Chronic Kidney Disease Stage and Cardiovascular and Mortality Events Among Older Adults: The SPRINT Trial.

Rationale & Objective: The risk implications of the Kidney Disease: Improving Global Outcomes (KDIGO) chronic kidney disease classification in older adults are controversial. We evaluated the risk of adverse outcomes in this population across categories of estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (UACR). Study Design: Prospective cohort. Settings & Participants: In total, 2,509 participants aged ≥75 years in the Systolic Blood Pressure Intervention Trial (SPRINT). Exposure: KDIGO eGFR and UACR categories. We combined KDIGO categories G1 and G2, G3b and G4, as well as A2 and A3. Outcomes: Primary SPRINT outcome (composite of myocardial infarction, other acute coronary syndromes, stroke, heart failure, or death from cardiovascular causes), and all-cause death. Analytical Approach: Multivariable Cox proportional hazard models. Results: Mean age was 79.8 years, and 37.4% were female. The mean eGFR was 64.0 mL/min/1.73 m2, and the median UACR was 13.1 mg/g. In multivariable Cox proportional hazard analysis, compared with participants with eGFR ≥ 60 mL/min/1.73 m2 and UACR < 30 mg/g, there was no statistically significant difference in the risk of the primary outcome among participants with eGFR 45-59 or 15-44 mL/min/1.73 m2 and UACR < 30 mg/g. However, those with eGFR 45-59 or 15-44 mL/min/1.73 m2 and UACR ≥ 30 mg/g had higher risk of the primary outcome (HR [95% CI], 1.97 [1.27-3.04] and 3.32 [2.23-4.93], respectively). The risk for all-cause death was higher for each category of abnormal eGFR and UACR, with the highest risk observed among those with eGFR 15-44 mL/min/1.73 m2 and UACR ≥ 30 mg/g (3.34 [2.05-5.44]). Limitations: Individuals with diabetes and urine protein >1 g/day were excluded from SPRINT. Conclusion: Among older adults SPRINT participants, low eGFR without albuminuria was associated with higher mortality but not with increased risk of cardiovascular events. Additional studies are needed to evaluate an adapted chronic kidney disease stage-based risk stratification for older adults.

Using data from participants in the SPRINT trial, we evaluated the association of chronic kidney disease stage with adverse clinical outcomes among adults older than 75 years without diabetes. We found that low level of kidney function determined by a low estimated glomerular filtration rate with moderately or severely increased urine albumin excretion was associated with increased risk for cardiovascular events and all-cause mortality. However, low estimated glomerular filtration rate with normal or mildly increased urinary albumin excretion was not consistently associated with these adverse outcomes. This finding supports the need for additional studies to evaluate an age-adapted classification of chronic kidney disease to improve risk stratification among older adults.

Depressive Symptoms, Antidepressants, and Clinical Outcomes in Chronic Kidney Disease: Findings from the CRIC Study.

Rationale & Objective: The extent to which depression affects the progression of chronic kidney disease (CKD) and leads to adverse clinical outcomes remains inadequately understood. We examined the association of depressive symptoms (DS) and antidepressant medication use on clinical outcomes in 4,839 adults with nondialysis CKD. Study Design: Observational cohort study. Setting and Participants: Adults with mild to moderate CKD who participated in the multicenter Chronic Renal Insufficiency Cohort Study (CRIC). Exposure: The Beck Depression Inventory (BDI) was used to quantify DS. Antidepressant use was identified from medication bottles and prescription lists. Individual effects of DS and antidepressants were examined along with categorization as follows: (1) BDI <11 and no antidepressant use, (2) BDI <11 with antidepressant use, (3) BDI ≥11 and no antidepressant use, and (4) BDI ≥11 with antidepressant use. Outcomes: CKD progression, incident cardiovascular disease composite, all-cause hospitalizations, and mortality. Analytic Approach: Cox regression models were fitted for outcomes of CKD progression, incident cardiovascular disease, and all-cause mortality, whereas hospitalizations used Poisson regression. Results: At baseline, 27.3% of participants had elevated DS, and 19.7% used antidepressants. Elevated DS at baseline were associated with significantly greater risk for an incident cardiovascular disease event, hospitalization, and all-cause mortality, but not CKD progression, adjusted for antidepressants. Antidepressant use was associated with higher risk for all-cause mortality and hospitalizations, after adjusting for DS. Compared to participants without elevated DS and not using antidepressants, the remaining groups (BDI <11 with antidepressants; BDI ≥11 and no antidepressants; BDI ≥11 with antidepressants) showed higher risks of hospitalization and all-cause mortality. Limitations: Inability to infer causality among depressive symptoms, antidepressants, and outcomes. Additionally, the absence of nonpharmacological data, and required exploration of generalizability and alternative analytical approaches. Conclusions: Elevated DS increased adverse outcome risk in nondialysis CKD, unattenuated by antidepressants. Additionally, investigation into the utilization and counterproductivity of antidepressants in this population is warranted.

