Can Biologics Prevent PsA in Psoriasis Patients?
Patients with moderate-to-severe plaque psoriasis who were treated with biologics were less likely to develop psoriatic arthritis (PsA) than if they received phototherapy, Italian researchers reported. Among psoriasis patients who were given treatment with biologic agents, the annual incidence rate for PsA was 1.20 (95% CI 0.77-1.89) cases per 100 patients compared with an incidence rate of 2.17 (95% CI 1.53-3.06) per 100 for those treated with phototherapy, according to Paolo Gisondi, MD, of the University Hospital of Verona, and colleagues. In a multivariate analysis that adjusted for numerous factors including age and sex, as well as duration, localization, and severity of psoriasis, the hazard ratio for the development of PsA among patients receiving biologic treatment was 0.27 (95% CI 0.11-0.66, P=0.004), they reported in Annals of the Rheumatic Diseases. Up to one-quarter of individuals with psoriasis eventually develop PsA, often 5 to 10 years after the skin lesions first appear. "The delay between the onset of skin manifestations of psoriasis and joint disease may provide a therapeutic window of clinical opportunity for preventing the progression from psoriasis to PsA," Gisondi's group wrote. To explore the possibility of exploiting that therapeutic window, they conducted a retrospective nonrandomized intervention study of patients seen in the dermatology department at their center between 2012 and 2020. They identified 234 patients who had been treated with a biologic disease-modifying antirheumatic drug (DMARD) for at least 5 years and 230 who had been given at least three courses (with each course consisting of 24 to 32 sessions) narrowband ultraviolet B (UVB) phototherapy. Among the biologics group, 17% received infliximab (Remicade), 7% were given etanercept (Enbrel), 29% received adalimumab (Humira), 21% were taking the interleukin (IL)-12/23 inhibitor ustekinumab (Stelara), and 26% were on the IL-17A inhibitor secukinumab (Cosentyx). Overall follow-up time was a mean of 6.76 years per person. Baseline factors that were associated with the development of PsA included:  Age: 53.7 vs 46.6 years (P<0.001)  Duration of psoriasis: 25.3 vs 22.4 years (P=0.013)  Family history of PsA: 14% vs 7% (P=0.046)  Scalp involvement: 78% vs 66% (P=0.051)  Nail involvement: 55% vs 41% (P=0.032)  No association was seen for BMI or comorbidities such as hypertension and diabetes. Throughout follow-up, 8% of patients in the biologics group and 14% of those in the phototherapy group developed PsA. The most common manifestations were peripheral arthritis in 84%, dactylitis in 20%, enthesitis in 16%, and axial involvement in 6%. On a univariate analysis, factors that were associated with incident PsA were older age, nail and scalp involvement, family history of PsA, psoriasis duration of more than 10 years, and baseline Psoriasis Area and Severity Index. On the fully adjusted multivariable analysis, factors other than biologics treatment that were associated with PsA were age (HR 1.04, 95% CI 1.02-1.07, P<0.001), nail psoriasis (HR 3.15, 95% CI 1.63-6.06, P=0.001), and psoriasis duration of more than 10 years (HR 2.02, 95% CI 1.09-3.76, P=0.026). Psoriasis and PsA are known to share certain pathogenic pathways mediated by tumor necrosis factor (TNF)-, IL-17, and IL-23. "In the present study, we reasoned that biologic DMARDs targeting TNF- or the IL-23/IL-17 axis could attenuate, delay, or prevent the transition from psoriasis to PsA. In contrast, narrow band UVB phototherapy dampens only skin inflammation and is regarded as a specific skin targeted therapy," the investigators wrote. However, factors other than treatment influence the disease trajectory, they noted. Previous research has demonstrated that genetic factors also play a prominent role in determining the progression from psoriasis to PsA. Certain human leukocyte antigen alleles are more common in PsA patients compared with the general population, and polymorphisms of the IL-23 receptor and TNF--induced protein-3 genes are more strongly associated with PsA than with psoriasis alone. Study limitations included its retrospective nonrandomized design. "Future larger prospective and intervention studies are needed to further validate these findings in independent samples," they concluded. Nancy Walsh earned a BA in English literature from Salve Regina College in Newport, R.I.