than in the general population, and the suicide risk is 56 times higher. half of women with an achieve a full recovery, while an additional 20–30% may partially recover. not all people with anorexia recover completely: about 20% develop anorexia nervosa as a chronic disorder. if anorexia nervosa is not treated, serious complications such as heart conditions and kidney failure can arise and eventually lead to death. the average number of years from onset to remission of an is seven for women and three for men. after ten to fifteen years, 70% of people no longer meet the diagnostic criteria, but many still continue to have eating-related problems. alexithymia (inability to identify and describe one's own emotions) influences treatment outcome. recovery is also viewed on a spectrum rather than black and white. according to the morgan-russell criteria, individuals can have a good, intermediate, or poor outcome. even when a person is classified as having a "good" outcome, weight only has to be within 15% of average, and normal menstruation must be present in females. the good outcome also excludes psychological health. recovery for people with anorexia nervosa is undeniably positive, but recovery does not mean a return to normal. complications anorexia nervosa can have serious implications if its duration and severity are significant and if onset occurs before the completion of growth, pubertal maturation, or the attainment of peak bone mass. complications specific to adolescents and children with anorexia nervosa can include the following: growth retardation may occur, as height gain may slow and can stop completely with severe weight loss or chronic malnutrition. in such cases, provided that growth potential is preserved, height increase can resume and reach full potential after normal intake is resumed. height potential is normally preserved if the duration and severity of illness are not significant or if the illness is accompanied by delayed bone age (especially prior to a bone age of approximately 15 years), as hypogonadism may partially counteract the effects of undernutrition on height by allowing for a longer duration of growth compared to controls. appropriate early treatment can preserve height potential, and may even help to increase it in some post-anorexic subjects, due to factors such as long-term reduced estrogen-producing adipose tissue levels compared to premorbid levels. in some cases, especially where onset is before puberty, complications such as stunted growth and pubertal delay are usually reversible. anorexia nervosa causes alterations in the female reproductive system; significant weight loss, as well as psychological stress and intense exercise, typically results in a cessation of menstruation in women who are past puberty. in patients with anorexia nervosa, there is a reduction of the secretion of gonadotropin releasing hormone in the central nervous system, preventing ovulation. anorexia nervosa can also result in pubertal delay or arrest. both height gain and pubertal development are dependent on the release of growth hormone and gonadotropins (lh and fsh) from the pituitary gland. suppression of gonadotropins in people with anorexia nervosa has been documented. typically, growth hormone (gh) levels are high, but levels of igf-1, the downstream hormone that should be released in response to gh are low; this indicates a state of "resistance" to gh due to chronic starvation. igf-1 is necessary for bone formation, and decreased levels in anorexia nervosa contribute to a loss of bone density and potentially contribute to osteopenia or osteoporosis. anorexia nervosa can also result in reduction of peak bone mass. buildup of bone is greatest during adolescence, and if onset of anorexia nervosa occurs during this time and stalls puberty, low bone mass may be permanent. hepatic steatosis, or fatty infiltration of the liver, can also occur, and is an indicator of malnutrition in children. neurological disorders that may occur as complications include seizures and tremors. wernicke encephalopathy, which results from vitamin b1 deficiency, has been reported in patients who are extremely malnourished; symptoms include confusion, problems with the muscles responsible for eye movements and abnormalities in walking gait. the most common gastrointestinal complications of anorexia nervosa are delayed stomach emptying and constipation, but also include elevated liver function tests, diarrhea, acute pancreatitis, heartburn, difficulty swallowing, and, rarely, superior mesenteric artery syndrome. delayed stomach emptying, or gastroparesis, often develops following food restriction and weight loss; the most common symptom is bloating with gas and abdominal distension, and often occurs after eating. other symptoms of gastroparesis include early satiety, fullness, nausea, and vomiting. the symptoms may inhibit efforts at eating and recovery, but can be managed by limiting high-fiber foods, using liquid nutritional supplements, or using metoclopramide to increase emptying of food from the stomach. gastroparesis generally resolves when weight is regained. cardiac complications anorexia nervosa increases the risk of sudden cardiac death, though the precise cause is unknown. cardiac complications include structural and functional changes to the heart. some of these cardiovascular changes are mild and are reversible with treatment, while others may be life-threatening. cardiac complications can include arrhythmias, abnormally slow heart beat, low blood pressure, decreased size of the heart muscle, reduced heart volume, mitral valve prolapse, myocardial fibrosis, and pericardial effusion. abnormalities in conduction and repolarization of the heart that can result from anorexia nervosa include qt prolongation, increased qt dispersion, conduction delays, and junctional escape rhythms. electrolyte abnormalities, particularly hypokalemia and hypomagnesemia, can cause anomalies in the electrical activity of the heart, and result in life-threatening arrhythmias. hypokalemia most commonly results in patients with anorexia when restricting is accompanied by purging (induced vomiting or laxative use). hypotension (low blood pressure) is common, and symptoms include fatigue and weakness. orthostatic hypotension, a marked decrease in blood pressure when standing from a supine position, may also occur. symptoms include lightheadedness upon standing, weakness, and cognitive impairment, and may result in fainting or near-fainting. orthostasis in anorexia nervosa indicates worsening cardiac function and may indicate a need for hospitalization. hypotension and orthostasis generally resolve