We analyzed data from 4,839 nondialysis chronic kidney disease (CKD) patients in the Chronic Renal Insufficiency Cohort Study to explore how depression and antidepressants affect CKD-related outcomes. Using the Beck Depression Inventory (BDI), we assessed depressive symptoms (DS) and identified antidepressant use through medication records. Outcomes included CKD progression, cardiovascular events, hospitalizations, and mortality. Elevated DS at baseline raised the risk of cardiovascular events, hospitalizations, and mortality, regardless of antidepressant use. Antidepressant use alone was associated with higher mortality and hospitalization risks. In comparison to those without elevated DS and no antidepressant use, all other groups faced increased hospitalization and mortality risks. Elevated DS posed a significant risk to nondialysis CKD patients, and antidepressants did not mitigate this risk.

Prevalence of infertility and pregnancy loss among individuals with kidney disease in the Hispanic Community Health Study/Study of Latinos.

BACKGROUND: Hispanic/Latino individuals are less likely to receive optimal treatment for chronic kidney disease than non-Hispanic whites. This may be particularly detrimental for women of reproductive age as chronic kidney disease increases risk for infertility, menstrual irregularities, and pregnancy loss. While these maternal outcomes have been associated with advanced chronic kidney disease, their occurrence in early chronic kidney disease is unclear. OBJECTIVES/DESIGN: Using baseline (2008-2011) and second study visit (2014-2017) data from the Hispanic Community Health Study/Study of Latinos, we retrospectively assessed the prevalence of chronic kidney disease as well as the association between chronic kidney disease and self-reported infertility, cessation of menses, hysterectomy, and nonviable pregnancy loss (experienced at less than 24 weeks gestation) in women of reproductive age (18-45 years). METHODS: Multivariable survey logistic regression analyses determined the unadjusted and multivariable-adjusted prevalence odds ratios with 95% confidence intervals between chronic kidney disease and the separate outcomes. RESULTS: Among 2589 Hispanic/Latino women included (mean age = 31.4 years), 4.6% were considered to have chronic kidney disease. In adjusted analyses, women with chronic kidney disease did not have a significantly increased odds of infertility (odds ratio = 1.02, 95% confidence interval = 0.42-2.49), cessation of menses (odds ratio = 1.25, 95% confidence interval = 0.52-3.04), or hysterectomy (odds ratio = 1.17, 95% confidence interval = 0.61-2.25) compared to those without chronic kidney disease. In those with chronic kidney disease, the adjusted odds of a nonviable pregnancy loss occurring after baseline visit were increased (odds ratio = 2.11, 95% confidence interval = 0.63-7.02) but not statistically significance. CONCLUSION: The presence of early stage chronic kidney disease did not confer a significant risk of infertility, cessation of menses, or nonviable pregnancy loss.

The Hispanic Community Health Study/Study of Latinos is a population-based study of over 16,000 Hispanic/Latino individuals throughout the United States. Within this cohort, we assessed the prevalence of chronic kidney disease in women of reproductive age (18­45 years old) and the associations between kidney disease and infertility, cessation of menses, and nonviable pregnancy loss (loss occurring before the 24th week of pregnancy). We found that kidney disease affected 1 in 20 women of reproductive age and those with kidney disease were more likely to have obesity, diabetes, and hypertension. Compared to those without kidney disease, the presence of kidney disease did not increase risk of infertility, cessation of menses, or nonviable pregnancy loss.

