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Anorexia nervosa

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Defined as an individual with an intense fear of gaining weight, undue emphasis on body shape, having a body weight less than 85% of predicted weight and missing three consecutive periods.

A severe psychiatric disorder characterized by starvation and malnutrition

Associated with a high incidence of coexisting psychiatric disorders, treatment resistance, and a substantial risk of death from medical complications and suicide.

Coexisting psychiatric conditions include: major depression, anxiety disorders, obsessive compulsive disorder, trauma-related disorders, and substance abuse.

Self-induced starvation.

Anorexia nervosa is a mental disorder characterized as severe dietary restriction and intense fear of weight gain.

Patients  with anorexia nervosa may exercise ritualistically.

Individuals who have anorexia have high levels of ghrelin, a hormone that stimulates appetite, so the body is trying to cause hunger, but the urge to eat is being suppressed by the person.

Prevalence approximately 0.5 to 1% and is highest among adolescent girls and young women.

Approximately 92% of affected patients or female.
It occurs less commonly among blacks and Hispanics than among white population.

Global incidence is increasing particularly in Asia and the Middle East.

Characterized by body weight at least 15%, what is expected.

The psychiatric illness with the highest mortality rate.

Approximately 50% of adolescent patients with anorexia nervosa have it least one comorbid psychiatric illness.

Patients experience fear of weight gain and undo focus on their weight and shape.

Amenorrhea presently required for the diagnosis.

Medical complications or related to weight loss: malnutrition and conditions related to purging.
Self-induced vomiting may be related to salivary gland a purchase fee, and elevated levels of serum amylase, delayed gastric emptying, post prandial fullness, bloating,
 
Binge eating can also be associated with gastric dilatation resulting in rupture, and vomiting rarely may result in esophageal rupture.
Intermittent constipation, and more infrequently diarrhea can occur.
Cardio vascular abnormality’s include bradycardia, hypotension, arrhythmias, and prolonged QT interval.
Overtime, volume depletion and hypokalemia may result.
End stage renal disease has been reported in about 5% of patients over a prolonged follow up period.
May be associated with impaired bone marrow activity with pancytopenia, loss of muscle mass, and osteoporosis.
Osteoporosis develops in approximately 1/3 of patients.
The restoration of weight and resumption of menses can improve bone density, and is the primary strategy for management of osteoporosis.
Adequate calcium intake and vitamin D supplementation when blood levels are low are recommended.
Oral contraceptives did not appear to be effective for reducing bone loss in patients with AN.
Some evidence for transdermal estrogen in patients with AN with increasing spine and hip z scores over a period of 18 months.
Bisphosphonates  are generally not used in adolescence.
Imaging studies reveal abnormalities of ventricular dilatation, and cerebral atrophy, and neurocognitive findings include cognitive rigidity.

Classified into two subtypes: one) , restricting subtype and two) binge eating/purging subtype.

Restricting subtype refers to patients with anorexia nervosa, who rarely binge eat , or purge but have a fairly regular pattern of caloric restriction.

Binge eating/purging subtype reflects patients who regularly engage in binge eating or compensatory behavior to prevent weight gain.

Generally starts with weight loss from dieting, although weight loss due to a medical illness may also be an initiating process.

Excessive interest in weight loss, often purge, and abuse of diuretics and purgatives is common.

There is an extreme focus on body weight and shape that is integral to the disorder, combined with complete control over everything that is eaten including the preparation of food.

Intense fear of weight gain is an essential feature, patient often deny this fact and it must be inferred from their behavior.

Causes are multifactorial and include genetics, personality traits of perfection and compulsiveness, anxiety disorders, family history of depression and obesity, and pressure of culture, family and peers with respect to physical appearance.

Can evolve into a chronic process and has significant physical consequences of severe weight loss, and psychological comorbidity conditions that contribute to a significant mortality, with suicides making up a large number of deaths ( Sullivan PF).

Depression is frequently a comorbidity feature and often resolves with re-feeding (Fairburn CG).

There are two subtypes: the restricting subtype, characterized by dietary restriction, and binge-eating and purging subtype, in which restriction is accompanied by binge eating, purging, or both.

The underlying condition may progress from one subtype to another.

Many patients with restrictive subtype will develop binge eating/purging, with at least one third of patients crossing over to bulimia.

Crossover into binge eating and bulimia usually occurs within the first 5 years of the illness.

The restricting subtype is associated with an earlier age of onset, and a better prognosis, with a greater likelihood of cross over to the other subtype.
The onset of AN usually occurs in adolescence or young adulthood.

The lifetime prevalence is approximately 0.8%.

Patients that develop bulimia will likely relapse back into anorexia nervosa.

Recovery rate 35-85% and ranges from 57-79 months.

