleep
between the different trajector y classes using Walds chi
square test (Asparouhov and Muthén 2014). In the second
stage of the LCGA, we controlled for earlier reports of
family incom e and baseline measures of health in the
model. All models were run in Mplus V8 (Muthen and
Muthen 19982020). We followed van de Schoot et al.
(2017)s recommendations for writing up the analysis.
Results
Demographics
Table 1 includes variable information for the 1214 partici-
pants whose data wer e analysed. Of those participants, 54%
identied as Canadian , 15% were French, 21% identied as
both; the remaining 10% were from other ethnicities. The
majority of the sample came from homes that had been
classied as having sufcient income to meet basic needs
when the child was 17 months of age. Descriptive statistics,
including correlations within and between variables, as well
as additional analysis relating to SES stabilities, are outlined
in Supplementary Tables S1, S2.
Changes in Loneliness Over Time
Results from LGCA showed a signicant intercept (β0 =
3.82, p < 0.001) and a non-signi cant slope (β1 = 0.008,
p = 0.568), such that participants on average scored 3.82 on
the loneliness scale a t baseline, and stayed relatively stable
over time (χ
2
(3) = 242.65, p < 0.001, CFI = 0.98, RMSEA
= 0.07, CI = 0.0240.118). The results demonstrated a
signicant variance in the intercept (0.36, p = 0.014) and
some variation for slope (0.30, p = 0.018), justifying the
examination of different trajectories of loneliness.
Using LCGA, two through to seven-class solutions for
loneliness were estimated, with Table 2 outlining the t
indices. Considering the model t indices, and the theore-
tical underpinnings and minimal class size recommenda-
tions (Class k >1% of N; Jung and Wickrama 2008), a 6-
class solution t the data best.
The six distinct loneliness trajectories are as follows: low
increasing to high lonelines s ( n = 23, 2%), high reducing
loneliness (n = 28, 3%), medium stable loneliness (n = 60,
5%), medium reducing loneliness (n = 185, 15%), low
increasing to medium loneliness (n = 165, 14%), and low
stable loneliness (n = 743, 61%; see Table 3 and Fig. 1).
Children following a low increasing to high loneliness
trajectory reported low levels of loneliness at 10 years old,
but reported increasingly levels of loneliness across the
three years resulting in a high level of loneliness at age 13.
Table 1 Early Family Income and Loneliness reports for all
participants (N = 1214)
% of sample N
Early Family Income
Sufcient 80% 971
Insufcient 20% 243
Time point 1 Time point 2 Time point 3
Mean age in years
a
10.14 12.13 13.13
Mean loneliness
(range is 39)
3.84 (1.42) 3.79 (1.41) 3.89 (1.65)
Mean loneliness scores based on sum score of T1, T2, and T3
loneliness scores. Data on early family income was collected when the
children were aged 17 months. Income sufciency was dened using
the Statistics Canadasdenition of low income, whilst also
considering the number of people in the household and the family
zone of residence. The low-income cut-off used by Statistics Canada is
an income level from which, on average, a person (or family) spends
20% more of their total income on food, shelter, and clothing than is
spent by similar persons or families in similar locations (https://www
150.statcan.gc.ca/n1/pub/75f0002m/2012002/lico-sfr-eng.htm)
a
Mean age calculated for those who provided data at the corresponding
time points (T1: 1180; T2 = 1186; T3 = 1099)
Table 2 Model Fit Indices for 2 through 7 class solutions
Class AIC BIC Adj BIC Entropy LRT
p value
n
2 10,531.49 10,577.40 10,548.82 0.871 <0.001 204
3 10,318.77 10,379.99 10,341.875 0.856 0.037 130
4 10,101.22 10,177.74 10,130.09 0.907 0.050 58
5 9908.07 9999.90 9942.73 0.924 0.002 40
6 9770.46 9877.59 9810.89 0.931 0.001 23
7 9681.43 9803.87 9727.63 0.939 0.061 17
AIC Akaikes Information Criteria, BIC Bayesian Information Criter-
ion, Adj BIC adjusted Bayesian Information Criterion, Entropy, LRT
Lo-Mendell-Rubin likelihood ratio test Value, N number of individuals
in the smallest class
Journal of Child and Family Studies
Children following the high reducing lonel iness trajectory
reported relatively high levels of loneliness when they were
10 years of age, but that reduced over the next 3 years to
average levels of loneliness. Children following the medium
stable loneliness had relatively stable, but moderate, levels
of loneliness over the three years. Those following the
medium reducing trajectory reported average levels of
loneliness at ten years of age, which reduced to lower than
average over the next three years. Those children following
the low increasing to medium loneliness trajectory reported
low levels of loneliness at age 10 years and increased on
loneliness steadily, to an average level of loneliness, over
the next three years. The majority of children followed the
low stable loneliness trajectory reporting low levels of
loneliness from ages 1013 years.