Frailty and Cardiovascular Outcomes in Adults With CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes in adults with kidney failure requiring dialysis. However, this relationship has not been thoroughly evaluated among those with non-dialysis-dependent CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,539 adults in the Chronic Renal Insufficiency Cohort Study. EXPOSURE: Frailty status assessed using 5 criteria: slow gait speed, muscle weakness, low physical activity, exhaustion, and unintentional weight loss. OUTCOME: Atherosclerotic events, incident heart failure, all-cause death, and cardiovascular death. ANALYTICAL APPROACH: Cause-specific hazards models. RESULTS: At study entry, the participants' mean age was 62 years, 46% were female, the mean estimated glomerular filtration rate was 45.4mL/min/1.73m2, and the median urine protein was 0.2mg/day. Frailty status was as follows: 12% frail, 51% prefrail, and 37% nonfrail. Over a median follow-up of 11.4 years, there were 393 atherosclerotic events, 413 heart failure events, 497 deaths, and 132 cardiovascular deaths. In multivariable regression analyses, compared with nonfrailty, both frailty and prefrailty status were each associated with higher risk of an atherosclerotic event (HR, 2.03 [95% CI, 1.41-2.91] and 1.77 [95% CI, 1.35-2.31], respectively) and incident heart failure (HR, 2.22 [95% CI, 1.59-3.10] and 1.39 [95% CI, 1.07-1.82], respectively), as well as higher risk of all-cause death (HR, 2.52 [95% CI, 1.84-3.45] and 1.76 [95% CI, 1.37-2.24], respectively) and cardiovascular death (HR, 3.01 [95% CI, 1.62-5.62] and 1.78 [95% 1.06-2.99], respectively). LIMITATIONS: Self-report of aspects of the frailty assessment and comorbidities, which may have led to bias in some estimates. CONCLUSIONS: In adults with CKD, frailty status was associated with higher risk of cardiovascular events and mortality. Future studies are needed to evaluate the impact of interventions to reduce frailty on cardiovascular outcomes in this population. PLAIN-LANGUAGE SUMMARY: Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes. We sought to evaluate the association of frailty status with cardiovascular events and death in adults with CKD. Frailty was assessed according to the 5 phenotypic criteria detailed by Fried and colleagues. Among 2,539 participants in the CRIC Study, we found that 12% were frail, 51% were prefrail, and 37% were nonfrail. Frailty status was associated with an increased risk of atherosclerotic events, incident heart failure, and death.

Adherence to Plant-Based Diets and Risk of CKD Progression and All-Cause Mortality: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Studies have shown that generally healthy individuals who consume diets rich in plant foods have a lower risk of incident chronic kidney disease (CKD) and cardiovascular disease. This study investigated the prospective associations of plant-based diets with the risk of CKD progression and all-cause mortality in individuals with CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,539 participants with CKD recruited between 2003-2008 into the Chronic Renal Insufficiency Cohort (CRIC) Study. EXPOSURE: Responses on the Diet History Questionnaire were used to calculate scores for the overall plant-based diet index, healthy plant-based diet index, and unhealthy plant-based diet index. OUTCOME: (1) CKD progression defined as≥50% estimated glomerular filtration rate decline from baseline or kidney replacement therapy (dialysis, transplant) and (2) all-cause mortality. ANALYTICAL APPROACH: Cox proportional hazards models to compute hazard ratios and 95% confidence intervals adjusting for lifestyle, socioeconomic, and clinical covariates. RESULTS: There were 977 CKD progression events and 836 deaths during a median follow-up period of 7 and 12 years, respectively. Participants with the highest versus lowest adherence to overall plant-based diets and healthy plant-based diets had 26% (HR, 0.74 [95% CI, 0.62-0.88], P trend<0.001) and 21% (HR, 0.79 [95% CI, 0.66-0.95], P trend=0.03) lower risks of all-cause mortality, respectively. Each 10-point higher score of unhealthy plant-based diets was modestly associated with a higher risk of CKD progression (HR, 1.14 [95% CI, 1.03-1.25) and all-cause mortality (HR, 1.11 [95% CI, 1.00-1.23). LIMITATIONS: Self-reported diet may be subject to measurement error. CONCLUSIONS: Adherence to an overall plant-based diet and a healthy plant-based diet is associated with a reduced risk of all-cause mortality among individuals with CKD. An unhealthy plant-based was associated with an elevated risk of CKD progression and all-cause mortality. PLAIN-LANGUAGE SUMMARY: Plant-based diets are healthful dietary patterns that have been linked to a lower risk of chronic diseases. However, the impact of plant-based diets on clinical outcomes in patients with chronic kidney disease (CKD) is not well established. In 2,539 individuals with CKD, we examined the associations of adherence to 3 different types of plant-based diets with the risks of CKD progression and all-cause mortality. We found that following an overall plant-based diet and a healthy plant-based diet was associated with a lower risk of all-cause mortality. By contrast, following an unhealthy plant-based diet was associated with a higher risk of CKD progression and all-cause mortality. These results suggest that the quality of plant-based diets may be important for CKD management.

