Objective: Information is scarce concerning the incidence of anorexia nervosa (AN) in psychiatric facilities in Iceland. The aim of this study was to describe the incidence of admissions, comorbidity and mortality of patients who were admitted to psychiatric units in Iceland, diagnosed with AN in 1983-2008.

Material and methods: The study is retrospective. 140 medical records with an AN or atypical eating disorder diagnosis according to the ICD-9 and ICD-10 were reviewed. Final sample was 84 patients with confirmed AN diagnosis.

Results: Five men and 79 women were admitted to a psychiatric inpatient ward for the first time diagnosed with AN. Average age was 18.7 years. Incidence of admissions for both sexes in the first part of the study period (1983-1995) was 1.43/100.000 persons/year, 11-46 years old, but in the second part (1996-2008) 2.91. The increase was statistically significant (RR=2.03 95% CI 1.28-3.22) and can mainly be explained by an increased incidence of admissions to the children- and adolescent psychiatric wards (CAW). Mortality of women was 2/79 (2.5%) and standard mortality rate 6.25. The average length of stay was 97 days, 67.3 days in adult units and 129.7 days in CAW (p<0.05). In the study period 51 patients (60.7%) were only admitted once. One patient had compulsory admission on his first admission but ten (11.9%) had at some point compulsory admission. The body mass index increased in average from admission to discharge from 15.3 to 17.5 kg/m². A correlation was found between self harm and suicide attempts and compulsory admissions.

Conclusion: The study revealed an increased incidence between periods. This might reflect a real increase of AN in the society. Mortality rate was lower than expected.