Intake of Trace Metals and the Risk of Incident Kidney Stones

J Urol. 2018 Jun;199(6):1534-1539. doi: 10.1016/j.juro.2018.01.077. Epub 2018 Jan 31.

Abstract

Purpose: The association between the intake of trace metals and the risk of incident stones has not been longitudinally investigated.

Materials and methods: We performed a prospective analysis of 193,551 participants in the Health Professionals Follow-up Study, and the Nurses' Health Study I and II. During a followup of 3,316,580 person-years there was a total of 6,576 incident stones. We used multivariate regression models to identify associations of the intake of zinc, iron, copper and manganese with the risk of stones. In a subset of participants with 24-hour urine collections we examined the association between the intake of trace metals and urine composition.

Results: After multivariate adjustment total and dietary intakes of zinc and iron were not significantly associated with incident stones. A higher intake of manganese was associated with a lower risk of stones. The pooled HR of the highest quintile of total manganese intake compared with the lowest intake was 0.82 (95% CI 0.68-0.98, p = 0.02). Total but not dietary copper intake was marginally associated with a higher risk of stones (pooled HR 1.14, 95% CI 1.02-1.28, p = 0.01). There were no statistically significant associations of the total intake of manganese and copper with urinary supersaturation.

Conclusions: Zinc and iron intake was not associated with a risk of stones. Copper intake may be associated with a higher risk in some individuals. Higher total manganese intake was associated with a lower risk of stones but not with traditional 24-hour urinary composite markers of stone risk. Further research is needed to elucidate the mechanisms by which manganese may reduce kidney stone formation.

Keywords: iron; kidney calculi; manganese; nutritional status; zinc.

MeSH terms

  • Adult
  • Aged
  • Feeding Behavior*
  • Female
  • Follow-Up Studies
  • Health Personnel / statistics & numerical data
  • Humans
  • Incidence
  • Kidney Calculi / epidemiology*
  • Kidney Calculi / etiology
  • Kidney Calculi / urine
  • Male
  • Middle Aged
  • Prospective Studies
  • Risk Assessment
  • Risk Factors
  • Trace Elements / administration & dosage
  • Trace Elements / adverse effects*
  • Urine / chemistry

Substances

  • Trace Elements