Risk for Chronic Kidney Disease Progression After Acute Kidney Injury: Findings From the Chronic Renal Insufficiency Cohort Study.

BACKGROUND: Prior studies associating acute kidney injury (AKI) with more rapid subsequent loss of kidney function had methodological limitations, including inadequate control for differences between patients who had AKI and those who did not. OBJECTIVE: To determine whether AKI is independently associated with subsequent kidney function trajectory among patients with chronic kidney disease (CKD). DESIGN: Multicenter prospective cohort study. SETTING: United States. PARTICIPANTS: Patients with CKD (n = 3150). MEASUREMENTS: Hospitalized AKI was defined by a 50% or greater increase in inpatient serum creatinine (SCr) level from nadir to peak. Kidney function trajectory was assessed using estimated glomerular filtration rate (eGFR) based on SCr level (eGFRcr) or cystatin C level (eGFRcys) measured at annual study visits. RESULTS: During a median follow-up of 3.9 years, 433 participants had at least 1 AKI episode. Most episodes (92%) had stage 1 or 2 severity. There were decreases in eGFRcr (-2.30 [95% CI, -3.70 to -0.86] mL/min/1.73 m2) and eGFRcys (-3.61 [CI, -6.39 to -0.82] mL/min/1.73 m2) after AKI. However, in fully adjusted models, the decreases were attenuated to -0.38 (CI, -1.35 to 0.59) mL/min/1.73 m2 for eGFRcr and -0.15 (CI, -2.16 to 1.86) mL/min/1.73 m2 for eGFRcys, and the CI bounds included the possibility of no effect. Estimates of changes in eGFR slope after AKI determined by either SCr level (0.04 [CI, -0.30 to 0.38] mL/min/1.73 m2 per year) or cystatin C level (-0.56 [CI, -1.28 to 0.17] mL/min/1.73 m2 per year) also had CI bounds that included the possibility of no effect. LIMITATIONS: Few cases of severe AKI, no adjudication of AKI cause, and lack of information about nephrotoxic exposures after hospital discharge. CONCLUSION: After pre-AKI eGFR, proteinuria, and other covariables were accounted for, the association between mild to moderate AKI and worsening subsequent kidney function in patients with CKD was small. PRIMARY FUNDING SOURCE: National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.

Ideal Cardiovascular Health in Mexican Adults with CKD Living in Mexico City Versus Chicago.

Evidence suggests that Mexican adults living in Mexico have a more favorable cardiovascular risk profile than Mexican adults living in the U.S. However, this relationship has not been evaluated among patients with chronic kidney disease (CKD), which is a question of importance given the high risk for cardiovascular disease among patients with CKD. Using data from two ongoing observational cohort studies, we compared the prevalence of ideal cardiovascular health metrics (assessed by the American Heart Association "Life's Simple 7" criteria) in 309 Mexican adults with CKD living in Mexico City to 343 Mexican adults with CKD living in Chicago. Mexican adults with CKD living in Mexico City had a significantly higher prevalence of ideal body mass index (25 vs. 10%), diet (17 vs. 8%), total cholesterol (80 vs. 63%), blood pressure (43 vs. 25%), and fasting glucose (54 vs. 42%). Mexican adults with CKD living in both Mexico City and Chicago had low levels of cardiovascular health scores. Future work is needed to better understand the lower prevalence of ideal cardiovascular health metrics in Chicago as compared to Mexico City.

Trends and perspectives for improving quality of chronic kidney disease care: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference.

Chronic kidney disease (CKD) affects over 850 million people globally, and the need to prevent its development and progression is urgent. During the past decade, new perspectives have arisen related to the quality and precision of care for CKD, owing to the development of new tools and interventions for CKD diagnosis and management. New biomarkers, imaging methods, artificial intelligence techniques, and approaches to organizing and delivering healthcare may help clinicians recognize CKD, determine its etiology, assess the dominant mechanisms at given time points, and identify patients at high risk for progression or related events. As opportunities to apply the concepts of precision medicine for CKD identification and management continue to be developed, an ongoing discussion of the potential implications for care delivery is required. The 2022 KDIGO Controversies Conference on Improving CKD Quality of Care: Trends and Perspectives examined and discussed best practices for improving the precision of CKD diagnosis and prognosis, managing the complications of CKD, enhancing the safety of care, and maximizing patient quality of life. Existing tools and interventions currently available for the diagnosis and treatment of CKD were identified, with discussion of current barriers to their implementation and strategies for improving the quality of care delivered for CKD. Key knowledge gaps and areas for research were also identified.

