Anorexia nervosa is a severe life-threatening eating disorder characterized by individuals
purposefully abstain from eating and exercises for many hours to lose weight because they
believe they are overweight (Abu-Baker & Alshdefat, 2020).
Incidence and Prevalence
Approximately 3.4 million young people throughout the world have anorexia nervosa. In the
United States (US), the prevalence among females is of one out of 200. Anorexia nervosa is
common among young women and adolescents. However, the disorder is increasingly seen
among boys, men, and women older than 40 (Abu-Baker et al., 2020). Anorexia nervosa
peaked from the mid-20th century, and the highest incident is reported among females
between the ages of 12 and 18 years old. People who are considered in the higher
socioeconomic classes have the highest number of anorexia nervosa. It is the third prevalent
chronic disease among adolescents. The prevalence rate is 3% in female adolescents. The
mortality rate linked with anorexia nervosa is higher than any other psychiatric disorder,
which is around 4.0%. The highest causes of death are due to suicide, multisystem organ
complications, and substance abuse (Abu-Baker et al., 2020; Valderas Martinez et al., 2019).
Individuals who are on weight loss and strict diet plan only might not develop anorexia
nervosa (Abu-Baker et al., 2020). However, a small number of people might get to that point
after a long period of being on their plan (Abu-Baker et al., 2020). Research showed moderate
biological vulnerabilities to anorexia nervosa from genetic effects. Genetic effects count for
about 56%, environmental effects 35%, and family environments such as pressuring children
to be at the top of their class or abusive parents account about 5%. Serotonin and neurotrophic
abnormalities have been linked to eating disorders such as anorexia nervosa. Also, individuals
with anorexia nervosa presented with remarkable hyperactivity in the amygdala that led to
negative emotions (Selby & Coniglio, 2020).
Anorexia nervosa patients who lost significant weight eventually end up with left ventricular
atrophy as explained by the left ventricular mass index, and decline in chamber dimensions, as
well as the left ventricle and left atrium (Sachs, Harnke, Mehler, & Krantz, 2016). Because of
these changes and low blood volume in the heart chamber, mitral valve prolapse occurs in
spite of the lack of intrinsic myxomatous valvular degeneration. At the same time, low voltage
of ST depression, falt T-wave, and prolonged QT intervals have been detected in
echocardiographic measurements. However, recent research showed that anorexia nervosa
might not necessarily be connected with prolonged QT intervals. Instead, when providers see
it on an electrocardiogram, it should alarm the provider to investigate for secondary causes
such as differences in electrolytes serum levels such as sodium and magnesium or from
medications that can prolong the QT interval (Sachs, Harnke, Mehler, & Krantz, 2016).
Endocrine and Metabolic
Patients who present with severe starvation and deprivation will have endocrine abnormalities
except for elevated levels of peptide YY (Schorr & Miller, 2017). Commonly, the disorder
causes hypothalamic amenorrhea, reduced gonadotrophin-releasing hormone (GnRH),
luteinizing hormone (LH), low estradiol, and testosterone levels. The resistance of growth
hormone is developed, which leads to an increase in the growth hormone and a decrease in the
systemic insulin-like growth factor 1 (IGF1) levels. The low levels of IGF1 perhaps an
adaptive response to reduce energy on the growth during chronic starvation (Schorr & Miller,
Dieting for an extended period leads to the dysfunction of gastrointestinal organs, which leads
patients to begin complaining of digestive illnesses. Some of these illnesses are fullness after
eating lunch or dinner, constipation, epigastric pain or discomfort, dysphagia, and nausea.
These symptoms may present mildly, but these signs can lead to severe complications, which
may require surgical intervention. Patients will also complain of dry mouth, issues with foul
mouth smell, and decrease in saliva production. Anorexia nervosa patients have much lower
rate of stomach emptying compare to healthy individuals. This condition is referred to as
gastroparesis (Malczyk & Oświęcimska, 2017).
Physical Assessment and Exam
Patient who present with anorexia nervosa are more likely will deny that they are ill but their
skinny and weak appearance is evident. Patients will deny that they are hungry or report any
weight loss. However, patients usually report that they have abdominal discomfort, full after
eating small meals, bloating, and unable to fall asleep. On physical examination, bradycardia,
brittle hair and nails, thin body, hypotension, paleness, dryness, lanugo, edema, dental
erosions from acid reflux, and marked weight loss compare with age presented (Harrington,
Jimerson, Haxton, & Jimerson, 2015).
DSM-5 Criteria
Providers can diagnose anorexia nervosa by using the DSM-5 diagnostic criteria. The criteria
are divided into A, B, and C as follow:
A. Restriction of energy intake relative to requirements, leading to a significantly low body
weight in the context of age, sex, developmental trajectory, and physical health.
Significantly low weight is defined as a weight that is less than minimally normal or, for
children and adolescents, less than that minimally expected.
