Vitamin D Deficiency in Dengue Hemorrhagic Fever and Dengue Shock Syndrome among Sri Lankan Children: A Case-Control Study

INTRODUCTION: Dengue fever is a vector-borne disease associated with a significant public health impact. The clinical picture ranges from undifferentiated fever to more severe forms such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Compared to healthy controls, we explored the likelihood of having vitamin D deficiency (VDD) among children with severe dengue infection. METHODS: This case-control study compared hospitalized children (2 months to 12 years) with DHF and DSS with radiologically confirmed plasma leak with age-matched healthy controls. The association of 25-hydroxy vitamin D [25(OH)D] level, age, sex, and socioeconomic status with DHF/DSS was assessed using univariate and multivariate logistic regression. RESULTS: Forty children with DHF/DSS were compared with 52 healthy controls. Mean (SD) age was 8.8 (2.9) years and 7.9 (3.7) years among cases and controls, respectively. Most (n = 28, 70%) had DHF. In multivariate logistic regression, the likelihood of having VDD [25(OH)D < 20 ng/mL] was 3.6 times higher in cases compared to controls (Odds Ratio (OR): 3.65, 95% Confidence Interval (CI): 1.461, 9.102, p=0.006). When serum 25(OH)D was used as a continuous independent variable, the strength of the association between DHF/DSS and serum 25(OH)D was weak but statistically significant; the likelihood of having DHF/DSS is 0.94 times less with 1 ng/mL increase in serum 25(OH)D (OR: 0.940, 95% CI: 0.887, 0.995, p=0.03). CONCLUSION: The present study suggests that the likelihood of having VDD among children with DHF/DSS is higher than that in their healthy counterparts. Thus, further studies are critical in confirming whether vitamin D repletion is beneficial in preventing severe forms of dengue in the quest to reduce the morbidity and mortality associated with dengue infection.