The Kidney Failure Risk Equation: Evaluation of Novel Input Variables including eGFR Estimated Using the CKD-EPI 2021 Equation in 59 Cohorts.

SIGNIFICANCE STATEMENT: The kidney failure risk equation (KFRE) uses age, sex, GFR, and urine albumin-to-creatinine ratio (ACR) to predict 2- and 5-year risk of kidney failure in populations with eGFR <60 ml/min per 1.73 m 2 . However, the CKD-EPI 2021 creatinine equation for eGFR is now recommended for use but has not been fully tested in the context of KFRE. In 59 cohorts comprising 312,424 patients with CKD, the authors assessed the predictive performance and calibration associated with the use of the CKD-EPI 2021 equation and whether additional variables and accounting for the competing risk of death improves the KFRE's performance. The KFRE generally performed well using the CKD-EPI 2021 eGFR in populations with eGFR <45 ml/min per 1.73 m 2 and was not improved by adding the 2-year prior eGFR slope and cardiovascular comorbidities. BACKGROUND: The kidney failure risk equation (KFRE) uses age, sex, GFR, and urine albumin-to-creatinine ratio (ACR) to predict kidney failure risk in people with GFR <60 ml/min per 1.73 m 2 . METHODS: Using 59 cohorts with 312,424 patients with CKD, we tested several modifications to the KFRE for their potential to improve the KFRE: using the CKD-EPI 2021 creatinine equation for eGFR, substituting 1-year average ACR for single-measure ACR and 1-year average eGFR in participants with high eGFR variability, and adding 2-year prior eGFR slope and cardiovascular comorbidities. We also assessed calibration of the KFRE in subgroups of eGFR and age before and after accounting for the competing risk of death. RESULTS: The KFRE remained accurate and well calibrated overall using the CKD-EPI 2021 eGFR equation. The other modifications did not improve KFRE performance. In subgroups of eGFR 45-59 ml/min per 1.73 m 2 and in older adults using the 5-year time horizon, the KFRE demonstrated systematic underprediction and overprediction, respectively. We developed and tested a new model with a spline term in eGFR and incorporating the competing risk of mortality, resulting in more accurate calibration in those specific subgroups but not overall. CONCLUSIONS: The original KFRE is generally accurate for eGFR <45 ml/min per 1.73 m 2 when using the CKD-EPI 2021 equation. Incorporating competing risk methodology and splines for eGFR may improve calibration in low-risk settings with longer time horizons. Including historical averages, eGFR slopes, or a competing risk design did not meaningfully alter KFRE performance in most circumstances.

A generalized covariate-adjusted top-scoring pair algorithm with applications to diabetic kidney disease stage classification in the Chronic Renal Insufficiency Cohort (CRIC) Study.

BACKGROUND: The growing amount of high dimensional biomolecular data has spawned new statistical and computational models for risk prediction and disease classification. Yet, many of these methods do not yield biologically interpretable models, despite offering high classification accuracy. An exception, the top-scoring pair (TSP) algorithm derives parameter-free, biologically interpretable single pair decision rules that are accurate and robust in disease classification. However, standard TSP methods do not accommodate covariates that could heavily influence feature selection for the top-scoring pair. Herein, we propose a covariate-adjusted TSP method, which uses residuals from a regression of features on the covariates for identifying top scoring pairs. We conduct simulations and a data application to investigate our method, and compare it to existing classifiers, LASSO and random forests. RESULTS: Our simulations found that features that were highly correlated with clinical variables had high likelihood of being selected as top scoring pairs in the standard TSP setting. However, through residualization, our covariate-adjusted TSP was able to identify new top scoring pairs, that were largely uncorrelated with clinical variables. In the data application, using patients with diabetes (n = 977) selected for metabolomic profiling in the Chronic Renal Insufficiency Cohort (CRIC) study, the standard TSP algorithm identified (valine-betaine, dimethyl-arg) as the top-scoring metabolite pair for classifying diabetic kidney disease (DKD) severity, whereas the covariate-adjusted TSP method identified the pair (pipazethate, octaethylene glycol) as top-scoring. Valine-betaine and dimethyl-arg had, respectively, ≥ 0.4 absolute correlation with urine albumin and serum creatinine, known prognosticators of DKD. Thus without covariate-adjustment the top-scoring pair largely reflected known markers of disease severity, whereas covariate-adjusted TSP uncovered features liberated from confounding, and identified independent prognostic markers of DKD severity. Furthermore, TSP-based methods achieved competitive classification accuracy in DKD to LASSO and random forests, while providing more parsimonious models. CONCLUSIONS: We extended TSP-based methods to account for covariates, via a simple, easy to implement residualizing process. Our covariate-adjusted TSP method identified metabolite features, uncorrelated from clinical covariates, that discriminate DKD severity stage based on the relative ordering between two features, and thus provide insights into future studies on the order reversals in early vs advanced disease states.

