Vinod Chandran, MBBS, MD, DM, PhD
There have been quite a few papers published in October that have provided further insights into psoriatic arthritis (PsA). Understanding risk factors for developing PsA in patients with psoriasis is of ongoing interest, but there is limited data on the relationship between the severity of psoriasis and the risk of developing PsA especially in the USA population. Using the Optum electronic health records (EHR) database, Merola et al 1 assessed the incidence, prevalence, and predictors of PsA among 114,868 patients with psoriasis between January 1, 2009, and March 31, 2019. The severity of psoriasis was determined by treatment received during the 1 year after psoriasis diagnosis as follows: mild (89.3%) topicals and phototherapy only; moderate (5.5%) nonbiologic systemic therapies (acitretin, apremilast, cyclosporine, methotrexate), and severe (5.2%) biologic therapies (adalimumab, certolizumab pegol, etanercept, golimumab, guselkumab, infliximab, ixekizumab, secukinumab, ustekinumab). They found that the overall incidence of PsA was 2.9 (95% CI 2.9-3.0) events per 100 patient-years of follow up (PY). The incidence (100 PY, 95% CI) by severity was lowest (2.1 [95% CI 2.1-2.1]) in the mild, higher in the moderate (9.9 [95% CI 9.5-10.4]), and highest (17.6 [95% CI 16.9-18.3]) in the severe psoriasis category. The study thus confirms that patients with more severe psoriasis have higher risk of developing PsA.
The effect of treatment of psoriasis on the development of PsA is also have great interest. Recent studies 2 have indicated that biologic treatment of psoriasis may reduce the incidence of PsA. However, Meer et al 3 in a retrospective cohort study using of 1,93,709 patients with psoriasis without PsA in the Optum Insights EHR database report that biologic use was associated with the development of PsA among patients with psoriasis. After propensity score matching, the hazard ratio was 2.14 (95% CI 2.00-2.28) for patients on biologics compared to those on oral therapy or phototherapy. Such studies are influenced by confounding factors ,by indication, and protopathic bias and hence prospective studies are warranted.
Better treatment outcomes are likely if patient priorities are taken into account when choosing a therapy. However, there are few studies addressing this issue. Sumpton et al 4 conducted a discrete choice experiment in patients with PsA in Sydney, Australia, to assess preferences for different attributes of biologics. They identified the following attributes in order of preference: oral route (compared to subcutaneous and intravenous routes), avoiding severe side effects, increasing ability to attend to normal activities, avoiding infections, improvement in enthesitis pain, improvement in psoriasis, increasing chance of remission and improvement in joint pain. Thus, patients valued ease of administration, avoiding side effects, and physical function more when choosing a therapy. With increased availability of treatment choices, developing decision support systems that facilitate shared decision making between patients and clinicians is required to improve care of PsA patients.
Ultrasound is increasingly being used at the point of care in rheumatology, but until now ultrasound was not used as a primary outcome in a clinical trial. In the first randomized, placebo-controlled, phase III study using power Doppler ultrasound (PDUS) D’Agostino et al 5 demonstrated that treatment with secukinumab (dosed according to psoriasis severity) led to statistically significant improvement in synovitis measured using the Global European League Against Rheumatism and Outcome Measures in Rheumatoid Arthritis Clinical Trials Synovitis Score (GLOESS) compared to placebo. Thus, secukinumab, an IL-17A inhibitor, reduces synovitis as detected by ultrasound as well as symptoms and clinical signs of PsA.
References
- Merola JF et al. Incidence and Prevalence of Psoriatic Arthritis in Patients With Psoriasis Stratified by Psoriasis Disease Severity: Retrospective Analysis of a US Electronic Health Records Database. J Am Acad Dermatol. 2021(Sep 18):S0190-9622(21)02494-4.
- Acosta Felquer ML et al. Treating the skin with biologics in patients with psoriasis decreases the incidence of psoriatic arthritis. Ann Rheum Dis. 2021 (Jul 19):annrheumdis-2021-220865.
- Meer E et al. Does biologic therapy impact the development of PsA among patients with psoriasis? Ann Rheum Dis. 2021(Oct 6):annrheumdis-2021-220761.
- Sumpton D et al. Preferences for biologic treatment in patients with psoriatic arthritis: a discrete choice experiment. Arthritis Care Res (Hoboken). 2021(Sep 13):acr.24782
- D'Agostino MA et al. Response to secukinumab on synovitis using power Doppler ultrasound in psoriatic arthritis: 12-week results from a phase III study, ULTIMATE. Rheumatology (Oxford). 2021(Sep 16):keab628.