A new meta-analysis comprising more than 7 million people suggests it may be time to add inflammatory bowel disease (IBD) to the list of comorbidities associated with psoriasis.

The findings appear inJAMA Dermatology.

The meta-analysis included five case-control or cross-sectional studies with 1,826,677 individuals. These studies found that patients with psoriasis had 1.70-fold increased odds of Crohn’s disease and 1.75-fold increased odds for ulcerative colitis. Four cohort studies of 5,967,410 individuals included in the meta-analysis found patients with psoriasis had a 2.53-fold increased risk of developing Crohn’s disease and a 1.71-fold increased risk of developing ulcerative colitis.

“Patients with psoriasis should be informed about the increased risk of IBD,” says study author Yun Fu of Chang Gung Memorial Hospital in Linkou, Taiwan. “Gastroenterology consultation is indicated for patients with psoriasis presenting with bowel symptoms.”