Monday, July 25, 2011

"Mortality Rates in Patients With Anorexia Nervosa and Other Eating Disorders:

Thank you to Joe Kelly of The Emily Program for sharing this article:

The new issue of *Archives of General Psychiatry* includes an article: "Mortality Rates in Patients With Anorexia Nervosa and Other Eating Disorders: A Meta-analysis of 36 Studies."

Jon Arcelus, LMS, MSc, FRCPsych, PhD; Alex J. Mitchell, MRCPsych; Jackie Wales, BA;& Søren Nielsen, MD.

Here's how the article starts:

[begin excerpt]

Eating disorders are increasingly recognized as an important cause of morbidity and mortality in young individuals.

The lifetime risk of anorexia nervosa (AN) in women is estimated to be 0.3% to 1%, with a greater number of patients having bulimia nervosa (BN).1-2

Anorexia nervosa is a serious psychiatric illness characterized by an inability to maintain an adequate, healthy body weight. Bulimia nervosa is characterized by recurrent episodes of binge eating in combination with some form of unhealthy compensatory behavior.

Eating disorder not otherwise specified (EDNOS) is a catchall DSM-IV diagnosis for patients with significant features of eating disorders that do not meet the criteria for AN or BN.3

Despite EDNOS being a common presentation in eating disorders services, few published data exist regarding mortality rates in patients given this diagnosis.4-5 Anorexia nervosa is a serious illness in the young population, and outcome is often poor.

Steinhausen6 showed that only 46% of patients fully recovered from AN, a third improved with only partial or residual features of the disorder, and 20% remained chronically ill for the long term.

A low body mass index (BMI), a greater severity of social and psychological problems, self-induced vomiting, and purgative abuse have been identified as predictors of poor outcome in this disorder.7

Most mortality research in the eating disorders literature has focused on AN.

Some authors have suggested that the mortality risk for BN is low.8

This conclusion is surprising, given the medical complications associated with self-induced vomiting, laxative abuse, and other purging behaviors.

The ratio of observed to expected deaths (ie, the standardized mortality ratio [SMR]) for AN has been reported to be between 0.719 and 12.8.10

Also, it often has been reported that suicide is a particularly common cause of death in AN.11-12 Muir and Palmer13 suggested that official death certification may underestimate the incidence of suicide associated with this disorder.

The wide variation of SMRs for eating disorders partly may depend on the length of follow-up.

For example, Nielsen14 reported an SMR of 9.6 after approximately 10 years of follow-up, as opposed to 3.7 in 4 studies with a mean follow-up period ranging from 20 to 36 years.

Other factors that correlate with a higher estimate of mortality are age, case severity, study period, and whether other eating disorders with a lower mortality rate were evaluated separately.15

Given this debate, the primary aim of our study was systematically to compile and to analyze mortality rates in individuals with eating disorders, taking into account variations in sampling, diagnosis, and length of follow-up of the study.

Our hypothesis was that mortality rates would be elevated in all types of eating disorders. We also aimed to explore factors associated with mortality among individuals with AN, BN, and EDNOS.

[end excerpt]

Here's an excerpt from the Discussion section:

[begin excerpt]

As hypothesized, we found an overall elevated mortality rate for patients with all types of eating disorders.

This risk of death was highest for those with AN, with a weighted annual mortality rate of 5 per 1000 person-years (slightly higher in studies of females only), followed by patients with EDNOS at 3 per 1000 person-years of follow-up and BN at 1.7 per 1000 person-years of follow-up.

The mortality rate, particularly for AN, was considerably lower for those studies that had a long follow-up period, such as that by Korndörfer et al,9 which showed an SMR for AN of 0.71 and had 27.1 years of follow-up, or the study by Crow et al,21 with an SMR of 1.7 and a follow-up of 18.13 years.

Studies15, 19, 40 with fewer years of follow-up generally showed a high SMR. Given the crossover observed between diagnoses, the actual duration of follow-up may be less important than the duration of illness.

[end excerpt]

Another excerpt: "Twelve studies described deaths from suicide in patients with AN, and analysis showed that the weighted annual mortality due to suicide in AN was 1.39, which means that 1 in 5 individuals with AN who died had committed suicide."

Another excerpt: "Our study found that the mortality rates in patients with eating disorders are high. In some cases (ie, those involving AN), they are much higher than for other psychiatric disorders. Studies in other psychiatric disorders have found SMRs of 2.8 and 2.5 in males and females with schizophrenia,54 1.9 and 2.1 in males and females with bipolar disorder, and 1.5 and 1.6 in males and females with unipolar disorder, respectively.55"

Another excerpt: "Based on the information from different studies, factors highlighted for poorer outcome, including mortality, in patients with AN included older age at first presentation,31, 36, 40 alcohol misuse,22, 34, 55 and low BMI at presentation.25, 34, 46 Other strong predictors of mortality involved comorbid disorders, such as affective disorder, suicidal behavior or self-harm, alcohol abuse, and a history of hospitalization for such mental health problems. Button et al22 found that only BMI at assessment and alcohol misuse reliably predicted mortality status, although evidence of an affective disorder almost was significant. Some studies24, 46 also have found evidence of an association between alcohol misuse and increased mortality in AN. One of them26 found that younger age and longer hospital stay at first hospitalization were associated with better outcome, and psychiatric and somatic comorbidity worsened the outcome of patients with eating disorders."

The author note gives the following contact information: Jon Arcelus, LMS, MSc, MRCPsych, PhD, Brandon Unit, Eating Disorders Service, Leicester Partnership Trust, Leicester General Hospital, Gwendolen Road, Leicester LE5 4PW, England (<J.Arcelus@lboro.ac.uk>).

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