The study focused on school-age children and teenagers, ages 5 to 19. But researchers also validated the method in children older than 2 years, and adults up to 25.
A bicep measurement is simpler, faster and as accurate or more so than the height and weight measurements required for an assessment of body mass index, or BMI, researchers said. BMI is the current World Health Organization-endorsed standard to quickly assess a child’s health in certain portions of the world.
This is critical in places where malnourishment and illness, particularly among HIV-infected children, are rampant. The use of this measurement method, called “mid-upper arm circumference,” or MUAC, can help schools and public health authorities target those in need of nutritional services and medical treatment.
MUAC directly measures muscle and fat, which are the body’s main nutritional stores. Bone circumference, researchers said, is minor at the bicep and will not throw off the calculation, making the bicep an ideal spot to take a measurement assessing nutrition and health.
Lead researcher Lazarus Mramba, Ph.D., a statistician in UF’s College of Medicine, said it can be extremely challenging for clinicians trying to measure a child’s height and weight, and errors are easily introduced. This is especially true in countries where medical services are often overtaxed.
“Can you imagine measuring a 3-year-old?” Mramba said. “The child has to lie on a scale. They have to stretch the legs so they can get the height. The child might be moving or kicking out. You have two measurements to put together before you come up with BMI. Those are two potential errors that can be introduced. But if you are only measuring one thing, there is only one potential error.”
MUAC has been around for years. But rigorously examined data validating its accuracy in developing world populations with high rates of malnutrition have been absent until this study, Mramba said. Clinicians have been wary of using the method in these groups because of the lack of research demonstrating its accuracy when compared with BMI.
Mramba’s study assessed the method’s accuracy by examining medical records of 685 HIV-infected school-age children, adolescents and young adults ages 2 to 25 years from Uganda and Zimbabwe. Researchers also evaluated 1,741 children from Kenya who were at increased risk of death after a hospitalization. About 4 percent of the Kenyan group were HIV infected.
All groups had undergone both BMI and MUAC measurements.
Mramba found that MUAC was at least as accurate as BMI for the group in Uganda and Zimbabwe, and more accurate in predicting survival of the Kenyan group.
The results, researchers said, “confirm that the new growth reference is valid for assessing African school-age children and adolescents.”
While researchers validated MUAC for ages 2 to 25 years in Africa, the study itself focused on the 5- to 19-year-old age group to exactly match for comparison purposes a BMI study conducted earlier by WHO.
Mramba worked in collaboration with researchers in Great Britain and Kenya, including the Kenya Medical Research Institute – Wellcome Trust Research Programme.
“MUAC is a very reliable and simple method that should be used,” said Mramba. “It helps identify individuals at risk of increased mortality so you can easily target them with direct financial resources and medical services. Then it’s, let’s get some funding for them. Let’s make sure to get them some food. Let’s make sure they get some medication. Let’s make sure we put all our effort there to save a life.”