Using the BCH approach, the mean differences on ado-
lescent health and sleep outcomes across the six different
trajectories of loneliness were estimated. To control for
Type 1 errors, a conservative adjusted alpha of <0.001 was
used for all comparisons. In this step, we also controlled for
the effects of earlier family income and health on later
health and loneliness As shown in Table 4, we found no
signicant differences in physical health and sleep com-
plaints between children who followed different trajectories
of loneliness from 1013 years.
Discussion
The current study examined the presence of groups of
adolescents who followed distinct trajectories of loneliness
from ages 1013 years, with the aim of exploring the pro-
spective link between prolonged loneliness and physical
health and sleep outcomes among youth. We controlled for
the impact of early family income, as a known predictor of
poor health outcomes among adolescence and for earlier
reports of poor health, exploring loneliness as a unique
predictor of poor health and inadequate sleep. We found six
distinct trajectories of loneliness—‘Low Increasing to
Medium, Medium Reducing, High Reducing, Low,
Low Increasing to High and Medium Stable’—but there
was no support for the hypothesis that increasing or main-
tained loneliness was related to poorer health outcomes as
reported by the mother. Given ndings that loneliness is
linked to poor health and sleep quality among adults, we
discuss why we have diff erent ndings for youth in the
current sample. We discuss why it might be the case that
young adolescents who report higher loneliness, and parti-
cularly those in the current sample, might have mothers who
do not report them as experiencing poor health and sleep
outcomes.
Adolescents in the current sample followed one of six
distinct trajectories of loneliness from 10 to 1 3 years of
age: (1) Low Increasing to Medium,(2)Medium
Reducing,(3)High Reducing,(4)Low Stable,(5)
Low Increasing to High and (6) Medium Stable.The
low stable group explained the loneliness experience for
the majority of the participants (61%), supporting previous
research examining distinct trajectories of loneliness
across adolescence (Harris et al. 2013;Jobe-Shieldsetal.
2011; Ladd and Ettekal 2013; Qualter et al. 2013; Schinka
et al. 2013;Vanhalstetal.2013). The current sample did
not include a group of adolescents who followed a high
stable trajectory of loneliness, a group found in some of
the previous research (Ladd and Ettekal 2013;Qualter
et al. 2013; Schinka et al. 2013
), but there was evidence
that some children followed a trajectory characterised by
high reducing loneliness, and others followed a trajectory
of low increasing to high loneliness. The most li kely
explanation for not nding a group of adolescents
experiencing prolonged loneliness is the relatively low
levels of loneliness reported by the current sample. Given
other recent data suggesting that loneliness is a signicant
Table 3 Loneliness mean scores at ages 10, 12 and 13 years for the 6-
class solution
n%of
N
10 years 12 years 13 years
Low Increasing
to Medium
165 14 3.32 4.32 5.44
Medium Reducing 185 15 5.31 3.71 3.61
High Reducing 38 3 7.46 4.68 4.39
Low Stable 743 61 3.25 3.41 3.20
Low Increasing to High 23 2 3.77 5.76 8.05
Medium Stable 60 5 5.77 5.57 6.35
The range of scores on the loneliness measure is 3 to 9, with 9
representing high reports of loneliness
3
4
5
6
7
8
9
10 year
s 12 years 13 years
Low Increasing Medium
Medium Reducing
High Reducing
Low Stable
Low increasing high
Medium Stable
Fig. 1 Estimated mean trends for the six loneliness trajectory classes
Journal of Child and Family Studies
issue for adolescents (for example, Ofce of
National Stat isti cs 2018), it becomes i mportant to deter-
mine what is different about the current sample that makes
these adolescents report lower levels of loneliness; given
the current study includes a representative sample of youth
we need further study to understand what might be dif-
ferent about the experiences of youth in Quebec or Canada
that sets them apart from adolescents from other countries
where reports of loneliness among youth are much higher.
