Associations of serum 25-hydroxyvitamin D and vitamin D receptor polymorphisms with dengue severity in hospitalized Vietnamese children.

OBJECTIVES

To investigate the associations of serum 25-hydroxyvitamin D (25(OH)D) concentrations and vitamin D receptor (VDR) polymorphisms with dengue severity in hospitalized Vietnamese children.

METHODS

This cross-sectional study included 190 children aged ≤16 years with laboratory-confirmed dengue admitted to Ca Mau Obstetrics and Pediatrics Hospital, Vietnam. Disease severity was classified according to the World Health Organization 2009 criteria. Serum 25(OH)D concentrations were measured, and four VDR polymorphisms (FokI, BsmI, ApaI, and TaqI) were genotyped. Associations with severe dengue were assessed using univariable and multivariable logistic regression.

RESULTS

Thirty-two children (16.8%) had severe dengue. Median serum 25(OH)D concentrations were lower in children with severe dengue than in those with non-severe dengue (21.26 vs 26.65 ng/mL; P = 0.002). Higher serum 25(OH)D concentration remained associated with lower odds of severe dengue after adjustment for age group, sex, and IgG seropositivity (adjusted odds ratio = 0.921 per 1 ng/mL increase; 95% confidence interval, 0.855-0.992; P = 0.029). No significant associations were detected between the four VDR polymorphisms and dengue severity.

CONCLUSION

Lower serum 25(OH)D concentrations were associated with severe dengue, whereas the investigated VDR polymorphisms were not. Prospective multicenter studies are needed to clarify temporality and causality.