US researchers used information from the Health Improvement Network database to conduct a population-based study examining adults aged 18 to 90 years with psoriasis versus patients without psoriasis.
The study aimed to confirm a link between psoriasis and type 2 diabetes and to determine if patients with diabetes and psoriasis were being prescribed diabetes medication in comparison to those with diabetes but not psoriasis. It matched 108,132 patients with psoriasis with 430,716 without psoriasis and found that the adjusted attributable risk of developing type 2 diabetes among 1,000 patients with psoriasis per year is 0.9 extra cases overall, 0.7 cases in those with mild psoriasis and 3.0 in those with severe psoriasis.
Patients with mild psoriasis recorded no difference in the use of oral hypoglycaemic agents or insulin, while those with severe disease were more likely to be on oral hypoglycaemic agents and had a greater trend towards being on insulin. The authors conclude that patients with severe psoriasis have a higher risk of type 2 diabetes than those with a mild form of the disease.
Azfar RS et al. Arch Dermatol 2012; 148(6): 761-2