Anorexia nervosa is characterised by a low body mass index (BMI), fear of gaining weight, denial of current low weight and its impact on health, and amenorrhoea. Estimated prevalence is highest in teenage girls, and up to 0.7% of this age group may be affected. While most people with anorexia nervosa recover completely or partially, about 5% die of the condition, and 20% develop a chronic eating disorder. Young women with anorexia nervosa are at increased risk of bone fractures later in life.
Methods and outcomes
We conducted a systematic review, and aimed to answer the following clinical questions: What are the effects of treatments in anorexia nervosa? What are the effects of interventions to prevent or treat complications of anorexia nervosa? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
We found 40 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
In this systematic review we present information relating to the effectiveness and safety of the following interventions: atypical antipsychotic drugs, benzodiazepines, cyproheptadine, inpatient/outpatient treatment setting, oestrogen treatment (HRT or oral contraceptives), older-generation antipsychotic drugs, psychotherapy, refeeding, selective serotonin reuptake inhibitors (SSRIs), and tricyclic antidepressants.
Anorexia nervosa is characterised by a low body mass index (BMI), fear of gaining weight, denial of current low weight and its impact on health, and amenorrhoea.
Estimated prevalence is highest in teenage girls, and the condition may affect up to 0.7% of this group.Anorexia nervosa is related to family, sociocultural, genetic, and other biological factors. Psychiatric and personality disorders such as depression, anxiety disorders, obsessive compulsive disorder, and perfectionism are commonly found in people who have anorexia nervosa.Most people with anorexia nervosa recover completely or partially, but about 5% die from the condition and 20% develop a chronic eating disorder.Young women with anorexia nervosa are at increased risk of fractures later in life.Population assessment indicates that risks to fertility may be overstated in those who reach a healthy BMI, but children born to mothers who have recovered from anorexia nervosa seem to have lower birth weights.
There is no strong RCT evidence that any treatments work well for anorexia nervosa. However, there is a gradual accumulation of evidence suggesting that early intervention is effective. Increasing evidence suggests that working with the family may also interrupt the development of a persistent form of the illness, when this work begins early in the disease.
Evidence on the benefits of psychotherapy is unclear.
Refeeding is a necessary and effective component of treatment, but is not sufficient alone.
Very limited evidence from a quasi-experimental study suggests that a lenient approach to refeeding is as effective and more acceptable compared with a more strict approach.Refeeding may be as effective in an outpatient setting as during hospital admission.Nasogastric refeeding has been used to speed up weight gain in inpatient observational studies, although it is rarely studied in RCTs. Very limited RCT evidence suggests that adding nasogastric feeding to oral nutrition can increase weight gain and reduce relapse in the short term more than oral nutrition alone, but these gains are not maintained at 1 year post-discharge. Given ethical and medical concerns with tube feeding, this approach is encouraged with caution.Nutritional supplements, including zinc, have only limited evidence for their effectiveness, and additional evaluations of these measures are warranted.
We don't know whether inpatient or outpatient treatment is more effective in people with anorexia nervosa.
Limited evidence from small RCTs has not shown significant weight gain from SSRIs or tricyclic antidepressants, some of which may cause serious adverse effects.
Tricyclic antidepressants may cause drowsiness, dry mouth, blurred vision, and a prolonged QT interval in people who have anorexia nervosa.
SSRIs have not been shown to be beneficial, but the evidence remains very limited; in the 4 RCTs we found, conclusions were limited because of small trial size and high rates of withdrawal.
Older-generation antipsychotic drugs may prolong the QT interval, increasing the risk of ventricular tachycardia, torsades de pointes, and sudden death.
Atypical antipsychotics have been evaluated for their potential role in reducing agitation and anxiety related to refeeding, as well as for potentially increasing appetite. Increasing observational data (case series) have suggested that they may decrease obsessiveness and agitation. However, further evidence from large, well-conducted RCTs is necessary to draw reliable conclusions. Newer atypical antipsychotics, in particular olanzapine, do not seem to be associated with the same cardiac risks as older-generation antipsychotic drugs, but the known association between olanzapine and weight gain may impact compliance in people with anorexia nervosa. However, further research needs to be done.
We found insufficient RCT evidence assessing benzodiazepines or cyproheptadine for treating anorexia nervosa.
Oestrogen treatment has been hypothesised to reduce the negative effects on bone mineral density associated with anorexia nervosa. However, three small RCTs have failed to demonstrate clinically relevant changes in bone mineral density after treatment with oestrogen either HRT or oral contraceptives), and these results are supported by 2-year longitudinal data, which found similar lack of improvement.