The effect of vitamin D supplementation on vitamin D status and parathyroid function in elderly subjects.
Vitamin D deficiency is common in the elderly and may lead to secondary hyperparathyroidism, cortical bone loss, and hip fractures. The effect of vitamin D supplementation for 1 yr was studied in 72 people living in a nursing home and 70 people living in an aged people's home. The subjects were randomized into 3 groups: control, and 400 or 800 IU vitamin D3/day. The initial vitamin D status of each subject was classified as deficient or borderline [serum 25-hydroxyvitamin D (25OHD) less than 30 nmol/L] in 79% and adequate (serum 25OHD greater than or equal to 30 nmol/L) in 21%. Serum 25OHD concentrations increased about 3-fold in both groups receiving vitamin D supplementation. Serum 1,25-dihydroxyvitamin D [1,25-(OH)2D] concentrations increased slightly but significantly, and the increase was inversely related to the initial serum 25OHD concentration. Serum intact PTH-(1-84) concentrations decreased about 15% during supplementation in both nursing home and aged people's home residents, whereas serum osteocalcin significantly decreased in the nursing home residents only. We conclude that a vitamin D3 supplement of 400 IU/day adequately improves vitamin D status in elderly people and increases 1,25-(OH)2D concentrations in those with vitamin D deficiency. Supplementation decreases parathyroid function and may depress bone turnover to some degree.
Lips
P
P
Department of Endocrinology, Academisch Ziekenhuis Vrije Universiteit, Amsterdam, The Netherlands.
Wiersinga
A
A
van Ginkel
F C
FC
Jongen
M J
MJ
Netelenbos
J C
JC
Hackeng
W H
WH
Delmas
P D
PD
van der Vijgh
W J
WJ
D000368:Aged; D000369:Aged, 80 and over; D002118:Calcium / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D005260:Female; D006707:Homes for the Aged; D006801:Humans; D007668:Kidney / Q000187:drug effects; D008297:Male; D009735:Nursing Homes; D010280:Parathyroid Glands / Q000187:drug effects*; D011897:Random Allocation; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood; D014808:Vitamin D Deficiency / Q000188:drug therapy / Q000378:metabolism
D014807:Vitamin D; D002784:Cholesterol; D002118:Calcium