Biologic therapies and psoriatic arthritis risk in psoriasis: A systematic review and meta‐analysis

BACKGROUND: Whether biologic therapies can potentially reduce the risk of transition to psoriatic arthritis (PsA) remains uncertain. OBJECTIVES: To evaluate whether biologic therapy is associated with a reduced risk of incident PsA among patients with psoriasis. METHODS: The primary and secondary endpoints were the incidence of PsA among patients with psoriasis and the associated hazard ratio (HR) for PsA development. Pooled relative risk (RR) and HR estimates were calculated using random effect models. RESULTS: Eighteen studies were included, involving conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), biologic DMARDS (bDMARDs), phototherapy, topical therapy and no therapy. The primary analysis showed no significant difference between bDMARDs and non-biologic therapies in preventing PsA (RR: 0.71, 95% CI: 0.34, 1.51; HR: 0.71, 95% CI: 0.44, 1.17). Subgroup analyses by data source showed that a lower risk of incident PsA with bDMARDs was observed in clinical cohort studies (RR: 0.31, 95% CI: 0.11, 0.87), but not in registry studies (RR: 1.03, 95% CI: 0.44, 2.40). In sensitivity analyses excluding one influential study, a lower observed risk of PsA was identified among patients receiving bDMARDs. Among studies reporting dichotomous outcomes, treatment with interleukin-17 inhibitors (IL-17i), IL-23i or IL-12/-23i was associated with a lower risk of PsA compared with tumour necrosis factor inhibitors (TNFi). IL-17i also showed a numerically lower risk than IL-12/-23i. Among studies reporting continuous outcomes, IL-23i exposure was associated with a lower risk of PsA compared with IL-17i or TNFi. Similarly, IL-17i or IL-12/-23i was associated with a lower risk of PsA relative to TNFi. CONCLUSIONS: Biologic agent was not associated with a reduced overall risk of PsA in psoriasis, but subgroup analyses by data source and biologic class suggested potential risk modification. These findings are hypothesis-generating and require confirmation in prospective studies and randomized trials.