High Functioning Autism Spectrum Disorders in Adults: Consequences for Primary Caregivers Compared to Schizophrenia and Depression
Journal of Autism and Developmental Disorders
High Functioning Autism Spectrum Disorders in Adults: Consequences for Primary Caregivers Compared to Schizophrenia and Depression
Inge A. C. Grootscholten 0 1 2
Bob van Wijngaarden 0 1 2
Cornelis C. Kan 0 1 2
Arnhem, The Netherlands
0 Netherlands Institute of Mental Health and Addiction , Da Costakade 45, 3521 VS Utrecht , The Netherlands
1 Department of Psychiatry, Radboud University Medical Center , Nijmegen, Reinier Postlaan 4, 6525 EX Nijmegen , The Netherlands
2 Dr. B. van Wijngaarden is retired from the Netherlands Institute of Mental Health and Addiction , Utrecht , the Netherlands
Primary caregivers experience consequences from being in close contact to a person with autism spectrum disorder (ASD). This study used the Involvement Evaluation Questionnaire to explore the level of consequences of 104 caregivers involved with adults with High Functioning ASD (HF-ASD) and compared these with the consequences reported by caregivers of patients suffering from depression and schizophrenia. Caregivers involved with adults with an HF-ASD experience overall consequences comparable to those involved with patients with depression or schizophrenia. Worrying was the most reported consequence. More tension was experienced by the caregivers of ASD patients, especially by spouses. More care and attention for spouses of adults with an HF-ASD appears to be needed.
Autism spectrum disorders; High functioning; Caregiver consequences; Parents; Spouses
It has been recognized since the 1950s that a psychiatric
disorder can have a major impact on the significant
others (SO: parents, spouses, siblings, friends) of the patient
(e.g. Schene 1990; Baronet 1999; Cuijpers and Stam 2000;
Wittmund et al. 2002; Ostman et al. 2005; Gelkopf and Roe
. Most studies in the area of family caregiving have
been conducted on SO concerned with patients with physical
(e.g. Geurtsen et al. 2010) or mental disabilities
Murphy et al. 2007)
, dementia (e.g. Barusch and Spaid 1989)
or psychiatric disorders such as schizophrenia or affective
Grootscholten currently works as a psychiatrist at Max Ernst GGZ
in Arnhem, the Netherlands.
(e.g. Goossens et al. 2008; van Wijngaarden et al.
2009; Granek et al. 2016; Kumar et al. 2015)
Autism spectrum disorders (ASD) are developmental
disorders characterized by an impairment of reciprocal
communication and social interactions and the presence of restricted
stereotypical behaviors and interests
What is known about the impact of ASD on their SOs?
Literature published on the impact of ASD on primary
caregivers mainly focuses on the consequences for parents
(mostly mothers) with an autistic child that often has a
concomitant intellectual disability as well as a language disorder
(e.g. Milgram and Atzil 1988; Hartley et al. 2011; Hayes and
Watson 2013; Burke and Heller 2016; Tomeny 2016)
parents experience a profound number of consequences such
as high levels of parenting stress
(Lecavalier et al. 2006;
Milgram and Atzil 1988)
or feelings of guilt and failure
Tongerloo et al. 2015)
. These levels of consequences are
high compared to parents of children with a normal
development, but also high compared to parents with a child with
another disability such as Down syndrome, cerebral palsy,
fragile X or Fetal Alcohol Spectrum Disorder
. As a result of these chronic high levels of
parenting stress these parents report an increase of mental
health problems such as the risk of developing a
(e.g. Tomeny 2016; Lin 2011; Lecavalier et al.
2006; Orsmond et al. 2007)
Tint and Weiss (2016)
Karst and Van Hecke (2012) for a recent review.
