Baroreceptor Sensitivity in Individuals with CKD and Heart Failure

Key Points We found that cardiac baroreceptor sensitivity (BRS), which reflects the integrity of autonomic responses to changes in BP, was depressed in individuals with both CKD and heart failure compared with those with heart failure and preserved kidney function. Depressed BRS was associated with the risk of cardiovascular death, whereas CKD in the absence of depressed BRS was not associated with the risk of cardiovascular death. Our findings suggest that depressed BRS may be a critical contributor to the increased risk of cardiovascular death in individuals with CKD and heart failure. Background Heart failure is the most common cardiovascular complication of chronic kidney disease (CKD) and foreshadows a high morbidity and mortality rate. Baroreflex impairment likely contributes to cardiovascular mortality. We aimed to study the associations between CKD, heart failure, and baroreflex sensitivity (BRS) and their association with cardiovascular outcomes. Methods We retrospectively analyzed data from a cohort of 247 individuals with moderate to severe HF. All subjects underwent BRS measurements after intravenous phenylephrine along with electrocardiography, echocardiography, and laboratory measurements. We used logistic regression models to assess the association of CKD (estimated glomerular filtration rate <60 ml/min per 1.73 m 2 ) with BRS using iterative models. Cox proportional hazards models were used to assess associations of binary BRS and subgroups according to categorizations of CKD and BRS with cardiovascular mortality. Results Median eGFR among individuals with CKD was 52 (IQR 44–56) ml/min per 1.73 m 2 . eGFR was lower in those with depressed BRS (65 [IQR 54–76] ml/min per 1.73 m 2 ) compared with those with preserved BRS (73 [IQR 64–87] ml/min per 1.73 m 2 ; P ≤0.001). The majority of individuals with CKD had depressed BRS compared with those without CKD (60% versus 29%; P =0.05). In regression models, CKD and BRS were independently associated. Cardiovascular mortality was significantly increased in individuals with or without CKD and depressed BRS compared with those with preserved BRS and CKD. Conclusions Cardiac BRS is depressed in patients with mild to moderate CKD and HF and associated with cardiovascular mortality. Additional study to confirm its contribution to cardiovascular mortality, particularly in advanced CKD, is warranted.