Eating behaviors of Women with an Eating Disorder and Autism Spectrum Disorder

Eating disorders (ED) are serious and often fatal illnesses that are associated
with severe disturbances to a person's eating behavior and related thoughts and
emotions, accompanied by a preoccupation with food, body weight and shape
(American Psychiatric Association, 2013). While EDs do not discriminate between
gender, age and ethnicities (Marques et al., 2011), most sufferers are women
(Keski-Rahkonen & Mustelin, 2016). Reports of lifetime prevalence rates of EDs
range between 1 and 8.4% (Galmiche et al., 2019; Keski-Rahkonen & Mustelin,
2016), with anorexia nervosa (AN) being associated with the highest mortality
rate among all mental disorders (Smink, van Hoeken & Hoek, 2012).
Among other personal and behavioral issues, a substantial amount of people with
EDs display difficulties with rigidity (Danner et al., 2012; Dingemans et al.,
2015; Aloi et al., 2015) and social impairments (Mandy & Tchanturia, 2015).
These issues often go hand in hand with other psychiatric comorbidities that
are thought to hamper treatment and subsequently impede recovery (Keshishian et
al., 2019; Franko et al., 2018; Welch et al., 2016; Keski-Rahkonen & Mustelin,
2016). One of these comorbidities is autism spectrum disorder (ASD). Based on
the apparent symptomatic overlap between these disorders that has been found on
neurocognitive, behavioural and personal levels, a large body of literature has
recently focused on the role and clinical implications of ASD and ASD traits
that are repeatedly found in ED samples (Dell*Osso et al., 2018; Huke et al.,
2013; Karjalainen et al., 2019; Nickel et al., 2019; Westwood & Tchanturia,
2017). Problems with communication (Treasure, 2013), cognitive rigidity (Danner
et al., 2012; Aloi et al., 2015), restrictive and repetitive behaviours
(Treasure, 2012) and perfectionism (Treasure, 2013) been reported as
commonalities, as well as social impairments such loneliness, isolation and
shyness (Krug et al., 2013; Fairburn, Cooper, Doll & Welch, 1999).
Reported prevalence rates of ASD and ASD traits in ED samples vary between 4%
and 52.5% (Nickel et al., 2019; Dell*Osso et al., 2018; Westwood & Tchanturia,
2017; Huke et al., 2013), suggesting an overrepresentation of ASD and ASD
traits in ED samples. This broad range of reported ASD and ASD traits can be
attributed partly to the use of various diagnostic measures that handle diverse
criteria and thresholds: With ASD officially being a pervasive
neurodevelopmental disorder, one of its criteria is the onset of ASD traits to
be during the early developmental period (American Psychiatric Association,
2013). Studies using parental reports to determine the presence of these traits
during that time, often report much lower rates (Westwood, Mandy, Simic &
Tchanturia, 2018; Rhind, Bonfioli, Hibbs, Goddard & Macdondald, 2014; Pooni,
Ninteman, Bryant, Nicholls & Mandy, 2012). On the other hand, studies that used
self-report measures like the Autism Spectrum Quotient (Baron-Cohen et al.,
2001) or semi-structured assessments like the Autism Diagnostic Observation
Schedule (Lord et al., 2012) to observe characteristics associated with ASD, do
not handle this criterium and often report higher rates of ASD traits. Another
issue in the investigation of ASD and ASD traits in ED populations is that ASD
often presents itself often differently in women compared to men on various
cognitive-behavioural domains (Hull et al., 2017; Lai et al., 2015; Lai &
Baron-Cohen, 2015): Women with autism are thought to have a stronger use of
strategies to compensate for and mask autistic characteristics during social
interaction called camouflaging (Hull et al., 2019), less restrictive and
repetitive behaviors (Lai et al., 2015; Supekar & Menon, 2015) and different
special interests (Halladay, Bishop & Constantino, 2015). In the past,
diagnostic assessments such the DSM-5 criteria or the ADOS-2 have been
validated with males ((Westwood & Tchanturia, 2017), not taking gender
differences into account. This oftentimes resulted in females being not at all
or diagnosed much later than men (Rynkiewicz et al., 2016). This difficulty has
recently led to the investigation of the female ASD phenotype and subsequently
to the development of diagnostic instruments that specifically take
characteristics of the female autism phenotype into account (e.g. M-ASD;
Bezemer & Blijd-Hoogewys, 2016). With ED populations reporting a much bigger
female to male ratio compared to gender ratios in ASD where there are 3,5 males
for every female (Loomes et al., 2017), assessing ASD and ASD traits in ED
populations therefore poses an extra difficult task. In light of these
obstacles regarding the assessment of ASD traits in ED populations, the
discussion remains whether these found traits were already premorbidly present
to the start of the ED, possibly even playing a role in the development of the
ED (Gillberg, 1985; Tchanturia et al., 2004), or whether they are a consequence
of the EDs themselves, for example through starvation effects in anorexia
nervosa (Keys et al., 1950; Oldershaw et al., 2011).
But regardless of whether these traits are epiphenomena of the ED
itself or are indications of an ASD existing next to the ED, the presence of
them has serious clinical implications for patients. Although there is still a
lack of research in this area, elevated ASD traits have been associated with a
more severe presentation of the ED and subsequently with poorer treatment
outcome (Kinnaird et al., 2017, 2019; Nielsen et al., 2015), often requiring an
augmentation of standard treatments (Stewart et al., 2017; Tchanturia et al.,
2016). A qualitative study by Kinnard et al. (2019) suggests that women with an
ED and elevated ASD traits might have unique needs that relate to their
autistic traits and require an adaptation to treatment. It is possible that the
rigidity and inflexibility associated with their ASD contributes to the
development of their ED, where the need for control, rigid thought patterns and
sensory difficulties play a greater role than body image issues and a desire to
lose weight (Kinnaird et al., 2019). When treatments are thus aimed at changing
apparent ED behaviours that are in fact related to their autism, recovery can
stagnate (Kinnaird et al., 2019). A way to tackle this is to gain more
knowledge on how the eating patterns and behaviours of women with an ED and
comorbid ASD actually look like and how they compare to women with an ED
without ASD. Little to no research has yet looked into the specific eating
behaviours of ED patients with comorbid ASD. When approaching from a different
angle, there has been some documentation on eating behaviours of children with
ASD, who appear to be five times more likely to have feeding related problems
compared to age-matched controls (Sharp et al., 2013). Their eating behaviours
vary from food selectivity to refusal, food neophobia, sensory sensitivity with
regard to certain foods and problems around meal time behaviours (Postorino et
al., 2015; Sharp et al., 2013), resembling behaviours and attitudes with regard
to food often found in people with avoidant restrictive food intake disorder
(ARFID) (Hay et al., 2017). Regarding eating behaviours of adults with ASD
however, documentation is scarce, as most studies have either focused on
children or on people with intellectual impairment. Spek and colleagues (2019)
recently investigated eating behaviours of men and women with ASD and compared
these to age-matched controls. Their results indicated that men and especially
women with ASD experience significantly more eating problems than controls,
such as having eating rituals, sensory sensitivities, experiencing difficulty
to eat among other people, problems with mealtime surroundings and adapting
their eating behaviour to their social environment. Here, women with ASD also
reported significantly more charac