In the 1970s and 1980s it was thought that > 75% of ASD
patients has an intellectual disability
(Schalock et al. 2007)
In more recent years, partly due to the changed perspective on
autism as a spectrum disorder, more attention has been paid
to those with ASD without an intellectual disability, called
High Functioning ASD (HF-ASD). They have an average to
above average intelligence (IQ > 70) and are often considered
as having a ‘milder type’ of ASD
Rao and Beidel (2009)
have studied the impact on
parents of children with HF-ASD, and concluded that in case
of HF-ASD the levels of parenting stress, the restriction of
family functioning, and the risk of psychological problems
and poorer mental and physical health are higher compared
to families with children without a psychiatric disorder. The
higher intellectual functioning of the children did not
ameliorate the high levels of stress in their parents. They also
described that children with HF-ASD had less
externalizing (behavioral) problems, but higher levels of internalizing
problems, such as depression and anxiety, which would also
contribute to the parental stress.
HF-ASD patients can often go unrecognized until well
into adolescence or adulthood, possibly because they are
able (at least to some extent) to compensate for social
clumsiness by copying the behavior of their peers and because
they are protected by structure and support from SO. But
when changing circumstances (such as going to college,
finding a job or becoming intimately involved) demand
skills which exceed their abilities, they become aware of
their inadequate coping and their deficits in social
(Marriage et al. 2009; Lehnhardt et al. 2013)
What Do We Know About Adults with HFA‑SD and the Impact on Their SO?
When focusing on adults with ASD, most literature is
concerned with the problems of transition of the autistic child
to adolescence and adulthood, difficulties with the
different healthcare services organized for children and adults,
and how this impacts the parents who continue to parent
longer than parents with children without ASD
et al. 2012; Smith et al. 2012; Weiss et al. 2016; Hartley and
Schultz 2015; Burke and Heller 2016)
, but these adults often
had intellectual disabilities as well. Cadman et al. (2012)
concluded that adolescence and young adulthood are
associated with high levels of caregiver burden, that this burden
was greater in ASD compared to
attention-deficit/hyperactivity disorder and that this was mainly explained by the
patient’s unmet needs.
Renty and Roeyers (2007)
studied the marital satisfaction
of 21 couples consisting of a HF-ASD male and a non-ASD
female. They found that women whose husband showed less
autism-specific traits reported higher levels of marital
satisfaction. They also found that the marital adaptation in the men
was significantly associated with more received and perceived
social support from the spouse and from family and friends.
Lau and Peterson (2011)
studied the attachment styles of 22
adults with HF-ASD (7 males, 15 females) and found that
73% of them had an avoidant style of attachment, as opposed
to the secured romantic attachment style found in 72%
nonASD spouses. Spouses of HF-ASD showed less marital
satisfaction, but this could be explained by the presence of an
ASD-child. They concluded that the husband’s or wife’s ASD
status had little impact upon any aspect of marital quality.
In our clinical practice with adult patients newly
diagnosed with HF-ASD we encounter primary caregivers who
report a significant impact on their daily lives, relationships
and family life. In order to assess the magnitude of this
impact on the SO, we have acquired self-report data on the
level of consequences and general aspects of their health in
a sample of SO of adult HF-ASD patients, and have
compared these data to data of samples of SO of patients with
depression or schizophrenia. The reason we have compared
our data to these two groups is because schizophrenia and
major depressive disorders are both, although different in
nature, considered as serious psychiatric disorders. HF-ASD
is considered by some as a milder form of ASD, so it would
be interesting to compare the consequences of HF-ASD for
SO to these serious disorders.
For this study we hypothesized the following:
(1) The impact on SO of adults with HF-ASD is
comparable to the impact on SO of patients with depression or
(2) More symptoms of ASD recognized by the SO
correlate with a higher level of consequences reported by
(3) The impact on parents or spouses will be different
(4) As in the case of schizophrenia and depression, SO who
experience consequences of the disorder of their child/
partner/family member will be at risk of developing
(mental) health problems themselves
Inclusion Criteria and Patient Samples
Data on the consequences of depression or schizophrenia
on caregivers originate from the research done by van
Wijngaarden et al. (2009). The depression sample consisted of
relatives, friends, partners or other caregivers of patients
who suffered from depression (major depressive
disorder, dysthymic disorder, other depressive disorders). The
patients were all treated in a mental hospital specialized in
the treatment of depression in the Netherlands. Patients were
asked for written permission to contact a SO and to send
them a questionnaire by mail. From this data we used the
outpatient data only (N = 237), to match our population.
