Faculty Bibliography

RATIONALE & OBJECTIVE/OBJECTIVE:Despite substantial growth in the population of older adults with kidney disease, there remains a lack of evidence to guide clinical care for this group. The Kidney Disease and Aging Research Collaborative (KDARC) conducted a Delphi study to build consensus on research priorities for clinical geriatric nephrology. STUDY DESIGN/METHODS:Asynchronous modified Delphi study. SETTING & PARTICIPANTS/METHODS:Clinicians and researchers in the US and Canada with clinical experience and/or research expertise in geriatric nephrology. OUTCOME/RESULTS:Research priorities in geriatric nephrology. ANALYTICAL APPROACH/METHODS:In the first Delphi round, participants submitted free-text descriptions of research priorities considered important for improving the clinical care of older adults with kidney disease. Delphi moderators used inductive content analysis to group concepts into categories. In the second and third rounds, participants iteratively reviewed topics, selected their top 5 priorities, and offered comments used to revise categories. RESULTS:Among 121 who were invited, 57 participants (47%) completed the first Delphi round and 48 (84% of enrolled participants) completed all rounds. After 3 rounds, the 5 priorities with the highest proportion of agreement were: 1) Communication and Decision-Making about Treatment Options for Older Adults with Kidney Failure (69% agreement), 2) Quality of Life, Symptom Management, and Palliative Care (67%), 3) Frailty and Physical Function (54%), 4) Tailoring Therapies for Kidney Disease to Specific Needs of Older Adults (42%), and 5) Caregiver and Social Support (35%). Health equity and person-centricity were identified as cross-cutting features that informed all topics. LIMITATIONS/CONCLUSIONS:Relatively low response rate and limited participation by private practitioners and older clinicians and researchers. CONCLUSIONS:Experts in geriatric nephrology identified clinical research priorities with the greatest potential to improve care for older adults with kidney disease. These findings provide a roadmap for the geriatric nephrology community to harmonize and maximize the impact of research efforts.

PURPOSE OF REVIEW/OBJECTIVE:Despite emerging studies on neighborhood-level risk factors for chronic kidney disease (CKD), our understanding of the causal links between neighborhood characteristics and CKD is limited. In particular, there is a gap in identifying modifiable neighborhood factors, such as the built environment, in preventing CKD, that could be targets for feasible place-based interventions. RECENT FINDINGS/RESULTS:Most published studies on neighborhood factors and CKD have focused on a single social attribute, such as neighborhood disadvantage, while research on the role of the built environment is more nascent. Early studies on this topic have yielded inconsistent results, particularly regarding whether food deserts are an environmental risk factor for CKD onset. International studies have shown that walkable neighborhoods - characterized by features such as urban design, park access, and green spaces - can be protective against both the onset and progression of CKD. However, these findings are inconclusive and understudied in the context of United States, where neighborhood environments differ from those in other countries. SUMMARY/CONCLUSIONS:Future research on modifiable neighborhood factors and CKD using advanced study designs and population-representative datasets can yield stronger evidence on potential causal associations and suggest feasible place-based interventions as strategies for preventing CKD. As an example, we demonstrated the potential of electronic health record-based studies to advance research in this area.

BACKGROUND AND HYPOTHESIS/OBJECTIVE:Hepatitis C virus (HCV) positive-to-negative kidney transplants (KT) require direct acting antiviral therapy, but the optimal timing and duration remain unclear. We hypothesized that 14-day prophylactic course of glecaprevir/pibrentasvir 300/120 mg (GLE/PIB) would be safe and effective at treating donor-derived HCV viremia. METHODS:This was a prospective, single-center, single-arm, open-label pilot study. 20 adult HCV negative recipients of HCV nucleic acid amplification test positive deceased-donor kidneys (HCV positive-to-negative) received a 14-day course of GLE/PIB, with the first dose pre-transplant. HCV RNA viral loads (VL) were monitored on post-operative days (POD) 1, 3, 7, and 13. If VL was undetectable on POD 13, GLE/PIB was stopped, and if detectable, GLE/PIB was continued to complete an 8-week course. Surveillance monitoring continued after treatment to ensure sustained viral response (SVR). The primary outcome was efficacy of 14-day prophylactic GLE/PIB. Secondary outcomes included patient and allograft survival, the incidence, timing, and clearance of HCV viremia, and safety events. RESULTS:7/20 subjects (35%) never developed detectable HCV viremia. Only one subject had a detectable, but nonquantifiable, VL on POD 13 and completed an 8-week course. All subjects achieved SVR 12 weeks post-treatment with no relapses through 1-year follow-up. Mean time to undetectable HCV RNA VL was 10.5 (±4.7) days and mean peak VL was 371 (±715) copies/mL. 6-month and 1-year patient and allograft survival were 100% and 95%. CONCLUSION/CONCLUSIONS:A 14-day course of prophylactic GLE/PIB is safe and effective for HCV positive-to-negative KT and may prevent HCV transmission or significantly reduce the VL for those with detectable transmission allowing for rapid clearance within 2 weeks.

