In the VA population, the prevalence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2, increases from <5% among adults 18-44 years old to nearly 50% among those >85 years old. CKD is associated with many adverse outcomes including the development of end-stage renal disease (ESRD) as well as higher rates of mortality, cardiovascular disease (CVD), CKD- related complications and functional decline. While the presence of abnormalities in kidney function in older Veterans with CKD are clearly associated with adverse health outcomes, many of these patients have multiple co-morbid conditions and diminished functional reserve across a range of organ systems. The prevalence of hypertension, diabetes, and CVD and the burden of frailty and disability are substantial in older adults with CKD. In the geriatric population, the presence of these other conditions may diminish the value of a purely disease-oriented approach that focuses only on the role of intrinsic kidney abnormalities in understanding trajectories of kidney function. In contrast, an individualized, patient-centered approach prioritizes patient goals and preferences and recognizes that observed signs and symptoms in older adults are often multi-factorial reflecting the complex interplay between one or more chronic predisposing and acute precipitating events. With this in mind, we propose an incremental research agenda to better understand the predictors, outcomes and significance of different longitudinal trajectories of kidney function in older Veterans. Only a few prior studies have evaluated longitudinal trajectories of kidney function. These studies demonstrate that there is substantial heterogeneity in kidney function trajectories in patients with CKD and that many patients follow a non-linear disease trajectory. Furthermore, qualitative work has suggested that uncertainty about the expected course of CKD appears to be an important concern among both patients and providers.
In Aim 1, we will identify long- term predisposing factors and short-term precipitating factors associated with a decline in eGFR trajectory among older Veterans with CKD using multilevel change regression models. In addition to traditional measures of kidney disease burden, we will evaluate a range of time-varying factors of special relevance to older adults such as use and dosing of medications and intercurrent health events such as acute illness and hospitalization.
In Aim 2, we will evaluate the association of different eGFR trajectories with both traditional CKD outcomes and nontraditional, patient-centered outcomes of relevance to older adults with CKD (e.g., nursing home admission). Finally, in Aim 3, we will examine how older Veterans view and prioritize challenges related to CKD self-management at specific points along different eGFR trajectories using the nominal group technique (NGT). Knowledge of these barriers will allow us to better engage patients in shared-decision making and problem solving strategies as well as design patient- and family-centered interventions directly targeting these barriers. Older adults are particularly vulnerable to changes in health status or acute insults. However, prior studies have not addressed how dynamic changes in the health of older CKD patients impact eGFR trajectory. Further we do not know the significance of eGFR trajectory from the patient's perspective. To fill these knowledge gaps we propose a comprehensive approach using both advanced statistical methods and an innovative qualitative component that will identify (1) time-varying and event-based factors associated with a decline in eGFR trajectory, (2) patient-centered outcomes associated with eGFR trajectory, and (3) patient-reported barriers to CKD self-management at specific points in eGFR trajectory.
Chronic kidney disease (CKD) is more common as people age and is associated with end-stage renal disease (ESRD), death, heart disease, and loss of functional abilities. While kidney function can worsen over time, few studies have evaluated the trajectory or pattern of change in kidney function over time. In the proposed study, we will use VA data from older adults with multiple measures of kidney function over as many as six years to provide a detailed characterization of factors that shape disease trajectories in older adults. We will also determine the association of disease trajectories with poor outcomes that are highly important to older adults such as nursing home admission. Finally, we will ask older Veterans with CKD to report and rank the barriers that limit their ability to follow recommended CKD treatments. This study will identify older Veterans at high risk for declining CKD and lead to future studies targeting older adults who are most likely to benefit from treatments to prevent CKD-related health problems.