Cardiovascular Journal of Africa: Vol 33 No 4 (JULY/AUGUST 2022)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 4, July/August 2022 AFRICA 167 Editorial A report card for healthy aging in South Africa Dirk J Blom DOI: 10.5830/CVJA-2022-047 Increasing urbanisation and the changes in lifestyle and diet that accompany the transition from a rural, agrarian lifestyle to urban living, with its ready availability of high-energy-density processed foods and low requirements for physical activity is associated with increasing rates of non-communicable diseases (NCD).1 Changes in lifestyle and diet resulting from urbanisation are followed by the appearance of physiological risk factors such as overweight and obesity, hypertension, diabetes and dyslipidaemia. These risk factors are mostly asymptomatic, but given sufficiently long exposure, clinically overt disease ensues in many individuals. The increasing rates of atherosclerotic cardiovascular disease in South Africans illustrate this trajectory well. Atherosclerosis is a complex, multifactorial disorder but simplistically can be conceptualised as accumulation of atherogenic lipoproteins [represented mainly by low-density lipoprotein cholesterol (LDLC)] in the vascular wall. This accumulation can be quantified by a cholesterol-year score.2 Once the cholesterol-year score reaches a critical threshold, clinical complications, such as myocardial infarction or stroke, may occur. The threshold for disease is lowered by factors that negatively affect the endothelium and increase inflammation, such as smoking, hypertension, lack of exercise and diabetes. As diets change, the concentrations of LDL-C and other atherogenic lipoproteins, such as remnants, increase the rate of cholesterol accumulation. Simultaneously, the threshold at which disease can become clinically manifest is lowered by the factors outlined above. A long asymptomatic period is followed by the often sudden appearance of a major adverse cardiovascular event. This phenomenon is dramatically illustrated by changes in admission diagnoses at Baragwanath Hospital in Soweto. Whereas acute myocardial infarction was seldom seen in the 1970s, the hospital now has a busy coronary care unit, admitting patients with myocardial infarctions every day.3 The demographic transition, with increasing numbers of older individuals, is another important driver of the increase in NCDs, as a greater proportion of the population lives long enough for these disorders to manifest themselves.4 Although metabolic and vascular abnormalities can often be detected early in infancy or in childhood, for example, fatty streaks are found in the arteries of many children, clinically overt disease often occurs only in middle age or later.5 Ideally, one would therefore design population interventions that target lifestyle and dietary factors very early, preventing the development of physiological risk factors and preventing the next generation from ‘paying for the sins of their forefathers’ through epigenetic programming.6 Middle-aged and older adults are however at greatest absolute risk of dying or becoming disabled within the foreseeable future. Because national surveys have shown that middle-aged adults (45–65 years) are at highest risk for many of the NCD risk factors and middle-aged adults are mostly economically active and often support large extended families, Professor Lisa Mickelsfield and colleagues from the SAMRC/Wits Developmental Pathways for Health Research Unit at the University of the Witwatersrand focused their attention on this age group in this first South African report card on healthy aging (page 200)7. In this extensive systematic review of the literature, the authors assign scores for the adequacy of prevalence data and assess whether national policies exist, and are implemented, for a variety of lifestyle and physiological risk factors. The lifestyle risk factors considered are unhealthy diets, physical inactivity, harmful use of alcohol and tobacco use. The physiological risk factors considered are overweight and obesity, hypertension, dyslipidaemia and poor glucose control. This is an important and arduous task. If we do not know the magnitude of a problem and whether it affects certain groups preferentially, divided for instance by gender, geography or race more than others, then it is very hard to design and target interventions correctly. Similarly, a good understanding of current policies and their implementation (or lack of) is required when considering new strategies to deal with NCD risk factors. So how does South Africa score on the report card for prevalence data? Not unexpectedly, our performance is patchy, with significant room for improvement in many areas. For most of the lifestyle and physiological risk factors, there are shards of information. In some areas these shards can be put together to form a coherent mosaic that probably does accurately reflect the current situation in South Africa. In other areas, the available information remains fragmentary, and much is left to the imagination when trying to get a complete picture. Because the information often comes from multiple studies, there are at times significant differences in methodology, for example, in how dietary information was collected and analysed, and to stay with the metaphor, we are therefore often trying to assemble a mosaic using both glass and stone shards. The areas for which we have data graded as A (published national and regional prevalence data available for the 45–65year age group) are alcohol consumption, obesity, diabetes and hypertension. This is perhaps not surprising, given the major societal impact of these disorders. The reported rates of hazardous alcohol consumption do vary between regions and studies, but a consistent pattern is that hazardous drinking is much more Division of Lipidology, Department of Medicine and Cape Heart Institute, University of Cape Town, South Africa Dirk J Blom, MD, dirk.blom@uct.ac.za

RkJQdWJsaXNoZXIy NDIzNzc=