A new study has found that there seems to be a genetic link between psoriasis, type 2 diabetes or T2DM and obesity. Previous research have shown links between the three, but Ann Lonnberg and her team have added to this knowledge by using twins in their population-based, cross-sectional study.
Lonnberg, MD, of the University of Copenhagen in Denmark and her colleagues examined data from 34,781 twins registered in the Danish Twin Registry. Information on height, weight, diagnoses of psoriasis and diabetes, lifestyle and environmental factors were collected. The researchers then concentrated on 720 twin pairs in which one twin had psoriasis and the other did not.
The team found that the existence of psoriasis in persons with T2DM was nearly twice as high as in those without. In twins where one of them had psoriasis and the other did not, the twin with psoriasis was observed to be more obese. The risk for obesity was also almost twice as high for the twin with psoriasis. However, the risk for T2DM was the same in both twins.
This same study found a small but significant genetic correlation between psoriasis and body mass index (BMI), but not between psoriasis and T2DM. The environmental correlation between psoriasis and BMI was insignificant.
According to the study,
Psoriasis was significantly associated with type 2 diabetes mellitus and obesity in this nationwide study of Danish twins, even after adjustment for confounders. Furthermore, this study is the first, to our knowledge, to determine the contribution of genetic and environmental factors to the interaction between obesity, type 2 diabetes mellitus, and psoriasis.
Given the results that Lonnberg and her team have come up with, Joel Gelfand, MD of the University of Pennsylvania Perelman School of Medicine in Philadephia, recommends that psoriasis patients be screened for diabetes. “The weight of evidence linking psoriasis to cardiometabolic disease continues to increase, tipping the scale toward changing clinical practice in dermatology,” Gelfand writes in an editorial. “Dermatologists have the opportunity to educate patients with psoriasis and initiate appropriate screenings (or refer them to primary care physicians),which can result in better health outcomes through evidence-based interventions.”
The study was published in JAMA Dermatology.