Coronary artery calcification and chronically decreased GFR in living kidney donors

In the presence of decreased glomerular filtration rate (GFR), the risk of morbidity and mortality caused by cardiovascular disease (CVD) is increased markedly. Increased coronary artery calcification (CAC) is proposed as a pathogenetic link between CVD and chronic kidney disease. We examined the frequency and severity of CAC in living kidney donors to test the hypothesis that decreased GFR is associated with increased CAC.

We used multidetector spiral computed tomography to examine CAC in 101 living kidney donors and 99 age- and sex-matched healthy control subjects without diabetes and a history of coronary artery disease. The extent of calcification was measured by means of the Agatston score. GFR was calculated by using the abbreviated Modification of Diet in Renal Disease formula. The frequency of risk factors for coronary artery disease was compared in kidney donors and controls, and the relation between kidney donors' clinical characteristics and the presence or absence of CAC was examined.

CAC frequency and mean calcification scores were similar between kidney donors (13.9%; 4.5 +/- 22.6) and controls (17.2%; 13.2 +/- 89.2). CAC was not associated with decreased GFR, and the correlation between CAC and GFR was not statistically significant. Kidney donors with calcification were more likely to be older (P = 0.003) and male (P = 0.001). Age- and sex-adjusted analysis showed an association between greater parathormone levels (odds ratio, 1.023; 95% confidence interval, 1.001 to 1.045; P = 0.037) and CAC in kidney donors.

A mild decrease in GFR without the presence of diabetes does not seem to be associated with increased CAC. These findings need to be confirmed in different and larger study populations.