IntroductionAnorexia Nervosa (AN) is an eating disorder identified by a weight which is 85% less than normal. An individual suffering from AN has a distorted view of their body image and self-perception. They view themselves as overweight when in fact the opposite is true. It is stated that they experience an intense fear of gaining weight which can result in self starvation as one restricts their food intake (Pawlowski, DeAngelo, 2013).According to Bell (2013), there are two types of AN: the restricting type, which includes dieting, fasting, and skipping meals, and the binge-eating/purging type which includes self-induced vomiting and use of laxatives to lose weight. While initially operant conditioning (the evident weight loss and praise received from others) maintains the food restriction, it inevitably becomes a classically conditioned habit (Coniglio, et al., 2017). Eating disorders are less likely to be treated successfully and AN has the highest mortality rate of all psychological disorders (Sepúlveda, et al.,2017).AetiologyIt is understood that when an individual has had a successful dieting experience, the continuation of the dieting can result in the development of anorexia nervosa. When one receives compliments and positive feedback while dieting, they are more likely to continue with their weight loss (Pawlowski, DeAngelo, 2013). Cognitive distortions (faulty thinking), may cause an individual to have a distorted view of body image and put emphasis on the perfect presentation (Bell, 2013).Anorexia nervosa can usually occur as a result of a traumatic experience such as death, divorce and sexual abuse. The condition is a physical manifestation due to intense emotions of guilt, anger, lack of control and poor body image. Eating disorders tend to run in families, usually ones that value thinness and perfection. (Pawlowski, DeAngelo, 2013). Children can be exposed continuous behavioural traits such as dissatisfaction with weight, eating disordered attitudes, weight preoccupation and dietary constraints within the home which makes them more vulnerable to developing AN (Kaye, et al., 2009).Anxiety disorders prevalence is high among those with AN. Kaye et al. (2004) state that anxiety disorders propose a vulnerability to developing AN as they have their onset in childhood before eating disorders. It was calculated that 42% of individuals with AN in a study had an anxiety disorder in childhood. This is important to note as the number of overall childhood anxiety disorders was 4.7% to 7.7% in 1995.Aetiological models for AN suggest that avoidance and compensatory behaviours are a result of fear conditioning to previously neutral stimuli – including food, eating behaviors, weight gain, etc. (Sepúlveda, et al.,2017).Kaye et al. (2009) highlight the role of the hypothalamus in food and weight regulation. However, it is unknown whether alterations of the hypothalamus have a role in the aetiology of AN.Diagnostic CriteriaAlthough the word “anorexia” translates to “loss of appetite”, one suffering with the condition still experiences intense hunger pain but ignores them (Pawlowski, DeAngelo, 2013). The body weight for an individual with AN is at or below 85% of normal.It is known that the primary characteristic of AN is “the relentless pursuit of thinness, with intense fear of fatness that does not diminish as the weight loss progresses”. Physical symptoms include extreme weight loss, dry skin with a yellowish tint, stringy hair and brittle nails, boney points are more visible and the abdomen is hollow. Food deprivation also results in a slow pulse, low blood pressure, anaemia and low BMR (Bruch, 1982). AN also results in amenorrhea which is an abnormal or absent menstrual discharge (Pawlowski, DeAngelo, 2013).According to the DSM 5, a person may be diagnosed with anorexia nervosa if they are considerably restricting their energy intake which leads to a significant reduction in body weight (in context of sex, age, physical health and developmental trajectory). They are already underweight but still have an intense fear of gaining weight, becoming fat, or show behaviours that interfere with weight gain. One also has “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 denial of the seriousness of the current low body weight.”(WEB)Body image disturbance is among the diagnostic criteria for AN. An anorexic individual takes pride in their appearance and does not see their body appearance as too thin. They will actively maintain it as they claim not to see their body as abnormal or “ugly”. An individual with AN seems to not understand the severity of their disorder and the serious medical consequences. Someone with this disorder also possesses a disturbed sense of their body’s state. They are unaware or in denial of their constant hunger, fatigue (Bruch, 1982).PrevalenceBell (2013) states that 4% percent of females have eating disorders. The National Association of Anorexia Nervosa and Associated Disorders declares that anorexia nervosa is most common among women and girls, although the numbers among males are rising. Overall it is proven that anorexia nervosa is the third most common chronic condition effecting adolescents and lifetime prevalence among adolescents in the United States is 0.3%(Pawlowski, DeAngelo, 2013) and 5.4% in Europe (Sepúlveda, et al.,2017).The media are a major contributor to this eating disorder. Images depicting the perfect body type confuses young consumers. It is known that in 2012, the average model weighed about 23 percent less than the average woman. Around 70 percent of American school girls who read magazines stated that the pictures of thin models have influenced their image of the ideal body shape and weight (Pawlowski, DeAngelo, 2013).Co morbiditiesIndividuals with anorexia nervosa may also have conditions like depression, social phobia, anxiety and obsessive-compulsive disorder. Obsessive behaviours may include repeatedly weighing one’s self several times a day, breaking food into small pieces, exercising compulsively and examining themselves frequently in a mirror (Pawlowski, DeAngelo, 2013). A large study was conducted where 55.2% ofparticipants met the criteria for at least one of the comorbid disorders, and 31.4% experienced suicidal ideation (Sepúlveda, et al.,2017).It is proven that autism spectrum disorder forms a strong comorbidity with anorexia nervosa. However, treatment for this comorbidity is poorly understood. Those with this comorbidity have shown poorer response to treatment and poorer illness outcomes. Individuals with AN express neurocognitive problems which are more associated with ASD. Prevalence among this common comorbidity ranges from 23 to 30 %. It is proven that those with this comorbidity present many treatment challenges to clinicians. This is due to problems regarding patient/therapist communication and identifying thoughts and emotions (Emma Kinnaird, Caroline Norton, Kate Tchanturia, 2017)There is a strong correlation between those who partake in athletic activities, including dance, gymnastics, cheerleading, and anorexia nervosa. It is also proven that individuals with anorexia nervosa generally are high achievers with “people pleasing” personalities (Pawlowski, DeAngelo, 2013).Individuals with AN may have issues regarding their gastrointestinal tract. Complaints regarding these issues can distract from the main goal of weight restoration during AN treatment. The elimination of certain food groups can make weight gain more difficult and can result in binging so knowledge of gastrointestinal comorbidities such as celiac disease, irritable bowel syndrome is useful.Treatment OptionsSepúlveda, et al. (2017) states that those suffering with eating disorders are less likely to be successfully treated and that Anorexia Nervosa has the highest mortality rate of all psychological disorders, 3.87 deaths per 1,000 person-years among women. Research carried out by The National Institute of Mental Health shows that one in ten cases ends in death due to starvation, kidney failure, heart attack, or suicide. Psychologists, nutritionists and physicians are all part of the multidisciplinary team required to treat the patient successfully (Pawlowski, DeAngelo, 2013). Treatment for AN can be difficult as the individual believes their diet and lifestyle is justified so resistance to treatment is experienced frequently (Bell, 2013).Most AN suffers require immediate hospitalisation if their weight is 75% less than normal or they have other urgent medical complications. Here they will receive daily monitoring of their caloric intake and they are weighed regularly. The duration of these stays varies from weeks to months, depending on the severity of the patient’s condition (Bell, 2013).The National Institute for Clinical Excellence recommends the following treatment options for those with AN: cognitive behavioral therapy (CBT), focal psychodynamic therapy, cognitive analytic therapy (CAT) and interpersonal psychotherapy (IPT) (Cara Freudenberg, et al., 2016).Cognitive Remediation Therapy (CRT) is a recent treatment option for children and adolescents with anorexia nervosa. It presents with positive results including an increase in an individual’s BMI, increased motivation, confidence in the patient’s ability to change, decreased eating disorder and improved neuropsychological performance (Hale, Kayleigh Elizabeth, 2016).Family therapy is an important form of therapy for patients as it encourages healthy communication, supportive behaviours and regular eating patterns (Bell, 2013).Patients who do not follow diet plans given to them by nutritionists may have to take caloric supplements. Methods like intravenous feeding or nasogastric intubation are used for AN treatment when necessary (Pawlowski, DeAngelo, 2013). In serious cases, coerced treatment is used but this is controversial and has clinical, legal and ethical implications. (Carney, et al., 2005).A study was designed to investigate relapse among patients who achieved clinical recovery and were discharged from hospital. They were assessed semiannually for 5 years and annually every 10-15 years thereafter. The study showed that nearly 30% of those patients relapsed. However, after the follow up nearly all of them were restored to a normal weight and regained menstruation (Strober, Freeman, Morrell, 1997).The American Academy of Child and Adolescent Psychiatry recommend outpatient treatments such as Family –Based Treatment, Adolescent Focused Therapy and Enhanced Cognitive Behavioral Therapy for the ?rst choice for adolescents with AN (Sepúlveda, et al.,2017).Zipfel et al. (2000) conducted a study which followed 84 patients 21 years after hospitalisation. It showed that 50.6% achieved full recovery from AN, while 10.4% still met full diagnostic criteria and 15.6% had died from anorexia nervosa complications.