title: Discontinuation and restarting in patients on statin treatment: prospective open cohort study using a primary care database.
abstract: OBJECTIVE
  To estimate rates of discontinuation and restarting of statins, and to identify patient characteristics associated with either discontinuation or restarting.
  
  
  METHODS
  Prospective open cohort study.
  
  
  METHODS
  664 general practices contributing to the Clinical Practice Research Datalink in the United Kingdom. Data extracted in October 2014.
  
  
  METHODS
  Incident statin users aged 25-84 years identified between January 2002 and September 2013. Patients with statin prescriptions divided into two groups: primary prevention and secondary prevention (those already diagnosed with cardiovascular disease). Patients with statin prescriptions in the 12 months before study entry were excluded.
  
  
  METHODS
  Discontinuation of statin treatment (first 90 day gap after the estimated end date of a statin prescription), and restarting statin treatment for those who discontinued (defined as any subsequent prescription between discontinuation and study end).
  
  
  RESULTS
  Of 431 023 patients prescribed statins as primary prevention with a median follow-up time of 137 weeks, 47% (n=204 622) discontinued treatment and 72% (n=147 305) of those who discontinued restarted. Of 139 314 patients prescribed statins as secondary prevention with median follow-up time of 182 weeks, 41% (n=57 791) discontinued treatment and 75% (43 211) of those who discontinued restarted. Younger patients (aged ≤50 years), older patients (≥75 years), women, and patients with chronic liver disease were more likely to discontinue statins and less likely to restart. However, patients in ethnic minority groups, current smokers, and patients with type 1 diabetes were more likely to discontinue treatment but then were more likely to restart, whereas patients with hypertension and type 2 diabetes were less likely to discontinue treatment and more likely to restart if they did discontinue. These results were mainly consistent in the primary prevention and secondary prevention groups.
  
  
  CONCLUSIONS
  Although a large proportion of statin users discontinue, many of them restart. For many patient groups previously considered as "stoppers," the problem of statin treatment "stopping" could be part of the wider issue of poor adherence. Identification of patient groups associated with completely stopping or stop-starting behaviour has positive implications for patients and doctors as well as suggesting areas for future research.
authors.affiliation: Division of Primary Care, University of Nottingham, University Park, Nottingham, NG2 7RD, UK Yana.Vinogradova@nottingham.ac.uk.
authors.forename: Yana
authors.initials: Y
authors.lastname: Vinogradova
authors.affiliation: Division of Primary Care, University of Nottingham, University Park, Nottingham, NG2 7RD, UK.
authors.forename: Carol
authors.initials: C
authors.lastname: Coupland
authors.affiliation: Avon Primary Care Research Collaborative, Bristol Clinical Commissioning Group, Bristol, UK University of Bristol, Bristol, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Brindle
authors.affiliation: Division of Primary Care, University of Nottingham, University Park, Nottingham, NG2 7RD, UK.
authors.forename: Julia
authors.initials: J
authors.lastname: Hippisley-Cox
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D008297:Male; D054539:Medication Therapy Management / Q000706:statistics & numerical data; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011320:Primary Health Care / Q000379:methods / Q000706:statistics & numerical data; D011322:Primary Prevention / Q000379:methods / Q000706:statistics & numerical data; D011446:Prospective Studies; D055502:Secondary Prevention / Q000379:methods / Q000706:statistics & numerical data; D006113:United Kingdom / Q000453:epidemiology; D016903:Drug Monitoring
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors