More people are being diagnosed with eating disorders every
year and the most common type is not either of the two most well known—bulimia
or anorexia—but eating disorders not otherwise specified (eating disorders that
don't quite reach the threshold to be defined as anorexia or bulimia), shows a
study published online in BMJ Open.
Few studies have investigated the incidence of eating
disorders, so the authors set out to determine the incidence of diagnosed
anorexia nervosa, bulimia nervosa and other non-specified eating disorders in
primary care over a 10-year period in the UK (2000), to see how the incidence
had changed and the most common age of diagnosis.
Eating disorders have the highest death rates of all mental
disorders, and understanding changes in their incidence over time and by age
and gender is essential to ensure timely diagnosis and appropriate service
How the study was
The researchers used data from the General Practice
Database, which contains anonymised records of 5% of the UK population to
identify all cases of eating disorder diagnosed between 2000 and 2009. They
found a total of 9072 cases.
Analysis of the data revealed that in 2000 there were 32.3
new cases of eating disorder per 100 000 population aged between 10 and 49
years, and that this rose steadily to 37.2 new cases per 100 000 by 2009.
Despite other research suggesting a decrease in the
incidence of bulimia, the incidence of bulimia and anorexia remained stable
over the 10 years and it was new cases of eating disorder not otherwise
specified which were responsible for the overall rise. The incidence of these
unspecified eating disorders, which have been far less studied than bulimia and
anorexia and are the most common type seen in hospital care (60% of cases seen
in specialist services), has not been estimated previously in general practice
However, publication of the new Diagnostic and Statistical
Manual of Mental Disorders (DSM 5) last week is expected to mean that the
majority of these cases will be diagnosed with anorexia, bulimia or a new
condition of binge eating disorder in future.
The data showed that girls aged 15 to 19 years and boys aged
10 to 14 had the highest incidences of new diagnoses of eating disorder.
Two girls in every 1000 aged 15 to 19 years are likely to be
diagnosed with an eating disorder every year, which means that there are around
4610 new cases in girls of this age group each year. As a result, eating
disorder is probably the most common new onset mental health disorder in
adolescent girls after depression, the authors say. In 2009, the incidence of
new diagnoses of depression was 11.9 per 1000 in girls of this age group.
In girls aged 10-19 years, there are nine times as many new
cases of eating disorder (1.2 per 1000 population) diagnosed every year as
there are cases of type 1 diabetes (0.26 new cases per 1000), and about half as
many new diagnoses as there are of type 2 diabetes (3.6 new cases per 1000).