An evaluation of the haemoglobin cut-off for mild anaemia in Asians – analysis of multiple rounds of NHANES and NDNS
Jithin Sam Varghese, Tinku Thomas, Anura Kurpad
Journal: Indian Journal of Medical Research
Link: 10.4103/ijmr.IJMR_334_18
Submitted: March 2018
Review 1: September 2018
Accepted: November 2018
Background & objectives
The haemoglobin (Hb) cut-off is a single value for all populations. It is possible that different populations might have slightly different cut-off values, but this needs to be evaluated in healthy populations with low possibility of inadequate dietary intakes of haematopoietic nutrients.
Methods
This study examined Hb distributions of healthy White, Black, Mexican & Hispanic and Asian non-pregnant women belonging to from 9 rounds of the National Health and Nutrition Examination Survey (NHANES) and 2 rounds of National Diet and Nutrition Survey (NDNS), to check the existence of race-specific Hb cut-offs for mild anaemia, by standard statistical methods.
Results
The mean Hb of Blacks, Mexicans & Hispanics and Asians were lower than Whites, consistent with previous literature. The Hb cut-off for mild anaemia in Asians was lower, at 11.22 gm/dL.
Interpretation & conclusions
Using the Hb cut-off derived here in place of the WHO 12 gm/dL cut-off would result in a 17.9% decrease in prevalence of anaemia in India. This points to the need for re-examining race specific cut-off for mild anaemia, and points to the need for alternative methods, perhaps linked to risk of unhealthy outcomes.
"The field of nutrition, like other areas of science, has commonly used ‘race’ to describe research participants and populations, without the recognition that race is a social, not a biologic, construct....We recommend that biomedical researchers, especially those in the field of nutrition, abandon the use of racial categories to explain biologic phenomena but instead rely on a more comprehensive framework of ethnicity.."
- Duggan et al 2020 Am J Clin Nutr