Modifiable Risk Factors Associated With Transition From Psoriasis to Psoriatic Arthritis

Psoriatic arthritis (PsA) occurs in approximately one-third of patients with psoriasis, but it may be possible to modify some lifestyle and environmental factors to reduce the risk of patients transitioning from psoriasis to PsA, according to research published in Journal of the American Academy of Dermatology.

PsA causes pain, swelling, and joint stiffness, and it is associated with impaired quality of life, a greater risk of comorbidities, and higher health care expenditures. The underlying events that cause the transition to PsA are not well understood, but current thought is that heredity and the environment both play a role.

“…determining the modifiable factors associated with transition to PsA among patients with psoriasis may provide a unique opportunity for early prevention and deepen our understanding of the etiology of PsA as well,” the authors explained.

The researchers conducted a systematic search of PubMed, EMBASE, and Cochrane Library for observational studies reporting lifestyle or environmental factors for PsA onset in patients with psoriasis. The included 16 studies in their analysis. The studies originated from the United Kingdom (n = 6), Canada (n = 4), the United States (n = 4), Japan (n = 1), and Singapore (n = 1) and they included 322,967 patients.

Nine of the studies assessed the association between smoking and PsA. There were 8 studies on alcohol consumption in patients with psoriasis. Eight studies investigated the risk of PsA onset by body mass index (BMI). A total of 5 studies analyzed physical trauma and the presence of PsA.

The meta-analysis of BMI found a dose-dependent increase in the risk of developing PsA for patients with psoriasis. The risk increased 75% for patients with obesity. Despite the potential causal association between PsA and obesity, “the underlining mechanisms are not completely understood,” the authors wrote. They conjectured that chronic low-grade inflammation status in patients with obesity represents an increase in inflammatory cytokines and an alternation in adipokines, which might lead to the development of PsA in predisposed individuals.

The association between smoking and risk of PsA among patients with psoriaris remains unclear due to severely conflicting findings. One case-control study found a protective relationship, but more recently updated research using the same database showed smoking status was unrelated to PsA risk. However, another study using a large cohort of women found an elevated risk. The authors determined there was no association between smoking status (whether patients had ever smoked, currently smoked, or were past smokers) and the risk of developing PsA.

The authors did note a significant increase in the risk of developing PsA in patients with psoriasis who had had experienced traumatic injury. Individuals with psoriasis who are exposed to physical trauma, such as fracture, may transition from psoriasis to PsA.

The researchers did note their findings require caution since they were interpreting evidence from observational studies, which can be more biased than randomized controlled trials. In addition, not all the studies adjusted enough for potential confounders.

The results of the study highlight a need to “strengthen public health to promote awareness and endeavor to reduce the risk of transition to PsA in psoriasis patients, and furthermore deepen our understanding of the etiology of PsA,” the authors concluded.

Reference

Xie W, Huang H, Deng X, Gao D, Zhang Z. Modifiable lifestyle and environmental factors associated with onset of psoriatic arthritis in patients with psoriasis: a systematic review and meta-analysis of observational studies. J Am Acad Dermatol. Published online August 19, 2020. doi:10.1016/j.jaad.2020.08.060