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PAPER
Bereaved mothers' and fathers' prolonged grief and
psychological health 1 to 5 years after loss—A nationwide study
Lilian Pohlkamp
1
|Ulrika Kreicbergs
1,2
|Josefin Sveen
1,3
1
Department of Health Care Sciences,
Palliative Research Centre, Ersta Sköndal
Bräcke University College, Stockholm, Sweden
2
Department of Women's and Children's
Health, Karolinska Institutet, Stockholm,
Sweden
3
Department of Neuroscience, Psychiatry,
Uppsala University, Uppsala, Sweden
Correspondence
Lilian Pohlkamp, Department of Health Care
Sciences, Palliative Research Centre, Ersta
Sköndal Bräcke University College, Stockholm,
Sweden.
Email: lilian.pohlkamp@esh.se
Funding information
Barncancerfonden, Grant/Award Number:
PR2015‐0050; TJ2015‐0021; Ersta Sköndal
Bräcke University College; Gålö Foundation;
Swedish Childhood Cancer Foundation, Gålö
Foundation, and Ersta Sköndal Bräcke Univer-
sity College
Abstract
Objective: To assess differences in prolonged grief, depression, posttraumatic
stress, and sleep disturbances in bereaved parents across years since loss (1‐5 years)
and by gender and to assess potential interactive effects of time since loss and gender
on bereavement outcomes.
Methods: This study examined symptom levels of prolonged grief disorder, depres-
sion, posttraumatic stress, and insomnia in bereaved parents. A sample, including 133
mothers and 92 fathers who had lost a child to cancer 1 to 5 years previously,
subdivided to five subsamples, one for each year since loss. Analysis of variance
(ANOVA) was used to assess differences in symptom levels, related to years since
loss, and gender.
Results: Regardless of how many years had passed since the loss, symptom levels
of prolonged grief, depression, posttraumatic stress symptoms, and insomnia were
elevated in all subsamples. Mothers showed higher symptom levels of prolonged
grief, depression, and posttraumatic stress than fathers. However, no significant
interaction effects were found between years since loss and gender on any of the
symptom levels.
Conclusions: Cancer‐bereaved mothers and fathers are vulnerable to prolonged
grief and psychological symptoms up to 5 years after the death of their child. Findings
highlight that bereaved parents may need long‐term support, and the results deserve
further attention in research and clinical care.
KEYWORDS
childhood cancer, depression, fathers, mothers, insomnia, pediatric oncology, PGD, posttraumatic
stress, prolonged grief
1|INTRODUCTION
The death of a child violates the perceived order of living in the family
life cycle; combined with strong attachment bonds, it puts parents at
increased risk for severe suffering and an elevated risk for developing
prolonged grief disorder (PGD) and other negative psychological
health outcomes.
1,2
Grief reactions in PGD are essentially similar to
those in natural grief, but when separation distress is so persistent
and pervasive that it impairs the bereaved person's functioning in daily
life more than 6 months after the loss, a PGD diagnosis may be appli-
cable according to ICD‐11.
3
A recent meta‐analysis reported a pooled
PGD prevalence rate of 10% in nonviolent adult bereavement,
4
but
PGD prevalence rates tend to be higher in samples of bereaved
parents.
5,6
Common psychological symptoms associated with bereavement
are depression, posttraumatic stress, and insomnia.
7
Although
prolonged grief, depression, and posttraumatic stress are strongly
related, they are distinguishable concepts.
8
Evidence of this
Received: 25 February 2019 Revised: 6 May 2019 Accepted: 13 May 2019
DOI: 10.1002/pon.5112
Psycho‐Oncology. 2019;1–7. © 2019 John Wiley & Sons, Ltd.wileyonlinelibrary.com/journal/pon 1
distinctiveness includes a longitudinal study on bereaved couples,
showing that grief was predicted by bereavement‐specific factors,
while depression was predicted by individual factors.
9
Although the prevalence of prolonged grief and depression in
bereaved parents is frequently studied, posttraumatic stress and sleep
disturbances have been studied less. A recent review on bereaved par-
ents suggests that the death of an infant is such a traumatic event that
health care professionals should keep in mind the possibility of post-
traumatic stress disorder (PTSD) when meeting bereaved parents.
