As anyone living with a chronic condition knows, getting a proper and timely diagnosis and finding effective treatment can be very difficult without the proper physician. However, those with psoriatic spondylitis can face an even longer and more complex process. Beginning with a diagnosis of psoriasis, 30% of patients will have their condition develop into psoriatic arthritis (PsA) – a combination of the scaly rashes of psoriasis, and the joint inflammation of peripheral arthritis. PsA patients then have a 20% chance of developing psoriatic spondylitis, in which the inflammation and arthritis reach the spine.
A recent study published in the Journal of Dermatology sought to examine the progression of psoriasis to psoriatic spondylitis, examine the impact of psoriasis on the severity and manifestation of axial (spinal) symptoms, and identify factors that impact the efficacy of biologic medications.
The study included 2,116 individuals from Western Japan with a clinical diagnosis of psoriasis. Of these patients, 285 (13.5%) also had a diagnosis of PsA, with 69.8% of these PsA patients experiencing psoriatic skin manifestations before the onset of arthritis with a median time of seven years in between. Only 17.2% had both skin and joint symptoms appear simultaneously, and just 2.5% experienced arthritis before psoriasis. After analyzing the data, it was found that patients with a more severe skin condition were found to be significantly younger and had higher rates of spinal arthritis (psoriatic spondylitis.)
Treatment effectiveness was also investigated in the study. In total, 157 patients were prescribed TNF inhibitor medications. 105 patients continued these medications, 47 discontinued them, and 5 were not available for a follow up. Multivariate analysis seems to indicate that age may have played a role in the continuation of this treatment as those who discontinued TNFi treatment were both significantly older than those who continued, and experienced the onset of joint manifestations later.
The study concluded that, “patients with PsA and severe skin manifestations have earlier onset and axial disease [spinal involvement, constituting psoriatic spondylitis], which seriously impacts quality of life. Anti‐TNF‐α antibodies were generally effective enough to continue but less so in patients aged over 50 years.”
References and Further Reading:
Tsuruta N, Narisawa Y, Imafuku S, et al. Cross-sectional multicenter observational study of psoriatic arthritis in Japanese patients: relationship between skin and joint symptoms and results of treatment with tumor necrosis factor-α inhibitors [published online January 10, 2019]. J Dermatol. doi: 10.1111/1346-8138.14745
Axial disease more common in psoriatic arthritis with acute skin manifestations