ZINC SUPPLEMENTATION - EFFECTS ON THE GROWTH AND MORBIDITY OF UNDERNOURISHED JAMAICAN CHILDREN

Objective: We investigated whether there was a growth or morbidity res ponse to zinc supplementation. Design: The study was randomized, place bo-controlled, and double-blind. Setting: Children were recruited at c linics in Kingston, Jamaica, and supplemented at home. Subjects: Child ren selected were singletons aged 6-24 months, and stunted ( < -2.0 s. d. length for age, NCHS references). They were stratified by sex and a ge and randomly assigned to receive zinc supplement(n = 31) or placebo (n = 30), Four children were excluded because of hospitalization; all others had all measurements. Adequately nourished children (n = 24) w ere recruited from a well-baby clinic. Interventions: The supplement p rovided 5 mg elemental zinc in a syrup daily for 12 weeks. the placebo comprised the syrup only. Main outcome measures: Caretakers were inte rviewed to obtain social background data, number of clinic visits and hospitalizations, Anthropometric measurements were done on enrolment, and after 6 weeks, 12 weeks and 12 months. Children's health was deter mined by weekly questionnaire to caretakers of the undernourished grou ps during the supplementation period. ResuIts: The supplemented and pl acebo groups were similar on enrolment. The adequately nourished child ren were from significantly better socio-economic circumstances. Mean initial hair zinc content was 5.5 +/- 4.8 mu mol/g (supplemented group ) and 6.7 +/- 12.1 mu mol/g (placebo)(n.s.). Regression analyses showe d that there were no significant effects of supplementation on length, height or head circumference, nor on the incidence of any morbidity s ymptom. Mean duration of the episodes was significantly shorter for sk in rashes in the supplemented group compared with the control group (A NCOVA, P = 0.02), and longer far vomiting (P = 0.02). The incidence of hospitalization was significantly greater in the control group (Fishe r's exact test, P = 0.02). Conclusions: Zinc supplementation reduced t he hospitalizations which probably reflect severity of morbidity, but did not improve growth.