Vitamin D and Zinc Deficiency in a Pediatric Population: A Retrospective Study

Abstract Background: Vitamin D and zinc are essential micronutrients with critical roles in immune regulation, bone health, and cellular function. Unfortunately, deficiencies in both nutrients are prevalent globally, particularly among pediatric populations. Methods: This retrospective study investigated the prevalence of vitamin D and zinc deficiencies in the pediatric population managed in either out-patient or in-patient setting in one private hospital in Hong Kong and to assess the association between these deficiencies with respiratory infections and growth parameters. Results: A retrospective analysis of 262 pediatric patients (less than 19 years old) revealed a high prevalence of abnormally low vitamin D levels (22.9% deficiency and 41.6% insufficiency) and zinc deficiency (37.0%), with 25.6% exhibiting combined deficiencies. Vitamin D and zinc levels were positively correlated ( r = 0.24, P < 0.001). Combined deficiencies were associated with an increased risk of pneumonia (odds ratios 4.5, 95% confidence interval 1.8–11.2, P = 0.001). Unfortunately, the deficiencies could not be predicted from anthropometric growth indicators such as weight, height, or body mass index percentile. Conclusions: Vitamin D insufficiency/deficiency and zinc deficiency are common in pediatric population. Screening for the deficiency of both vitamin D and zinc is indicated for children with pneumonia even in the absence of subnormal growth. Earlier detection and intervention through supplementation or dietary modifications would be beneficial in promoting the health of this otherwise healthy pediatric population and potentially reduce pneumonia recurrence.