Kidney cadmium levels and associations with urinary calcium and bone mineral density: a cross-sectional study in Sweden

Environmental Health

Research

Elisabeth Fabricius-Lagging¹  Thomas Lundh²  Gerd Sallsten³  Lars Barregard³  Maria Wallin³  Christian Öhrn³ 

[1] Department of Nephrology, Sahlgrenska University Hospital, Gothenburg, Sweden;Department of Nephrology, Boras Hospital, Boras, Sweden;Department of Occupational and Environmental Medicine, Lund University Hospital, Lund, Sweden;Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and Academy, University of Gothenburg, PO Box 414, SE-405 30, Gothenburg, Sweden;

关键词: Bone;    Bone mineral density;    Cadmium;    Kidney;    Urinary calcium;    Kidney donor;   

DOI  :  10.1186/1476-069X-12-22

 received in 2012-11-14, accepted in 2013-02-28,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundCadmium (Cd) can cause renal damage and osteoporosis after high-level exposure. Recently such effects, including increased urinary excretion of calcium, have been shown also at low-level exposure, as measured by Cd in blood or urine. However, associations with kidney Cd have not been examined. The aim of this study was to explore the relation between kidney Cd and urinary calcium excretion, or bone mineral density.MethodsCd was determined in kidney cortex biopsies from 109 living kidney donors. Serum was analyzed for ionized calcium, parathyroid hormone and vitamin D. Calcium was analyzed in overnight and 24-hour urine samples. Bone mineral density was measured in a subgroup of 67 donors. Associations between single variables were assessed by Spearman and Pearson correlation coefficients. Differences between independent groups were compared using Student’s t-test. For related samples, paired t-test was applied. Associations between urinary calcium and kidney Cd, ionized serum calcium, serum parathyroid hormone, inactive and active vitamin D and background variables were assessed using multiple linear regression and logistic regression.ResultsIn spite of relatively low kidney Cd levels (median 13 μg/g, range 1.5-55 μg/g) kidney Cd and urinary calcium were positively associated, mainly caused by an association in women. Donors with kidney Cd above the median (subgroup mean 23 μg/g) had significantly higher excretion of urinary calcium normalized for creatinine than those below the median (subgroup mean 7.3 μg/g). In women, also the excretion of Ca per hour was higher in those with high kidney Cd (24 hour sample mean 0.21 vs. 0.15 mmol/h; overnight sample 0.16 vs. 0.11 mmol/h). There were negative associations between kidney Cd and bone mineral density, most of which, however, disappeared in multivariate analyses.ConclusionsThis study provides support for an association between kidney Cd levels and urinary calcium excretion in women, but not in men. The results strengthen the case for preventive measures against Cd pollution.

【 授权许可】

CC BY   
© Wallin et al.; licensee BioMed Central Ltd. 2013