It is also note-worthy that the loneliness measure utilised
in the current study is different from those in previous
research, and may explain why higher levels of loneliness
were not captured within the sample.
We did not nd support for prospective relationships
between loneliness and physical health and loneliness and
sleep outcomes: adolescents in the current study following
the different trajectories of loneliness did not signicantly
differ on the health and sleep outcomes. Previous research
that examined different pathways of loneliness reported
signicant differences between distinct loneliness trajec-
tories on health and sleep outcomes (Harris et al. 2013;
Qualter et al. 2013), but our ndings do not support that
earlier work. The lack of relationship between self-reported
loneliness and parent-reported health outcomes could be for
a number of reasons. First, it may be that mothers do not
accurately report the health and sleep of their children.
Indeed, previous research suggests mother may under-
estimate sleep problems within children and adolescents
(Fatima et al. 2016) with up to one third of potential sleep
problems remaining unnoticed (Paavonen et al. 2000).
Second, the negative cognitive bias and affect associated
with loneliness could extenuate discrepancies between
informants. Although adolescents are typically accurate at
reporting their own physical health (Riley 2004), there is
evidence to suggest adolescents are much less optimistic
about their health than their parents as a result of a sensi-
tivity or mental health problem the parents is not aware of
(Waters et al. 2003). It may be the case that self-reported
health provides a window into the internal lives of the
youth (Johnson and Wang 2008); adolescents reporting
loneliness are pessimistic and negative in their reections,
and that includes their health, supporting previous asso-
ciations between youth loneliness, health and sleep (Qualter
et al. 2013; Stickley et al. 2016; Matthews et al. 2017;
Harris et al. 2013; Eccles et al. 2020). Further research
should investigate the impact of different informants,
including parents and health professionals, to help deepen
our understanding about the true relationship between youth
loneliness and health.
The current study offers an important contribution to the
literature on loneliness and health. We showed that the
relationship may not be evident in early adolescence when
parent reports of childrens health are used. However, the
study is not without limitations. It is important to note the
health measures were not from a validated scale, and the
current research could be extended through the use of more
objective measures of sleep, (e.g. sleep caps) and health
biomarkers and cortisol). Extending research examining the
relationship between youth loneliness and health and/or
sleep through more objective measures, to mirror those used
in adult literature, will help provide a deeper understanding
behind the relationship as well as insight into the underlying
mechanisms.
It is also important to recognise the overall levels of
loneliness reported in the current sample are low. Given the
reliability of the loneliness measure used it the current study,
the current study highlights the importance of measurement
choice. There are arguments for using short measures of
loneliness with restricted response scales, but there are
counterarguments that such measures do not truly capture the
experience of youth loneliness (Eccles et al. 2020
). However,
Eccles et al. showed that associations between loneliness and
health/sleep complaints were robust across the longer and
shortened version of the UCLA when used with adolescents,
Table 4 Trajectory means and comparisons on physical health and sleep outcomes, controlling for early family income and health outcomes
Low Increasing to Medium Medium Reducing High Reducing Low Stable Low Increasing to High Medium Stable
Visits to Professionals 1.57 1.06 1.60 1.30 2.28 2.65
Perceived Health 0.72 0.95 0.76 0.68 0.90 0.26
Infection Rates 5.51 4.98 3.28
a
5.10 5.04 4.75
Antibiotic Use 1.06 1.06 0.78 0.89 1.32 1.14
Daytime Drowsiness 0.97 0.73 0.61 0.66 1.34 0.79
Overall Sleep Quantity 36.26 33.58 35.98 33.44 34.48 30.73
No comparison demonstrated a signicant factor as indicated by p > 0.05
Mothers reported on all health complaints. All values reported for the outcomes are standardised residuals. Differences across proles on T3/age 13
outcomes were obtained after controlling for earlier reports of respective physical health/sleep complaints (measured at T1/age 10) and early family
income effects (data collected when the child was 17 months old)
Analysis were also completed without Earlier Family Income as a control and the results did not differ
a
High reducing trajectory demonstrated lower rates of infection than the low stable (p = 0.010), medium reducing (p = 0.051) and low increasing
(p = 0.004). However, to control for Type 1 errors, these comparisons failed to reach the Bonferroni adjusted p < 0.001
Journal of Child and Family Studies
suggesting that short measures such as that used in the cur-
rent study should not represent a problem because they
measure loneliness accurately. However, more research using
both standard and shortened versions of loneliness measures
are needed so the potential impact of how we measure
loneliness can be examined. To help overcome that potential
limitation, it is important that future work gathers prevalence
and cross-national survey data relating to the presence,
experience, and feeling of loneliness amongst young people,
and the associated health outcomes.
