Medication adherence among patients with psoriasis on traditional systemic and biologics treatment

Funding sources: none. Conflicts of interest: none declared. Dear Editor, The World Health Organization defines medication adherence as ‘the extent to which a patient's behaviour in taking their medication corresponds to agreed recommendations by their healthcare provider’.1 Up to 25% of patients, across all medical conditions, do not take their medication.2 Patients with poor adherence have worse outcomes and higher healthcare costs.3,4 Suboptimal adherence has been reported in psoriasis. Adherence is better for biologics and traditional systemic therapies than for topical agents and phototherapy.5 Systemic treatments for psoriasis can be expensive and an increased understanding of therapy adherence would be beneficial. The aims of our study were to measure adherence to systemic treatments in moderate‐to‐severe psoriasis and to identify predictors of adherence. The study was approved by the medical research and ethics committee of St Vincent's University Hospital. All patients had moderate‐to‐severe psoriasis and were receiving systemic therapy. After giving informed consent, patients completed questionnaires including demographics, Patient Global Assessment (PtGA), Morisky Medication Adherence Scale (MMAS) modified for psoriasis, Hospital Anxiety and Depression Scale (HADS), Dermatology Life Quality Index (DLQI), Revised Illness Perception Questionnaire (IPQ‐R) and Beliefs about Medications Questionnaire (BMQ). Data were analysed using SPSS (IBM, Armonk, NY, U.S.A.), using the χ2‐test or Spearman's correlation.