The schizophrenia sample originated from the European
(Becker et al. 2000)
, which identified a
representative cohort of patients with schizophrenia. From this
sample we used the outpatient data from the Northern
European countries: the Netherlands, Denmark and the United
Kingdom (N = 150). For more details see van Wijngaarden
et al. (2009).
The ASD data were collected at the outpatient clinic of
the Radboud University Medical Center in Nijmegen, the
Netherlands. This clinic has a special outpatient program for
adults suffering from developmental disorders (ASD and/
Adults referred to this department experience, for
example, problems with social interaction, non-verbal
communication, and/or restricted patterns of behavior and interests.
These may cause problems in intimate and professional
relationships, often resulting in social isolation, conflicts at
work or within the family unit. The majority of these adults
has not been diagnosed with an ASD during childhood due
to their compensating normal to high intelligence (IQ > 70).
Patients who have been diagnosed with ASD were offered
to participate in a psycho-educational group course. In this
course information about ASD was given, and the impact
of different aspects of ASD on an individual’s life was
Every participant of the psycho-educational course had to
bring a SO. This SO could be a spouse, a parent, a sibling, a
friend, or a professional caregiver. At the Radboud Medical
Center it is considered important that the information given
in the psycho-educational course does not only reach the
patient, but his/her surroundings as well. Someone who is
close to the patient can be extremely helpful to the patient
in recognizing the specifics of ASD in his/her own life, and
can contribute to the generalization of the knowledge about
ASD to everyday life beyond the group meetings.
Reasons for exclusion from the psycho-educational
course were: intellectual disability (IQ < 70), concurrent
psychosis, or a personality disorder of such an extent that it
would interfere strongly with participation in a group with
other patients. Patients who were excluded received
SO of ASD patients were asked to complete a number of
questionnaires, including the Involvement Evaluation
Questionnaire (IEQ), General Health Questionnaire (GHQ-12),
and Autism-Spectrum Quotient (AQ), before the start of the
psycho-educational course. Informed consent was signed by
all the participants for use of data for research.
The Medical Ethics Committee of the Radboud
University Medical Centre stated that no ethical approval was
needed because of the non-invasive character of the
The IEQ is an internationally validated self-rating
questionnaire which measures consequences experienced by those
involved with people with psychiatric illnesses
Wijngaarden et al. 2000, 2004, 2009; Martin et al. 2015; Cuijpers
and Stam 2000)
. The IEQ-scores correlate to patients’
characteristics, and predict caregiver distress as assessed with
(Goossens et al. 2008; Goncalves-Pereira et al.
. IEQ-scores assess various aspects of caregiving
consequences such as the encouragement, supervision and care
the caregiver has to provide to the patient, strain experienced
on the relationship due to interpersonal problems between
patient and caregiver, and to the caregiver’s worries. The
core module measuring the ‘caregiving consequences’
comprises 31 items, which focus on the objective aspects
of the caregiver’s experience, scored on 5-point Likert
scales (0 = never, 1 = sometimes, 2 = regularly, 3 = often and
4 = always). The questionnaire is divided into four subscales:
Tension, referring to a potentially strained interpersonal
atmosphere between the patient and the SO; Supervision,
which, amongst others, refers to the SO’s task of keeping the
patient from committing dangerous acts, or the supervision
of taking medication; Worrying refers to worrying about
the patient’s health, safety and future, and Urging refers to
the motivation and activation of the patient. The time-frame
is the 4 weeks prior to the assessment. The IEQ has shown
extensive reliability and internal consistency, in the
Netherlands as well as internationally
(Schene 1990; Becker et al.