upon recovery to a normal weight. the weight loss in anorexia nervosa also causes atrophy of cardiac muscle. this leads to decreased ability to pump blood, a reduction in the ability to sustain exercise, a diminished ability to increase blood pressure in response to exercise, and a subjective feeling of fatigue. some individuals may also have a decrease in cardiac contractility. cardiac complications can be life-threatening, but the heart muscle generally improves with weight gain, and the heart normalizes in size over weeks to months, with recovery. atrophy of the heart muscle is a marker of the severity of the disease, and while it is reversible with treatment and refeeding, it is possible that it may cause permanent, microscopic changes to the heart muscle that increase the risk of sudden cardiac death. individuals with anorexia nervosa may experience chest pain or palpitations; these can be a result of mitral valve prolapse. mitral valve prolapse occurs because the size of the heart muscle decreases while the tissue of the mitral valve remains the same size. studies have shown rates of mitral valve prolapse of around 20 percent in those with anorexia nervosa, while the rate in the general population is estimated at 2–4 percent. it has been suggested that there is an association between mitral valve prolapse and sudden cardiac death, but it has not been proven to be causative, either in patients with anorexia nervosa or in the general population. relapse rates of relapse after treatment range 30-72% over a period of 2-26 months, with a rate of approximately 50% in 12 months after weight restoration. relapse occurs in approximately a third of people in hospital, and is greatest in the first six to eighteen months after release from an institution. bmi or measures of body fat and leptin levels at discharge were the strongest predictors of relapse, as well as signs of eating psychopathology at discharge. duration of illness, age, severity, the proportion of an binge-purge subtype, and presence of comorbidities are also contributing factors. epidemiology anorexia is estimated to occur in 0.9% to 4.3% of women and 0.2% to 0.3% of men in western countries at some point in their life. about 0.4% of young females are affected in a given year and it is estimated to occur three to ten times less commonly in males. rates in most of the developing world are unclear. often it begins during the teen years or young adulthood. medical students are a high risk group, with an overall estimated prevalence of 10.4% globally. the lifetime rate of atypical anorexia nervosa, a form of ed-nos in which the person loses a significant amount of weight and is at risk for serious medical complications despite having a higher body-mass index, is much higher, at 5–12%. while anorexia became more commonly diagnosed during the 20th century it is unclear if this was due to an increase in its frequency or simply better diagnosis. most studies show that since at least 1970 the incidence of an in adult women is fairly constant, while there is some indication that the incidence may have been increasing for girls aged between 14 and 20. underrepresentation eating disorders are less reported in preindustrial, non-westernized countries than in western countries. in africa, not including south africa, the only data presenting information about eating disorders occurs in case reports and isolated studies, not studies investigating prevalence. western countries experience slightly higher rates of eating disorders than non-western countries. theories to explain these lower rates of eating disorders, lower reporting and lower research rates in include the effects of westernisation, and culture change. men (and women) who might otherwise be diagnosed with anorexia may not meet the dsm-iv criteria for bmi since they have muscle weight, but have very little fat. in many cases a subclinical "not otherwise specified" diagnosis is made instead; ed-nos in the dsm-iv, and other specified feeding or eating disorder or unspecified feeding or eating disorder in the dsm-5. ed-nos was the most diagnosed eating disorder in 2009, and it was also shown that an did not differ significantly in eating pathology or general psychopathology from ednos involving restrictive eating. the elderly population is increasingly experiencing anorexia nervosa, which has been termed the "anorexia of aging". the eating disorder is similar to that of typical anorexia nervosa but is more often accompanied by the overuse of laxatives in order to purge the individual of ingested food. most geriatric anorexia patients limit their food intake to dairy or grains, whereas an adolescent anorexic has a more general limitation. this eating disorder that affects older adults has two types - early onset and late onset. early onset refers to a recurrence of anorexia in late life in an individual who experienced the disease during their youth. late onset describes instances where the eating disorder begins for the first time late in life. the stimulus for anorexia in elderly patients is typically a loss of control over their lives, which can be brought on by many events, including moving into an assisted living facility. this is also a time when most older individuals experience a rise in conflict with family members, such as limitations on driving or limitations on personal freedom, which increases the likelihood of an issue with anorexia. there can be physical issues in the elderly that leads to anorexia of aging, including a decline in chewing ability, a decline in taste and smell, and a decrease in appetite. psychological reasons for the elderly to develop anorexia can include depression and bereavement, and even an indirect attempt at suicide. there are also common comorbid psychiatric conditions with aging anorexics, including major depression, anxiety disorder, obsessive compulsive disorder, bipolar disorder, schizophrenia, and dementia. the signs and symptoms that go along with anorexia of aging are similar to what is observed in adolescent anorexia, including sudden weight loss, unexplained hair loss or dental problems, and a desire to eat alone. there are also several medical conditions that can result from anorexia in the elderly. an increased risk of illness and death can be a result of anorexia. there is also a decline in muscle and bone mass as a result of a reduction in protein intake during anorexia. another result of anorexia in the aging population is irreparable damage to kidneys, heart or colon and an imbalance of electrolytes. many assessments are available to diagnose anorexia in the aging community. these assessments include the simplified