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Canadian Journal of Cardiology

Primary Care Clinical Volumes, Cholesterol Testing, and Cardiovascular Outcomes

  • Author Footnotes
    ‡ These authors contributed equally to this work.
    Jacob A. Udell
    Correspondence
    Corresponding author: Dr Jacob A. Udell, Peter Munk Cardiac Centre, Toronto General Hospital and Women’s College Hospital, 76 Grenville Street, Toronto, Ontario M5S 1B1, Canada. Tel.: +1-416-351-3732; fax: +1-416-351-3746.
    Footnotes
    ‡ These authors contributed equally to this work.
    Affiliations
    Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada

    ICES, Toronto, Ontario, Canada

    Cardiovascular Division, Department of Medicine, Women’s College Hospital, Toronto, Ontario, Canada

    Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
    Search for articles by this author
  • Author Footnotes
    ‡ These authors contributed equally to this work.
    Arielle R. Brickman
    Footnotes
    ‡ These authors contributed equally to this work.
    Affiliations
    Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada

    ICES, Toronto, Ontario, Canada

    Cardiovascular Division, Department of Medicine, Women’s College Hospital, Toronto, Ontario, Canada
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  • Anna Chu
    Affiliations
    ICES, Toronto, Ontario, Canada
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  • Laura E. Ferreira-Legere
    Affiliations
    ICES, Toronto, Ontario, Canada
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  • Maya S. Sheth
    Affiliations
    Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
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  • Dennis T. Ko
    Affiliations
    ICES, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada

    Schulich Heart Centre, Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
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  • Peter C. Austin
    Affiliations
    ICES, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
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  • Husam Abdel-Qadir
    Affiliations
    Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada

    ICES, Toronto, Ontario, Canada

    Cardiovascular Division, Department of Medicine, Women’s College Hospital, Toronto, Ontario, Canada

    Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
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  • Noah M. Ivers
    Affiliations
    Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada

    ICES, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada

    Department of Family Medicine, Women’s College Hospital, Toronto, Ontario, Canada
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  • R. Sacha Bhatia
    Affiliations
    Women’s College Research Institute, Women’s College Hospital, Toronto, Ontario, Canada

    ICES, Toronto, Ontario, Canada

    Cardiovascular Division, Department of Medicine, Women’s College Hospital, Toronto, Ontario, Canada

    Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
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  • Michael E. Farkouh
    Affiliations
    Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada
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  • Thérèse A. Stukel
    Affiliations
    ICES, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
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  • Jack V. Tu
    Affiliations
    ICES, Toronto, Ontario, Canada

    Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada

    Schulich Heart Centre, Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Search for articles by this author
  • Author Footnotes
    ‡ These authors contributed equally to this work.
Published:December 23, 2022DOI:https://doi.org/10.1016/j.cjca.2022.12.016

      Abstract

      Background

      It is unknown whether the annual number of primary care physician (PCP) unique outpatient assessments, which we refer to as clinical volume, translates into better cardiovascular preventive care. We examined the relationship between PCP outpatient clinical volumes and cholesterol testing and major adverse cardiovascular event rates among guideline-recommended eligible patients.

      Methods

      This was a retrospective cohort study conducted as part of the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) cohort, a population-based cohort of almost all adult residents of Ontario, Canada, followed from 2008 to 2012. For each clinical volume quintile, we compared cholesterol testing and major adverse cardiovascular events, defined as time to first event of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke.

      Results

      The 10,037 PCPs evaluated had an annualized median volume of 2303 clinical encounters (IQR 1292-3680). Among 4,740,380 patients, 84% underwent guideline-concordant cholesterol testing at least once over 5 years, ranging from 73% with the lowest clinical volume quintile physicians to 86% with the highest. After multivariable adjustment, there was a 10.5% relative increase in the probability of cholesterol testing for every doubling of clinical volumes (95% CI 9.7%-11.4%; P < 0.001). Patients treated by the lowest volume quintile physicians had the highest rate of major adverse cardiovascular outcomes (compared with the highest volume quintile physicians: adjusted HR 1.15, 95% CI 1.10-1.21; P < 0.001).

      Conclusions

      Patients of physicians with the lowest clinical volumes received less frequent cholesterol testing and had the highest rate of incident cardiovascular events. Further research investigating the drivers of this relationship is warranted.

      Résumé

      Contexte

      On ne sait pas si un lien peut être établi entre le nombre annuel d’évaluations de patients effectuées en consultation externe (ci-après « volume clinique ») par les médecins de premier recours (MPR) et la qualité des soins cardiovasculaires préventifs. Nous avons examiné la relation entre, d’une part, les volumes cliniques des MPR et, d’autre part, les bilans lipidiques réalisés et les taux de manifestations cardiovasculaires graves chez les patients admissibles selon les lignes directrices.