With the limitations considered, the current study still
offers a valuable contribution to the literature and has many
merits. The study retains a large sample size throughout the
analyses, and utilises a robust statistical method that con-
sidered the health differences between groups following
different trajectories of loneliness, allowing for full analysis
in one statistical programme (Bakk and Vermunt 2016). The
longitudinal nature of the study is certainly a strength,
enabling the examination of the relationship between lone-
liness and health outcomes over a prolonged period of time;
the control of early family income and health also ensured
robust control of important related constructs. The current
study examined the prospective association between lone-
liness, physical health, and sleep, and we provided a robust
design by controlling for early reports of family income and
child health that have been shown to impact later health
outcomes. Contrary to research with adults, we did not nd a
relationship between increasing loneliness and poor health
and sleep quality. That was, to some extent, a reection of
the fact that young adolescents in the current representative
sample of Canadian youth did not report high levels of
loneliness. Future research will want to (1) explore feelings
of loneliness in different groups to establish whether high,
stable loneliness over time impacts health negatively, and (2)
gather prospective health data from multiple sources,
including via objective measurement, to explore whether the
relationship between loneliness and poor health is primarily
driven by self-perceptions.
Acknowledgements This study uses data from the Quebec Long-
itudinal Study of Child Development (QLSCD). Data collection for the
QLSCD was made possible through funding from the ministère de la
Santé et des Services Sociaux (MSSS) (Ministry of Health and Social
Services), the Lucie and André Chagnon Foundation, the ministère de
la Famille (Ministry of Family), and the Institut de la statistique du
Québec (the Institut).
Author Contributions A.E. conceived the study, performed statistical
analyses, interpreted the ndings, drafted the manuscript and made
revisions to the manuscript based on reviewer feedback; P.Q. con-
ceived the study, helped to perform statistical analyses, interpret the
ndings, and contributed to the draft manuscript; M.P. and R.H.
helped to perform statistical analyses and interpret the ndings, and
contributed to the draft manuscript; M.B. and R.E.T. participated in the
study design, and edited the manuscript; M.B. and R.E.T. coordinated
the original data collection. All authors read and approved the nal
manuscript.
Data Sharing and Declaration The dataset analysed during the current
study is not publicly available; It is available from Institut de la sta-
tistique du Québec (Information and Documentation Centre, Institut de
la statistique du Québec, 200, chemin Sainte-Foy, 3e étage Québec
(Québec, G1R 5T4).
Compliance with Ethical Standards
Conict of Interest The authors declare that they have no conict of
interest.
Ethical Approval All procedures performed in studies involving
human participants were in accordance with the ethical standards of
the institutional and/or national research committee (include name of
committee + reference number) and with the 1964 Helsinki
declaration and its later amendments or comparable ethical standards.
Informed Consent Informed consent was obtained from all individual
participants included in the study.
Publishers note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional afliations.
Open Access This article is licensed under a Creative Commons
Attribution 4.0 International License, which permits use, sharing,
adaptation, distribution and reproduction in any medium or format, as
long as you give appropriate credit to the original author(s) and the
source, provide a link to the Creative Commons license, and indicate if
changes were made. The images or other third party material in this
article are included in the articles Creative Commons license, unless
indicated otherwise in a credit line to the material. If material is not
included in the articles Creative Commons license and your intended
use is not permitted by statutory regulation or exceeds the permitted
use, you will need to obtain permission directly from the copyright
holder. To view a copy of this license, visit http://creativecommons.
org/licenses/by/4.0/.
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