The goal of this study is to gain insight into the eating behaviors of women
with an eating disorder (ED) and comorbid autism spectrum disorder (ASD). By
comparing this group to two other groups (women with an ED but without ASD and
women with an ASD but without an ED), it will also be investigated if and how
their eating behaviors are differed compared to women with an ED but without
ASD and compared to women with an ASD but without an ED. In addition to that,
we will investigate whether the eating behaviors of women with an ED and
comorbid ASD relate to other general psychiatric complaints and how they relate
to problems with regard to daily and neurocognitive functioning and quality of
life.

Observational cross-sectional study that will involve at least 80 female
participants, 18 years or older: 30 with an ASD, 30 with an ED and at least 20
with an ED and ASD, as this group will be harder to collect, that will be
recruited with the help of clinicians on two different study locations
(Altrecht Eating disorders Rintveld and the Autism Expert Centrum).
Participants will be asked to take part in a one time online assessment
containing various questionnaires about picky eating behavior, ARFID related
eating behaviors, disturbed eating behaviors, ASD specific eating behaviors and
other general psychiatric complaints, problems with daily and neurocognitive
functioning and quality of life.

Participants are asked to take part in a one-time only interview and to fill in
some questionnaires, which will take max. 65 minutes. The burden can therefore
considered to be low and no risks are associated with participation. It is thus
our opinion that benefits of this study outweigh the risks.