      Méthodologie

      Il s’agissait d’une étude de cohorte rétrospective menée à partir de la cohorte populationnelle utilisée par l’équipe de recherche sur la santé cardiovasculaire et les soins ambulatoires CANHEART (Cardiovascular Health in Ambulatory Care Research Team), qui comprend presque tous les adultes résidant en Ontario (Canada) ayant fait l’objet d’un suivi entre 2008 et 2012. Pour chaque quintile de volume clinique, nous avons comparé la réalisation de bilans lipidiques et les manifestations cardiovasculaires graves, soit le temps écoulé avant la première manifestation (décès d’origine cardiovasculaire, infarctus du myocarde non mortel ou accident vasculaire cérébral non mortel).

      Résultats

      Au total, les 10 037 MPR évalués avaient rencontré un nombre médian de 2303 patients (intervalle interquartile : 1292 à 3680) par année. Sur les 4 740 380 patients, 84 % se sont fait prescrire un bilan lipidique conforme aux lignes directrices au moins une fois tous les 5 ans, la proportion allant de 73 % pour les médecins du quintile de volume clinique inférieur, à 86 % pour les médecins du quintile supérieur. Après ajustement multivarié, la probabilité qu’un bilan lipidique soit réalisé affichait une hausse relative de 10,5 % chaque fois que le volume clinique doublait (intervalle de confiance [IC] à 95 % : 9,7 à 11,4; p < 0,001). Les patients traités par les médecins du quintile de volume clinique inférieur étaient ceux chez qui on observait le taux de manifestations cardiovasculaires graves le plus élevé, comparativement aux patients des médecins du quintile supérieur (rapport des risques instantanés corrigé : 1,15; IC à 95 % : 1,10 à 1,21; p < 0,001).

      Conclusions

      Les patients dont les médecins avaient les volumes cliniques les moins élevés étaient ceux chez qui les bilans lipidiques étaient moins fréquents et qui affichaient le taux le plus élevé de manifestations cardiovasculaires. D’autres études sont nécessaires pour déterminer les facteurs qui sous-tendent cette relation.