10
A recent longitudinal study showed elevated levels of posttraumatic
stress symptoms in parents bereaved owing to a child's cancer.
11
While there is a growing body of research on the intensity of grief
reactions and other psychological health problems in parents who
have lost a child to cancer, a recent review found that many of these
studies had small sample sizes or did not use validated measures.
12
Another common health problem associated with bereavement is
sleep disturbance.
13,14
A study
15
reported that fathers were more
likely to have sleep disturbances than mothers were, 4 to 9 years after
the loss of a child to cancer. In addition, disturbed sleep has been
associated with elevated symptom levels of PGD,
16
depression,
17
and posttraumatic stress.
18
Theories on grief and bereavement have evolved during recent
decades; Bowlby's and Parke's pioneering works on separation stage
theory and attachment theory led to greater understanding of
bereavement adjustment.
19,20
They suggested that how grief is expe-
rienced and expressed may be related to individual attachment styles.
Further exploration of these concepts resulted in the formulation of
the dual process model of coping,
21
which is now a leading conceptual
framework for research on coping with bereavement. Coming to terms
with the loss of a child takes time—often years—but few studies have
examined the grief of mothers and fathers in relation to the time since
loss. The aim of this study was to assess differences in prolonged grief,
depression, posttraumatic stress, and sleep disturbances in bereaved
parents across years since loss (1‐5 years) and by gender. A secondary
aim was to assess potential interactive effects of time since loss and
gender on bereavement outcomes.
2|METHODS
2.1 |Design
This cross‐sectional study was based on data from a nationwide postal
Swedish survey.
2.2 |Participants
Eligible parents were identified through the Swedish Childhood Cancer
Registry (a national database on all children who receive a cancer diag-
nosis) combined with the Cause of Death Registry and the Swedish
Population Register at the Swedish Tax Agency. Inclusion criteria were
being a parent of a child (age 0‐24 years) who had died during the
period August 2010 to July 2015 of cancer (age at diagnosis 0‐16
years) in Sweden. At the time of the study, the parent should live in
Sweden and understand Swedish. No significant differences were
found between responders and nonresponders regarding the parents'
age at the time of the study, age at the time of the child's death, years
since loss, child's gender, and child's age at time of diagnosis and death.
The only exception was that the percentage of women was higher
among responders than among nonresponders (X
2
= 8.83, P< .05).
Ethical approval for this study was obtained from the Regional Ethical
Review Board in Stockholm, Sweden (No: 2015/2183‐31/5).
2.3 |Procedure
Eligible parents (N = 512) received an information letter describing the
study's purpose and procedures. All potential participants could con-
tact the research group with questions about the study. Each parent
of each child was contacted separately by telephone and asked
whether he or she would agree to participate. Parents with unlisted
telephone numbers were sent a letter requesting that they contact
us by phone or e‐mail. A second letter of invitation was sent after 1
month to those who had not responded. Seventy‐six parents could
not be reached, 63 declined, and 373 parents consented to participate
and were sent a questionnaire with a prepaid return envelope. Parents
who did not return the questionnaire within 1 month were contacted
by telephone. Of the 373 parents who agreed to participate, 232
returned the questionnaire. Seventy‐six parent dyads were included;
however, we do not know if they were living together at the time of
the study.
2.4 |Measures
The questionnaire was based on an earlier survey
22
and contained
questions on demographics, health care experiences from diagnosis
until the child's death, and family communication. While developing
the questionnaire, eight face‐to‐face validation interviews with
cancer‐bereaved parents were conducted by the first author (L.P.),
and questions were adjusted according to their suggestions.
Prolonged grief disorder‐13 (PG‐13)
23
was used to assess PGD. It
consists of 13 items: two items on duration and impairment that are
to be answered “yes”or “no,”and 11 items assessing cognitive, behav-
ioral, and emotional symptoms experienced during the past month,
rated on a 5‐point frequency scale ranging from: “not at all”to “several
times a day”(scoring 1‐5), or an intensity scale ranging from “not at all”
to “overwhelmingly”(scoring 1‐5). PG‐13 is scored as a continuous
measure by summing the eleven symptom items and excluding the
two duration and functional impairment items.
