Preventing smoking, lowering cholesterol, controlling blood pressure and curing hepatitis C would greatly reduce the burden of heart attacks, non-AIDS cancers and end-stage liver disease and kidney disease in people living with HIV, according to an analysis of a large North American cohort, published in the journal The Lancet HIV.
The study found that eliminating the traditional risk factors for these conditions would have a far greater impact than optimal HIV treatment on the incidence of the conditions, emphasising the importance of screening and management of these conditions in the lifelong care of people living with HIV.
As antiretroviral therapy has prolonged the lives of people with HIV and greatly reduced the number of deaths from AIDS-defining illnesses, non-AIDS conditions such as cardiovascular disease, end-stage liver disease and cancers have become the most important causes of death in people living with HIV in higher-income countries.
Although HIV is known to increase the risk of cardiovascular disease and some cancers, the relative contributions of HIV-associated risk factors and other risk factors to the development of these conditions in people living with HIV has been unclear. As a consequence, screening for risk factors, and interventions to reduce risk factors for these conditions, have not always been prioritised.
NA-ACCORD brings together clinical cohorts of people living with HIV at more than 200 sites in North America. Together, these cohorts have followed over 180,000 patients who have attended a clinic at least twice.
This analysis of cohort participants looked at people in care, with at least two clinic visits, between January 2000 and December 2014. All cases of heart attack, non-AIDS defining cancer, end-stage liver disease and end-stage kidney disease that occurred after the beginning of follow-up were evaluated for HIV- and non-HIV-related risk factors and compared with cohort participants in the same period who did not have a diagnosis of the condition.
The HIV-related risk factors evaluated were low CD4 count, detectable viral load, AIDS diagnosis and antiretroviral regimen history.
The non-HIV risk factors evaluated were smoking, elevated total cholesterol, hypertension, diabetes, stage 4 chronic kidney disease, statin prescription and hepatitis B or C infection. Age, sex, race and HIV transmission risk category were also considered.
Dr Keri Althoff of Johns Hopkins University calculated the population-attributable fraction, or the proportion of cases that would be avoided in the population if the causal risk factor was removed. This measure captures the impact of risk factors that may have a small individual effect but are widespread in the population, as well as risk factors that have a much greater effect but are less prevalent. It allows epidemiologists to judge which interventions that change risk factors are likely to have the biggest population-level impact.