1999, 2000; van Wijngaarden et al. 2000; Magne-Ingvar and
Ojehagen 2005; Goossens et al. 2008; Geurtsen et al. 2010)
It can be administered to any caregiver, including friends
and neighbors, who are in contact with the patient for at
least 1 h/week.
The GHQ-12 is a well-validated self-administered
instrument for the detection and measurement of
psychopathology in the community
(Goldberg et al. 1997; Goldberg and
. It consists of 12 questions referring to
subjects such as lack of sleep, loss of confidence, and feeling
depressed. It is used to identify general emotional distress
and possible health risks for the caregiver. Higher GHQ
scores represent higher levels of distress. Possible answers
are: ‘better than usual’, ‘as good as usual’, ‘worse than
usual’, and ‘much worse than usual’ for positively phrased
questions, and ‘not at all’, ‘same as usual’, ‘rather more
than usual’, and ‘much more than usual’ for the negatively
The AQ was used to capture the severity of ASD
symptoms. The AQ was developed by Baron-Cohen et al.
BaronCohen et al. 2001
) and measures the amount of autistic traits
in adults of normal intelligence. It has been broadly tested
and widely used to differ between ASD and non-ASD
caseness in the process of patient evaluation. The 50 item
selfreport questionnaire includes five domains: Social skill,
Attention switching, Attention to detail, Communication,
and Imagination. We used the ‘parent report version’; this
can be completed by a parent or other primary caregivers
(Baron-Cohen et al. 2006)
The Dutch AQ has shown good sensitivity and specificity
(Hoekstra et al. 2008)
In order to study the differences in IEQ subscale scores
between the depression, schizophrenia and ASD samples,
so-called ‘consequences indices’ (C-indices) were
computed, as described by van Wijngaarden et al. (2009). IEQ
item scores of ‘0’ or ‘1’ (never, sometimes) are considered
as indicating ‘no real consequence’. Item scores of ‘2’ or
higher (regularly, often or always) are considered as
indicating a ‘real consequence’. The number of ‘real consequences’
are computed and divided by the total number of items in the
scale. Four subscale C-indices and one overall C-index (total
score), all ranging from ‘0’ (no consequences at all) to ‘1’
(maximum level of consequences) were computed this way.
There are three different ways of scoring the GHQ-12:
the binary (0,0,1,1), chronic (0,1,1,1) and Likert scoring
(Goldberg et al. 1997)
. The Likert scoring gives
a wider and steadier score distribution to assess severity
and can be used for correlation analysis. The Likert scoring
was therefore used in this study. The possible score ranges
from 0 to 36, with higher scores representing higher levels
of distress. Threshold for caseness varies in different
(Goldberg et al. 1998)
. As no threshold was
published for the Dutch population, the threshold for the
German population as published by
Schmitz et al. (1999
was used (11/12). We expected Germany, being a
neighboring country of the Netherlands with approximately the same
socio-economic situation and organization of health care, to
be the best comparable country available.
There are two ways of scoring the AQ: a 4-point Likert
score or a binary one in which answers ‘definitely agree’
and ‘agree’ score as 1 on autism positive traits and
‘definitely disagree’ and ‘disagree’ score as 1 on autism
negative traits. The binary score is proposed by Baron-Cohen
and is used in this research. It has a minimum of 0 and a
maximum score of 50, the higher indicating more
autistic traits. The cut-off for caseness was 32 as proposed by
Baron-Cohen et al. (2001
The statistical calculations were made using the IBM
Statistical Package for the Social Sciences version 22.0.
