Psoriasis and obesity in French children: a case-control, multicentre study.

Background: Obesity is more common in adults with psoriasis than in the general population, but there is a lack of data available regarding this association in children.

Objectives: To evaluate whether obesity was more common in French children with psoriasis of any clinical type or severity.

Methods: A multicentre case-control study was performed in 23 French dermatology centres. Children without chronic or genetic inflammatory disease were selected as controls and matched for age, sex and dermatology centre. We used three weight cut-off categories to compare the two groups: overweight, overweight with abdominal obesity and overweight with obesity according to the French Health Authority guidelines.

Results: A total of 261 children with psoriasis were included. The mean age was 9.8 years, 126 were boys and 135 were girls. Overall, 42.5% of these children had plaque psoriasis and 32.2% had severe psoriasis. There was no difference between the psoriasis and control groups when the frequency of children who were overweight was compared (20·7% in psoriasis group vs. 17·1% in control group; P = 0·18). Overweight with abdominal obesity including obesity (18·4% vs. 10·4%; P = 0·009) and obesity alone (10·0% vs. 3·1%; P = 0·001) were more common in the psoriasis group.

Conclusions: This study shows that being overweight with abdominal obesity and being obese is more common in children with psoriasis than in controls. The risk factors are the same as those that affect the French general population, i.e. female sex and having a parent who was overweight. The severity and clinical type of psoriasis do not affect overweight and obesity.