Most Socioeconomic Differences In Coronary Heart Disease Mortality Could Be Eliminated With Best-Practice Interventions

Heart disease is a major source of mortality and morbidity in many populations, but heart disease has been noted to have different magnitudes of effect on different types of populations. Presently, some of the inteventions used against it can be classified into the best-practice interventions, and involve the reduction of systolic blood pressure by 10mmHg, the reduction of total blood cholesterol by 2 mmol/L, reduction of blood glucose by 1mmol/L in non-diabetics, halving the presence of non-insulin dependent diabetes, and completely stopping smoking. In contrast, primordial prevention is the theoretical effect on a population that has never been exposed to modern life, as reflected by populations that do not have sedentary life-styles, consume low-fat diets, have minimal salt intake, and are unexposed to other major heart disease risk factors.

Professor Mika Kivimäki, University College London, UK, and colleagues examined 17,186 male civil servants between the ages of 40 and 69 years between 1967 and 1970 in the UK, as examined in the Whitehall study. For each man, socioeconomic position was determined by employment grade. The authors compared men of higher with those of lower socioeconomic position, to the best practice interventions, and primordial prevention.

In analyzing the data, they authors found that the 15-year absolute risk of death due to coronary heart disease, beginning at 55 years, was 11 deaths per 100 men in the low-grade employment group and 7.5 per 100 men in the high grade group. In theoretical application of population-wide best-practice interventions, the coronary heart disease mortality would have been reduced by 57%, while the mortality difference between the groups would be reduced by 69%. These values would be even greater in using primordial prevention, as evidenced in 73% and 86% reductions respectively.

In conclusion, the authors note the potential benefit that could be obstained from the implementation of the current best-practice interventions. “Our results suggest that current best-practice interventions to reduce classic coronary risk factors, if successfully implemented in both high and low socioeconomic groups, could eliminate most of the socioeconomic differences in coronary heart disease mortality. Modest further benefits would result if the classic coronary risk factors could be reduced to primordial levels for the whole population.”

Dr Martin Tobias, Ministry of Health, Wellington, New Zealand and Professor Anthony Rodgers, University of Auckland, New Zealand, contributed an accompanying comment in which they criticise the ease with which the recommendation was made: “Kivimäki and colleagues’ key message may seem simple, but simple does not mean easy. There are enormous challenges to be overcome to deliver best-practice intervention to disadvantaged groups, who are often beset with competing priorities, resource constraints, and comorbidities. Yet Kivimäki clearly shows that, if we are serious about eliminating social inequalities in cardiovascular health, we need to concentrate our efforts on the established risk factors and focus on absolute reduction in absolute risk.”