Comparisons between IEQ C-indices scores for the different
disorders and SO-groups were made by the
Kruskal–Wallis test for non-parametrically distributed, independent
samples as advised by
. Comparison between
GHQ scores were made by the Mann–Whitney test. All
effects are reported at a significance level of p< .05, unless
stated differently. Effect sizes were computed using
Pearsons’ r. Correlation of IEQ with GHQ scores and of IEQ
with AQ scores were calculated using the Spearman rank
correlation coefficient (two-tailed) for non-parametrically
distributed variables. Two-tailed ANOVA was used to
compare AQ data in the SO-groups. We did not control
for any demographic factors throughout the analysis.
Between 2006 and 2009 approximately 660 patients were
referred to the outpatient clinic for diagnostic assessment
of ASD. 38.5% of these 660 patients was not diagnosed
with an ASD, 17% was classified with autistic disorder,
19% with Asperger’s disorder, and 21% with PDD-NOS
by use of Diagnostic and Statistical Manual of Mental
Disorders (DSM-IV TR)
. 1.5% of the referred patients did not finish the
course of examination. No files were found in the archives
with respect to 3% of the patients.
129 of the 376 patients diagnosed with ASD enrolled in
the psycho-educational group course. There were several
reasons, apart from not meeting the inclusion criteria, for
patients not to participate in the psycho-educational group,
ranging from unwillingness to participate in a group or
living too far away from the center, to having the
opinion that a psycho-educational group could do nothing to
alleviate his/her problems. Bi-nominal regression analysis
showed that there was no selection bias, based on
subclassification according to DSM-IV, and age or gender of
Of the 129 SO who joined a patient in the
psycho-educational group course between 2006 and 2009, 110 handed in
the questionnaires. Due to missing data, questionnaires of
104 SO could be used for analysis.
gender distribution of the disorder: ASD is diagnosed at
least three times as often in males as in females
et al. 2004; Loomes et al. 2017)
Our sample was too small to perform a reliable
confirmatory factor analysis. In order to get some idea of the validity
of the IEQ for an ASD sample, a preliminary exploratory
factor analysis was conducted. It showed a slightly different
factor structure compared to the standard IEQ structure. We
found four subscales, which consisted of Tension,
Worrying, Urging and Supervision combined together, and a fourth
mixed scale. Tension showed to be the most robust factor.
Five items referring to Supervision and Urging were not
included in one of the factors.
In order to test the reliability of the IEQ in the
ASD-population, Crohnbach’s alpha was computed, using the
standard IEQ scales. These were acceptable for the total score
(0.8), the subscale Tension (0.8), subscale Worrying (0.7)
and subscale Urging (0.7). Subscale Supervision, however,
had an alpha of 0.3. Because this subscale is not reliable in
our sample it was not used in the comparison analysis.
significant. SO of ASD patients experienced significantly
more emotional distress compared to SO of schizophrenic
patients [U = 9130.00, p = .006, r = 0.18]. Also, there was a
significant positive correlation between the IEQ (subscales
and overall-score) and the GHQ-12 scores, meaning that
higher levels of consequences are correlated with more
distress. No GHQ-12 data were available for the
Looking Closer at Caregivers Confronted with ASD:
In Table 4 the mean C-indices of the IEQ scales for the
different groups of SO connected to a patient with ASD are
presented. Significant differences between the groups of
primary caregivers were found on all three subscales and
on the total consequences score. Differences were greatest
on subscale Tension [H(2) = 20.98 p < .000]. Pairwise
comparison showed that spouses scored significantly higher than
both parents (p adj = .008 r = 0.31) and others (p adj < .000
r = 0.48).
Mean C-index (SD)
Mean C-index (SD)
Mean C-index (SD)
Caregiver consequences in the depression, schizophrenia
and ASD sample were compared using the total score and
the subscales Tension, Worrying, and Urging. In Table 2
the mean C-indices of the IEQ scales for the three
samples are presented. No difference was found for the total
consequences. On the subscale of Tension, however, there
was a significant difference between the three samples
[H(2) = 19.76 p < .000]. Pair-wise comparison showed that
Tension was reported significantly more often by the SO of
ASD, compared to the schizophrenia (effect size r= 0.28)
and depression sample (r = 0.17).
