Lower kidney function is independently associated with an increased risk of cardiovascular disease (CVD) and death in stable kidney transplant recipients, according to investigators.
At an estimated glomerular filtration rate (eGFR) below 45 mL/min/1.73 m2, each 5 mL/min/1.73 m2 increment in eGFR is associated with a 15% decreased risk of both CVD and death, researchers reported online in the American Journal of Transplantation. The investigators, led by Daniel E. Weiner, MD, of Tufts Medical Center in Boston, observed no association between eGFR and outcomes at eGFR levels above 45.
“The presence of an association between low eGFR and cardiovascular disease in transplant recipients suggests that comorbid conditions associated with low GFR itself rather than concurrent comorbidities that result in both low eGFR as well as systemic cardiovascular disease may be impacting cardiovascular risk,” the investigators wrote.
Reduced eGFR is independently associated with CVD events and mortality in the general population, the researchers noted. “Finding a similar relationship in kidney transplant recipients as in the general population suggests a possible direct effect of reduced GFR, since the transplanted kidney is likely to not have had a long exposure to traditional and nontraditional CVD risk factors,” the authors stated.
Dr. Weiner and his colleagues conducted a post-hoc analysis of data from 4,016 participants in the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) trial—which included patients who received a kidney transplant at least six months before enrollment. Over a median of 3.8 years, 527 CVD events occurred in the 3,676 subjects who had complete data.
They pointed out that their study has multiple strengths, including a large cohort, extensive ascertainment of CVD risk factors, systematic prospective ascertainment of CVD events, and the measurement of serum creatinine by a single laboratory. The study also has some weaknesses, including a lack of data on albuminuria and only a single assessment of serum creatinine for eGFR determination.