BACKGROUND: This paper examines the evidence that rates of anorexia nervosa have increased over time. METHOD: Epidemiological studies that have provided time trends in incidence rates in specific countries or psychiatric registers and prevalence surveys were reviewed to assess whether or not prevalence estimates are higher in the most recent studies. RESULTS: Estimated trends in incidence rates showed an increase but no study ruled out plausible alternative explanations. Studies showing no upward trend were as numerous and were generally based on larger samples. Analysis of 29 cross-sectional surveys conducted over the last 25 years indicated that the median prevalence rate was 1.3 per 1000 females. There was no indication that more recent surveys yielded higher prevalence rates. CONCLUSION: Anorexia nervosa remains a rare disorder and there is no evidence of a secular increase in its incidence.
BACKGROUND: This paper examines the evidence that rates of anorexia nervosa have increased over time. METHOD: Epidemiological studies that have provided time trends in incidence rates in specific countries or psychiatric registers and prevalence surveys were reviewed to assess whether or not prevalence estimates are higher in the most recent studies. RESULTS: Estimated trends in incidence rates showed an increase but no study ruled out plausible alternative explanations. Studies showing no upward trend were as numerous and were generally based on larger samples. Analysis of 29 cross-sectional surveys conducted over the last 25 years indicated that the median prevalence rate was 1.3 per 1000 females. There was no indication that more recent surveys yielded higher prevalence rates. CONCLUSION:Anorexia nervosa remains a rare disorder and there is no evidence of a secular increase in its incidence.