A score above threshold (11) indicates psychiatric
morbidity or severe emotional distress. The mean score on
the GHQ-12 was 12.56 for the SO in the schizophrenia
sample, and 14.56 for the SO in the ASD sample, which
where both clearly above the threshold (Table 3). In fact,
49% of the SO of schizophrenia and 62% of SO of ASD
patients scored above the threshold of 11 and were
therefore at risk of developing health problems themselves.
The differences between the SO in both samples were
ASD Autism Spectrum Disorder, GHQ General Health Questionnaire, IEQ Involvement Evaluation Questionnaire
*Mann Whitney U
**p (2-tailed) < .001 p value and correlation coefficient were calculated using Spearman’s rho
Parents scored higher on subscale Worrying compared
to other caregivers (p adj = .012 r = 0.43), but the
difference between parents and spouses was non-significant.
Parents scored higher on subscale Urging compared
to other caregivers (p adj = .025 r = 0.39), but in this
case also, differences between parents and spouses were
Both parents and spouses scored higher on total
consequences score than other caregivers (parents vs.
others p adj = .039, r = 0.37, spouses vs. others p adj = .017
r = 0.32). Also in this case, parents and spouses did not
Table 4 shows that parents and spouses have higher
GHQ12 scores compared to other caregivers (parents vs.
others p adj = .05, r = 0.36, spouses vs. others p adj = .001
r = 0.40), but the difference between parents and spouses
The mean score on the AQ was 34 (SD = 7), well above the
cut-off for caseness of 32 points (Table 5).
Cronbach’s alpha for the subscales was medium to
acceptable: Social skill: 0.7, Attention switching: 0.6, Attention
to detail: 0.7, Communication: 0.6, Imagination: 0.6. The
Kruskal–Wallis test showed no significant difference in the
AQ score between the different SO groups. There was no
significant correlation between the total amount of autistic
traits recognized by the SO and the consequences assessed
with the IEQ (Table 6).
The aim of this study was to investigate the consequences
experienced by SO of adult HF-ASD patients and to
compare these with the consequences experienced by SO of
patients with depression or schizophrenia. The main
outcome of this study is that the overall consequences
experienced by the SO of adult HF-ASD patients are comparable to
AQ Autism-spectrum Quotient, IEQ Involvement Evaluation Questionnaire
those of patients with depression or schizophrenia. On
Tension they even score significantly higher than SO in the other
two samples. This is an important result, because HF-ASD
in adults is often not recognized or diagnosed, and support
and treatment for ASD patients and their SO have never been
a major focus of attention in mental health. Also, HF-ASD
is sometimes regarded as a milder form of ASD
(BaronCohen 2000). Nonetheless, the consequences, especially
for relationships, can be substantial. This is consistent with
our findings in the GHQ-12 data, which show that primary
caregivers of HF-ASD patients experience profound
emotional distress, and are beyond average at risk of
developing mental health problems themselves. These patients and
their SO have been feeling isolated, neglected and poorly
understood, and have therefore not been receiving the
support they needed.
We found that parents and spouses experience
significantly more consequences than other ASD caregivers. This
can be explained by the more intense and emotional bonding
between a spouse or parent and the patient, the large amount
of time they spend together in a household, and the different
expectations that the caregiver has of their spouse or child,
compared to a more distant relationship. Other researchers
also found that the amount of time spent together/living
together with the patient is an important predicting factor
on experienced consequences
(van Wijngaarden et al. 2009;
Ostman et al. 2005; Martin et al. 2015; Kronenberg et al.
