Explaining trends in coronary heart disease in the Netherlands Carla Koopman Explaining trends in coronary heart disease in the Netherlands PhD thesis, Utrecht University, the Netherlands ISBN: 978-90-393-6295-2 Author: Carla Koopman Cover design: Lisette Tegelberg, lizzilcreative.nl Lay-out: Carla Koopman Printed by: CPI Koninklijke Wöhrmann, Zutphen Explaining trends in coronary heart disease in the Netherlands Het verklaren van trends in coronaire hartziekten in Nederland (met een samenvatting in het Nederlands) Proefschrift ter verkrijging van de graad van doctor aan de Universiteit Utrecht op gezag van de rector magnificus, prof. dr. G.J. van der Zwaan, ingevolge het besluit van het college door promoties in het openbaar te verdedigen op donderdag 2 april 2015 des middags te 2.30 uur door Carla Koopman geboren op 2 april 1985 te Pijnacker Promotoren: Prof. dr. M.L. Bots Prof. dr. S. Capewell Copromotoren: Dr. I. Vaartjes Dr. ir. I. van Dis The research described in this thesis was supported by a grant of the Dutch Heart Foundation (2008T111). Financial support by the Dutch Heart Foundation for the publication of this thesis is gratefully acknowledged. TABLE OF CONTENTS TABLE OF CONTENTS Chapter 1. General introduction 9 9 Chapter 2. Trends in incidence, case-fatality and hospitalization rates 2.1 Trends and inequalities in incidence and outcome of acute 1717 myocardial infarction (Int J Cardiol 2013) 2.2 Shifts in the age distribution and from acute to chronic 3737 coronary heart disease hospitalizations (Eur J Prev Cardiol 2014) Chapter 3. Explanation of trends: the role of socioeconomic status 3.1 Socioeconomic inequalities in acute myocardial infarction 53 53 incidence (BMC Public Health 2012) 3.2 Socioeconomic inequalities in short-term mortality after 75 75 acute myocardial infarction (Eur J Epidemiol 2012) Chapter 4. Explanation of trends: the role of risk factors 93 93 Trends in risk factors for coronary heart disease (submitted) Chapter 5. Explanation of trends: the role of medication 109109 Trends in cardiovascular drug use for primary prevention, secondary prevention and acute phase treatment of coronary heart disease (Eur Heart J 2013) Chapter 6. Explanation of trends: the IMPACTSEC model 131355 Explaining the decline in coronary heart disease mortality in the Netherlands (submitted) Chapter 7. General discussion 193193 Chapter 8. Summary 21321 1 Nederlandse samenvatting 215 Dankwoord 22322 1 Curriculum Vitae 22922 7 List of publications 2312 29 CHAPTER 1 GENERAL INTRODUCTION Chapter 1 BACKGROUND Last decade an accelerated decline in mortality rate accompanied by a dramatic increase in life expectancy was observed in the Netherlands. Two-thirds of the increase in life expectancy at birth since 2002 were due to declines in mortality among those aged 65 and over.1 The increase in life expectancy has been largely attributed to the decline in coronary heart disease (CHD) mortality rates. These fell with 48% between 1997 and 2007 (Figure 1). This meant that 11,200 fewer CHD deaths occurred in 2007 than would have been expected for the Dutch population if 1997 mortality rates had persisted. Lower mortality rates may result from lower incidence rates and/or lower case-fatality rates. Important drivers of changes in incidence and case fatality are changes in risk factors, changes in treatment during the acute phase of the disease and changes in secondary prevention therapy. 450 400 350 300 250 200 150 100 standardized CHD mortality rateper 100.000 - 50 Men Women Age 1997 2007 0 1974 1972 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 1970 Year Figure 1 Age-standardized coronary heart disease (CHD) mortality rate in the Netherlands between 1970 and 2012. Mortality rates were standardized to the age distribution of the Dutch population in 2012. Data source: Dutch Heart Foundation. Studying time trends in CHD incidence, case-fatality and mortality rates is important. The resulting information is highly suggestive as to what might be expected in the future. In addition, they are an effective approach to evaluate previous health policies. Trends in incidence or mortality of disease are not fixed across a population. Generally trends tend to differ across age and sex groups. Many previous studies have only presented time trends in CHD incidence or mortality rates as age- 10 General introduction standardized rates by period.2-5 Age standardization is relevant for comparison between calendar years within studies, or for comparison across studies, but with standardization information is also lost. For example, falls in AMI incidence have 1 been reported to be greater in men than women.4,6,7 Furthermore, in young adults flattening of the CHD decline and even increases in AMI incidence have been observed.8,9 It is therefore relevant to study the dynamics of national trends. Capewell and colleagues developed and refined a model, the IMPACT model, to explore declines in CHD mortality