Prospective associations of health literacy with clinical outcomes in adults with CKD: findings from the CRIC study.

BACKGROUND: Limited health literacy is associated with significant morbidity and mortality in the general population but the relation of health literacy with long-term clinical outcomes among adults with chronic kidney disease (CKD) is less clear. METHODS: Prospective data from the Chronic Renal Insufficiency Cohort (CRIC) Study (n = 3715) were used. Health literacy was assessed with the Short Test of Functional Health Literacy in Adults (dichotomized as limited/adequate). Cox proportional hazards models were used to separately examine the relations of health literacy with CKD progression, cardiovascular event (any of the following: myocardial infarction, congestive heart failure, stroke or peripheral artery disease), and all-cause, cardiovascular and non-cardiovascular mortality. Poisson regression was used to assess the health literacy-hospitalization association. Models were sequentially adjusted: Model 1 adjusted for potential confounders (sociodemographic factors), while Model 2 additionally adjusted for potential mediators (clinical and lifestyle factors) of the associations of interest. RESULTS: In confounder-adjusted models, participants with limited (vs adequate) health literacy [555 (15%)] had an increased risk of CKD progression [hazard ratio (HR) 1.34; 95% confidence interval (CI) 1.06-1.71], cardiovascular event (HR 1.67; 95% CI 1.39-2.00), hospitalization (rate ratio 1.33; 95% CI 1.26-1.40), and all-cause (HR 1.54; 95% CI 1.27-1.86), cardiovascular (HR 2.39; 95% CI 1.69-3.38) and non-cardiovascular (HR 1.27; 95% CI 1.01-1.60) mortality. Additional adjustments for potential mediators (Model 2) showed similar results except that the relations of health literacy with CKD progression and non-cardiovascular mortality were no longer statistically significant. CONCLUSIONS: In the CRIC Study, adults with limited (vs adequate) health literacy had a higher risk for CKD progression, cardiovascular event, hospitalization and mortality-regardless of adjustment for potential confounders.

Sleep, cardiovascular risk factors, and kidney function: The Multi-Ethnic Study of Atherosclerosis (MESA).

OBJECTIVES: Examine the associations of sleep measures with kidney function changes over time among individuals from a community-based study. METHODS: The sample includes 1657 participants (287 with chronic kidney disease [CKD]) in the Multi-Ethnic Study of Atherosclerosis Sleep Cohort (mean age: 57.7 years, male: 46.0%). We examined associations between a large set of sleep variables (polysomnography, actigraphy, and questionnaires) and cardiovascular disease risk factors and changes in estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio over approximately 5 years using high-dimensional regression. We investigated the modifying effect of sleep on the associations between cardiovascular disease risk factors and kidney function. RESULTS: Sleep metrics predicted kidney function decline only among individuals with baseline CKD. Among this group, eGFR decline was associated with decreased stage N3 sleep (0.32 mL/min/1.73 m2/y per 10% decrease in N3, p < .001); increased actigraphy napping frequency (beta: -0.20 [-0.30, -0.07]); and actigraphy sleep midpoint trajectory in early morning (ref: midnight, beta: -0.84 [-1.19, -0.50]). Urinary albumin-to-creatinine ratio increase was associated with high wake bouts trajectory (ref: low, beta: 0.97 [0.28, 1.67]) and increased sleep-related hypoxemia (oxygen saturation %time<90 [≥5%], beta: 2.17 [1.26, 3.08]). Sleep metrics--N3 sleep, naps, and midpoint trajectory--significantly modified associations between hemoglobin A1C and eGFR decline. CONCLUSIONS: Reduced deep sleep, daytime napping, increased wake bouts, delayed sleep rhythms, and overnight hypoxemia are associated with longitudinal kidney function decline, with effects most apparent in individuals with CKD. Deep sleep, napping, and sleep timing modified the association between hemoglobin A1C and kidney function.

Absence of long-term changes in urine biomarkers after AKI: findings from the CRIC study.