23
The total score
ranges from 11 to 55, with a higher score indicating more symptoms
of PGD, cut‐off
24
equal to or more than 35. Cronbach's αwas 0.89.
The Montgomery‐Åsberg Depression Rating Scale (MADRS)
25
was
used to assess symptoms of depression. It consists of nine items: sad-
ness, inner tension, reduced sleep, reduced appetite, concentration
difficulties, fatigue, inability to feel, pessimistic thoughts, and suicidal
thoughts. The items are rated on a 7‐point scale (scoring 0‐6), and
2POHLKAMP ET AL.
the total score ranges from 0 to 54, a higher score indicating a greater
risk of depression. Range for mild depression is 13 to 19, moderate 20
to 34 and cut‐off for severe depression equal to or more than 34.
Cronbach's αwas 0.90.
The Posttraumatic Stress Disorder Checklist for DSM‐5 (PCL‐5)
26
was
used to assess symptoms of PTSD. It consists of 20 items divided into
four subscales: intrusion, avoidance, negative alterations in cognitions
and mood, and alterations in arousal and reactivity. The items are
rated on a 5‐point scale (scoring 0‐4), and the total score ranges from
0 to 80, with a higher score indicating more symptoms of PTSD, cut‐
off equal to or more than 33. Cronbach's αwas 0.94.
The Insomnia Severity Index (ISI)
27
was used to assess symptoms of
insomnia and consisted of seven items: severity of problems falling
asleep, staying asleep, early morning awakening problems, sleep dis-
satisfaction, interference of sleep difficulties with daytime functioning,
noticeability of sleep problems to others, and distress caused by the
sleep difficulties. The items are rated on a 5‐point scale from “no
problem”to “severe problem”(scoring 0‐4) and the total score ranges
from 0 to 28, with a higher score indicating more symptoms of insom-
nia, cut‐off equal to or more than 10. Cronbach's αwas 0.94.
2.5 |Data analysis
Significance level for all analyses was P< .05. Characteristics of
responders and nonresponders were compared with Wilcoxon's
rank‐sum test and χ
2
analysis. Spearman correlation analyses and scat-
ter plots were used to evaluate dependency of data, as dyads of par-
ents of the same child were included (ie, 152 of the 232 parents in
the study). Analysis indicated a weak but significant correlation for
MADRS (Spearman's rho 0.26, .03) and a moderate correlation for
PG‐13 (Spearman's rho 0.44, P< .001) between mothers and fathers
of the same child, while the analysis showed no significant correlations
for PCL‐5 and ISI. Since the correlations between dyads were so weak,
the data were treated as independent in the further analyses.
First, descriptive analysis was conducted on demographic charac-
teristics of the total sample. Then, the sample was divided into five
subsamples according to the number of years since loss. Once mean
scores for the subsamples were retrieved, scores for each subsample
were assessed separately for mothers and fathers.
Finally, two‐way analysis of variance (ANOVA) was used to assess
differences in psychological symptom levels associated with years
since loss and parent's gender, as well as interaction effects between
time since loss and gender. IBM SPSS Statistics version 22 was used
for all statistical analysis.
