Increased overall drug utilization in patients with psoriasis: a case–control study based on Dutch general practitioner data

• Published in: British journal of dermatology (1951) Vol. 176; no. 3; pp. 634 - 642
• Main Authors: Dowlatshahi, E.A., Hollestein, L.M., Herings, R.M.C., Nijsten, T., Wakkee, M.
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.03.2017
• Subjects: Case-Control Studies; Chronic Disease; Dermatologic Agents - therapeutic use; Drug Utilization - statistics & numerical data; Female; General Practice - statistics & numerical data; Health risk assessment; Humans; Laxatives; Male; Middle Aged; Netherlands - epidemiology; Population studies; Prescription drugs; Psoriasis; Psoriasis - drug therapy; Psoriasis - epidemiology
• ISSN: 0007-0963; 1365-2133
• DOI: 10.1111/bjd.14754

Summary Background Medication use in patients with psoriasis has been studied mostly in the context of psoriasis comorbidities. Objectives To investigate detailed drug utilization in patients with psoriasis compared with controls in a population‐based sample. Methods This was a case–control study based on drug prescriptions derived from a Dutch general practitioner database where patients with psoriasis and controls without psoriasis were matched 1 : 1 for age, sex, general practitioner and duration of follow‐up, between 2002 and 2012. We calculated Mantel–Haenszel odds ratios (ORs) and 95% confidence intervals (CIs) for all therapeutic groups and chemical substances. Results In total 17 627 patients with psoriasis and 17 627 controls were followed for > 4 years. Overall 20% of patients with psoriasis received no psoriasis treatment and 8% had moderate‐to‐severe disease. During the entire follow‐up a mean of nine unique drugs were prescribed in patients with psoriasis; this was significantly higher than in controls (mean of seven). Drug use did not peak around the date of diagnosis for psoriasis, but remained constant over time. All of the most commonly prescribed therapeutic groups were significantly more often prescribed in patients with psoriasis than in controls. These included drugs associated with psoriasis symptoms and treatment (OR 2·17, 95% CI 2·07–2·28 and OR 22, 95% CI 21–25, respectively), drugs related to psoriasis comorbidities (1·46, 95% CI 1·39–1·53) and a proportion of drugs that were a priori not expected to be increased in patients with psoriasis, such as nasal preparations and laxatives. Conclusions Patients with psoriasis received more prescriptions for all drugs, regardless of associated comorbidities. This overall increased use of drugs suggests an increased healthcare utilization in patients with psoriasis identified in routine databases. What's already known about this topic? Patients with psoriasis use more health resources than people without psoriasis. Medication use in psoriasis has been studied mostly in the context of psoriasis comorbidities. What does this study add? This is the first large population‐based study to give an overview of the entire spectrum of drug use in patients with psoriasis compared with controls, during a long follow‐up period. The findings suggest increased healthcare utilization among patients with psoriasis. Linked Comment: Yiu. Br J Dermatol 2017; 176:566–567. Plain language summary available online