Poor physical growth a common problem among HIV-positive adolescents in low- and middle-income countries

Starting HIV treatment late is a key risk factor

There is a high prevalence of stunted physical growth among HIV-positive adolescents living in low- and middle-income countries, investigators report in the Journal of the International AIDS Society. Approximately 50% had stunted growth at the time antiretroviral therapy (ART) was started. After the age of 12 years, adolescent boys were especially likely to have poorer than expected growth.

“Growth retardation represents a major concern for adolescents with perinatally acquired HIV,” comment the authors. “Half…were stunted at ART initiation and the prevalence of stunting remained high during adolescence.”

The authors believe the late initiation of HIV therapy, the development of HIV-related illnesses, chronic inflammation and malnutrition are all likely explanations for the high and persisting levels of stunting they observed. However, they were unable to provide a ready reason why boys remained more vulnerable to stunting. 

Glossary

wasting

Muscle and fat loss.

 

sample

Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

inflammation

The general term for the body’s response to injury, including injury by an infection. The acute phase (with fever, swollen glands, sore throat, headaches, etc.) is a sign that the immune system has been triggered by a signal announcing the infection. But chronic (or persisting) inflammation, even at low grade, is problematic, as it is associated in the long term to many conditions such as heart disease or cancer. The best treatment of HIV-inflammation is antiretroviral therapy.

middle income countries

The World Bank classifies countries according to their income: low, lower-middle, upper-middle and high. There are around 50 lower-middle income countries (mostly in Africa and Asia) and around 60 upper-middle income countries (in Africa, Eastern Europe, Asia, Latin America and the Caribbean).

low income countries

The World Bank classifies countries according to their income: low, lower-middle, upper-middle and high. While the majority of the approximately 30 countries that are ranked as low income are in sub-Saharan Africa, many African countries including Kenya, Nigeria, South Africa and Zambia are in the middle-income brackets. 

Adolescence is a key period for physical growth. Multiple studies have found growth deficiencies among adolescents with perinatally acquired HIV infection, especially among those living in low-income countries.

Dr Julie Jesson and her fellow researchers at the International epidemiology Databases to Evaluate AIDS (IeDEA) collaboration designed a study to describe growth evolution during adolescence and its associated factors among boys and girls with perinatally acquired HIV infection.

Their study sample included 8737 individuals who received care between 2003 and 2016 in sub-Saharan Africa, Asia-Pacific and Central and South America. Key inclusion criteria were treatment with ART, perinatally acquired HIV, entering HIV care before the age of ten years, at least one height measurement between the ages of ten and 16 years, and follow-up until at least the age of 14 years.

Growth was measured according to height-for-age, using World Health Organization child growth standards. It is expressed as a “Z” score (height-age Z score, or HAZ). Stunted growth was a score of -2 below the standard deviation, while severe stunting was a score of -3. Annual growth velocity (annual height gain in centimetres) and wasting (weight-for-height) were also assessed.

The median age at ART initiation was eight years, with 85% of the sample starting antiretrovirals after the age of five.

At the time HIV therapy was started, 50% of the sample had stunted growth, half of whom were severely stunted. Eighteen per cent had evidence of wasting. There was minimal difference in the prevalence of stunting or wasting between boys and girls at ART initiation.

Growth velocity reached a peak in boys and girls at the age of 13 and 11 years, respectively. After the age of 12 years, the height-age Z-score was higher for girls for boys. At 13 years of age, 51% of boys and 35% of girls were categorised as having stunted growth, a difference that persisted through to the age of 18 years (31% vs 15%).

“Children who spend their first years of life with HIV without ART may have chronic inflammation due to uncontrolled HIV, which can affect growth."

Several factors were associated with stunting. These included older age at the time of ART initiation, lower CD4 cell count and wasting. There was also some evidence that boys living in rural areas had poorer growth compared to adolescents receiving care in urban settings.

“Children who spend their first years of life with HIV without ART may have chronic inflammation due to uncontrolled HIV, which can affect growth,” note the authors. “The longer this exposure to uncontrolled HIV, the more adversely growth might be affected.”

Without HIV treatment, children will also be vulnerable to serious HIV-related illness, especially diarrhoea, pneumonia and tuberculosis, all of which can adversely affect growth. Many of the adolescents enrolled in the study were also vulnerable to malnutrition.

Jesson and colleagues also note that a large number of study participants would have had poor access to ART, entering care before guidelines recommended immediate treatment for all children. “With better access to paediatric care and earlier ART initiation…we would expect to observe lower rates of stunting at ART initiation and better catch-up growth during adolescence in the future,” they say. “However, stunting is still highly prevalent in most of the study settings in the general population and early access to ART initiation is not yet a reality in some sub-regions such as West and Central Africa.”

Jesson and colleagues were unable to offer firm explanations for why boys were more vulnerable to poor growth than girls and call for further research into this finding.