in a variety of populations, and comprehensively assess the potential contribution of medical treatments and risk factor changes to the decline. The model was validated against the actual mortality falls observed in the UK, Scotland, Ireland, Finland, Sweden, Spain, Portugal, Czech Republic, Poland, Ontario, USA, New Zealand, Turkey, Syria, China and other countries.10-23 Results from these models indicated that changes in risk factors explained 50-75% of the CHD mortality decline and changes in treatment uptakes 25-50%. In this thesis we will present these data for the Netherlands. Very limited and fragmented information was available on time trends in risk factors and on cardiovascular drug uptakes that could explain the large decline in CHD mortality between 1997 and 2007. Also, trends tend to differ by socioeconomic status being more favourable for the most affluent group. As a consequence, the IMPACT CHD model recently addressed policy questions taking socioeconomic circumstances (SEC) into account.10,24 These analyses showed that in the UK and Scotland indeed CHD mortality trends were more favourable for the most affluent and therefore the gap between the highest and lowest socioeconomic groups is actually widening.10,24 Socioeconomic inequalities also exist in the Netherlands. The healthy life expectancy without physical limitations is 14 years lower for men with low education compared to men with a high education; for women the difference is even 15 years.25 Although socioeconomic inequalities in CHD have been studied for several countries, information for the Netherlands is limited. Objectives of this thesis The first objective of this thesis was to explain the decline in CHD mortality in the Netherlands between 1997 and 2007 by applying the IMPACT model to Dutch data. The second objective was to provide detailed information (by age, sex and socioeconomic circumstances) on time trends in CHD mortality, incidence, short- term case-fatality rates, risk factors, drug treatments and uptake of other cardiovascular medical treatments. 11 Chapter 1 Outline In chapter 2.1, we studied time trends in acute myocardial infarction (AMI) incidence, including out-of-hospital mortality and hospitalized case-fatality rates. In addition, we compared AMI trends by age, sex and socioeconomic circumstances. In chapter 2.2, we investigated whether the large declines in AMI rates between 1998 and 2007 also applied to other types of CHD (unstable angina and chronic CHD). We observed shifts in the age distribution and from acute to chronic CHD hospitalizations. In chapter 3 we focussed specifically on the role of socioeconomic circumstances. In chapter 3.1, we compared the magnitude of socioeconomic inequalities in the incidence of AMI by age and sex. In chapter 3.2, we investigated socioeconomic inequalities in short-term case-fatality rates of AMI by age and sex. In chapter 4, we described age-sex-specific time trends in risk factors for CHD between 1988-2010. In chapter 5, we studied time trends in cardiovascular drug use for prevention and treatment of CHD between 1998-2010. We described age-sex-specific cardiovascular drug use for primary prevention, secondary prevention and acute phase treatment of CHD. In chapter 6, we used Dutch data to explain the decline in CHD mortality between 1997 and 2007 by age, sex and socioeconomic group by applying the IMPACTSEC model. In chapter 7, the general discussion, we compared our IMPACT results with previous IMPACT models applied in other countries and implications and recommendations for future research and clinical management are considered. Finally, a summary of the main results presented in this thesis is given in chapter 8. REFERENCES 1. Mackenbach JP, Slobbe L, Looman CW, van der HA, Polder J, Garssen J. Sharp upturn of life expectancy in the Netherlands: effect of more health care for the elderly? Eur J Epidemiol 2011;26:903-14. 2. Chimonas T, Fanouraki I, Liberopoulos EN, Chimonas E, Elisaf M. Diverging trends in cardiovascular morbidity and mortality in a low risk population. Eur J Epidemiol 2009;24: 415-23. 3. de Henauw S., de Bacquer D., de Smet P., Kornitzer M, de Backer G. Trends in coronary heart disease in two Belgian areas: results from the MONICA Ghent-Charleroi Study. J Epidemiol Community Health 1999;53:89-98. 4. Yang D, Dzayee DA, Beiki O, de FU, Alfredsson L, Moradi T. Incidence and case fatality after day 28 of first time myocardial infarction in Sweden 1987-2008. Eur J Prev Cardiol 2011 Nov 7. 5. Yeh RW, Sidney S, Chandra M, Sorel M, Selby JV, Go AS. Population trends in the incidence and outcomes of acute myocardial infarction. N Engl J Med 2010 10;362:2155-65. 12 General introduction 6. Lehto HR, Lehto S, Havulinna AS, Ketonen M, Lehtonen A, Kesaniemi YA, et al. Are coronary event rates declining slower in women than in men - evidence from two population-based myocardial infarction registers in Finland? BMC Cardiovasc Disord 2007;7:35.