The Unfavorable Role of Obesity in Psoriatic Disease

Jul 11, 2024

Photo Credit: SIphotography

The association between obesity and psoriatic disease. Smoking, genetics, as well as obesity, all potentially contribute to the development of psoriasis in all age groups.

Smoking, genetics, and obesity are associated with developing psoriasis. During a talk at IFPA 2024, Prof. Ulrich Mrowietz, MD, from the University Medical Center Schleswig-Holstein, in Germany, described the association between obesity and psoriatic disease and potential solutions to address the problem.

The risk for developing psoriasis is higher in people who are obese. A Danish cohort of participants with bariatric surgery (n=12,364) showed a decreased risk for psoriasis (HR 0.52; 95% CI 0.33–0.81), severe psoriasis (HR 0.44; 95% CI 0.23–0.86), and psoriatic arthritis (HR 0.29; 95% CI 0.12–0.71) following gastric bypass surgery. In a similar Swedish study including 1,991 participants with bariatric surgery and 2,018 controls who had obesity with a follow-up of up to 26 years, the risk for developing psoriasis was lower in participants who underwent surgery (HR 0.65; 95% CI 0.47–0.89; P=0.008). Furthermore, a longer duration of obesity at baseline was associated with developing psoriasis independently of surgery (HR 1.28; 95% CI 1.05–1.55; P=0.014). “So obesity, from a medical perspective but from a societal, political, and healthcare perspective, is very important to the risk for getting immune-mediated inflammatory disorders,” said Prof. Mrowietz.

Pediatric Obesity

In a meta-analysis of multiple studies, pediatric psoriasis was significantly associated with overweight (OR 1.58; 95% CI 1.14–2.19; P=0.006) and with obesity (OR 2.45; 95% CI 1.73–3.48; P<0.001). Moderate-to-severe childhood psoriasis was more commonly associated with obesity than mild childhood psoriasis (OR 1.66; 95% CI 1.16–2.37; P=0.005). Furthermore, childhood psoriasis was also associated with higher odds of diabetes, metabolic syndrome, and cardiovascular disease (i.e. ischemic heart disease or heart failure).

Understanding the Link Between Obesity and Psoriasis

Adipocytes are metabolically and immunologically active cells, with immune cell recruitment to adipose tissue leading to chronic inflammation. “Being obese means that adipocytes are more active but it also means that they increase in number,” explained Prof. Mrowietz. “The problem then is that in those patients who are counseled to lose weight the number of adipocytes is not decreased; they will stay the same, so the rebound is more predictable.” Also, obesity leads to an increase in immune cells and interleukins involved in the development of psoriasis, as well as disruption of regulatory T-cell pathways.

Treatment Options for Obesity-Associated Psoriasis

Prof. Mrowietz thinks that GLP-1 receptor agonists such as tirzepatide and semaglutide could be the solution. A case report published in 2023 described resolution of psoriasis (PASI score drop from 12 to 0.2) following 10 months of treatment with semaglutide in a 50-year-old woman with a BMI of 30 kg/m² and with disease refractory to ixekizumab, secukinumab, and guselkumab. However, these results will need to be confirmed in larger studies.

“Obesity is causing psoriasis but psoriasis is not causing obesity, and obesity is an independent risk factor for psoriatic disease,” concluded Prof. Mrowietz. “Management of obesity and its impact is key,” continued Prof. Mrowietz, adding that administration of GLP-1 receptor agonists could be a solution for an integrated approach to treatment.