BACKGROUND: Mechanisms by which AKI leads to CKD progression remain unclear. Several urine biomarkers have been identified as independent predictors of progressive CKD. It is unknown whether AKI may result in long-term changes in these urine biomarkers, which may mediate the effect of AKI on CKD progression. METHODS: We selected 198 episodes of hospitalized AKI (defined as peak/nadir inpatient serum creatinine values ≥ 1.5) among adult participants in the Chronic Renal Insufficiency Cohort (CRIC) Study. We matched the best non-AKI hospitalization (unique patients) for each AKI hospitalization using pre-hospitalization characteristics including eGFR and urine protein/creatinine ratio. Biomarkers were measured in banked urine samples collected at annual CRIC study visits. RESULTS: Urine biomarker measurements occurred a median of 7 months before and 5 months after hospitalization. There were no significant differences in the change in urine biomarker-to-creatinine ratio between the AKI and non-AKI groups: KIM-1/Cr + 9% vs + 7%, MCP-1/Cr + 4% vs + 1%, YKL-40/Cr + 7% vs -20%, EGF/Cr -11% vs -8%, UMOD/Cr -2% vs -7% and albumin/Cr + 17% vs + 13% (all p > 0.05). CONCLUSION: In this cohort of adults with CKD, AKI did not associate with long-term changes in urine biomarkers.

Vitamin K Status and Cognitive Function in Adults with Chronic Kidney Disease: The Chronic Renal Insufficiency Cohort.

Vitamin K is linked to cognitive function, but studies in individuals with chronic kidney disease (CKD), who are at risk for vitamin K insufficiency and cognitive impairment, are lacking. The cross-sectional association of vitamin K status biomarkers with cognitive performance was evaluated in ≥55-y-old adults with CKD (N = 714, 49% female, 44% black). A composite score of a cognitive performance test battery, calculated by averaging the z scores of the individual tests, was the primary outcome. Vitamin K status was measured using plasma phylloquinone and dephospho-uncarboxylated matrix Gla protein [(dp)ucMGP]. Participants with low plasma (dp)ucMGP, reflecting higher vitamin K status, had better cognitive performance than those in the two higher (dp)ucMGP categories based on the composite outcome (P = 0.03), whereas it did not significantly differ according to plasma phylloquinone categories (P = 0.08). Neither biomarker was significantly associated with performance on individual tests (all P > 0.05). The importance of vitamin K to cognitive performance in adults with CKD remains to be clarified.

Development and Validation of Prediction Models of Adverse Kidney Outcomes in the Population With and Without Diabetes.

OBJECTIVE: To predict adverse kidney outcomes for use in optimizing medical management and clinical trial design. RESEARCH DESIGN AND METHODS: In this meta-analysis of individual participant data, 43 cohorts (N = 1,621,817) from research studies, electronic medical records, and clinical trials with global representation were separated into development and validation cohorts. Models were developed and validated within strata of diabetes mellitus (presence or absence) and estimated glomerular filtration rate (eGFR; ≥60 or <60 mL/min/1.73 m2) to predict a composite of ≥40% decline in eGFR or kidney failure (i.e., receipt of kidney replacement therapy) over 2-3 years. RESULTS: There were 17,399 and 24,591 events in development and validation cohorts, respectively. Models predicting ≥40% eGFR decline or kidney failure incorporated age, sex, eGFR, albuminuria, systolic blood pressure, antihypertensive medication use, history of heart failure, coronary heart disease, atrial fibrillation, smoking status, and BMI, and, in those with diabetes, hemoglobin A1c, insulin use, and oral diabetes medication use. The median C-statistic was 0.774 (interquartile range [IQR] = 0.753, 0.782) in the diabetes and higher-eGFR validation cohorts; 0.769 (IQR = 0.758, 0.808) in the diabetes and lower-eGFR validation cohorts; 0.740 (IQR = 0.717, 0.763) in the no diabetes and higher-eGFR validation cohorts; and 0.750 (IQR = 0.731, 0.785) in the no diabetes and lower-eGFR validation cohorts. Incorporating the previous 2-year eGFR slope minimally improved model performance, and then only in the higher-eGFR cohorts. CONCLUSIONS: Novel prediction equations for a decline of ≥40% in eGFR can be applied successfully for use in the general population in persons with and without diabetes with higher or lower eGFR.

Self-reported Physical Activity and Cardiovascular Events in Adults With CKD: Findings From the CRIC (Chronic Renal Insufficiency Cohort) Study.

