Heart, Lung and Circulation
Research Article|Articles in Press

What is the Statin Possession Ratio Cut-Off Which Identifies Those at Increased Risk Following Acute Coronary Syndrome (ANZACS-QI 68)?

Published:January 12, 2023DOI:


      More optimal dispensing of statins is associated with greater cholesterol lowering; however, it is not known whether this translates to improved outcomes following acute coronary syndrome (ACS). The aim of this study was to assess the association between various levels of statin adherence and outcomes following ACS.


      Patients hospitalised with ACS who underwent coronary angiography between 2014–2018 were identified from the All New Zealand ACS Quality Improvement (ANZACS-QI) registry. Medication possession ratio (MPR) was used to assess statin adherence and calculated over 1 year post-discharge using linked pharmaceutical dispensing datasets. Optimal, adequate and suboptimal adherence was defined as an MPR of ≥1.0, 0.8–0.99 and 0–0.79, respectively. A combined outcome of all-cause mortality and rehospitalisation for atherosclerotic disease was identified from 1 year post-discharge through September 2021. Cox proportional hazard models were used to adjust for confounding variables.


      Of the 30,452 patients, 68% had optimal adherence, 15% adequate adherence and 16% had suboptimal adherence to statins. Mean follow-up was 3.6 years. Those with suboptimal adherence had a higher adjusted risk of the combined outcome compared with those with optimal adherence (HR 1.18, 95% CI 1.11–1.26). There was no significant difference in adjusted outcome between those with optimal and adequate adherence (HR 0.99, 95% CI 0.92–1.06).


      Suboptimal statin adherence following ACS is associated with an increased risk of mortality and rehospitalisation. An MPR cut-off of 0.8 seems reasonable to identify those at higher risk of cardiovascular events that could benefit the most from interventions to improve statin adherence and is appropriate as a target for quality improvement programs.