Specifics of ASD as Hypothetic Explanations for the Consequences Found
Because of the high levels of heritability of autistic traits
(Muhle et al. 2004; Hoekstra et al. 2007)
, SO of ASD
patients have a higher risk of having another family
member affected by ASD than the general population
et al. 2012)
. This is recognized as an additional cause of
stress in mothers with multiple children with ASD
et al. 2007; Ekas et al. 2009)
. This may also be the case for
spouses who, besides having a partner with ASD, have one
or more children with ASD or another disability
et al. 2014; Lau and Peterson 2011)
Parents of adults with HF-ASD reported high levels of
worrying. It is known from research concerning parents of
young children that parenting a child with ASD can cause
high levels of parenting stress and is correlated with
depression in mothers, but it was believed that this stress
diminished as the child grew older
(Lounds et al. 2007; Ekas and
Whitman 2010; Hartley et al. 2011)
. Our findings show that
parents continue to worry profoundly about their children
with ASD, even when they have reached adulthood. This is
consistent with the research by Cadman et al. (2012) who
found that caregivers of adolescents and young adults with
ASD had very high levels of burden, a level that was
comparable to caregivers of persons with an acquired brain injury.
Spouses of HF-ASD patients experience more tension
in their relationship with the patient compared to parents.
When a partner becomes a patient, more role-taking
confusion occurs than when the patient is a child. Spouses
sometimes talk about their mentally ill partner in terms of “having
(Wittmund et al. 2002)
. This is confirmed
by Ostman et al. (2005) and
Cuijpers and Stam (2000)
also found that spouses showed increased burden compared
to parents and others.
Based on our clinical experience, the lack of mutual
reciprocal interaction, one of the main disabilities in patients
with HF-ASD, is probably a major additional factor
contributing to the perceived burden of the spouses. Due to the
ability to ‘feel’ and understand the other person’s feelings and
needs, and responding accordingly, reciprocal interaction is
valued by many as essential for a fulfilling intimate
relationship. This requires a certain amount of ‘theory of mind’,
often lacking in patients with ASD
We believe parents are less burdened by this, because of
the difference in expectations that a parent has of a child
compared to the expectations one has of a spouse or partner
(van Tongerloo et al. 2015)
Another explanation for the higher levels of tension
reported by spouses of HF-ASD patients is that of gender:
Wittmund et al. (2002) found that female spouses of
psychiatric patients were at a higher risk of getting depressed
themselves than male spouses. In the ASD-sample, 85% of the
spouses was female (50 women vs. 9 men), which reflects
the gender distribution of ASD
(Loomes et al. 2017)
research is inconclusive in regard to the question whether
gender is associated with the amount of caregiver distress
(Sharma et al. 2016; Baronet 1999)
Assortive mating (non-random partner choice) might
influence the relationship between an HF-ASD patient and
suggested that assortive mating
between two high systemizers (people with a high preference
to lawfulness, predictability and categorizing information)
would lead to more autistic children, but Hoekstra et al.
(2007) found no evidence for assortive mating with respect
to mutual autistic traits. It is unclear to what extent
assortive mating might influence the consequences experienced
by a spouse of an HF-ASD patient. One could suggest that
spouses who have several autistic traits themselves (broad
phenotype) would be less bothered or burdened by the social
handicaps of their autistic partners. On the other hand, when
someone is feeling overwhelmed by an outside world that
they do not completely understand themselves, the strain of
caring for someone with the same problems could be
experienced as burdensome.
Contrary to the assortive mating theory, HF-ASD subjects
might also be attractive to empathic, supporting partners
who feel an urge to care for them, and compensate for
their limitations, or to partners who have been emotionally
neglected in their youths and tend to choose a partner who
repeats this emotional neglecting. However, receiving no
emotional reciprocity in return might drain and strain them
in the long run.
Literature is inconsistent on whether ASD symptom
severity contributes to levels of consequences
(Ricard et al.
1999; Tint and Weiss 2016)
. Mothers often report higher
levels of consequences when children with ASD show more
disruptive behavior or higher ASD symptom severity
and Whitman 2010; Tomeny 2016)
. Also, Renty and
Roeyers (2007) found that spouses of men with ASD reported
higher levels of marital satisfaction when their husbands
showed less autism-specific traits as measured with the AQ.