3|RESULTS
3.1 |Sociodemographic characteristics
Demographic characteristics of the parents and deceased children are
summarized in Table 1. At the time of the study the mean age of the
parents was 46.0 years; 133 (59%) were mothers and 92 (41%)
fathers; 196 (87%) parents were either employed or studying, and
126 parents (56%) lived in an urban area. When examining statistical
differences between mothers and fathers with regards to the
TABLE 1 Characteristics of the bereaved parents (n = 225) and
deceased children (n = 151)
Mean (SD) Range
Parent age at study 46.0 (8.15) 24‐66
Parent age at child death 42.2 (8.01) 20‐62
Childs' illness length in years 2.7 (3.51) 0‐21
Years since loss 3.1 (1.47) 1‐5
Characteristics of the parents at the time of the study n (%)
Parent gender
Female 133 (59%)
Male 92 (41%)
Other children than the deceased child 201 (90%)
Not stated 1
Religious 90 (40%)
Not religious 131 (58%)
Marital status
Married/cohabiting 206 (91%)
Single 17 (8%)
Not stated 2 (1%)
Level of education
Primary/secondary school 117 (52%)
University 107 (48%)
Not stated 1
Residential region
Rural 96 (43%)
Town 71 (32%)
City 55 (24%)
Not stated 2 (1%)
Employment
Employed/studying 196 (87%)
On sick/parental leave/unemployed 28 (12%)
Not stated 1 (0.4%)
Characteristics of the deceased children n (%)
Child gender
Girl 66 (44%)
Boy 85 (56%)
Diagnoses
Brain tumors 56 (37%)
Leukemia/lymphoma 42 (28%)
Sarcoma 22 (14%)
Other 32 (21%)
Child age at diagnosis 7.25 (5.32) 0‐16
Child age at death 9.93 (6.54) 0‐24
POHLKAMP ET AL.3
characteristics in Table 1, no statistical differences were found except
for statistical differences in age and employment; fathers were older
than the mothers, t(230) = 2.05, P< .05, and fathers were in employ-
ment more than mothers, χ
2
= (1, N = 224) 9.49, P< .01, as more
mothers were on parental leave. The mean age of the deceased chil-
dren (n = 151) was 7.3 years at diagnosis and 9.9 years at death.
3.2 |Symptoms of prolonged grief, depression,
posttraumatic stress, and insomnia
All mean scores in the total sample as well as for mothers and fathers
separately are summarized in Table 2 and for subsamples by year in
Table 3. Figure 1 illustrates symptom levels for mothers and fathers
in subsamples. Parents' average score for prolonged grief was 29.7
with 32.9% (n = 74) of parents scoring over the cut‐off indicating pos-
sible PGD. Parents' average score on depression was 12.9, indicating
mild depression. The average score for posttraumatic stress symptoms
was 21.3, indicating moderate symptom levels. Parents reported an
average insomnia score of 10.1, which is over cut‐off. Table 2 presents
the scores for symptoms of PGD, depression, posttraumatic stress,
and insomnia, subdivided according to number of years since loss.
3.3 |Differences in psychological symptom levels
across years since loss and between mothers and
fathers
The two‐way ANOVA revealed no statistically significant main effect
of years since loss on symptoms of PGD, F
4
= 0.74, .57. Mothers
had significantly higher PGD symptom levels than fathers, F
1
=
6.22, .01. However, there was no interaction effect between years
since loss and gender on PGD, F
4
= 0.98, .42.
We found no significant main effect of years since loss on symp-
toms of depression, F
4
= 0.27, .90. There was, however, a significant
effect for gender on symptoms of depression, F
1
= 4.06, .05, with
mothers scoring higher than fathers. There was no sign of significant
interaction between years since loss and the parents' gender on
depression, F
4
= 1.17, .32.
No significant difference was observed in posttraumatic stress
symptoms across years since loss, F
4
= 0.49, .75. Mothers scored sig-
nificantly higher on posttraumatic stress symptoms than fathers, F
1
=
5.24, .02. There was no significant interaction between years since
loss and gender on posttraumatic stress symptoms F
4
= 1.60, .17.
In symptoms of insomnia, we saw no significant effect of years
since loss, F
4
= 1.12, .35 and no difference between genders, F
1
=
1.92, .17. There was no significant interaction between years since
loss and gender on insomnia F
4
= 1.16, .33.
Symptom levels of mothers and fathers in the subsamples
corresponding to years since loss are illustrated in Figure 1. Overall,
symptom levels are elevated for all subsamples. Even though we
found no significant interaction effect between years since loss and
gender on the bereavement outcomes, the graphs show a pattern of
mothers reporting more intense reactions than fathers in years 1 to
3, while the intensity of mothers' and fathers' in grief and psychologi-
cal reactions are more similar in years 4 and 5. However, for insomnia,
the pattern is somewhat different.
4|DISCUSSION
This study examined bereavement outcomes and psychological symp-
toms in a Swedish sample of 232 parents who had lost a child to can-
cer 1 to 5 years earlier. Parents reported elevated levels of prolonged
grief, depression, posttraumatic stress, and insomnia across the first 5
years postloss. Mothers reported higher symptom levels of prolonged
grief, depression, and posttraumatic stress than fathers, but no differ-
ences between mothers and fathers were found regarding insomnia.
