PMID- 32886188
OWN - NLM
STAT- MEDLINE
DCOM- 20210318
LR  - 20220302
IS  - 1433-2965 (Electronic)
IS  - 0937-941X (Print)
IS  - 0937-941X (Linking)
VI  - 32
IP  - 3
DP  - 2021 Mar
TI  - Reference range for 24-h urine calcium, calcium/creatinine ratio, and 
      correlations with calcium absorption and serum vitamin D metabolites in normal 
      women.
PG  - 539-547
LID - 10.1007/s00198-020-05615-6 [doi]
AB  - A study of 959 black and white women shows that the normal range for 24-h urine 
      calcium excretion in white women is 30-300 mg and 10-285 mg in black women. 
      Clinical laboratories use a normal range for 24-h urine calcium excretion of 
      100-300 mg; there is a need for them to update their age- and race-specific 
      ranges. INTRODUCTION: Recommendations for a normal range for 24-h urine calcium 
      vary from a low of 50 mg to a high of 400 mg; most "laboratory normal ranges" 
      based on older literature are incorrect. The objective of this analysis is to 
      define a normal range for young women age 25-45 years and older women age 55-90 
      years, white and black, for 24-h urine calcium and calcium/creatinine ratio, and 
      to examine the relationship between 24-h urine calcium, calcium absorption, and 
      vitamin D metabolites. METHODS: Data from 3 studies was collected on 959 normal 
      black and white women, ages 25-87 years, for 24-h urine calcium, creatinine, 
      calcium intake, serum 25-hydroxyvitamin D (25OHD),1,25 dihydroxyvitamin D 
      (1,25(OH)(2)D), and calcium absorption. Urine calcium and creatinine were 
      measured on an auto-analyzer. Calcium absorption was measured by a single isotope 
      method. Serum 25OHD and 1,25(OH)(2)D were measured by competitive protein binding 
      assay or radioimmunoassay. Because 24-h urine calcium did not fit a normal 
      distribution, non-parametric methods were used to determine the 95% reference 
      interval (RI) and 90% non-parametric confidence intervals (CI) calculated for 
      groups. RESULTS: The 95% reference intervals for 24-h urine calcium for women 
      were as follows: black older 7-225 mg, black younger 8-285 mg; white older 37-275 
      mg, and white younger 23-287 mg. In older white women, 24-h urine calcium was 
      significantly correlated with serum 1,25(OH)(2) D, r = 0.23, p < 0.001, calcium 
      intake r = 0.12, p = 0.001, and calcium absorption r = 0.18, p = 0.003, but not 
      serum 25OHD r = 0.07, p = 0.06. CONCLUSIONS: The normal reference interval for 
      24-h urine calcium for black women is lower than white women. Twenty-four-hour 
      urine calcium was correlated with serum 1,25(OH)(2) D calcium intake and calcium 
      absorption, but not serum 25OHD. This range will be useful clinically for 
      defining hypercalciuria and for following patients on vitamin D and calcium 
      treatment.
FAU - Smith, L M
AU  - Smith LM
AUID- ORCID: 0000-0002-0836-9932
AD  - Department of Biostatistics, University of Nebraska Medical Center, Omaha, NE, 
      USA. lmsmith@unmc.edu.
FAU - Gallagher, J C
AU  - Gallagher JC
AD  - Bone Metabolism Unit, Creighton University School of Medicine, Omaha, NE, USA.
LA  - eng
GR  - UO1-AG10373/AG/NIA NIH HHS/United States
GR  - AG28168/AG/NIA NIH HHS/United States
GR  - R01 AG028168/AG/NIA NIH HHS/United States
GR  - RO1-AG10358/AG/NIA NIH HHS/United States
GR  - W81XWH-07-1-201/U.S. Department of Defense/
PT  - Journal Article
DEP - 20200904
PL  - England
TA  - Osteoporos Int
JT  - Osteoporosis international : a journal established as result of cooperation 
      between the European Foundation for Osteoporosis and the National Osteoporosis 
      Foundation of the USA
JID - 9100105
RN  - 0 (Calcium, Dietary)
RN  - 0 (Parathyroid Hormone)
RN  - 1406-16-2 (Vitamin D)
RN  - AYI8EX34EU (Creatinine)
RN  - SY7Q814VUP (Calcium)
SB  - IM
CIN - J Urol. 2021 Mar;205(3):924-925. PMID: 33356459
MH  - Adult
MH  - Aged
MH  - Aged, 80 and over
MH  - *Calcium
MH  - *Calcium, Dietary
MH  - Creatinine
MH  - Female
MH  - Humans
MH  - Middle Aged
MH  - Parathyroid Hormone
MH  - Reference Values
MH  - Vitamin D
PMC - PMC8451703
MID - NIHMS1626558
OTO - NOTNLM
OT  - 24-h urine calcium
OT  - Black and white women
OT  - Calcium/creatinine ratio
OT  - Reference interval
COIS- Conflicts of interest/Competing interests: none
EDAT- 2020/09/05 06:00
MHDA- 2021/03/19 06:00
PMCR- 2022/03/01
CRDT- 2020/09/05 06:00
PHST- 2020/05/06 00:00 [received]
PHST- 2020/08/25 00:00 [accepted]
PHST- 2020/09/05 06:00 [pubmed]
PHST- 2021/03/19 06:00 [medline]
PHST- 2020/09/05 06:00 [entrez]
PHST- 2022/03/01 00:00 [pmc-release]
AID - 10.1007/s00198-020-05615-6 [pii]
AID - 10.1007/s00198-020-05615-6 [doi]
PST - ppublish
SO  - Osteoporos Int. 2021 Mar;32(3):539-547. doi: 10.1007/s00198-020-05615-6. Epub 
      2020 Sep 4.