Martin O'Flaherty

Coronary heart disease trends in England and Wales from 1984 to 2004: concealed levelling of mortality rates among young adults

Background: Trends in cardiovascular risk factors among UK adults present a complex picture. Ominous increases in obesity and diabetes among young adults raise concerns about subsequent coronary heart disease (CHD) mortality rates in this group. Objective: To examine recent trends in age-specific mortality rates from CHD, particularly those among younger adults. Methods and results: Mortality data from 1984 to 2004 were used to calculate age-specific mortality rates for British adults aged 35+ years, and joinpoint regression was used to assess changes in trends. Overall, the age-adjusted mortality rate decreased by 54.7% in men and by 48.3% in women. However, among men aged 35–44 years, CHD mortality rates in 2002 increased for the first time in over two decades. Furthermore, the recent declines in CHD mortality rates seem to be slowing in both men and women aged 45–54. Among older adults, however, mortality rates continued to decrease steadily throughout the period. Conclusions: The flattening mortality rates for CHD among younger adults may represent a sentinel event. Deteriorations in medical management of CHD appear implausible. Thus, unfavourable trends in risk factors for CHD, specifically obesity and diabetes, provide the most likely explanation for the observed trends.

Rapid mortality falls after risk-factor changes in populations.

The recent Lancet Series on chronic diseases and development suggests that prevention policies are eff ective and cost eff ective. However, this eff ectiveness raises another impor tant question: how quickly might benefi ts follow improvements in risk factors in entire populations? Many investigators have assumed that this lag might be of several decades and, indeed, the development of atheroma—the underlying pathological process preceding most coronary and stroke events—normally takes many decades to progress. Thus arterial stiff ening can be shown in children who are obese, and aortic fatty streaks are visible in some teenagers and young adults. Yet most cardiovascular events manifest only after the age of 60 years. Hence, the perception is of a process that builds slowly over decades and that will reverse slowly, if at all. But this perception is wrong. Extensive empirical and trial evidence shows that substantial reductions in mortality can occur within months of decreases in smoking, and within 1–3 years of dietary changes. This reduction applies to both individuals and to entire populations. To take some examples, Helena is an isolated community in Montana, USA, with one hospital. After local smoke-free legislation was introduced in 2002, admissions for acute coronary syndrome decreased by 40% in 6 months. However, the law was then rescinded and coronary admissions returned to past levels, again within 6 months. Similarly, smoke-free legislation in Scotland, UK, in 2006 was followed even more rapidly by a 17% decrease in hospital admissions and, crucially, by a 6% decrease in out-of-hospital cardiac deaths. Equally rapid decreases in mortality have been seen in other populations after smoke-free legislation. *Bruno Moonen, Justin M Cohen Clinton Health Access Initiative, Nairobi , Kenya bmoonen@clintonhealthaccess.org

Contributions of treatment and lifestyle to declining CVD mortality: why have CVD mortality rates declined so much since the 1960s?

Developed countries have enjoyed substantial falls in cardiovascular disease (CVD) mortality. However, low and middle income countries are drowning in a rising tide of CVD and other non-communicable diseases. Current and future trends in CVD mortality will therefore require increasing attention in the 21st century. The success of clinical cardiology in providing evidence-based cost-effective treatments should be celebrated. However, the growing understanding of CVD mortality trends highlights the crucial role of tobacco, diet, alcohol and inactivity as key drivers. Pro-active public health approaches focused on ‘upstream’ population-wide policies are increasingly recognised as being potentially powerful, rapid, equitable and cost-saving. However, the future political challenges could be substantial.

Coronary heart disease mortality among young adults in Scotland in relation to social inequalities: time trend study

Objective To examine recent trends and social inequalities in age specific coronary heart disease mortality. Design Time trend analysis using joinpoint regression. Setting Scotland, 1986-2006. Participants Men and women aged 35 years and over. Main outcome measures Age adjusted and age, sex, and deprivation specific coronary heart disease mortality. Results Persistent sixfold social differentials in coronary heart disease mortality were seen between the most deprived and the most affluent groups aged 35-44 years. These differentials diminished with increasing age but equalised only above 85 years. Between 1986 and 2006, overall, age adjusted coronary heart disease mortality decreased by 61% in men and by 56% in women. Among middle aged and older adults, mortality continued to decrease fairly steadily throughout the period. However, coronary heart disease mortality levelled from 1994 onwards among young men and women aged 35-44 years. Rates in men and women aged 45-54 showed similar flattening from about 2003. Rates in women aged 55-64 may also now be flattening. The flattening of coronary heart disease mortality in younger men and women was confined to the two most deprived fifths. Conclusions Premature death from coronary heart disease remains a major contributor to social inequalities. Furthermore, the flattening of the decline in mortality for coronary heart disease among younger adults may represent an early warning sign. The observed trends were confined to the most deprived groups. Marked deterioration in medical management of coronary heart disease seems implausible. Unfavourable trends in the major risk factors for coronary heart disease (smoking and poor diet) thus provide the most likely explanation for these inequalities.

