TY - JOUR
T1 - Vitamin D status in kidney transplant patients
T2 - need for intensified routine supplementation
AU - Ewers, Bettina
AU - Gasbjerg, Ane
AU - Moelgaard, Christian
AU - Frederiksen, Anne Mette
AU - Marckmann, Peter
PY - 2008/2/1
Y1 - 2008/2/1
N2 - BACKGROUND: A high prevalence of vitamin D insufficiency has been found in the general population and in patients with chronic kidney disease. OBJECTIVE: The aim was to examine vitamin D status and determinants and metabolic correlates of serum 25-hydroxyvitamin D in a population of adult Danish kidney transplant patients. DESIGN: This was a cross-sectional study of 173 adult kidney transplant patients with a mean (+/-SD) age of 53.4 +/- 11.7 y and a median graft age of 7.4 y (interquartile range: 3.3-12.7 y). Serum concentrations of intact parathyroid hormone (S-PTH), 25-hydroxyvitamin D [S-25(OH)D], and 1,25-dihydroxyvitamin D [S-1,25(OH)(2)D] were measured. Dietary and supplementary intake of vitamin D, avoidance of solar ultraviolet B exposure, and selected lifestyle factors were assessed in a subgroup (n = 97). RESULTS: Fifty-one percent of the patients had vitamin D insufficiency [S-25(OH)D 40-75 nmol/L], and an additional 29% had moderate-to-severe vitamin D deficiency [S-25(OH)D < or = 39 nmol/L]. In multiple regression analysis, sun avoidance (negative association) and vitamin D supplementation (positive association) were independent determinants of S-25(OH)D concentrations. Low S-25(OH)D concentrations were associated with 1) increased S-PTH concentrations (P = 0.0002), independently of S-1,25(OH)(2)D concentrations, and 2) decreased S-1,25(OH)(2)D concentrations (P = 0.002), independently of graft function. CONCLUSIONS: Hypovitaminosis D is common among Danish kidney transplant patients and is associated with reduced concentrations of S-1,25(OH)(2)D and increased S-PTH concentrations. Sun avoidance and vitamin D supplementation are important determinants of vitamin D status. The observed hypovitaminosis D might be corrected by intensified routine vitamin D supplementation as opposed to the current supplementation practice.
AB - BACKGROUND: A high prevalence of vitamin D insufficiency has been found in the general population and in patients with chronic kidney disease. OBJECTIVE: The aim was to examine vitamin D status and determinants and metabolic correlates of serum 25-hydroxyvitamin D in a population of adult Danish kidney transplant patients. DESIGN: This was a cross-sectional study of 173 adult kidney transplant patients with a mean (+/-SD) age of 53.4 +/- 11.7 y and a median graft age of 7.4 y (interquartile range: 3.3-12.7 y). Serum concentrations of intact parathyroid hormone (S-PTH), 25-hydroxyvitamin D [S-25(OH)D], and 1,25-dihydroxyvitamin D [S-1,25(OH)(2)D] were measured. Dietary and supplementary intake of vitamin D, avoidance of solar ultraviolet B exposure, and selected lifestyle factors were assessed in a subgroup (n = 97). RESULTS: Fifty-one percent of the patients had vitamin D insufficiency [S-25(OH)D 40-75 nmol/L], and an additional 29% had moderate-to-severe vitamin D deficiency [S-25(OH)D < or = 39 nmol/L]. In multiple regression analysis, sun avoidance (negative association) and vitamin D supplementation (positive association) were independent determinants of S-25(OH)D concentrations. Low S-25(OH)D concentrations were associated with 1) increased S-PTH concentrations (P = 0.0002), independently of S-1,25(OH)(2)D concentrations, and 2) decreased S-1,25(OH)(2)D concentrations (P = 0.002), independently of graft function. CONCLUSIONS: Hypovitaminosis D is common among Danish kidney transplant patients and is associated with reduced concentrations of S-1,25(OH)(2)D and increased S-PTH concentrations. Sun avoidance and vitamin D supplementation are important determinants of vitamin D status. The observed hypovitaminosis D might be corrected by intensified routine vitamin D supplementation as opposed to the current supplementation practice.
KW - Adult
KW - Aged
KW - Calcium, Dietary
KW - Cross-Sectional Studies
KW - Denmark
KW - Dietary Supplements
KW - Female
KW - Humans
KW - Kidney Transplantation
KW - Life Style
KW - Male
KW - Middle Aged
KW - Prevalence
KW - Regression Analysis
KW - Sunlight
KW - Vitamin D
KW - Vitamin D Deficiency
M3 - Journal article
C2 - 18258635
SN - 0002-9165
VL - 87
SP - 431
EP - 437
JO - American Journal of Clinical Nutrition
JF - American Journal of Clinical Nutrition
IS - 2
ER -