RATIONALE & OBJECTIVE: In the general population, there is an association between higher levels of physical activity and lower risk for cardiovascular events and mortality, but this relationship has not been well evaluated in chronic kidney disease (CKD). We investigated the association between self-reported physical activity and outcomes in a CKD cohort. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 3,926 participants in the Chronic Renal Insufficiency Cohort (CRIC) Study. EXPOSURE: Time-updated self-reported physical activity assessed by (1) quartile of moderate-to-vigorous physical activity (MVPA) and (2) meeting guideline-recommended level of physical activity (categorized as active, meeting guidelines; active, not meeting guidelines; or inactive). OUTCOME: Atherosclerotic events (myocardial infarction, stroke, or peripheral artery disease), incident heart failure, and all-cause and cardiovascular death. ANALYTICAL APPROACH: Cox proportional hazards regression. RESULTS: At baseline, compared with the lowest MVPA quartile, those in the highest quartile were more likely to be younger, male, not have prevalent cardiovascular disease, and have higher estimated glomerular filtration rate. Overall, 51% met the physical activity guidelines; of those who did not, 30% were inactive. During the median follow-up period of 13.4 years, there were 772 atherosclerotic events, 848 heart failure events, and 1,553 deaths, and 420 cardiovascular deaths. Compared with the participants in the lowest MVPA quartile, the highest quartile had a lower risk of atherosclerotic events (HR, 0.64 [95% CI, 0.51-0.79]), incident heart failure (HR, 0.71 [95% CI, 0.58-0.87]), and all-cause and cardiovascular death (HRs of 0.54 [95% CI, 0.46-0.63] and 0.47 [95% CI, 0.35-0.64], respectively). The findings were similar for analyses evaluating recommended level of physical activity. LIMITATIONS: Self-reported physical activity may result in some degree of misclassification. CONCLUSIONS: Higher self-reported physical activity was associated with lower risk of cardiovascular events and mortality in CKD patients, which may have important implications for clinical practice and the design of interventional studies. PLAIN-LANGUAGE SUMMARY: In this long-term study of 3,926 adults with chronic kidney disease, we found that individuals with higher levels of physical activity were less likely to experience an atherosclerotic event (for example, a heart attack, stroke, or peripheral arterial disease), new-onset heart failure, and death as compared with those with lower levels of physical activity. The findings were similar for the analyses evaluating adherence to guideline-recommended level of physical activity (that is, for more than 150 minutes per week), and they strengthen the evidence supporting the current guideline recommendations.

Hispanic ethnicity and mortality among critically ill patients with COVID-19.

BACKGROUND: Hispanic persons living in the United States (U.S.) are at higher risk of infection and death from coronavirus disease 2019 (COVID-19) compared with non-Hispanic persons. Whether this disparity exists among critically ill patients with COVID-19 is unknown. OBJECTIVE: To evaluate ethnic disparities in mortality among critically ill adults with COVID-19 enrolled in the Study of the Treatment and Outcomes in Critically Ill Patients with COVID-19 (STOP-COVID). METHODS: Multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICU) at 67 U.S. hospitals from March 4 to May 9, 2020. Multilevel logistic regression was used to evaluate 28-day mortality across racial/ethnic groups. RESULTS: A total of 2153 patients were included (994 [46.2%] Hispanic and 1159 [53.8%] non-Hispanic White). The median (IQR) age was 62 (51-71) years (non-Hispanic White, 66 [57-74] years; Hispanic, 56 [46-67] years), and 1462 (67.9%) were men. Compared with non-Hispanic White patients, Hispanic patients were younger; were less likely to have hypertension, chronic obstructive pulmonary disease, coronary artery disease, or heart failure; and had longer duration of symptoms prior to ICU admission. During median (IQR) follow-up of 14 (7-24) days, 785 patients (36.5%) died. In analyses adjusted for age, sex, clinical characteristics, and hospital size, Hispanic patients had higher odds of death compared with non-Hispanic White patients (OR, 1.44; 95% CI, 1.12-1.84). CONCLUSIONS: Among critically ill adults with COVID-19, Hispanic patients were more likely to die than non-Hispanic White patients, even though they were younger and had lower comorbidity burden. This finding highlights the need to provide earlier access to care to Hispanic individuals with COVID-19, especially given our finding of longer duration of symptoms prior to ICU admission among Hispanic patients. In addition, there is a critical need to address ongoing disparities in post hospital discharge care for patients with COVID-19.