Patterns of coronary heart disease mortality over the 20th century in England and Wales: Possible plateaus in the rate of decline

BackgroundCoronary heart disease (CHD) rates in England and Wales between 1950 and 2005 were high and reasonably steady until the mid 1970s, when they began to fall. Recent work suggests that the rate of change in some groups has begun to decrease and may be starting to plateau or even reverse.MethodsData for all deaths between 1931 and 2005 in England and Wales were grouped by year, sex, age at death and contemporaneous ICD code for CHD as cause of death. CHD mortality rates by calendar year and birth cohort were produced for both sexes and rates of change were examined.ResultsThe pattern of increased burden of CHD mortality within older age groups has only recently emerged in men, whereas it has been established in women for far longer. CHD mortality rates among younger people showed little variation by birth cohort. For younger women (49 and under), the rate of change in CHD mortality has reversed in the last 20 years, indicating a future plateau and possible reversal of previous improvement in CHD mortality rates. Among younger men the rate of change in CHD mortality has been consistent for the past 15 years indicating that rates in this group have continued to fall steadily.ConclusionAlthough CHD mortality rates continue to drop in older age groups the actual burden of coronary heart disease is increasing due to the ageing of the population. The rate of improvement in CHD mortality appears to be beginning to decline and may even be reversing among younger women.

Estimating the cardiovascular mortality burden attributable to the European Common Agricultural Policy on dietary saturated fats

OBJECTIVE To estimate the burden of cardiovascular disease within 15 European Union countries (before the 2004 enlargement) as a result of excess dietary saturated fats attributable to the Common Agricultural Policy (CAP). METHODS A spreadsheet model was developed to synthesize data on population, diet, cholesterol levels and mortality rates. A conservative estimate of a reduction in saturated fat consumption of just 2.2 g was chosen, representing 1% of daily energy intake. The fall in serum cholesterol concentration was then calculated, assuming that this 1% reduction in saturated fat consumption was replaced with 0.5% monounsaturated and 0.5% polyunsaturated fats. The resulting reduction in cardiovascular and stroke deaths was then estimated, and a sensitivity analysis conducted. FINDINGS Reducing saturated fat consumption by 1% and increasing monounsaturated and polyunsaturated fat by 0.5% each would lower blood cholesterol levels by approximately 0.06 mmol/l, resulting in approximately 9800 fewer coronary heart disease deaths and 3000 fewer stroke deaths each year. CONCLUSION The cardiovascular disease burden attributable to CAP appears substantial. Furthermore, these calculations were conservative estimates, and the true mortality burden may be higher. The analysis contributes to the current wider debate concerning the relationship between CAP, health and chronic disease across Europe, together with recent international developments and commitments to reduce chronic diseases. The reported mortality estimates should be considered in relation to the current CAP and any future reforms.

Persistent socioeconomic inequalities in cardiovascular risk factors in England over 1994-2008: A time-trend analysis of repeated cross-sectional data

BackgroundOur aims were to determine the pace of change in cardiovascular risk factors by age, gender and socioeconomic groups from 1994 to 2008, and quantify the magnitude, direction and change in absolute and relative inequalities.MethodsTime trend analysis was used to measure change in absolute and relative inequalities in risk factors by gender and age (16-54, ≥ 55 years), using repeated cross-sectional data from the Health Survey for England 1994-2008. Seven risk factors were examined: smoking, obesity, diabetes, high blood pressure, raised cholesterol, consumption of five or more daily portions of fruit and vegetables, and physical activity. Socioeconomic group was measured using the Index of Multiple Deprivation 2007.ResultsBetween 1994 and 2008, the prevalence of smoking, high blood pressure and raised cholesterol decreased in most deprivation quintiles. However, obesity and diabetes increased. Increasing absolute inequalities were found in obesity in older men and women (p = 0.044 and p = 0.027 respectively), diabetes in young men and older women (p = 0.036 and p = 0.019 respectively), and physical activity in older women (p = 0.025). Relative inequality increased in high blood pressure in young women (p = 0.005). The prevalence of raised cholesterol showed widening absolute and relative inverse gradients from 1998 onwards in older men (p = 0.004 and p ≤ 0.001 respectively) and women (p ≤ 0.001 and p ≤ 0.001).ConclusionsFavourable trends in smoking, blood pressure and cholesterol are consistent with falling coronary heart disease death rates. However, adverse trends in obesity and diabetes are likely to counteract some of these gains. Furthermore, little progress over the last 15 years has been made towards reducing inequalities. Implementation of known effective population based approaches in combination with interventions targeted at individuals/subgroups with poorer cardiovascular risk profiles are therefore recommended to reduce social inequalities.

Analysing the large decline in coronary heart disease mortality in the Icelandic population aged 25-74 between the years 1981 and 2006.

