Abstract
Purpose :
Vitamin A deficiency (VAD) is a continuing public health problem among children and pregnant women of Nepal. We conducted a comparative cross-sectional study to assess skin carotenoid measurement as a rapid noninvasive screening tool for VAD in children and pregnant women.
Methods :
We enrolled 162 pregnant women and 164 children (8 to 12 years old) from three public hospitals in three ecological regions (Mountain, Hill and Terai) of Nepal in this study. Skin carotenoid levels were assessed noninvasively with reflection spectroscopy using the Veggie Meter® (Longevity Link Corporation, Salt Lake City, Utah, USA). The primary outcome was whether skin carotenoid measurement can successfully identify subjects with VAD. Detailed eye evaluations were conducted in subjects with low skin carotenoid scores (<150 RU) and those with symptomatic night blindness. Serum retinol and serum carotenoid levels were measured using high performance liquid chromatography (HPLC). Intra-class correlation coefficients were calculated. P values were considered significant if less than 0.05.
Results :
A total of 8.6% of pregnant women and 12.8% of children were VAD (serum retinol <200 ng/ml) even though only four had present or past ocular clinical signs of VAD. There was significant correlation of total skin carotenoids with serum retinol among the pregnant women (r= 0.255, p= 0.001) and children (r=0.253, p=0.001). There was significant correlation of skin carotenoids with serum carotenoids among the pregnant women (r=0.314, p <0.001) and children (r=0.510, p < 0.001). There was significant correlation of total serum carotenoids with serum retinol among the pregnant women (r= 0.447, p= 0.001) and children (r=0.530, p<0.001). When we performed initial statistical analysis using a cutoff of 200 RU, the Veggie Meter® detected VAD with 71.4% sensitivity and 66.0% specificity in pregnant women and with 71.4% sensitivity and 54.6% specificity in children.
Conclusions :
Although sensitivity and specificity were moderate for detecting VAD with the Veggie Meter®, skin carotenoid assessment using this rapid noninvasive portable device could still have immense value as a biomarker for high-risk VAD screening in Nepal and similar developing countries with limited access to laboratory measurement of serum vitamin A levels.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.