Among women in 60 low- and middle-income countries, the prevalence of body mass index (BMI) lower than 16 (the most severe category of adult malnutrition) was about 2 percent, and was associated with poverty and low education levels, according to a study in the JAMA. The prevalence of this level of BMI did not decrease over time in most countries studied.
In 1998, the United Nations sought a method to quantify the population prevalence of severe chronic undernutrition, and designated a BMI lower than 16 as a definition of severe chronic energy deficiency, which is associated with substantial illness, increased mortality, and poor maternal-fetal outcomes such as low-birth-weight newborns. Little is known about the prevalence and distribution of BMI lower than 16 in low- and middle-income countries (LMIC). Fahad Razak, M.D., M.Sc., of the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, and colleagues analyzed data composed of nationally representative surveys from 1993 through 2012 from the Demographic and Health Surveys Program. Data from women 20 through 49 years of age from 60 LMIC (n = 500,761) and a subset of 40 countries with repeated surveys (n = 604,144) were examined.
Among countries examined, the prevalence of BMI lower than 16 was 1.8 percent, with the highest prevalence in India (6.2 percent), followed by Bangladesh (3.9 percent), Madagascar (3.4 percent), Timor-Leste (2.9 percent), Senegal (2.5 percent), and Sierra Leone (2.2 percent). Six countries had prevalences lower than 0.1 percent (Albania, Bolivia, Egypt, Peru, Swaziland, and Turkey).
The prevalence of BMI lower than 16 was highest in women with no education (1.8 percent) vs those with secondary education or higher (0.51 percent) and higher for those residing in rural areas (1.3 percent) compared with those residing in urban areas (0.50 percent). The prevalence of BMI lower than 16 was 0.43 percent for women in the highest wealth quintile, and 1.5 percent for women in the lowest wealth quintile. Among the 24 of 39 countries with repeated surveys, there was no decrease in prevalence. In Bangladesh and India, rates were declining.
"The 60 LMIC studied here represent an estimated 3 billion individuals. There are 2 major findings. First, using the most recently available nationally representative data on a large range of LMIC, BMI lower than 16 remains a critically important public health entity. BMI lower than 16 was associated with poverty and low education. Second, the prevalence of BMI lower than 16 was not decreasing in most countries. The prevalence and total population burden of individuals with BMI lower than 16 remains high globally, and if prevalence estimates are generalizable, more than 18 million women are affected in the countries studied," the authors write.
"The finding of a large and, in some countries, persistent burden of individuals with BMI lower than 16 supports the need for further study of why mortality rates are increased and supports the value of intervention studies to examine whether mortality can be reduced."
The researchers add that nutritional supplementation over a short term has shown some encouraging effects among those with BMI lower than 16, but many questions remain unanswered about potentially increased long-term cardiovascular and chronic disease risk when chronic nutritional deprivation is reversed in adulthood.