ABSTRACT
Baseline reduced kidney function is highly prevalent among patients with acute heart failure (AHF) and is one
of the most powerful risk factors for adverse clinical outcomes. The association between acute kidney function
declines and outcomes, however, remain controversial, with some studies showing acute declines in estimated
glomerular filtration (eGFR) to be associated with worse outcomes but other studies not. The goal of Dr.
McCallum’s proposal is to better understand the mechanisms of acute eGFR declines that occur in the setting
of AHF and examine how acute eGFR declines are related to outcomes including long term kidney function,
mortality and AHF hospitalizations. The overall hypothesis is that three key components—congestion,
cardiac hemodynamics, and neurohormonal (NH) activity—are the primary risk factors for acute eGFR
declines, and that the relation between acute eGFR declines and clinical outcomes needs to be interpreted
within the context of changes in these three factors. In order to examine these relations, her Aims would
include 1) retrospective analysis of patients admitted to Tufts Medical Center for AHF and requiring a
pulmonary artery (PA) catheter (n=890) for repeated measures of congestion and cardiac hemodynamics; 2)
prospective enrollment of 140 patients admitted to Tufts Medical Center for AHF with an indwelling PA catheter
to assay for repeated measures of plasma NH activity; and 3) adoption of multi-trajectory modeling to develop
clinical phenotypes of acute cardiorenal syndrome (CRS) by incorporating trajectories of eGFR change,
congestion, cardiac hemodynamics, and NH activity. The career development plan incorporates didactic
training in longitudinal data analysis including joint modeling and multi-trajectory modeling, biomarker
methodology, introductory informatics for electronic health record research, as well as immersion and practical
training in cardiac hemodynamics and prospective patient recruitment, all under the mentorship of an
experienced group of nephrologists, cardiologists and statisticians with expertise in various aspects of the
CRS. Successful completion of these aims is feasible, as shown by Dr. McCallum’s preliminary data under her
institutional KL2 funding, as well her track record of productivity under her primary mentor Dr. Mark Sarnak.
Her co-mentor will be Dr. Jeffrey Testani, a cardiologist and Director of Heart Failure Research at Yale
University who has expertise in the CRS, has collaborated with Dr. McCallum on several manuscripts, and has
incorporated her into his research group and sponsored several trips for her to his research lab at Yale. With
this K23 award, Dr. McCallum will receive extensive training in biostatistical methods, dataset creation, CRS
pathophysiology, biomarker methodology, primary data collection and prospective study design. In aggregate,
completion of these aims will provide Dr. McCallum with expertise in the CRS and arm her with the tools
necessary to successfully compete for independent funding.