Heart disease is placing an increasing burden on black Africans, say researchers, who call for more awareness and better screening to identify patients at risk.
Although well documented in developed countries, few data exist on heart disease in low- and middle-income countries, where malnutrition, bacterial infection and poor medical resources can amplify the risk.
Researchers from the Soweto Cardiovascular Research Unit at the Chris Hani Baragwanath Hospital in Johannesburg looked at heart disease in Soweto, which has the largest urban concentration of black Africans in South Africa.
The study, published in The Lancet this month (15 March), examined 4,162 patients with heart disease during 2006.
The team found that heart disease in Soweto is associated with infectious disease — common in African populations — but with an increasing link to non-communicable diseases, such as obesity, usually associated with high-income countries.
"This study is indicative of urban communities across Africa," says Kemilembe Tibazarwa, one of the authors of the paper."
Heart failure was most common among black Africans. Fifty-six per cent of patients had hypertension and 44 per cent of those were classified as obese. Two-thirds of patients were found to be vulnerable to several risk factors at once.
Most would have benefited from earlier diagnosis, say the researchers.
"Heart failure arises from heart defects," says Lucas Ntyintyane, another of the authors. For cardiac damage attributable to bacterial infection, "patients moved straight from the infected to the chronic stage, simply because the infectious stage was not treated."
The authors write that screening programmes for schoolchildren, as well as portable, cost-effective technologies for screening in low-income settings, could help pick up early signs of heart disease.
Better community awareness of the signs and symptoms of heart disease would also encourage people at risk to seek treatment earlier.
An accompanying article in The Lancet says that lifestyle changes also contribute. Africans moving from rural to urban areas may switch from outdoor work to being deskbound, and from fresh food to a processed diet containing more salt — increasing the risk of hypertension.
Ntyintyane hopes that the study will help raise awareness of cardiovascular disease in Africa. "Now we know heart disease in Africans is not a myth, we can begin educating people on lifestyle and heart disease.″"
The Lancet 371, 915 (2008)