AIMS/HYPOTHESIS/OBJECTIVE:39-47 mmol/mol [5.7-6.4%] or fasting glucose 5.6-6.9 mmol/l) is associated with elevated risks of microvascular and macrovascular complications. It is unknown to what extent these risks in prediabetes remain after accounting for progression to diabetes. METHODS:In 10,310 participants from the Atherosclerosis Risk in Communities (ARIC) Study (aged 46-70 years, ~55% women, ~20% Black adults) without diabetes at baseline (1990-1992), we used Cox regression to characterise age- and sex-adjusted associations of prediabetes with ~30 year incidence of complications (composite and separately), including atherosclerotic CVD (ASCVD), heart failure, chronic kidney disease (CKD) and all-cause mortality before and after accounting for intervening incidence of diabetes, modelled as a time-varying variable. We calculated the excess risk of complications in prediabetes remaining after accounting for progression to diabetes. RESULTS:Of the 60% of adults with prediabetes at baseline, ~30% progressed to diabetes (median time to diabetes, 7 years). Over the maximum follow-up of ~30 years, there were 7069 events (1937 ASCVD, 2109 heart failure, 3288 CKD and 4785 deaths). Prediabetes was modestly associated with risk of any complication (HR 1.21 [95% CI 1.15, 1.27]) vs normoglycaemia. This association remained significant after accounting for progression to diabetes (HR 1.18 [95% CI 1.12, 1.24]) with 85% (95% CI 75, 94%) of the excess risk of any complication in prediabetes remaining. Results were similar for the individual complications. CONCLUSIONS/INTERPRETATION/CONCLUSIONS:Progression to diabetes explained less than one-quarter of the risks of clinical outcomes associated with prediabetes. Prediabetes contributes to the risk of clinical outcomes even without progression to diabetes.

AIMS/HYPOTHESIS/OBJECTIVE:39-47 mmol/mol [5.7-6.4%] or fasting glucose 5.6-6.9 mmol/l) is associated with elevated risks of microvascular and macrovascular complications. It is unknown to what extent these risks in prediabetes remain after accounting for progression to diabetes. METHODS:In 10,310 participants from the Atherosclerosis Risk in Communities (ARIC) Study (aged 46-70 years, ~55% women, ~20% Black adults) without diabetes at baseline (1990-1992), we used Cox regression to characterise age- and sex-adjusted associations of prediabetes with ~30 year incidence of complications (composite and separately), including atherosclerotic CVD (ASCVD), heart failure, chronic kidney disease (CKD) and all-cause mortality before and after accounting for intervening incidence of diabetes, modelled as a time-varying variable. We calculated the excess risk of complications in prediabetes remaining after accounting for progression to diabetes. RESULTS:Of the 60% of adults with prediabetes at baseline, ~30% progressed to diabetes (median time to diabetes, 7 years). Over the maximum follow-up of ~30 years, there were 7069 events (1937 ASCVD, 2109 heart failure, 3288 CKD and 4785 deaths). Prediabetes was modestly associated with risk of any complication (HR 1.21 [95% CI 1.15, 1.27]) vs normoglycaemia. This association remained significant after accounting for progression to diabetes (HR 1.18 [95% CI 1.12, 1.24]) with 85% (95% CI 75, 94%) of the excess risk of any complication in prediabetes remaining. Results were similar for the individual complications. CONCLUSIONS/INTERPRETATION/CONCLUSIONS:Progression to diabetes explained less than one-quarter of the risks of clinical outcomes associated with prediabetes. Prediabetes contributes to the risk of clinical outcomes even without progression to diabetes.

BACKGROUND/UNASSIGNED:The prevalence of hypertension and uncontrolled hypertension may differ by age and sex. METHODS/UNASSIGNED:We included participants in the Atherosclerosis Risk in Communities study at seven study visits over 33 years (visit 1: 15 636 participants; mean age, 54 years; 55% women), estimating sex differences in prevalence of hypertension (systolic blood pressure ≥130 mm Hg; diastolic blood pressure ≥80 mm Hg; or self-reported antihypertension medication use) and uncontrolled hypertension (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg) using unadjusted and comorbidity-adjusted models. RESULTS/UNASSIGNED: CONCLUSIONS/UNASSIGNED:Sex differences in the prevalence of hypertension and uncontrolled hypertension vary by age, with the latter having implications for health throughout the life course.

RATIONALE & OBJECTIVE/OBJECTIVE:Exposure to extreme heat events has been linked to increased morbidity and mortality in the general population. Patients receiving maintenance dialysis may be vulnerable to greater risks from these events, but this is not well understood. We sought to characterize the association of extreme heat events and the risk of death among patients receiving dialysis in the United States. STUDY DESIGN/METHODS:Retrospective cohort study. SETTING & PARTICIPANTS/METHODS:Data from the United States Renal Data System were used to identify adults living in US urban settlements prone to extreme heat who initiated maintenance dialysis between 1997 and 2016. EXPOSURE/METHODS:An extreme heat event was defined as a time-updated heat index (a humid-heat metric) exceeding 40.6°C for ≥2 days or 46.1°C for ≥1 day. OUTCOME/RESULTS:Death. ANALYTICAL APPROACH/METHODS:Cox proportional hazards regression to estimate the elevation in risk of death during a humid-heat event adjusted for age, sex, year of dialysis initiation, dialysis modality, poverty level, and climate region. Interactions between humid-heat and these same factors were explored. RESULTS:Among 945,251 adults in 245 urban settlements, the mean age was 63 years and 44% were female. During a median follow-up of 3.6 years, 498,049 adults were exposed to at least one of 7,154 extreme humid-heat events, and 500,025 deaths occurred. In adjusted models, there was an increased risk of death (hazard ratio 1.18; 95% confidence interval 1.15-1.20) during extreme humid-heat exposure. Relative mortality risk was higher among patients living in the Southeast (P<0.001) compared with the Southwest. LIMITATIONS/CONCLUSIONS:Possibility of exposure misclassification, did not account for land use and air pollution co-exposures. CONCLUSIONS:This study suggests that patients receiving dialysis face an increased risk of death during extreme humid-heat exposure.