Seniors with poorly functioning kidneys had lower levels of vitamin D
Vitamin D deficiency in elderly women in nursing homes:
investigation with consideration of decreased activation function from the kidneys.
J Am Geriatr Soc. 2012 Feb;60(2):251-5. doi: 10.1111/j.1532-5415.2011.03826.x. Epub 2012 Jan 27.
Terabe Y, Harada A, Tokuda H, Okuizumi H, Nagaya M, Shimokata H.
Department of Orthopedic Surgery, National Center for Geriatrics and Gerontology, Obu City, Aichi, Japan. [email protected]
OBJECTIVES:
To determine the approximate percentage of women in nursing homes who have vitamin D deficiency and to investigate whether, in assessing vitamin D status in elderly women, there are problems with measuring only 25 hydroxy-vitamin D(3) (25(OH)D(3) ) and whether decreased vitamin D activation as a result of poor renal function needs to be considered.
DESIGN:
Cross-sectional study.
SETTING:
Forty-eight nursing homes in Japan.
PARTICIPANTS:
Four hundred three women with a mean age of 86.5 living in nursing homes who had participated in a clinical trial for hip protectors and were not bedridden.
MEASUREMENTS:
At the start of the trial, in addition to general biochemical data, 25(OH)D(3) , 1,25-dihydroxy-vitamin D(3) (1,25(OH)(2) D(3) ), intact parathyroid hormone (intact PTH), calcium (Ca), phosphorus (P), bone alkaline phosphate (BAP), cross-linked N-telopeptide of type I collagen (NTx), and osteocalcin were measured in participants' blood, and statistical analysis was performed.
RESULTS:
25(OH)D(3) , which is thought to reflect vitamin D status in the body, was surveyed and found to have a mean value of 16.7 ng/mL. 25(OH)D(3) was less than 16 ng/mL in 49.1% of all participants.
Creatinine clearance (CCr) was less than 30 mL/min in 20.1% of participants.
Participants with serum 25(OH)D(3) less than 16 ng/mL and CCr less than 30 mL/min had significantly higher levels of intact PTH and serum Ntx.
Participants with a CCr less than 30 mL/min had significantly lower levels of 1,25(OH)(2) D(3) .
CONCLUSION:
Frail elderly adults living in nursing homes with poor renal function had lower 1,25(OH)(2) D(3) and higher intact PTH levels and were thus thought to have poorer vitamin D activating capacity. Supplementation with cholecalciferol may be insufficient in people who have poor renal function.
© 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.
PMID: 22283781
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This appears to show association only:
Could be poor kidney ==> low vitamin D production
Could be low level of vitamin D ==> poor kidney