Poster Topical Area: Global Nutrition
Location: Hall D
Poster Board Number: 597
Background: There is limited evidence regarding the safety of untargeted daily iron supplementation in women, especially in predominantly iron-replete populations where genetic hemoglobinopathies are common. Iron is a catalyst for oxidative stress, and excess iron can cause free radical formation, cellular damage, and increased susceptibility to pathogen growth.
Objective: We measured leukocyte telomere length, a marker of oxidative cellular damage and aging, in a predominantly anemic yet iron-replete population of non-pregnant Cambodian women (18-45 y) who were supplemented with daily oral iron for 12-wk.
Methods: In the double-blind randomized trial, women received 60 mg of elemental iron as ferrous sulphate (n=201) or a placebo (n=200) for 12-wk. Fasting blood was collected at baseline and endline from women in 26 villages in Kampong Chhnang. Relative leukocyte telomere length (LTL) was measured in extracted DNA using real-time qPCR, expressed as a ratio of the telomeric DNA (T) normalized to a single-copy nuclear gene (S), yielding the T/S ratio. We assessed the baseline to endline change in LTL at 12-wk, adjusting for age and village clusters.
Results: At baseline, 78% of women were iron-replete (n=314/401 based on ferritin >15 µg/L) and 75% (n=300/401) had some form of a hemoglobinopathy (namely, hemoglobin E and a-thalassemia variants). Data were available at 12-wk for n=376 women. Baseline mean ± SD LTL was 7.19 ± 0.97; Endline mean ± SD LTL in the Fe and placebo group was 7.11 ± 1.04 and 7.16 ± 0.93, respectively. The age- and village cluster-adjusted mean change in LTL at 12-wk was not significantly different in the Fe (n=190) and placebo (n=186) groups (ß-coefficient: -0.051 [95% CI: -0.182, 0.080]; P=0.45). Further, no differences were observed among Fe and placebo groups in iron-replete women (n=291, ß-coefficient: -0.041 [95% CI: -0.189, 0.108]; P=0.59) and among those with a hemoglobinopathy (n=280, ß-coefficient: -0.041 [95% CI: -0.192, 0.109]; P=0.59).
Conclusions: Daily oral iron for 12-wk was not associated with a statistically or clinically significant decrease in LTL in our study population. Other biomarkers of potential harm should be assessed in future research, in order to inform the safety of the WHO policy for untargeted iron supplementation for non-pregnant women worldwide.
University of British Columbia
Vancouver, British Columbia, Canada