      Graphical abstract

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      References

        • Public Health Agency of Canada
        Heart Disease in Canada.
        (Available at:) (Accessed xxx)
        • Benjamin E.J.
        • Blaha M.J.
        • Chiuve S.E.
        • et al.
        Heart disease and stroke statistics—2017 update: a report from the American Heart Association.
        Circulation. 2017; 135: e146-e603
        • Jollis J.G.
        • Peterson E.D.
        • DeLong E.R.
        • et al.
        The relation between the volume of coronary angioplasty procedures at hospitals treating Medicare beneficiaries and short-term mortality.
        N Engl J Med. 1994; 331: 1625-1629
        • Tu J.V.
        • Austin P.C.
        • Chan B.T.
        Relationship between annual volume of patients treated by admitting physician and mortality after acute myocardial infarction.
        JAMA. 2001; 285: 3116-3122
        • Joynt K.E.
        • Orav E.J.
        • Jha A.K.
        The association between hospital volume and processes, outcomes, and costs of care for congestive heart failure.
        Ann Intern Med. 2011; 154: 94-102
        • Joynt K.E.
        • Orav E.J.
        • Jha A.K.
        Physician volume, specialty, and outcomes of care for patients with heart failure.
        Circ Heart Fail. 2013; 6: 890-897
        • Tung Y.C.
        • Chang G.M.
        • Chien K.L.
        • Tu Y.K.
        The relationships among physician and hospital volume, processes, and outcomes of care for acute myocardial infarction.
        Med Care. 2014; 52: 519-527
        • Kumbhani D.J.
        • Fonarow G.C.
        • Heidenreich P.A.
        • et al.
        Association between hospital volume, processes of care, and outcomes in patients admitted with heart failure: insights from Get With The Guidelines—Heart Failure.
        Circulation. 2018; 137: 1661-1670
        • Alabousi M.
        • Abdullah P.
        • Alter D.A.
        • et al.
        Cardiovascular risk factor management performance in Canada and the United States: a systematic review.
        Can J Cardiol. 2017; 33: 393-404
        • Tu J.V.
        • Chu A.
        • Maclagan L.
        • et al.
        Regional variations in ambulatory care and incidence of cardiovascular events.
        CMAJ. 2017; 189: e494-e501
        • Cheung A.
        • Stukel T.A.
        • Alter D.A.
        • et al.
        Primary care physician volume and quality of diabetes care: a population-based cohort study.
        Ann Intern Med. 2017; 166: 240-247
        • Dahrouge S.
        • Hogg W.
        • Younger J.
        • et al.
        Primary care physician panel size and quality of care: a population-based study in Ontario, Canada.
        Ann Fam Med. 2016; 14: 26-33
        • Doherty P.
        • Harrison A.S.
        • Knapton M.
        • Dale V.
        Observational study of the relationship between volume and outcomes using data from the National Audit of Cardiac Rehabilitation.
        Open Heart. 2015; 2e000304
        • Fleming L.M.
        • Jones P.
        • Chan P.S.
        • et al.
        Relationship of provider and practice volume to performance measure adherence for coronary artery disease, heart failure, and atrial fibrillation: results from the National Cardiovascular Data Registry.
        Circ Cardiovasc Qual Outcomes. 2016; 9: 48-54
        • Bhatia R.S.
        • Bouck Z.
        • Ivers N.M.
        • et al.
        Electrocardiograms in low-risk patients undergoing an annual health examination.
        JAMA Intern Med. 2017; 177: 1326-1333
        • National Cholesterol Education Program (NCEP)
        Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Third report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) final report.
        Circulation. 2002; 106: 3143-3421
        • McPherson R.
        • Frohlich J.
        • Fodor G.
        • Genest J.
        • Canadian Cardiovascular Society
        Canadian Cardiovascular Society position statement—recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease.
        Can J Cardiol. 2006; 22: 913-927
        • Genest J.
        • McPherson R.
        • Frohlich J.
        • et al.
        2009 Canadian Cardiovascular Society/Canadian guidelines for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease in the adult—2009 recommendations.
        Can J Cardiol. 2009; 25: 567-579
        • Anderson T.J.
        • Grégoire J.
        • Hegele R.A.
        • et al.
        2012 update of the Canadian Cardiovascular Society guidelines for the diagnosis and treatment of dyslipidemia for the prevention of cardiovascular disease in the adult.
        Can J Cardiol. 2013; 29: 151-167
        • Anderson T.J.
        • Gregoire J.
        • Pearson G.J.
        • et al.
        2016 Canadian Cardiovascular Society guidelines for the management of dyslipidemia for the prevention of cardiovascular disease in the adult.
        Can J Cardiol. 2016; 32: 1263-1282
        • Pearson G.J.
        • Thanassoulis G.
        • Anderson T.J.
        • et al.
        2021 Canadian Cardiovascular Society guidelines for the management of dyslipidemia for the prevention of cardiovascular disease in adults.
        Can J Cardiol. 2021; 37: 1129-1150
        • Stone N.J.
        • Robinson J.G.
        • Lichtenstein A.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.
        J Am Coll Cardiol. 2014; 63: 2889-2934
        • Grundy S.M.
        • Stone N.J.
        • Bailey A.L.
        • et al.
        2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.
        J Am Coll Cardiol. 2019; 73: e285-e350
        • Tran D.T.
        • Palfrey D.
        • Lo T.K.T.
        • Welsh R.
        Outcome and cost of optimal control of dyslipidemia in adults with high risk for cardiovascular disease.
        Can J Cardiol. 2021; 37: 66-76
        • Tu J.V.
        • Chu A.
        • Donovan L.R.
        • et al.
        The Cardiovascular Health in Ambulatory Care Research Team (CANHEART): using big data to measure and improve cardiovascular health and healthcare services.
        Circ Cardiovasc Qual Outcomes. 2015; 8: 204-212
        • Shah B.R.
        • Chiu M.
        • Amin S.
        • et al.
        Surname lists to identify South Asian and Chinese ethnicity from secondary data in Ontario, Canada: a validation study.
        BMC Med Res Methodol. 2010; 10: 42
        • Schultz S.E.
        • Glazier R.H.
        Identification of physicians providing comprehensive primary care in Ontario: a retrospective analysis using linked administrative data.
        CMAJ Open. 2017; 5: e856-e863
        • Stukel T.A.
        • Glazier R.H.
        • Schultz S.E.
        • et al.
        Multispecialty physician networks in Ontario.
        Open Med. 2013; 7: e40-e55
        • Fernandes K.A.
        • Sutradhar R.
        • Borkhoff C.M.
        • et al.
        Small-area variation in screening for cancer, glucose and cholesterol in Ontario: a cross-sectional study.
        CMAJ Open. 2015; 3: e373-e381
        • Statistics Canada
        Canadian Community Health Survey (CCHS)—2018.
        (Available at:)
        • d’Agostino R.B.
        • Vasan R.S.
        • Pencina M.J.
        • et al.
        General cardiovascular risk profile for use in primary care: the Framingham Heart Study.
        Circulation. 2008; 117: 743-753
        • Tu J.V.
        • Chu A.
        • Rezai M.R.
        • et al.
        The incidence of major cardiovascular events in immigrants to Ontario, Canada: the CANHEART Immigrant Study.
        Circulation. 2015; 132: 1549-1559
        • Panageas K.S.
        • Schrag D.
        • Russell Localio A.
        • Venkatraman E.S.
        • Begg C.B.
        Properties of analysis methods that account for clustering in volume-outcome studies when the primary predictor is cluster size.
        Stat Med. 2007; 26: 2017-2035
        • Sterne J.A.
        • White I.R.
        • Carlin J.B.
        • et al.
        Multiple imputation for missing data in epidemiological and clinical research: potential and pitfalls.
        BMJ. 2009; 338: b2393
        • Austin P.C.
        • Lee D.S.
        • Fine J.P.
        Introduction to the analysis of survival data in the presence of competing risks.
        Circulation. 2016; 133: 601-609
        • Kiran T.
        • Glazier R.H.
        • Campitelli M.A.
        • Calzavara A.
        • Stukel T.A.
        Relation between primary care physician supply and diabetes care and outcomes: a cross-sectional study.
        CMAJ Open. 2016; 4: E80-E87