Serum levels of the anti-anabolic bone protein sclerostin are associated with an increased risk of cardiovascular events and mortality in patients with chronic kidney disease (CKD), according to a new study.

Alterations in mineral homeostasis that accompany worsening of kidney function—leading to CKD–mineral and bone disorder syndrome—are an important contributor to CKD-associated cardiovascular disease and mortality. As serum levels of sclerostin have previously been shown to positively correlate with the progression of CKD, the researchers investigated the potential of using sclerostin levels to predict future cardiovascular events and mortality in a population with CKD not undergoing dialysis.

Serum sclerostin levels were significantly higher in 173 patients with CKD (stages 3–5) than in 47 control individuals (without CKD, diabetes or hypertension) and increased with the severity of CKD. When patients with CKD were stratified according to the median sclerostin level (63.5 pmol/l), the group who had levels above the median had worse outcomes (14 deaths, 43 cardiovascular events) than the group with levels below the median (5 deaths, 7 cardiovascular events). Although sclerostin levels above 63.5 pmol/l were only significantly associated with cardiovascular events in multivariate analysis, sclerostin levels above a higher cut-off of 69.0 pmol/l were associated with all-cause mortality.

The results add to previous findings suggesting an important role for sclerostin in the bone–vascular axis; the exact nature of that role, however, remains to be clarified.