Inpatient mental health settings have been described as “obesogenic” environments, due to factors including psychotropic medication, high calorie food, restricted physical activity and sedentary lifestyles. No research has investigated obesity among forensic intellectual disability inpatients, despite this populations’ increased risk. Therefore, this paper aims to evaluate the prevalence and correlates of overweight and obesity on, and during admission.

The weight and body mass index data of 46 inpatients (15 women and 31 men) within a specialist intellectual disability forensic service was examined for the study.

Only six patients (13%) were a normal weight at admission, whereas 40 (87%) were overweight or obese. During their admission, 28 (61%) gained weight (average 11.8 kg), and one (2%) maintained. However, 17 patients (37%) lost weight (average 6.2 kg), though 16 remained in overweight/obese categories. There was no correlation between length of stay and weight/BMI.

The majority of patients were overweight or obese on admission, and approximately 60% gained weight during their admission. Women appeared at greater risk of obesity. There was no relationship between length of stay and weight. This is potentially due to the high prevalence of obesity on admission and the impact of previous admissions on weight. The results highlight the need for effective weight management interventions with this population.

The authors have not supplied their declaration of competing interest.