Ageing population of people living with HIV in sub-Saharan Africa associated with cardiovascular risk factors

An ageing population of people living with HIV on antiretroviral therapy in countries in sub-Saharan Africa is associated with a significant increase in the prevalence of diabetes and obesity, according to an analysis of 44 countries with data from 2000 to 2016, published in the Journal of the International AIDS Society.

Rates of cardiovascular risk factors and of deaths caused by non-communicable diseases (NCDs) are expected to rise faster over the next decade in sub-Saharan Africa than in any other region. Countries with a larger ageing HIV‐positive population are likely to have an increased prevalence of age‐related NCDs, contributing to NCDs becoming the leading cause of deaths in the region by 2030.

There are three pathways by which an ageing population of people with HIV receiving antiretroviral therapy (ART) increases the prevalence of NCDs:

  • HIV can increase the risk of developing NCDs.
  • Some of the antiretroviral drugs (especially the older ART agents that are often used in Africa) are thought to have side-effects that increase cardiovascular risk factors and co-morbid disease.
  • The increased life expectancy due to ART means that people with HIV are at increased risk of developing age-related NCDs.

Glossary

diabetes

A group of diseases characterized by high levels of blood sugar (glucose). Type 1 diabetes occurs when the body fails to produce insulin, which is a hormone that regulates blood sugar. Type 2 diabetes occurs when the body either does not produce enough insulin or does not use insulin normally (insulin resistance). Common symptoms of diabetes include frequent urination, unusual thirst and extreme hunger. Some antiretroviral drugs may increase the risk of type 2 diabetes.

cardiovascular

Relating to the heart and blood vessels.

hypertension

Raised blood pressure.

morbidity

Illness.

epidemiology

The study of the causes of a disease, its distribution within a population, and measures for control and prevention. Epidemiology focuses on groups rather than individuals.

Although there is evidence from high‐income countries that HIV and ART may increase the prevalence of NCDs, this cannot easily be extrapolated to sub‐Saharan Africa because HIV in high‐income countries is largely restricted to key populations and not the general population.

This is the first study to conduct a panel analysis with several NCD risk factors as outcomes for nearly all countries in sub‐Saharan Africa, using a long time span. The researchers used country-level data from the NCD Risk Factor Collaboration, which compiles data from population surveys, epidemiological studies and other sources in about 200 countries.

The study examined the effect of HIV prevalence and use of ART in countries on cardiovascular risk factors, including the prevalence of diabetes, mean body mass index, the prevalence of being overweight, obesity and hypertension, and mean systolic blood pressure. Fixed‐effects estimation was used to quantify the effect of HIV and ART on the prevalence of risk factors. The models were adjusted for calendar time, the age structure of the population, income and education.

The prevalence of diabetes among people with HIV was found to be 5.8 percentage points (pp) higher (95% CI: 1.8 pp to 9.8 pp; p < 0.01) compared to those without HIV. People on ART had a 4.6 percentage point higher prevalence of diabetes (95% CI: 2.6 pp to 6.6 pp; p < 0.01).

The prevalence of obesity was increased by 14.7 percentage points (95% CI: 2.5 pp to 26.9 pp; p < 0.05) for people with HIV. Receiving ART was associated with an increased obesity prevalence of 14.0 percentage points (95% CI: 4.8 pp to 23.2 pp; p < 0.01), whereas taking ART had no significant association with the prevalence of being overweight. The population aged 40 to 59 and older than 60 were more likely to be obese by 23.4 percentage points (95% CI 5.6 pp to 41.3 pp) and 54.7 percentage points (95% CI 3.4 pp to 106.1 pp) respectively.

There were no significant associations between the prevalence of hypertension and HIV prevalence or ART use.

The increasing prevalence of these cardiovascular risk factors emphasises the need for comprehensive healthcare programmes that screen and treat both HIV and non‐communicable diseases to decrease the associated morbidity and mortality rates, the authors conclude.