Vitamin D & Lipid Abnormalities
Low vitamin D levels have been associated with many risk factors for cardiovascular diseases. In addition to insulin resistance and hypertension, hypovitaminosis D has been associated with altered lipid profile in adults. Vitamin D is thought to be essential for maintaining adequate levels of ApoA-I, a major component of HDL cholesterol. Individuals with high 25(OH)D concentrations have the highest plasma ApoA-I concentrations, and there is a positive correlation between 25(OH)D and serum HDL cholesterol concentrations.[91,92]
In 3577 adolescents, aged 12–19 years, from the NHANES 2001–2004 survey, there was a higher adjusted odds ratio for those in the lowest (<15 ng/ml) compared with the highest quartile (>26 ng/ml) of 25(OH)D for low HDL cholesterol 1.54 (0.99 –2.39); hypertriglyceridemia 1.00 (0.49 –2.04); and the metabolic syndrome 3.88 (1.57–59.58). In a study of 217 obese children, lower HDL cholesterol levels were associated with lower levels of 25(OH)D. Our analysis of data from NHANES 2001–2004 found children with 25(OH)D deficiency (<15 ng/ml) to have lower HDL cholesterol levels (OR: -3.03 [-5.02 to -1.04]; p = 0.004) when compared with those with levels below 30 ng/ml.
Vitamin D, Infections & Asthma
Vitamin D has been shown to have important functions in innate immunity at the systemic and cellular level. The association between rickets, low vitamin D levels and infections has long been recognized and was recently reviewed. A recent case–control study from Canada showed that kids who had acute lower respiratory infections and were admitted to the intensive care unit were more likely to have low 25(OH)D levels than other children with lower respiratory infections and control patients without infections. A retrospective analysis of vitamin D supplementation use and urinary tract infections in infants revealed that infants who received vitamin D and were formula fed had a higher risk of developing a urinary tract infection. However, there is some controversy surrounding this report.
Evidence of a link between low vitamin D levels, intake and asthma and other allergic conditions has been emerging. A study of 1669 children in Finland correlated lower maternal vitamin D intake during pregnancy with a higher risk of asthma and allergic rhinitis in their offspring at 5 years of age. Other studies have found similar[99,100] and divergent results, suggesting the need for further research in this field.
Pediatr Health. 2010;4(1):89-97. © 2010 Future Medicine Ltd.
Cite this: Low Levels of 25-hydroxyvitamin D in the Pediatric Populations: Prevalence and Clinical Outcomes - Medscape - Feb 01, 2010.