B. Intense fear of gaining weight or of becoming fat, or persistent behavior that interferes
with weight gain, even though at a significantly low weight.
C. Disturbance in the way in which one's body weight or shape is experienced, undue
influence of body weight or shape on self-evaluation, or persistent lack of recognition of
the seriousness of the current low body weight.
Laboratory Testing
Due to the volume loss and body waste from starvation, providers must order specific gravity
for hydration status, pH, ketones, and erythrocyte sedimentation rate. Vital signs such as
weight, height, body mass index, and body temperature must be included to help setting up
the treatment plan. Also, urinalysis with specific gravity, complete blood count, complete
metabolic panel, amylase and lipase measurement, phosphorous and magnesium
measurement, and thyroid function tests such as thyroid-stimulating hormone, thyroxine, and
free triiodothyronine. Providers may also order bone mineral density testing if patient has
been dieting for greater than six months (Harrington et al., 2015).
Evidence-Based Treatment Plan
A treatment plan is a multiteam approach due to the nature of the disorder. A
psychotherapist or psychiatrist is typically included in the plan of care. Eating disorder
specialists, usually with qualifications and background in psychiatry or adolescent med icine,
are impeccably engaged yet may not be accessible in some areas. A dietitian can assist select
nutritious and calorie-rich foods. For teens, it is important to include their schoolteachers
and administration. Most states require formal 504 plans that point out appropriate
accommodations, such as mini-breaks for snacks during class time or provide those in need
to miss school for rehabilitation so they can have an equal educational opportunity similar to
their peers. Treatment success may depend on placing a therapeutic partnership with the
patient, the patient's family, and collaboration with all the treatment team onboard or
involved in the treatment plan (Harrington et al., 2015).
An essential part of the treatment plan is setting goals with the patient. Patients with
anorexia nervosa may only consume 500 calories a day. However, daily average adolescent
caloric intake is usually 1,800 for females and 2,220 for males. The target weight gain in the
initial stages is 90% of the average weight based on the patient's height, age, and sex. The
provider must use the growth chart to keep track of the patient's weight gain changes.
Also, the patient’s provider must set goals such as agreeing on the weekly exercise plan
based on the weight gain, minimum acceptable weight gain, compliance with seeing either a
psychiatric or a psychologist, nutrition goals, and antidepressant medications such as
selective serotonin reuptake inhibitors (SSRIs) which it may help alleviate symptoms of
depression and suicidal ideation in patients with anorexia nervosa (Harrington et al., 2015).
Patient Education
Providers must educate their patients about the essential impact of the disorder and its
complications on their health. An explanation about the relationship between anorexia
nervosa, chronic symptoms, laboratory abnormalities, and the density of their bone must be
explained in detail (Abu-Baker et al., 2020; Harrington et al., 2015). Patients must be
reminded about visiting their dentist to prevent dental erosions and other dental disease due to
anorexia. They should be told to wear clothing that can fit them instead of wearing multiple
layers to eliminate the feeling of being overweight. Eating healthy balanced meals from all
food groups is critical for their reconstruction for their body and replenish from the inside out
(Abu-Baker et al., 2020; Silverstein, Haggerty, Sams, Phillips, & Roberts, 2019).
Patient must be assured that eating food does not cause gastroparesis; their symptoms will
resolve over four to six weeks when they follow the plan of care. Reassure patients that
constipation will resolve in few weeks after they return to their normal weight.
Follow up and evaluation
Follow up and evaluation is based on the care plan that is put forward by the multidisciplinary
team caring for the patient with anorexia nervosa. Initially, the goal is to make decisions on
short-term risk involved by making the assessment of the physical risk and the patient’s
psychological capacity to consent to the treatment by the multidisciplinary team. A referral to an
eating disorder program is a must and should be discussed with patient and family (Abu-Baker et
al., 2020; Harrington et al., 2015; Silverstein et al., 2019). Hospitalizations can be discussed as
well in certain cases. Visits with an outpatient dietitian can be helpful in maintaining nutrition
recovery. The dietitian follow-up can help with strengthening of behaviors that can support the
eating habits, monitor body weight, and body needs during the treatment plan. Treatment
evaluation is not all about consuming food but following up with psychiatrist or psychologist
especially if antidepressant medications have been prescribed is imperative (Abu-Baker et al.,
2020; Harrington et al., 2015; Silverstein et al., 2019).
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Sachs, K. V., Harnke, B., Mehler, P. S., & Krantz, M. J. (2016). Cardiovascular complications of
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Selby, E. A., & Coniglio, K. A. (2020). Positive emotion and motivational dynamics in anorexia
nervosa: A positive emotion amplification model (PE-AMP). Psychological Review.
Silverstein, L. S., Haggerty, C., Sams, L., Phillips, C., & Roberts, M. W. (2019). Impact of an
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