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        • Chew D.P.
        • Scott I.A.
        • Cullen L.
        • French J.K.
        • Briffa T.G.
        • Tideman P.A.
        • et al.
        National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand: Australian clinical guidelines for the management of acute coronary syndromes 2016.
        Med J Aust. 2016; 205: 128-133
        • Lam W.Y.
        • Fresco P.
        Medication adherence measures: an overview.
        Biomed Res Int. 2015; 2015: 217047
        • De Vera M.A.
        • Bhole V.
        • Burns L.C.
        • Lacaille D.
        Impact of statin adherence on cardiovascular disease and mortality outcomes: a systematic review.
        Br J Clin Pharmacol. 2014; 78: 684-698
        • Ho P.M.
        • Bryson C.L.
        • Rumsfeld J.S.
        Medication adherence: its importance in cardiovascular outcomes.
        Circulation. 2009; 119: 3028-3035
        • Khalaf K.
        • Johnell K.
        • Austin P.C.
        • Tyden P.
        • Midlov P.
        • Perez-Vicente R.
        • et al.
        Low adherence to statin treatment during the 1st year after an acute myocardial infarction is associated with increased 2nd-year mortality risk—an inverse probability of treatment weighted study on 54 872 patients.
        Eur Heart J Cardiovasc Pharmacother. 2021; 7: 141-147
        • Brown R.
        • Lewsey J.
        • Wild S.
        • Logue J.
        • Welsh P.
        Associations of statin adherence and lipid targets with adverse outcomes in myocardial infarction survivors: a retrospective cohort study.
        BMJ Open. 2021; 11e054893
        • Bryson C.L.
        • Au D.H.
        • Young B.
        • McDonell M.B.
        • Fihn S.D.
        A refill adherence algorithm for multiple short intervals to estimate refill compliance (ReComp).
        Med Care. 2007; 45: 497-504
        • Muniandy A.
        • Lee M.
        • Grey C.
        • Ferrier K.
        • Kerr A.J.
        Demographic differences in the initiation and maintenance of statins in the first year post ACS in New Zealand: a data linkage study (ANZACS-QI 57).
        N Z Med J. 2021; 134: 31-45
        • Kerr A.J.
        • Turaga M.
        • Grey C.
        • Lee M.
        • McLachlan A.
        • Devlin G.
        Initiation and maintenance of statins and aspirin after acute coronary syndromes (ANZACS-QI 11).
        J Prim Health Care. 2016; 8: 238-249
        • Kerr A.
        • Williams M.J.
        • White H.
        • Doughty R.
        • Nunn C.
        • Devlin G.
        • et al.
        The All New Zealand Acute Coronary Syndrome Quality Improvement Programme: implementation, methodology and cohorts (ANZACS-QI 9).
        N Z Med J. 2016; 129: 23-36
        • Kerr A.
        • Exeter D.
        • Hanham G.
        • Grey C.
        • Zhao J.
        • Riddell T.
        • et al.
        Effect of age, gender, ethnicity, socioeconomic status and region on dispensing of CVD secondary prevention medication in New Zealand: the atlas of health care variation CVD cohort (VIEW-1).
        N Z Med J. 2014; 127: 39-69
        • Thygesen K.
        • Alpert J.S.
        • Jaffe A.S.
        • Simoons M.L.
        • Chaitman B.R.
        • White H.D.
        • et al.
        Third universal definition of myocardial infarction.
        Circulation. 2012; 126: 2020-2035
        • Anderson J.L.
        • Adams C.D.
        • Antman E.M.
        • Bridges C.R.
        • Califf R.M.
        • Casey Jr., D.E.
        • et al.
        ACC/AHA 2007 guidelines for the management of patients with unstable angina/non ST-elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the Management of Patients With Unstable Angina/Non ST-Elevation Myocardial Infarction): developed in collaboration with the American College of Emergency Physicians, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons: endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation and the Society for Academic Emergency Medicine.
        Circulation. 2007; 116: e148-e304
      1. Health Information Standards Organisation. HISO 10001:2017. Ethnicity data protocols. Wellington: Ministry of Health; 2017 September 2017.
        • Atkinson J.
        • Salmond C.
        • Crampton P.
        NZDep2013 Index of Deprivation. Dunedin: University of Otago; 2014.
        • Granger C.B.
        • Goldberg R.J.
        • Dabbous O.
        • Pieper K.S.
        • Eagle K.A.
        • Cannon C.P.
        • et al.
        Predictors of hospital mortality in the global registry of acute coronary events.
        Arch Intern Med. 2003; 163: 2345-2353
        • Quan H.
        • Li B.
        • Couris C.M.
        • Fushimi K.
        • Graham P.
        • Hider P.
        • et al.
        Updating and validating the Charlson comorbidity index and score for risk adjustment in hospital discharge abstracts using data from 6 countries.
        Am J Epidemiol. 2011; 173: 676-682
        • Stone N.J.
