Purpose: We have reported a new, non-invasive technology for the assessment of population Vitamin A status among young children (AJCN 61:1076-1082; IOVS 36:8863 abstr.) We wished to determine if our device would detect impaired dark adaptation among pregnant women in an area where vitamin A deficient nightblindness is common. Methods: 102 pregnant Nepali and 100 nonpregnant American women of similar (23.6 vs 24.6 yrs, p = 0.3) ages underwent testing of dark-adapted visual and pupillary thresholds according to a previously reported protocol. Half of the Nepali women were randomized to vitamin A supplementation and half placebo. Results: More than 97% of subjects in both groups completed all testing. Mean pupillary (-1.31 ± 0.38 vs -1.84 ± 0.51 log candela/m2, P < 0.0001) and visual (-4.41 ± 0.46 vs -4.84 ± 0.35 log candela/m2, P < 0.0001) dark adaptation thresholds were significantly higher (less sensitive dark vision) for the Nepali women. Post-partum follow-up testing and results of non-intervened pregnant women will also be presented. Conclusion: Pupillary and visual dark adaptation testing are further validated as a non-invasive, practical and highly effective technology for population assessment of vitamin A status.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience