Topical medication utilization and health resources consumption in adult patients affected by psoriasis: findings from the analysis of administrative databases of local health units

AIM The objectives of this study were to: 1) analyze the drug utilization pattern among adult psoriasis patients who were newly prescribed with topical medication; and 2) assess their adherence to topical therapy and the possibility of switching to other strategies in the treatment process. METHODS An observational retrospective analysis was conducted based on administrative databases of two Italian local health units. All adult subjects who were diagnosed with psoriasis or who were newly prescribed for topical medication with at least one prescription between January 1, 2010, and December 31, 2014, were screened. Only patients who were "non-occasional users of topical drugs" (if they had at least two prescriptions of topical drugs in a time space of 2 years) were considered for the first and second objectives in the analysis. The date of the first prescription of topical agents was identified as the index date (ID), which was then followed for all time available from ID (follow-up period). The adherence to therapy was assessed on the basis of cycles of treatment covered in the 6 months before the end of the follow-up period. The mean health care costs in patients who switched to disease-modifying antirheumatic drugs (DMARDs) or biologics after the ID were evaluated. RESULTS A total of 17,860 patients with psoriasis who were newly prescribed for topical medication were identified. A total of 2,477 were identified as "non-occasional users of topical drugs", of whom 70.2% had a prescription for a topical fixed combination regimen at ID. Around 19% adhered to their medication, whereas 6% switched to other options of psoriasis treatment. Multivariable logistic regression model shows that patients on fixed combination treatment were less likely to be non-adherent to treatment and less likely to switch to other treatments. The annual mean pharmaceutical costs were €567.70 and €10,606.10 for patients who switched to DMARDs and biologics, respectively. CONCLUSION Our findings show that the use of fixed combination topical treatment can lead to improve the likelihood of patients being adherent to treatment and can decrease the likelihood of switching the treatment to DMARDs or biologics.