AN is most often associated with obesity and insulin resistance.[2][7] It is the most common dermatological manifestation of obesity.[16] As rates of obesity rise globally, so does the incidence of AN.[7][17] AN is very common in dark-skinned populations throughout the world, but is rare in white people.[18] AN is found in 21% to 74% of selected adult populations and 17% of urban youth in the US.[19][20][7] The prevalence of AN varies from 7% to 74%, depending on the type of AN and on patient factors; including age, race, and presence of obesity and associated endocrinopathy.[17] A study of 1133 patients in southwest US found a prevalence ratio for type 2 diabetes in patients with AN of 1.97.[19] Children with AN are up to 4.2 times as likely to have hyperinsulinaemia as those without.[21] In one study of 618 urban youths, AN was found in 62% of subjects with a BMI >98th percentile and was more common in ethnic minorities, with 23% of Hispanic, 19% of black, and 4% of white people affected.[7] Malignant AN is rare, although the exact incidence is unknown. It is reportedly present in 2 out of 12,000 patients with cancer.[22] There have been over 1000 reported cases in the world literature.[23] It is reported most often in adults over the age of 40 years and has no sex or racial predilection.[9]

BMJ Best Practice is an evidence-based point of care tool for healthcare practitioners.

To continue reading and access all of BMJ Best Practice's pages you'll need to log in or start a free trial.

You can access through your institution if your hospital, university, trust or other institution provides access to BMJ Best Practice through either OpenAthens or Shibboleth.

Use of this content is subject to our disclaimer