When splitting the total sample into subsamples according to years
since loss, there was no significant interaction effect between years
since loss and gender on the symptom levels of prolonged grief,
depression, posttraumatic stress, and insomnia.
This study showed that adjustment to a loss for parents takes at
least 5 years, since all the subsamples divided by years since loss
showed similar symptom levels. Even though the present study is
TABLE 2 Self‐reported mean symptom levels in bereaved parents
All Parents Mothers Fathers
Mean (SD) Mean (SD) Mean (SD)
Prolonged grief 29.70 (SD 9.54) 31.01 (10.11) 27.80 (8.34)
Depression 12.91 (SD 9.30) 13.89 (9.64) 11.36 (8.59)
Posttraumatic stress 21.34 (SD 15.94) 23.40 (16.59) 18.24 (14.58)
Insomnia 10.12 (SD 7.46) 10.70 (7.63) 9.11 (7.06)
TABLE 3 Self‐reported symptom levels in bereaved parents; subsamples by years since loss
Years since loss
Prolonged grief Depression Posttraumatic Stress Insomnia
Mean (SD; n) Mean (SD; n) Mean (SD; n) Mean (SD; n)
N = 225 N = 225 N = 222 N = 222
1 30.47 (9.59; 45) 12.22 (9.00; 45) 19.33 (14.21; 44) 9.56 (7.23; 43)
2 31.26 (10.28; 43) 13.86 (10.49; 42) 23.36 (18.20; 43) 9.59 (7.80; 42)
3 29.56 (9.52; 45) 12.84 (10.17; 45) 20.26 (15.27; 43) 8.98 (6.35; 45)
4 29.14 (9.64; 37) 13.79 (8.97; 38) 22.48 (16.08; 37) 11.92 (8.85; 39)
5 28.35 (8.95; 55) 12.20 (8.23; 55) 21.44 (16.11; 55) 10.65 (7.10; 53)
4POHLKAMP ET AL.
not longitudinal, a pattern was observed where mothers showed
higher symptom levels and fathers showed lower symptom levels at
1‐year postloss. However, at 5 years postloss, fathers' symptoms,
which had been lower at year 1, were the same or even higher than
mothers in later years. Similarly, Ljungman et al
11
found that cancer‐
bereaved mothers reported initially higher symptom levels of post-
traumatic stress, which declined from 9 months to 5 years postloss;
fathers' posttraumatic stress symptoms were initially lower than
mothers' but had a weaker decline, and at 5 years postloss, mothers
and fathers had similar symptom levels. A recent review on parental
grief concluded that the grief experiences after the loss of a child
are generally so long lasting and severe that they might warrant paren-
tal grief being considered a distinct subtype of grief.
1
In the present study, both mothers and fathers report values near
or over the cut‐off for insomnia symptoms. There is growing evidence
for sleep disturbance being associated with mental health symptoms
following loss,
28
which is consistent with research in other populations
showing that long lasting sleep disturbance is related to poor psycho-
logical and physical health.
17
This indicates that parents may also suf-
fer from multiple psychological or physiological symptoms that are
associated with insomnia.
On a group level, mothers in this study reported more symptoms
than fathers. This is consistent with several studies showing a higher
risk for mothers than fathers regarding psychological ill health after
the loss of a child. For example, bereaved mothers are reported to
show more intense grief reactions,
29,30
more symptoms of depres-
sion,
31
and more posttraumatic stress symptoms
32
than fathers. Possi-
ble theoretical explanations for differences between mothers' and
fathers' grief reactions may be found in the dual process model of
coping with bereavement. To undertake the process of adjustment,
oscillating between two types of coping is needed.
21
While women
tend to use loss‐oriented coping, focusing on their grief and express-
ing emotions, men often prefer more externally oriented coping,
engaging in practical tasks; this may reflect cultural and societal habits
regarding behavior and emotional reactions in both genders.
33
How individuals adjust to bereavement is predicted by various fac-
tors,
34
but the grief experienced by parents is generally very severe,
35
probably reflecting the strong attachment relationship between par-
ents and children. Parents with severely ill children often develop
strong relationships with health care staff whom they come to rely
on in a distressed situation. The need of the parents for continued
connection with health care staff and hospital community, thus offer-
ing them access to available attachment figures, may be considered
when developing interventions aimed at improving parents' psycho-
logical bereavement outcomes. Standardized follow‐ups of the parents
will enable identification of those at risk for psychological symptoms
and offer them targeted support if needed.
