A KRISHNAN1, J LEWIS2, G WONG4,5,6,7, R PRINCE1,3, W LIM1,7
1Sir Charles Gairdner Hospital, Perth, Australia, 2Edith Cowan University, Perth, Australia, 3University of Western Australia, Perth, Australia, 4Centre for Renal and Transplant Research, Westmead Hospital, Sydney, Australia, 5Centre for Kidney Research at the Children’s Hospital at Westmead, Sydney, Australia, 6Sydney School of Public Health, University of Sydney, Sydney, Australia, 7Australia and New Zealand Dialysis and Transplant Registry, , Australia
Aim: To examine the associations between BNP, long-term change in kidney function and 10-year risk of CKD-related events (hospitalisations and/or mortality) in older Caucasian women.
Background: BNP is a cardiac biomarker which has been shown to be predictive for cardiovascular and all-cause mortality in the general population and in patients with CKD. One recent study suggests that BNP may predict kidney function decline, possibly related to effect of abnormal cardiac remodelling/pressure on kidney perfusion. However, the association between BNP, kidney function decline and development of CKD-related events remains unknown.
Methods: This is a population cohort study of 840 women aged ≥70 years. The associations between log-transformed BNP (logBNP), 10-year change in estimated glomerular filtration rate (eGFR, with repeated measures at baseline, 5 and 10-years) and 10-year risk of CKD-related events were assessed using linear mixed model and Cox regression analysis, respectively.
Results: Over a follow-up period of 10 years, there were 79 CKD-related events. The mean decline of eGFR over 10-years was -0.26ml/min/1.73m2/year (95%CI -0.36, -0.15; p<0.001) for every SD increase in logBNP, adjusted for age, comorbid conditions and prevalent atherosclerotic vascular disease. In the multivariate model for CKD-related events, the adjusted hazard ratio (HR) for every SD increase in logBNP was 1.51 (95%CI 1.17, 1.95; p<0.001), adjusted for Framingham risk scores, age and baseline eGFR. In the sensitivity analyses excluding women with prevalent atherosclerotic-vascular or kidney disease (n=116), the estimates between BNP and CKD-related events remained unchanged.
Conclusion: Elevated levels of BNP were associated with a more rapid decline in eGFR and increased risk of long-term CKD-related events in older women, independent of traditional vascular risk factors and baseline kidney function.
Anoushka completed her advanced training in nephrology this year, having done two years in Perth followed by a year in Vancouver, Canada. She has a keen interest in transplantation and CKD.