title: Regional Differences in the Prescription of Biologics for Psoriasis in Sweden: A Register-Based Study of 4168 Patients.
abstract: BACKGROUND
  Observational studies suggest an inequitable prescription of biologics in psoriasis care, which may be attributed to geographical differences in treatment access. Sweden regularly ranks high in international comparisons of equitable healthcare, and is, in connection with established national registries, an ideal country to investigate potential inequitable access.
  
  
  OBJECTIVE
  The aim was to determine whether the opportunity for patients to receive biologics depends on where they receive care.
  
  
  METHODS
  Biologic-naïve patients enrolled in the Swedish National Register for Systemic Treatment of Psoriasis (PsoReg) from 2008 to 2015 (n = 4168) were included. The association between the likelihood of initiating a biologic and the region where patients received care was analyzed. The strength of the association was adjusted for patient and clinical characteristics, as well as disease severity using logistic regression analysis. The proportion of patients that switched to a biologic (switch rate) and the probability of switch to a biologic was calculated in 2-year periods.
  
  
  RESULTS
  The national switch rate increased marginally over time from 9.7 to 11.0%, though the uptake varied across regions. Adjusted odds ratios for at least one region were significantly different from the reference region in every 2-year period. During the latest period (2014-2015), the average patient in the lowest prescribing region was nearly 2.5 times less likely to switch as a similar patient in the highest prescribing region.
  
  
  CONCLUSIONS
  Geographical differences in biologics prescription persist after adjusting for patient characteristics and disease severity. The Swedish example calls for further improvements in delivering equitable psoriasis care.
authors.affiliation: The Swedish Institute for Health Economics (IHE), Lund, Sweden.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Calara
authors.affiliation: The Swedish Institute for Health Economics (IHE), Lund, Sweden.
authors.forename: Rikard
authors.initials: R
authors.lastname: Althin
authors.affiliation: The Swedish Institute for Health Economics (IHE), Lund, Sweden.|Department of Clinical Sciences, Malmö, Lund University, Lund, Sweden.
authors.forename: Katarina Steen
authors.initials: KS
authors.lastname: Carlsson
authors.affiliation: Department of Public Health and Clinical Medicine, Dermatology, Umeå University, 901 87, Umeå, Sweden. marcus.schmitt-egenolf@umu.se.
authors.forename: Marcus
authors.identifier: http://orcid.org/0000-0002-3858-8474
authors.initials: M
authors.lastname: Schmitt-Egenolf
mesh_terms: D000328:Adult; D000368:Aged; D011307:Drug Prescriptions; D057915:Drug Substitution / Q000639:trends*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology*; D012042:Registries; D013548:Sweden / Q000453:epidemiology