Epidemiology

Lifetime prevalence of anorexia nervosa (AN) in the US according to DSM-5 criteria is approximately 0.8%.[5]​ 

Prevalence of AN varies globally. Systematic reviews incorporating a range of studies from around the world estimate overall lifetime prevalence rates of 0.2%, with higher rates seen within studies using DSM-5 criteria (0.9%). Studies on the prevalence of eating disorders are limited, and are concentrated within Europe, America, Australia, New Zealand, China and South Korea.[6]​ AN is studied more in developed countries where the disorder is more commonly found.[7][8]​​​​​ Although very few individuals who diet in an attempt to lose weight develop AN, the illness occurs more frequently in cultures where pursuit of thinness is prized. Cross-cultural studies have linked increases in eating disorders to Western media exposure and ideals, and there is evidence that attitudes that may increase risk for eating disorders are increasing in non-Western countries.[9] Of note, rates of anorexia within Asian countries have increased substantially since 2000; rates within the past decade are now comparable to those seen in Western countries.[9][10]​​​​[11][12]

Sound epidemiological data are difficult to obtain, but the best available information indicates that the incidence of AN (number of new diagnoses per year) has not changed substantially in the past three decades.[12][13][14]​​[15]​​​​ However, there is evidence to suggest an increased incidence in children (aged <15  years), and in particular younger children (aged ≤12 years), in more recent years.[16][17][18][19]​ Onset before 15 years is associated with greater illness severity and higher rates of lifetime psychiatric comorbidity.[20]

According to strict diagnostic criteria, about 0.3% of people in westernised countries, with about 0.5% to 1% of college-aged women, are affected.[21][22]​​​ It is estimated that 3 in 10 patients are male, but many males may not present for treatment; thus, about 90% of patients diagnosed are female.[15][18]​​ Some reports have suggested that the relative prevalence of AN among pre-adolescent boys to approach a ratio of boys to girls of 1:4.[23] Males may be less likely to be diagnosed, potentially due to both underreporting of symptoms and lower levels of suspicion among healthcare professionals.[24]

The risk of onset for AN is highest in late adolescence, with 40% of new illness occurring in patients between aged 15 and 19 years.[13][17]​​[18]​​ The risk of developing AN drops significantly after 21 years of age, although the menopausal period has been suggested as an additional high-risk period in women for the onset or recurrence of an eating disorder.[25][26]

Only one third of people with AN seek medical care.[27] ​Some studies report that white women are more likely to be diagnosed with AN than women from other ethnic and racial groups, although evidence is mixed.[5][28][29]​​​ Prevalence appears higher in people who identify as lesbian, gay, bisexual, transgender, queer or questioning (LGBTQ+) compared with heterosexual/cisgender peers.[30][31]​​​

Among psychiatric illnesses, AN has one of the highest premature mortality rates (with a risk of premature death of approximately fivefold greater than that of peers).[32][33]​​​​ Deaths are due primarily to medical complications or suicide.[34][35]​​​​​ Co-occurring psychiatric conditions are common, and may enhance mortality risk, including risk of suicide. Comorbid conditions include depression, anxiety, posttraumatic stress disorder, obsessive compulsive disorder, attention deficit hyperactivity disorder, and substance use disorders.[36][37][38]​ The presence of co-occurring diabetes substantially increases the risk of death compared to in people with diabetes without an eating disorder.[39]

Use of this content is subject to our disclaimer