Therapeutic effects of oral zinc in acute and persistent diarrhea in children in developing countries: pooled analysis of randomized controlled trials.
BACKGROUND
Zinc deficiency is prevalent in children in developing countries. Supplemental zinc provides therapeutic benefits in diarrhea.


OBJECTIVE
We sought to measure the effect of supplemental zinc given with oral rehydration therapy during recovery from acute or persistent diarrhea.


METHODS
We conducted pooled analyses including all available published and unpublished randomized controlled trials of the effects of supplementary oral zinc in children aged <5 y with acute or persistent diarrhea. We used Cox survival regression analysis to evaluate the overall effect of zinc on continuation of diarrhea and possible differential effects in subgroups divided by sex, age, weight-for-height, and initial plasma zinc concentration. Dichotomous outcomes were analyzed by logistic regression. To assess the effects of excluding studies without original data from the pooled analyses, effect-size was estimated for all studies by using random-effects models.


RESULTS
Zinc-supplemented children had a 15% lower probability of continuing diarrhea on a given day (95% CI: 5%, 24%) in the acute-diarrhea trials and a 24% lower probability of continuing diarrhea (95% CI: 9%, 37%) and a 42% lower rate of treatment failure or death (95% CI: 10%, 63%) in the persistent-diarrhea trials. In none of the subgroup analyses were the 2 subgroups of each pair significantly different from each other; however, in persistent diarrhea there tended to be a greater effect in subjects aged <12 mo, who were male, or who had wasting or lower baseline plasma zinc concentrations.


CONCLUSIONS
Zinc supplementation reduces the duration and severity of acute and persistent diarrhea.
Bhutta
Z A
ZA
Aga Khan University Medical Centre, Karachi, Pakistan.
Bird
S M
SM
Black
R E
RE
Brown
K H
KH
Gardner
J M
JM
Hidayat
A
A
Khatun
F
F
Martorell
R
R
Ninh
N X
NX
Penny
M E
ME
Rosado
J L
JL
Roy
S K
SK
Ruel
M
M
Sazawal
S
S
Shankar
A
A
D000208:Acute Disease; D000284:Administration, Oral; D002675:Child, Preschool; D003906:Developing Countries; D003967:Diarrhea / Q000188:drug therapy*; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D016032:Randomized Controlled Trials as Topic; D015032:Zinc / Q000008:administration & dosage / Q000097:blood / Q000172:deficiency / Q000627:therapeutic use
D015032:Zinc