title: Estimating the prevalence and incidence of type 2 diabetes using population level pharmacy claims data: a cross-sectional study.
abstract: OBJECTIVE
  To estimate the prevalence and incidence of type 2 diabetes using a national pharmacy claims database.
  
  
  METHODS
  We used data from the Health Service Executive-Primary Care Reimbursement Service database in Ireland for this cross-sectional study. Prevalent cases of type 2 diabetes were individuals using an oral hypoglycemic agent, irrespective of insulin use, in 2012. Incident cases were individuals using an oral hypoglycemic agent in 2012 who had not used one in the past. Population level estimates were calculated and stratified by age and sex.
  
  
  RESULTS
  In 2012, there were 114 957 prevalent cases of type 2 diabetes giving a population prevalence of 2.51% (95% CI 2.49% to 2.52%). Among adults (≥15yrs), this was 3.16% (95% CI 3.15% to 3.18%). The highest prevalence was in those aged 70+ years (12.1%). 21 574 people developed type 2 diabetes in 2012 giving an overall incidence of 0.48% (95% CI 0.48% to 0.49%). In adults, this was 0.60% (95% CI 0.60% to 0.61%). Incidence rose with age to a maximum of 2.08% (95% CI 2.02% to 2.15%) in people aged 65-69 years. Men had a higher prevalence (2.96% vs 2.04%) and incidence (0.54% vs 0.41%) of type 2 diabetes than women.
  
  
  CONCLUSIONS
  Pharmacy claims data allow estimates of objectively defined type 2 diabetes at the population level using up-to-date data. These estimates can be generated quickly to inform health service planning or to evaluate the impact of population level interventions.
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, Cork, Ireland; Department of Non-communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Sarah-Jo
authors.initials: SJ
authors.lastname: Sinnott
authors.affiliation: Department of Epidemiology and Public Health , University College Cork , Cork , Ireland.
authors.forename: Sheena
authors.initials: S
authors.lastname: McHugh
authors.affiliation: School of Dentistry , University of Leeds , Leeds , UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Whelton
authors.affiliation: Department of Sociology, School of Social Sciences and Philosophy, Trinity College Dublin, Dublin, Ireland; Economic and Social Research Institute, Dublin, Ireland.
authors.forename: Richard
authors.initials: R
authors.lastname: Layte
authors.affiliation: Economic and Social Research Institute , Dublin , Ireland.
authors.forename: Steve
authors.initials: S
authors.lastname: Barron
authors.affiliation: Department of Epidemiology and Public Health , University College Cork , Cork , Ireland.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Kearney
keywords: Administrative Data; Epidemiology; Incidence; Type 2