title: Implications of lower risk thresholds for statin treatment in primary prevention: analysis of CPRD and simulation modelling of annual cholesterol monitoring.
abstract: OBJECTIVE
  To estimate numbers affected by a recent change in UK guidelines for statin use in primary prevention of cardiovascular disease.
  
  
  METHODS
  We modelled cholesterol ratio over time using a sample of 45,151 men (≥40years) and 36,168 women (≥55years) in 2006, without statin treatment or previous cardiovascular disease, from the Clinical Practice Research Datalink. Using simulation methods, we estimated numbers indicated for new statin treatment, if cholesterol was measured annually and used in the QRISK2 CVD risk calculator, using the previous 20% and newly recommended 10% thresholds.
  
  
  RESULTS
  We estimate that 58% of men and 55% of women would be indicated for treatment by five years and 71% of men and 73% of women by ten years using the 20% threshold. Using the proposed threshold of 10%, 84% of men and 90% of women would be indicated for treatment by 5years and 92% of men and 98% of women by ten years.
  
  
  CONCLUSIONS
  The proposed change of risk threshold from 20% to 10% would result in the substantial majority of those recommended for cholesterol testing being indicated for statin treatment. Implications depend on the value of statins in those at low to medium risk, and whether there are harms.
authors.affiliation: Nuffield Department of Primary Care Health Sciences, University of Oxford, New Radcliffe House, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, UK. Electronic address: ecm33@cantab.net.
authors.forename: Emily
authors.initials: E
authors.lastname: McFadden
authors.affiliation: Nuffield Department of Primary Care Health Sciences, University of Oxford, New Radcliffe House, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, UK. Electronic address: richard.stevens@phc.ox.ac.uk.
authors.forename: Richard
authors.initials: R
authors.lastname: Stevens
authors.affiliation: Faculty of Health Sciences and Medicine, Bond University, Queensland 4229, Australia. Electronic address: pglaszio@bond.edu.au.
authors.forename: Paul
authors.initials: P
authors.lastname: Glasziou
authors.affiliation: Nuffield Department of Primary Care Health Sciences, University of Oxford, New Radcliffe House, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, UK. Electronic address: rafael.perera@phc.ox.ac.uk.
authors.forename: Rafael
authors.initials: R
authors.lastname: Perera
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000517:prevention & control*; D008078:Cholesterol, LDL / Q000097:blood*; D015897:Comorbidity; D003198:Computer Simulation; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000592:standards*; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D011322:Primary Prevention / Q000379:methods / Q000592:standards*; D018570:Risk Assessment / Q000379:methods / Q000706:statistics & numerical data; D012907:Smoking / Q000453:epidemiology; D006113:United Kingdom
chemical_list: D008078:Cholesterol, LDL; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors
keywords: Cardiovascular disease; Cholesterol; Epidemiological monitoring; Hydroxymethylglutaryl-CoA reductase inhibitors; Primary health care