Sustained remission remains elusive for many PsA patients

Many patients with psoriatic arthritis (PsA) have failed to achieve remission despite treatment with various biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs), reveals a nationwide registry study in Sweden.

In addition, nearly half of the patients in the study have never achieved sustained remission (SR).

The study included 4,669 patients with PsA initiating b/tsDMARDs who were registered in the Swedish Rheumatology Quality Register (SRQ) from April 1999 to December 2019. The authors obtained data on disease/treatment characteristics at first b/tsDMARD (baseline) initiation and all subsequent visits.

Remission was defined as Disease Activity Score in 28 joints based on C-reactive protein (DAS28-CRP) ≤2.6, Disease Activity Index for Psoriatic Arthritis in 28 joints (DAPSA28) ≤4, or the physician global assessment of disease activity (PGA) on a scale of 0 to 4 (remission=0). 

Additionally, SR was defined by the said criteria persisting during ≥2 consecutive visits for ≥6 months. The authors used logistic regression analysis to explore the baseline predictors of SR.

Data on a total of 48,773 visits were analysed. Of the patients, 81 percent achieved DAS28-CRP remission ever, while 54 percent achieved SR at least once. The respective percentages were 46 percent and 24 percent with DAPSA28 and 69 percent and 38 percent with PGA for ever reaching remission and SR.

Male sex positively predicted attainment of SR when measured by DAPSA28 and PGA, but not by DAS28-CRP. Based on all three remission criteria, fewer swollen joints at baseline also predicted SR.

“Fewer swollen joints at first b/tsDMARD initiation increases the likelihood of SR, regardless of remission criteria used,” the authors said. “There was still a sex difference when measured with DAPSA28 and PGA, with men being more likely to reach SR.”