In our sample, the level of ASD symptoms recognized by
the SO was not correlated to the level of consequences they
experienced. Reliability of the AQ domains in our sample
was comparable to that of Hoekstra et al. (2008).
To our knowledge this is the first time that the caregiver
consequences for those involved with an adult with
HFASD have been examined using the IEQ. Even though most
patients in our clinic had not been diagnosed with ASD
during childhood, the impact of their limitations on their
surroundings was substantial.
Because of the consequences experienced by spouses of
patients with HF-ASD, as found in this study and voiced in
the psycho-education group meetings, we believe that extra
attention is needed for this group. They experience a lot of
interpersonal strain in their relationships and are at risk of
developing mental health problems themselves.
Limitations of This Study
The IEQ has been validated in schizophrenia and depression
samples, and has been used with many different psychiatric
disorders since, but it has not officially been validated yet
with respect to ASD. Cronbach’s alpha was acceptable for
the overall score and for 3 of the 4 sub-scales but not for
the subscale Supervision. Items in this subscale, like “how
often during the past 4 weeks have you guarded your
relative/friend from committing dangerous acts” or “have you
guarded your relative/friend from taking illegal drugs” are
possibly not as applicable to HF-ASD as they are to
depression or schizophrenia. These were also items that could not
be included in one of the factors of the preliminary
exploratory factor analysis, which showed a slightly different factor
structure compared to the standard IEQ structure. Tension
seems to be an issue in ASD, which confirms the results
described in this article.
Even though a Confirmatory Factor Analysis was not
performed due to the small sample size, it is encouraging
to see that the IEQ in ASD seems to have a reasonable
amount of reliability and validity. A larger sample size
is needed for official validation for the IEQ in ASD.
Also, more studies need to be carried out to replicate our
Another limitation concerns the different backgrounds
and characteristics of the samples, which reflect the
different context in which the caregiving takes place, and also
reflects the age and gender difference between the
disorders. The ASD data were collected from SO who joined a
psycho-educational ASD course in a specialized outpatient
clinic. Not all patients diagnosed with ASD participated
in this group, and because of the different reasons for not
participating we cannot say for sure in which direction a
selection bias has influenced our results. However, all data
were from SO who were in close contact with a patient,
and experienced consequences more or less on a daily
ASD patients were diagnosed between 2006 and 2009,
the DSM IV-TR
(American Psychiatric Association 1994)
version was used for classification. As the DSM-IV
subclassifications are no longer applicable in DSM 5
(American Psychiatric Association 2013)
, we have only reported
the frequencies of these sub-classifications and have not
included them in further analyses.
(Buck et al. 2014; Cawthorpe 2017;
De-la-Iglesia and Olivar 2015; Hofvander et al. 2009;
Orinstein et al. 2015; Cadman et al. 2012)
co-morbid psychiatric conditions (e.g. depression) make
life more difficult especially for adults with HF-ASD. This
would probably also be of impact on the SO and of
influence on the consequences they experience. Unfortunately,
no data concerning co-morbid psychiatric disorders are
available for the HF-ASD sample, nor for the depression
and schizophrenia sample.
Acknowledgments Part of the data used in this study was published
earlier in Psychiatry Research and was used with permission of one of
the study authors: Dr. Bob van Wijngaarden, who is second author of
(van Wijngaarden et al. 2009)
Author Contributions IG participated in the study design and data
collection, performed statistical analysis and interpretation of the
data and drafted the manuscript. BvW contributed to the data
collection, performed statistical analysis and interpretation of the data and
helped to draft the manuscript. CK conceived of the study, participated
in the design, collection of data and coordination of the study and
helped to draft the manuscript. All authors read and approved the final
Compliance with Ethical Standards
Conflict of interest The authors declare that they have no conflict of
Informed Consent Informed consent was obtained from all the
individual participants included in the study.
Open Access This article is distributed under the terms of the Creative
Commons Attribution 4.0 International License
(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided 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.
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