Impact of Zinc Supplementation in Low Birth Weight Infants on Severe Morbidity, Mortality and Zinc Status: A Randomized Controlled Trial

A double blind, randomized, placebo controlled trial is being conducted in which the unit of randomization is 14-28 days old infants. Infants in the intervention group receive 1 RDA of elemental zinc compared to placebo in the control group, from the day of enrollment till 12 months of age.

Infants for enrollment are being identified through daily screening of newborns in two hospitals. Eligible infants are visited at home for enrollment when aged 14-28 days. The mother is trained in supplement administration. A total of 2000 infants will be enrolled.

Infants in the intervention group are being administered a dispersible tablet daily containing 1 RDA of elemental zinc (5 mg elemental zinc per day in infants aged 14 days to 6 months and 10 mg per day for infants older than 6 months) daily till 12 months of age. The placebo contains plain glucose but is similar in taste, color and consistency to the zinc tablet. The tablets are packaged in strips containing 15 tablets each.

Monthly supplies of the supplement are given to the caregiver to be kept at home. The supplement is administered by the caregiver (usually the mother) herself and the method of administration is taught at the time of enrollment. At the end of every four weeks the monitor collects the strips for the previous month and records the supplement intake for the previous month by examining the strips and querying the caregiver.

Three monthly morbidity visits are conducted by a field investigator to obtain information on the hospitalizations and their causes in the last 3 months, healthcare provider visits in the last 1 month, illnesses for which these were made and severity of these illnesses, diarrhea and respiratory morbidity in the previous 24 hours, week and month. If the infant has been hospitalized in the last 3 months, a hospitalization form is filled to ascertain the reason for hospitalization. In case of deaths, an interview is conducted with the caregiver and a verbal autopsy form is filled.

Blood specimens for estimation of plasma zinc, copper and ferritin are being obtained in 15% randomly selected children at baseline and at end study.

Weights and lengths are being obtained in a subset of children at birth, 3, 6, 9 and 12 months.

Inclusion criteria

• Infants aged 14 to 28 days born after 37 weeks of gestation and weighing less than or equal to 2.5 kg at birth (<10th percentile of the National Center for Health Statistics [NCHS] median birth weight)
• Either sex
• Resides within 7 km of the hospital

Exclusion criteria

• Likely to leave the area of residence within 6 months of enrollment
• Congenital malformations, congenital heart disease, metabolic disorders, renal diseases, etc.
• Non consent for participation
• Illness requiring hospitalization
• Twins
• Preterm