Gregory E Tasian1, Michelle E Ross2, Lihai Song3, Robert W Grundmeier4, James Massey5, Michelle R Denburg6, Lawrence Copelovitch7, Steven Warner8, Thomas Chi9, David W Killilea10, Marshall L Stoller9, Susan L Furth6. 1. Division of Pediatric Urology, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Division of Urology, Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: tasiang@chop.edu. 2. Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania. 3. Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. 4. Division of General Pediatrics, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania. 5. Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. 6. Division of Nephrology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania. 7. Division of Nephrology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania. 8. Division of Pediatric Urology, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. 9. Department of Urology, University of California, San Francisco, San Francisco. 10. Center for Nutrition and Metabolism, Children's Hospital Oakland Research Institute, Oakland, California.
Abstract
PURPOSE: We determined the association between dietary zinc intake and incident calcium kidney stones in adolescents. We also examined the relationship between dietary zinc intake and urinary zinc excretion between cases and controls. MATERIALS AND METHODS: We conducted a nested case-control study within a large pediatric health care system. Three 24-hour dietary recalls and spot urine chemistry analyses were obtained for 30 participants 12 to 18 years old with a first idiopathic calcium based kidney stone and 30 healthy controls matched for age, sex, race and month of enrollment. Conditional logistic regression models were used to estimate the association between daily zinc intake and incident calcium kidney stones, adjusting for dietary phytate, protein, calcium, sodium and oxalate. Multivariable linear regression was used to estimate the association between dietary and urine zinc, adjusting for urine creatinine and dietary phytate and calcium. RESULTS: Cases had lower daily zinc intake (8.1 mg) than controls (10 mg, p = 0.029). Daily zinc intake of boys and girls with calcium stones was 2 mg and 1.2 mg less, respectively, than the daily intake recommended by the Institute of Medicine. Odds of incident stones were reduced by 13% for every 1 mg increase in daily zinc intake (OR 0.87, 95% CI 0.75-0.99). There was an estimated 4.5 μg/dl increase in urine zinc for every 1 mg increase in dietary zinc (p = 0.009), with weak evidence of a smaller increase in urine zinc in cases than in controls (interaction p = 0.08). CONCLUSIONS: Decreased dietary zinc intake was independently associated with incident calcium nephrolithiasis in this population of adolescents.
PURPOSE: We determined the association between dietary zinc intake and incident calciumkidney stones in adolescents. We also examined the relationship between dietary zinc intake and urinary zinc excretion between cases and controls. MATERIALS AND METHODS: We conducted a nested case-control study within a large pediatric health care system. Three 24-hour dietary recalls and spot urine chemistry analyses were obtained for 30 participants 12 to 18 years old with a first idiopathic calcium based kidney stone and 30 healthy controls matched for age, sex, race and month of enrollment. Conditional logistic regression models were used to estimate the association between daily zinc intake and incident calciumkidney stones, adjusting for dietary phytate, protein, calcium, sodium and oxalate. Multivariable linear regression was used to estimate the association between dietary and urine zinc, adjusting for urine creatinine and dietary phytate and calcium. RESULTS: Cases had lower daily zinc intake (8.1 mg) than controls (10 mg, p = 0.029). Daily zinc intake of boys and girls with calcium stones was 2 mg and 1.2 mg less, respectively, than the daily intake recommended by the Institute of Medicine. Odds of incident stones were reduced by 13% for every 1 mg increase in daily zinc intake (OR 0.87, 95% CI 0.75-0.99). There was an estimated 4.5 μg/dl increase in urine zinc for every 1 mg increase in dietary zinc (p = 0.009), with weak evidence of a smaller increase in urine zinc in cases than in controls (interaction p = 0.08). CONCLUSIONS: Decreased dietary zinc intake was independently associated with incident calciumnephrolithiasis in this population of adolescents.
Authors: Andrew P Evan; James E Lingeman; Fredric L Coe; Joan H Parks; Sharon B Bledsoe; Youzhi Shao; Andre J Sommer; Ryan F Paterson; Ramsay L Kuo; Marc Grynpas Journal: J Clin Invest Date: 2003-03 Impact factor: 14.808