The contribution of primary prevention medication and dietary change in coronary mortality reduction in England between 2000 and 2007: a modelling study

Abstract

Objective: To analyse the falls in coronary heart disease (CHD) mortality in England between 2000 and 2007 and quantify the relative contributions from preventive medications and population-wide changes in blood pressure (BP) and cholesterol levels, particularly by exploring socioeconomic inequalities. Design: A modelling study. Setting: Sources of data included controlled trials and meta-analyses, national surveys and official statistics. Participants: English population aged 25+ in 2000–2007. Main outcome measures: Number of deaths prevented or postponed (DPPs) in 2007 by socioeconomic status. We used the IMPACT SEC model which applies the relative risk reduction quantified in previous randomised controlled trials and meta-analyses to partition the mortality reduction among specific treatments and risk factor changes. Results: Between 2000 and 2007, approximately 20 400 DPPs were attributable to reductions in BP and cholesterol in the English population. The substantial decline in BP was responsible for approximately 13 000 DPPs. Approximately 1800 DPPs came from medications and some 11 200 DPPs from population-wide changes. Reduction in population BP prevented almost twofold more deaths in the most deprived quintile compared with the most affluent. Reduction in cholesterol resulted in approximately 7400 DPPs; approximately 5300 DPPs were attributable to statin use and approximately 2100 DPPs to population-wide changes. Statins prevented almost 50% more deaths in the most affluent quintile compared with the most deprived. Conversely, population-wide changes in cholesterol prevented threefold more deaths in the most deprived quintile compared with the most affluent. Conclusions: Population-wide secular changes in systolic blood pressure (SBP) and cholesterol levels helped to substantially reduce CHD mortality and the associated socioeconomic disparities. Mortality reductions were, in absolute terms, greatest in the most deprived quintiles, mainly reflecting their bigger initial burden of disease. Statins for high-risk individuals also made an important contribution but maintained socioeconomic inequalities. Our results strengthen the case for greater emphasis on preventive approaches, particularly population-based policies to reduce SBP and cholesterol.