Vascular calcification in patients with preserved renal function

Abstract

To the Editor: Vascular calcification was the subject of a recent review article1.Goldsmith D. Ritz E. Covic A. Vascular calcification: A stiff challenge for the nephrologist.Kidney Int. 2004; 66: 1315-1333Abstract Full Text Full Text PDF PubMed Scopus (139) Google Scholar, the subtitle of which was: Does preventing bone disease cause arterial disease? The authors discuss the possible link between calcium intake and cardiovascular disease. This link may be particularly important in patients with renal failure, but mention was made to the fact that a similar relation may exist in patients not on dialysis2.Seely S. Possible connection between milk and coronary heart disease: The calcium hypothesis.Med Hypotheses. 2000; 54: 701-703Abstract Full Text PDF PubMed Scopus (14) Google Scholar. We have studied plasma calcium and phosphorus in 110 patients with coronary atherosclerosis and relatively preserved renal function (plasma creatinine smaller than 2 mg/dL) that underwent coronary angiography after an acute coronary syndrome3.Nunes J.P.L. Faria M.S. Maciel M.J. Garcia J.M.M. Correlation between plasma calcium and coronary artery disease burden in patients with preserved renal function.Int J Cardiol. July 2004Google Scholar. Coronary artery disease burden was significant correlated with plasma calcium, but not with plasma phosphorus. A possible cut-off level for plasma calcium at 2.20 mmol/L was established3.Nunes J.P.L. Faria M.S. Maciel M.J. Garcia J.M.M. Correlation between plasma calcium and coronary artery disease burden in patients with preserved renal function.Int J Cardiol. July 2004Google Scholar. These results are at odds with a previous report that showed that plasma phosphorus, but not plasma calcium, had an independent positive association with the angiographic severity of coronary disease, in a cohort of 376 stable patients without known renal disease4.Narang R. Ridout D. Nonis C. Kooner J.S. Serum calcium, phosphorus and albumin levels in relation to the angiographic severity of coronary artery disease.Int J Cardiol. 1997; 60: 73-79Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar. It is unclear if subclinical renal failure (a condition in which phosphorus and calcium metabolism is changed) may have existed in this latter cohort. Plasma calcium3.Nunes J.P.L. Faria M.S. Maciel M.J. Garcia J.M.M. Correlation between plasma calcium and coronary artery disease burden in patients with preserved renal function.Int J Cardiol. July 2004Google Scholar or plasma phosphorus4.Narang R. Ridout D. Nonis C. Kooner J.S. Serum calcium, phosphorus and albumin levels in relation to the angiographic severity of coronary artery disease.Int J Cardiol. 1997; 60: 73-79Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar may be correlated with the severity of coronary atherosclerotic disease in patients with relatively preserved renal function3.Nunes J.P.L. Faria M.S. Maciel M.J. Garcia J.M.M. Correlation between plasma calcium and coronary artery disease burden in patients with preserved renal function.Int J Cardiol. July 2004Google Scholar, or in patients without known renal disease4.Narang R. Ridout D. Nonis C. Kooner J.S. Serum calcium, phosphorus and albumin levels in relation to the angiographic severity of coronary artery disease.Int J Cardiol. 1997; 60: 73-79Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar. This may indicate a need for a reassessment of calcium supplementation, not only in dialysis patients, but also in patients with preserved renal function.