RESUMEN
BACKGROUND: Vitamin D plays an important role in the mineral and bone disorder seen in chronic kidney disease (CKD). Deficiency of 25-hydroxyvitamin D (25OHD) is highly prevalent in the adult CKD population. METHODS: The prevalence and determinants of 25OHD deficiency (defined as a level <20 ng/ml) were examined longitudinally in 506 children in the CKiD cohort. Predictors of secondary hyperparathyroidism and the determinants of 1,25-dihydroxyvitamin D (1,25(OH)2D) levels were also evaluated. RESULTS: Deficiency of 25OHD was observed in 28 % of the cohort at enrollment. Significant predictors of 25OHD deficiency were older age, non-white race, higher body mass index, assessment during winter, less often than daily milk intake, non-use of nutritional vitamin D supplement and proteinuria. Lower values of glomerular filtration rate (GFR), serum 25OHD, calcium and higher levels of FGF23 were significant determinants of secondary hyperparathyroidism. Lower GFR, low serum 25OHD, nephrotic-range proteinuria, and high FGF23 levels were significant determinants of serum 1,25(OH)2 D levels. CONCLUSIONS: Deficiency of 25OHD is prevalent in children with CKD and is associated with potentially modifiable risk factors such as milk intake, nutritional vitamin D supplement use, and proteinuria. 25OHD deficiency is a risk factor for secondary hyperparathyroidism and decreased serum 1,25(OH)2D in children with CKD.
Asunto(s)
Insuficiencia Renal Crónica/epidemiología , Deficiencia de Vitamina D/epidemiología , Vitamina D/análogos & derivados , Adolescente , Factores de Edad , Animales , Biomarcadores/sangre , Índice de Masa Corporal , Niño , Preescolar , Suplementos Dietéticos , Femenino , Factor-23 de Crecimiento de Fibroblastos , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/diagnóstico , Hiperparatiroidismo Secundario/epidemiología , Lactante , Estudios Longitudinales , Masculino , Leche , América del Norte/epidemiología , Estado Nutricional , Hormona Paratiroidea/sangre , Prevalencia , Pronóstico , Estudios Prospectivos , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Medición de Riesgo , Factores de Riesgo , Estaciones del Año , Factores de Tiempo , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/diagnóstico , Deficiencia de Vitamina D/terapiaRESUMEN
OBJECTIVES: To determine the prevalence of 25-hydroxyvitamin D (25[OH]D) deficiency and associations between 25(OH)D deficiency and cardiovascular risk factors in children and adolescents. METHODS: With a nationally representative sample of children aged 1 to 21 years in the National Health and Nutrition Examination Survey 2001-2004 (n = 6275), we measured serum 25(OH)D deficiency and insufficiency (25[OH]D <15 ng/mL and 15-29 ng/mL, respectively) and cardiovascular risk factors. RESULTS: Overall, 9% of the pediatric population, representing 7.6 million US children and adolescents, were 25(OH)D deficient and 61%, representing 50.8 million US children and adolescents, were 25(OH)D insufficient. Only 4% had taken 400 IU of vitamin D per day for the past 30 days. After multivariable adjustment, those who were older (odds ratio [OR]: 1.16 [95% confidence interval (CI): 1.12 to 1.20] per year of age), girls (OR: 1.9 [1.6 to 2.4]), non-Hispanic black (OR: 21.9 [13.4 to 35.7]) or Mexican-American (OR: 3.5 [1.9 to 6.4]) compared with non-Hispanic white, obese (OR: 1.9 [1.5 to 2.5]), and those who drank milk less than once a week (OR: 2.9 [2.1 to 3.9]) or used >4 hours of television, video, or computers per day (OR: 1.6 [1.1 to 2.3]) were more likely to be 25(OH)D deficient. Those who used vitamin D supplementation were less likely (OR: 0.4 [0.2 to 0.8]) to be 25(OH)D deficient. Also, after multivariable adjustment, 25(OH)D deficiency was associated with elevated parathyroid hormone levels (OR: 3.6; [1.8 to 7.1]), higher systolic blood pressure (OR: 2.24 mmHg [0.98 to 3.50 mmHg]), and lower serum calcium (OR: -0.10 mg/dL [-0.15 to -0.04 mg/dL]) and high-density lipoprotein cholesterol (OR: -3.03 mg/dL [-5.02 to -1.04]) levels compared with those with 25(OH)D levels > or =30 ng/mL. CONCLUSIONS: 25(OH)D deficiency is common in the general US pediatric population and is associated with adverse cardiovascular risks.
Asunto(s)
Deficiencia de Vitamina D/epidemiología , Vitamina D/análogos & derivados , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Encuestas Nutricionales , Prevalencia , Factores de Riesgo , Estados Unidos/epidemiología , Deficiencia de Vitamina D/complicaciones , Adulto JovenRESUMEN
Carnitine is an amino acid derivative that has a key role in the regulation of fatty acid metabolism and ATP formation. Carnitine deficiency has been described in various conditions, including chronic kidney disease (CKD) and end stage renal disease (ESRD). The deficiency of this micronutrient is postulated to lead to adverse effects across multiple organ systems. There is a paucity of information on carnitine deficiency and its effects in the pediatric CKD and ESRD populations. Currently, there is no evidence supporting the routine use of carnitine supplementation in children with ESRD. In this article, we review the pathophysiology, pharmacokinetics and the potential effects of levo-carnitine supplementation with a focus on the pediatric CKD and ESRD populations. Finally, potential future directions of research are discussed.