Background Coronary heart disease (CHD) mortality rates have been decreasing in Iceland since the 1980s. We examined how much of the decrease between 1981 and 2006 could be attributed to medical and surgical treatments and how much to changes in cardiovascular risk factors. Methodology The previously validated IMPACT CHD mortality model was applied to the Icelandic population. The data sources were official statistics, national quality registers, published trials and meta-analyses, clinical audits and a series of national population surveys. Principal Findings Between 1981 and 2006, CHD mortality rates in Iceland decreased by 80% in men and women aged 25 to 74 years, which resulted in 295 fewer deaths in 2006 than if the 1981 rates had persisted. Incidence of myocardial infarction (MI) decreased by 66% and resulted in some 500 fewer incident MI cases per year, which is a major determinant of possible deaths from MI. Based on the IMPACT model approximately 73% (lower and upper bound estimates: 54%–93%) of the mortality decrease was attributable to risk factor reductions: cholesterol 32%; smoking 22%; systolic blood pressure 22%, and physical inactivity 5% with adverse trends for diabetes (−5%), and obesity (−4%). Approximately 25% (lower and upper bound estimates: 8%–40%) of the mortality decrease was attributable to treatments in individuals: secondary prevention 8%; heart failure treatments 6%; acute coronary syndrome treatments 5%; revascularisation 3%; hypertension treatments 2%, and statins 0.5%. Conclusions Almost three quarters of the large CHD mortality decrease in Iceland between 1981 and 2006 was attributable to reductions in major cardiovascular risk factors in the population. These findings emphasize the value of a comprehensive prevention strategy that promotes tobacco control and a healthier diet to reduce incidence of MI and highlights the potential importance of effective, evidence based medical treatments.

Coronary heart disease mortality trends in the Netherlands 1972–2007

Background Coronary heart disease (CHD) mortality has steadily declined since the early 1970s in the Netherlands. However, in some Western countries the rate of decline in younger groups may be starting to plateau or even rise. Objective To examine trends in age-specific CHD mortality rates among Dutch adults from 1972 to 2007, with a particular focus on recent trends for the younger age groups Methods Data for all CHD deaths (1972–2007) in the Netherlands were grouped by year, sex, age. A joinpoint regression was fitted to each age-sex-group to detect points in time at which significant changes in the trends occur. For every time period, the linear slope of the trend, p value, observed number of deaths, CHD mortality rates and change in the CHD mortality rate were calculated. Results Between 1972 and 2007, the age-adjusted CHD mortality rates decreased overall by 76% in both men and women. In men (35–54 years), the change in CHD mortality rate in the period 1980–1993 was −0.53 but attenuated in period 1993–1999: −0.16. In women (35–54 years) the decline likewise attenuated to −0.44 in period 1979–1989: and −0.05 in period 1989–2000. After 1999–2000, CHD mortality rate further declined in both men (period 1999–2007: −0.46) and women (period 2000–2007: −0.38). Conclusions Evidence from several Western countries suggests that among young adults (<55 years), CHD mortality rates are levelling out. In this study, similar attenuation of the decline in CHD mortality among young adults in the Netherlands has been observed. Furthermore, this is the first study to observe a subsequent increase in the pace of decline after a period of flattening. In order to better explain these encouraging changes in CHD mortality rates, a detailed analysis of recent changes in cardiovascular risk factors and treatments is now urgently required.

Potential cardiovascular mortality reductions with stricter food policies in the United Kingdom of Great Britain and Northern Ireland

OBJECTIVE To estimate how much more cardiovascular disease (CVD) mortality could be reduced in the United Kingdom through more progressive nutritional targets. METHODS Potential reductions in CVD mortality in the United Kingdom between 2006 (baseline) and 2015 were estimated by synthesizing data on population, diet and mortality among adults aged 25 to 84 years. The effect of specific dietary changes on CVD mortality was obtained from recent meta-analyses. The potential reduction in CVD deaths was then estimated for two dietary policy scenarios: (i) modest improvements (simply assuming recent trends will continue until 2015) and (ii) more substantial but feasible reductions (already seen in several countries) in saturated fats, industrial trans fats and salt consumption, plus increased fruit and vegetable intake. A probabilistic sensitivity analysis was conducted. Results were stratified by age and sex. FINDINGS The first scenario would result in approximately 12 500 fewer CVD deaths per year (range: 5500-30 300). Approximately 4800 fewer deaths from coronary heart disease and 1800 fewer deaths from stroke would occur among men, and 3500 and 2400 fewer, respectively, would occur among women. More substantial dietary improvements (no industrial trans fats, reduction in saturated fats and salt and substantial increases in fruit and vegetable intake) could result in approximately 30 000 fewer (range: 13 300-74 900) CVD deaths. CONCLUSION Excess dietary trans fats, saturated fats and salt, along with insufficient fruits and vegetables, generate a substantial burden of CVD in the United Kingdom. Further improvements resembling those attained by other countries are achievable through stricter dietary policies.