Cardiovascular risk and events in 17 low-,middle-, and high-income countries

ABSTRACT

BACKGROUNDMore than 80% of deaths from cardiovascular disease are estimated to occur inlow-income and middle-income countries, but the reasons are unknown.METHODSWe enrolled 156,424 persons from 628 urban and rural communities in 17 countries(3 high-income, 10 middle-income, and 4 low-income countries) and assessedtheir cardiovascular risk using the INTERHEART Risk Score, a validated score forquantifying risk-factor burden without the use of laboratory testing (with higherscores indicating greater risk-factor burden). Participants were followed for incidentcardiovascular disease and death for a mean of 4.1 years.RESULTSThe mean INTERHEART Risk Score was highest in high-income countries, intermediatein middle-income countries, and lowest in low-income countries (P<0.001).However, the rates of major cardiovascular events (death from cardiovascularcauses, myocardial infarction, stroke, or heart failure) were lower in high-incomecountries than in middle- and low-income countries (3.99 events per 1000 personyearsvs. 5.38 and 6.43 events per 1000 person-years, respectively; P<0.001). Casefatality rates were also lowest in high-income countries (6.5%, 15.9%, and 17.3%in high-, middle-, and low-income countries, respectively; P = 0.01). Urban communitieshad a higher risk-factor burden than rural communities but lower ratesof cardiovascular events (4.83 vs. 6.25 events per 1000 person-years, P<0.001) andcase fatality rates (13.52% vs. 17.25%, P<0.001). The use of preventive medicationsand revascularization procedures was significantly more common in high-incomecountries than in middle- or low-income countries (P<0.001).CONCLUSIONSAlthough the risk-factor burden was lowest in low-income countries, the rates ofmajor cardiovascular disease and death were substantially higher in low-incomecountries than in high-income countries. The high burden of risk factors in highincome...