OBJECTIVE: The purpose of this study was to examine the incidence of
anorexia nervosa and bulimia nervosa among patients in primary care and to
evaluate the impact of urbanization, age and sex differences, and changes
over time. METHOD: During 1985-1989, 58 general practitioners, trained in
diagnosing eating disorders, registered all of their patients who had
diagnoses of anorexia nervosa and/or bulimia nervosa according to strict
criteria. The study population (N = 151,781) was 1% of the population of
the Netherlands; the distribution of sexes, ages, geographical locations,
and degrees of urbanization in the study group was representative of the
Dutch population. Main outcome measures were rates of newly detected cases
and age-adjusted rate ratios. RESULTS: The crude annual incidence rate of
detected cases in primary care per 100,000 person-years was 8.1 for
anorexia nervosa and 11.5 for bulimia nervosa. The incidence of bulimia
nervosa was lowest in rural areas, intermediate in urbanized areas, and
highest in large cities (6.6, 19.9, and 37.9, respectively, per 100,000
females per year); no rural- urban differences for anorexia nervosa were
found. Pronounced sex and age differences in incidence rates were observed.
Over the 5-year period, there was no time trend in the incidence of
anorexia nervosa, but the incidence of bulimia nervosa tended to increase.
CONCLUSIONS: The incidence rates of eating disorders--as defined by
detection rates in primary care--are higher than previously reported.
Urbanization seems to be a risk factor for bulimia nervosa but not for