6
The results of this study
indicate that bereaved parents may need access to support up to 5
years postloss.
Lichtenthal et al
36
showed that many cancer‐bereaved parents do
not receive bereavement support, partly because the loss is not only
too painful to talk about but also due to difficulties in finding such ser-
vices. Currently, childhood cancer centers often lack routines for
assessment of the parents' needs of bereavement care, prior to and
postloss, and even if such services are available, there are large varia-
tions in how they are delivered.
37
The other recommended standard is
community‐based resources as a sustainable framework for bereave-
ment care, but the availability and quality of such support are highly
variable.
38
Therefore, standardized bereavement support is suggested
to be included as an integral part of pediatric care settings. Therapeu-
tic alliances between parents and health care professionals are already
established during the child's illness, which may help facilitate the
FIGURE 1 Symptom levels for mothers and
fathers in subsamples by years since loss. The
maximum numbers on the y‐axes reflect the
specific score range of each instrument
POHLKAMP ET AL.5
adjustment and the healing of the parents following the loss of their
child.
39
Clearly, grief after the loss of a child deserves attention in its
own right, both in future research and in the development of bereave-
ment care.
4.1 |Study limitations
This is the first study to examine both prolonged grief, depression,
posttraumatic stress, and insomnia by means of validated instruments
in a total population of parents in Sweden who had lost a child to can-
cer 1 to 5 years previously. Other strengths include the equal gender
distribution among responders and the small number of missing
responses in the questionnaire. One limitation is that the unavailability
of data on the psychological health of nonresponders, which limits the
generalizability of the results. Since the results of this study are based
on a Swedish nationwide population, we can speculate that our results
could be valid for all parents in Sweden who have lost a child to
cancer. Because of cultural differences in grief and bereavement care,
we cannot be certain that our results would be generalizable to other
cultural contexts or other causes of death. Another limitation is that
the results are based on self‐reported data, and no clinical assessment
interviews were conducted.
4.2 |Clinical implications and conclusions
The death of a child has long‐lasting effects on the psychological
health of the parents. Cancer‐bereaved mothers and fathers are vul-
nerable to prolonged grief, depression, posttraumatic stress symp-
toms, and sleep disturbances up to 5 years after the death of their
child. Mothers showed higher symptom levels of prolonged grief,
depression, and posttraumatic stress than fathers. However, we found
no interaction effect of time and gender on parents' grief over the first
5 years following loss. Since the results indicate that some cancer‐
bereaved parents may suffer from prolonged grief and psychological
symptoms at least up to 5 years after the death of their child, clinicians
should be aware of this when meeting bereaved parents. This is a
much longer timespan than is current practice for bereavement care
in most pediatric oncology settings. The long‐lasting psychological
problems reported by the parents in the present study underscore
the need to establish policy guidelines for provision of psychological
support to cancer‐bereaved parents, who may need support even
years after a child's death.
ACKNOWLEDGEMENTS
We thank the parents who participated in the study. This study was
financially supported by the Swedish Childhood Cancer Foundation,
Gålö Foundation, and Ersta Sköndal Bräcke University College.
CONFLICTS OF INTEREST
None declared.
ETHICAL STANDARDS
The authors assert that all procedures contributing to this work
comply with the ethical standards of the relevant national and institu-
tional committees and with the Helsinki Declaration of 1975, as
revised in 2008.
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available on
request from the corresponding author. The data are not publicly
available due to privacy or ethical restrictions.
ORCID
Lilian Pohlkamp https://orcid.org/0000-0002-4142-5967
Josefin Sveen https://orcid.org/0000-0002-5523-8126
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How to cite this article: Pohlkamp L, Kreicbergs U, Sveen J.
Bereaved mothers' and fathers' prolonged grief and psycholog-
ical health 1 to 5 years after loss—A nationwide study. Psycho‐
Oncology. 2019;1–7. https://doi.org/10.1002/pon.5112
POHLKAMP ET AL.7
