|Van Der Horst, Charles|
Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/13/2014
Publication Date: 4/1/2014
Publication URL: http://handle.nal.usda.gov/10113/59646
Citation: Flax, V.L., Bentley, M.E., Combs, G.F., Chasela, C.S., Kayira, D., Tegha, G., Kamwendo, D., Daza, E.J., Fokar, A., Kourtis, A.P., Jamieson, D.J., Van Der Horst, C.M., Adair, L.S. 2014. Plasma and breastmilk selenium in HIV-infected Malawian mothers are positively associated with infant selenium status but are not associated with maternal supplementations: Breastfeeding, Antiretrovirals, and Nutrition Study. American Journal of Clinical Nutrition. 99:950-956. Interpretive Summary: Selenium levels are typically low in HIV-infected individuals. Blood selenium levels can be increased by dietary supplementation, but whether this is true of breastmilk or of the selenium status of breastfed infants is unknown. These questions were addressed by supplementing HIV-infected Malawian mothers with a daily nutritional supplement containing either no selenium or 75 mcg (the RDA) of selenium. Linear regression techniques were used to determine the effects of the supplement on the selenium contents of maternal plasma and breastmilk, the association of breastmilk selenium concentration and infant plasma selenium for 24 weeks. The results showed that selenium supplementation did not affect maternal plasma or breastmilk Se. In fact, breastmilk selenium levels declined during lactation. The selenium intakes of nursing infants were estimated to decline similarly, from 10.2 µg/d at 2 weeks to 7.6 µg/d at 24 weeks.
Technical Abstract: Background: Low dietary selenium (Se) intake coupled with low plasma Se concentrations in HIV infection could result in inadequate breastmilk Se intake by exclusively breastfed infants of HIV-infected women. Objective: To test the effect of lipid-based nutrient supplements (LNS) containing 1.3 RDA of sodium selenite and anti-retroviral drugs (ARV) on maternal plasma and breastmilk Se. Design: HIV-infected Malawian mothers in the Breastfeeding, Antiretrovirals, and Nutrition study were randomized at delivery to: LNS, ARV, LNS-ARV, or control. In a sub-sample of 512 mothers and their uninfected infants, we measured plasma and breastmilk Se concentrations at 2 or 6 wk (depending on availability of infant samples) and 24 wk post-partum. Results: Mean maternal (81.1-86.1 ng/mL) and infant (55.6-60.7 ng/mL) plasma Se increased, while breastmilk Se levels declined (14.4-9.8 ng/mL) from 2 or 6 to 24 wk (all p<0.001). The direction of change in Se levels differed by baseline Se tertile. Low (ß=9.1, p<0.001) and mid (ß=20.8, p<0.001) baseline Se tertile were positively associated with change in maternal plasma or breastmilk Se from 2 or 6 to 24 wk. LNS and ARV were not associated with change in Se concentration. Higher maternal plasma and breastmilk Se were associated with higher infant plasma Se at 2 or 6 and 24 wk (p<0.001), regardless of study arm. Conclusions: Similar patterns of change in Se levels in breastmilk and infant plasma have been documented in non-HIV-infected populations and are probably physiological. The lack of Se supplementation effect is likely related to the form of Se used.