        • Robinson J.G.
        • Lichtenstein A.H.
        • Bairey Merz C.N.
        • Blum C.B.
        • Eckel R.H.
        • et al.
        2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.
        Circulation. 2014; 129: S1-S45
        • Gellad W.F.
        • Thorpe C.T.
        • Steiner J.F.
        • Voils C.I.
        The myths of medication adherence.
        Pharmacoepidemiol Drug Saf. 2017; 26: 1437-1441
        • Karve S.
        • Cleves M.A.
        • Helm M.
        • Hudson T.J.
        • West D.S.
        • Martin B.C.
        Good and poor adherence: optimal cut-point for adherence measures using administrative claims data.
        Curr Med Res Opin. 2009; 25: 2303-2310
        • Awad K.
        • Serban M.C.
        • Penson P.
        • Mikhailidis D.P.
        • Toth P.P.
        • Jones S.R.
        • et al.
        Effects of morning vs evening statin administration on lipid profile: a systematic review and meta-analysis.
        J Clin Lipidol. 2017; 11: 972-985.e9
        • Watanabe J.H.
        • Bounthavong M.
        • Chen T.
        Revisiting the medication possession ratio threshold for adherence in lipid management.
        Curr Med Res Opin. 2013; 29: 175-180
        • Simpson S.H.
        • Eurich D.T.
        • Majumdar S.R.
        • Padwal R.S.
        • Tsuyuki R.T.
        • Varney J.
        • et al.
        A meta-analysis of the association between adherence to drug therapy and mortality.
        BMJ. 2006; 333: 15
        • Rasmussen J.N.
        • Chong A.
        • Alter D.A.
        Relationship between adherence to evidence-based pharmacotherapy and long-term mortality after acute myocardial infarction.
        JAMA. 2007; 297: 177-186
        • Serban M.C.
        • Colantonio L.D.
        • Manthripragada A.D.
        • Monda K.L.
        • Bittner V.A.
        • Banach M.
        • et al.
        Statin intolerance and risk of coronary heart events and all-cause mortality following myocardial infarction.
        J Am Coll Cardiol. 2017; 69: 1386-1395
        • Kerr A.
        • Shuker C.
        • Devlin G.
        Transparency in the year of COVID-19 means tracking and publishing performance in the whole health system: progress on the public reporting of acute coronary syndrome data in New Zealand.
        N Z Med J. 2020; 133: 113-119
        • Mihaylova B.
        • Emberson J.
        • Blackwell L.
        • Keech A.
        • Simes J.
        • et al.
        • Cholesterol Treatment Trialists’ (CTT) Collaborators
        The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials.
        Lancet. 2012; 380: 581-590
        • Ryan R.
        • Santesso N.
        • Lowe D.
        • Hill S.
        • Grimshaw J.
        • Prictor M.
        • et al.
        Interventions to improve safe and effective medicines use by consumers: an overview of systematic reviews.
        Cochrane Database Syst Rev. 2014; CD007768
        • Ye X.
        • Gross C.R.
        • Schommer J.
        • Cline R.
        • St Peter W.L.
        Association between copayment and adherence to statin treatment initiated after coronary heart disease hospitalization: a longitudinal, retrospective, cohort study.
        Clin Ther. 2007; 29: 2748-2757
        • Vollmer W.M.
        • Owen-Smith A.A.
        • Tom J.O.
        • Laws R.
        • Ditmer D.G.
        • Smith D.H.
        • et al.
        Improving adherence to cardiovascular disease medications with information technology.
        Am J Manag Care. 2014; 20: SP502-SP510
        • Garofalo R.
        • Kuhns L.M.
        • Hotton A.
        • Johnson A.
        • Muldoon A.
        • Rice D.
        A randomized controlled trial of personalized text message reminders to promote medication adherence among HIV-positive adolescents and young adults.
        AIDS Behav. 2016; 20: 1049-1059
        • Peersen K.
        • Munkhaugen J.
        • Gullestad L.
        • Liodden T.
        • Moum T.
        • Dammen T.
        • et al.
        The role of cardiac rehabilitation in secondary prevention after coronary events.
        Eur J Prev Cardiol. 2017; 24: 1360-1368
        • Taitel M.
        • Jiang J.
        • Rudkin K.
        • Ewing S.
        • Duncan I.
        The impact of pharmacist face-to-face counseling to improve medication adherence among patients initiating statin therapy.
        Patient Prefer Adherence. 2012; 6: 323-329
        • Mach F.
        • Baigent C.
        • Catapano A.L.
        • Koskinas K.C.
        • Casula M.
        • Badimon L.
        • et al.
        2019 ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk.
        Eur Heart J. 2020; 41: 111-188
        • Mbizvo R.M.
        • Alfadhel M.
        • Williams M.J.A.
        • Coffey S.
        • Kerr A.
        • Webster M.
        • et al.
        A contemporary presentation of the incidence and management of spontaneous coronary artery dissection (SCAD) in New Zealand: an ANZACS-QI study.
        Eur Heart J. 2021; 42 (ehab724.1306)