 Nocturnal haemoglobin oxygen saturation variability is associated with vitamin C deficiency in Tanzanian children with sickle cell anaemia..pdf | [Nocturnal haemoglobin oxygen saturation variability is associated with vitamin C deficiency in Tanzanian children with sickle cell anaemia.] | 89 kB |
Nocturnal haemoglobin oxygen saturation variability is associated with vitamin C deficiency in Tanzanian children with sickle cell anaemia.
Acta Paediatr. 2011 Apr ;100(4):594-7. Epub 2010 Nov 23. PMID: 21091961
London School of Hygiene&Tropical Medicine, London, UK. This email address is being protected from spambots. You need JavaScript enabled to view it.
AIM: To compare pulse oximetry in children with sickle cell anaemia (SCA) and controls and test the hypothesis that vitamin C deficiency (VCD;<11.4μmol/L) is associated with nocturnal haemoglobin oxygen desaturation in SCA.
METHODS: We undertook nocturnal and daytime pulse oximetry in 23 children with SCA (median age 8 years) with known steady-state plasma vitamin C concentrations and 18 siblings (median 7 years).
RESULTS: Median nocturnal delta 12 s index (delta12 s), a measure of haemoglobin oxygen saturation (SpO(2)) variability, was 0.38 (interquartile range 0.28-0.51) in SCA and 0.35 (0.23-0.48) in controls, with 9/23 and 6/18, respectively, having a delta12 s>0.4, compatible with obstructive sleep apnoea (OSA). Eleven of twenty-three with SCA had VCD; logged vitamin C concentrations showed a 66% decrease per 0.1 unit increase in delta12 s ([95% CI -86%, -15%]; p=0.023) and delta12 s>0.4 was associated with VCD (odds ratio 8.75 [1.24-61.7], p=0.029). Daytime and mean nocturnal SpO(2) were lower in SCA but there was no association with vitamin C.
CONCLUSION: Obstructive sleep apnoea (OSA), detected from nocturnal haemoglobin oxygen saturation variability, is common in Tanzanian children and associated with vitamin C Deficiency in SCA. The direction of causality could be determined by comparing OSA treatment with vitamin C supplementation.