A long term course in 20-year longitudinal studies suggest full remission in approximately 30-60% of patients, chronic illness in 20%, and residual symptoms in the remainder.
The incidence of relapse after treatment ranges from 9-52%, with most studies showing an incidence of at least 25%.
Mortality rate nears 5.6% per decade

Recovery is prolonged, showing recovery in approximately 31% at nine years, but almost 2/3 of patients by 22 years.

Anxiety is common and often precedes the development of anorexia nervosa.

Patients require rapid medical attention and monitoring of dehydration, electrolyte abnormalities, renal problems, arrhythmias, cardiac impairment and refeeding syndrome.

Metabolic acidosis is the most common acid-base abnormality in patients with eating disorders.

Hypophosphotemia may rapidly occur with refeeding.

The refeeding  syndrome may occur rarely and is associated with rapid shifts in fluids and electrolytes and can result in hypomagnesemia,  hypokalemia, gastric dilatation and severe edema and many causes cardiac arrhythmias, delirium, coma and death (Mehanna MH).

The refeeding  syndrome can be prevented by the gradual re-feeding of severely  malnourished patients.

The use of phosphorus supplementation is required and the goal of treatment is to keep phosphorus levels above 3.0 mg per deciliter.

Excessive interest in weight loss, often purge, and abuse of diuretics and purgatives is common.

Disorder tends to occur in families, and twin studies suggest significant genetic contribution to developing the disease.

Twin-based studies estimate 50-60% hereditary familial aggregation.
There are eight risk loci for anorexia nervosa also predictive of other psychiatric disorders as well as low BMI and metabolic derangements.
Other risk factors include a history of trauma and living in a society with high values on thI less..
 
Perinatal factors associated with increased risk have been identified and include in utero exposure to rubella, multiple births and preterm birth.
Psychological risk factors include cognitive rigidity, perfectionism, and childhood anxiety disorders.

Social factors play a role in the development of the process with increases prevalence in cultures promoting thinness.

Overvalue thinness.

Distorted perception of body weight.

Intense pursuit of thinness.

Associated with overlap symptoms with many other psychiatric mood and anxiety disorders.

Associated with significant physiological dysfunction.

Phobic avoidance of many foods.

Usually begins during adolescence.

Frequently accompanied by compulsive exercising.

Subgroups have purging behavior resulting in sustained low body weight.

Purging usually starts after dieting begins and consists of self induced vomiting, laxative abuse, diuretic abuse and dist pill usage.

Two types: restricting and binge-eating subtypes.

In the binging type food intake may range from small amounts to several thousand calories.

In young women the risk of developing anorexia is 0.5 to 1 percent, with a mortality rate of 4-10%.

Lifetime risk for women 0.3-1% and for men about one tenth of that rate.

12-18 % prevalence of drug abuse.

50% of patients have a good prognosis, 30% have an intermediate outcome and 20% have a poor outcome.

Patients have a mortality rate six times that of peers without anorexia.

Almost all organs are disrupted with presentation of symptoms: bradycardia, dehydration, hypotension, amenorrhea, anemia and leucopoenia, electrolyte disorders.

With severe disease osteopenia, osteoporosis, prolonged QT interval, impaired gastric motility, elevated liver function tests, renal insufficiency , hair loss, and the presence of lanugo.

Likely that starvation promotes depression, anxiety, insomnia, decreased libido, with bizarre food rituals.

Aggregate rate of death 5.6% per decade (Sullivan).

Death rate as high as any psychiatric disease.

Deaths commonly due to suicide or cardiac arrhythmias.

Suicide risk among patients with AN estimated incidence is 18 times as high as controls.

Decrease in incidence of breast cancer related to caloric restriction.

Treatment includes nutritional rehabilitation, cognitive-behavioral or cycle therapy and family therapy.

For patients with profound hypotension and dehydration, severe electrolyte abnormalities, arrhythmias, severe bradycardia, and suicide risk may require immediate hospitalization.
A BMI of 15 or less indicates hospitalization is warranted.

Involuntary treatment may be required in life-threatening situations.

Minimal evidence existed psychiatric medications or efficacious in treatment.

Anti-depressants do not ameliorate the eating disorder patients who are acutely under weight.

Testing includes measurements of levels of Sejm and electrolytes, calcium, phosphorus, magnesium, fasting blood glucose, albumin, pre-albumin, amylase, lipids, CBC and electrocardiography.
Refeeding protocols initially utilized 1200 kcal per day to minimize the risk of re-feeding syndrome:Presently,more aggressive refeeding programs have been demonstrated to be safe for the majority of patients.
Psychotherapy is the mainstay of management.
Cognitive behavioral therapy targets eating and exercise behaviors as well as negative thoughts about eating, weight and body shape.
Most psychopharmacological agents are not effective in the management of an anorexia nervosa.
Trials of various anti-depressant drugs have not been more effective than psychotherapy alone and increasing weight, improving depression symptoms, or doing the incidence of relapse.

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