Impact of Malnutrition on Pupillary Responses in Pediatric Population

Abstract

Purpose : To investigate the effect of nutritional status on pupillary responses in children aged 5 to 18 years. Methods : This cross-sectional study comprised 92 eyes of malnourished children and 80 eyes of age- and gender-matched healthy children based on BMI Z-score. Serum ferritin, hemoglobin, serum 25-hydroxyvitamin D, and vitamin B12 levels were recorded. Pupillary responses were taken using Sirius topography (CSO, Italy) with the automated pupillometry function. Static pupillometry consisted of pupil diameters at scotopic, mesopic, and photopic luminances. In dynamic pupillometry, the mean pupil dilation speed at the 10th second was calculated by dividing the distance by time in each 0.2 s period. Results : No significant difference was observed between the groups regarding age, gender, visual acuity, and spherical equivalent (p > 0.05). Mean hemoglobin, serum ferritin, serum 25-hydroxyvitamin D, and vitamin B12 levels were lower in malnourished children than healthy children (p < 0.001). The malnutrition group had lower mean pupil diameters under all luminance and higher speed of pupil dilation compared to the control group (p < 0.05). While malnutrition subgroups were similar in terms of pupil diameters under all luminance (p > 0.05), the speed of pupil dilation was significantly different between the groups (p = 0.024). BMI z-score was positively correlated with mesopic and photopic pupil diameter but also negatively correlated with the speed of pupil dilation (p < 0.05). Conclusion : Malnourished children have smaller pupil diameters and higher speed of pupil dilation than healthy controls, indicating an autonomic impairment.