Page 144 - 15Diarrhoeaandvomiting

Other therapies

compared with the placebo group (8.7%) (RR 1.7; 95% CI 1.4 to 2.2), although vomiting events
were equal among the two groups.
Five trials reported the mean duration of diarrhoea. The results of these trials are presented
according to participants’ age (Figure 8.4). One small trial 181 reported a statistically significant
reduction in the mean duration of diarrhoea for children given zinc compared with those given
placebo (WMD −31.2 hours; 95% CI −46.4 to −16.0 hours). Meta-analysis of all five trials
using the random effects model found no statistically significant difference in mean duration
of diarrhoea between those receiving zinc (n = 903) or placebo (n = 821) (WMD −4.4 hours;
95% CI −15.9 to 7.2 hours).
Four trials (n = 3168) reported the proportion of children with diarrhoea by day 7. Results are
presented according to participants’ age in Figure 8.5. Two trials 182,186 reported that statistically
significantly fewer children given zinc had diarrhoea by day 7 compared with those given
placebo. The first reported this finding in children aged between 6 and 35 months (RR 0.58;
95% CI 0.38 to 0.87) and the second in children aged between 3 and 36 months (RR 0.11;
95% CI 0.01 to 0.88). However, when the results of the four trials were pooled together, there
was no statistically significant difference in the proportion of children with diarrhoea by day 7
between those receiving zinc (n = 1568) or placebo (n = 1600) (RR 0.90; 95% CI 0.64 to 1.27).
Six trials reported outcomes for stool frequency. Four trials (n = 2135) reported the mean
number of stools per day. Results are presented according to participants’ age in Figure 8.6. Two
trials 177,181 reported that children given zinc had statistically significantly lower stool frequency
than those given placebo. The first trial made this finding in children aged between 6 and
35 months (WMD −2.00; 95% CI −3.61 to −0.39) and the second in children aged between 3
and 36 months (WMD −5.20; 95% CI −8.52 to −1.88). Pooled results of the four trials found
no statistically significant difference in the mean stool frequency between those receiving zinc
(n = 1056) or placebo (n = 1079) (WMD −0.32; 95% CI −0.8 to 0.17). However a statistically
significant reduction in stool frequency was seen in children aged over 6 months (two RCTs,
WMD −1.90; 95% CI −3.22 to −0.58).
Six trials reported results for vomiting. Four trials (n = 2475) reported the proportion of children
184
who vomited. Results are presented according to participants’ age in Figure 8.7. One trial
reported that statistically significantly more children given zinc had vomited compared with those
given placebo. This finding was reported for children seen in inpatients (RR 1.95; 95% CI 1.64
to 2.32) and outpatients (RR 2.53; 95% CI 2.04 to 3.13). The data from all four trials (n = 2475)
were combined in a meta-analysis that showed a statistically significant increase of vomiting
in children receiving zinc supplementations when compared with children receiving placebo
(RR 1.63; 95% CI 1.11 to 2.40).

Figure 8.4 Comparison of the effect of zinc versus placebo on the mean duration of diarrhoea

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