Study Identifies Contributing Factors to Systemic Treatment Non-Adherence in Psoriasis

Samantha DiGrande

The Psoriasis Stratification to Optimize Relevant Therapy (PSORT) study assessed real-world levels of self-reported non-adherence to traditional systemic and biologic therapies used for psoriasis, and evaluated psychological and biomedical factors associated with non-adherence using multivariable analyses.

Conventional systemic and biologic therapies are highly effective in the treatment of moderate to severe psoriasis; however, treatment effectiveness is much lower in routine clinical practice than in clinical trials. Medication non-adherence is a missed opportunity for therapeutic benefit. Although patients go to their doctors for assistance in treating their symptoms, according to the study, approximately half of medications are not taken as prescribed.

This study, Psoriasis Stratification to Optimize Relevant Therapy (PSORT), assessed real-world levels of self-reported non-adherence to traditional systemic and biologic therapies used for psoriasis, and evaluated psychological and biomedical factors associated with non-adherence using multivariable analyses. Researchers defined non-adherence as either being intentional, in which patients knowingly make the decision not to follow the prescribed medication regimen, or unintentional, such as forgetting to take the medication. Of the 811 patients included in the study, 617 self-administered systemic therapy, and 22.4% were classified as non-adherent (12% intentionally, 10.9% unintentionally).

In the traditional systemic treatment group, (35.3%; n = 286), methotrexate was the most common treatment product (52%; n = 141). In the biologic treatement group, (64.7%, n = 525) adalimumab was the most common prescribed biologic (52.5%, n= 258), followed by ustekinumab (32.6%; n = 160) and etanercept (14.9%; n = 73). A significant proportion of patients using self-administered oral conventional systemic or subcutaneous biologic therapies (etanercept, adalimumab) were classified as non-adherent (22.4%); 12% were classified as intentionally and 10.9% were classified as unintentionally non-adherent.

The study reports that the multivariable model showed that being on a conventional systemic (odds ratio [OR], 4.34; 95% CI, 2.38-7.91), having strong medication concerns (OR, 1.92; 95% CI, 1.09-3.39), having a weaker routine or habit for taking systemic therapy (OR, 0.94; 95% CI, 0.91-0.97), a longer treatment duration (OR, 1.04; 95% CI, 1.02-1.06) and a younger age (OR, 0.97; 95% CI, 0.95-0.99), were associated with being classified as overall non-adherent.

The researchers concluded that a significant number of patients with psoriasis who were prescribed self-administered systemic therapies reported both intentional and unintentional non-adherence with their treatment regimen. This study emphasizes the need to assess adherence when determining factors that could be influencing treatment response, rather than the prescribed treatment simply being ineffective.