The difference between cystatin C- and creatinine-based assessment of kidney function in acute heart failure.

AIMS: Acute heart failure (HF) is associated with muscle mass loss, potentially leading to overestimation of kidney function using serum creatinine-based estimated glomerular filtration rate (eGFRsCr ). Cystatin C-based eGFR (eGFRCysC ) is less muscle mass dependent. Changes in the difference between eGFRCysC and eGFRsCr may reflect muscle mass loss. We investigated the difference between eGFRCysC and eGFRsCr and its association with clinical outcomes in acute HF patients. METHODS AND RESULTS: A post hoc analysis was performed in 841 patients enrolled in three trials: Diuretic Optimization Strategy Evaluation (DOSE), Renal Optimization Strategies Evaluation (ROSE), and Cardiorenal Rescue Study in Acute Decompensated Heart Failure (CARRESS-HF). Intra-individual differences between eGFRs (eGFRdiff ) were calculated as eGFRCysC -eGFRsCr at serial time points during HF admission. We investigated associations of (i) change in eGFRdiff between baseline and day 3 or 4 with readmission-free survival up to day 60; (ii) index hospitalization length of stay (LOS) and readmission with eGFRdiff at day 60. eGFRCysC reclassified 40% of samples to more advanced kidney dysfunction. Median eGFRdiff was -4 [-11 to 1.5] mL/min/1.73 m2 at baseline, became more negative during admission and remained significantly different at day 60. The change in eGFRdiff between baseline and day 3 or 4 was associated with readmission-free survival (adjusted hazard ratio per standard deviation decrease in eGFRdiff : 1.14, P = 0.035). Longer index hospitalization LOS and readmission were associated with more negative eGFRdiff at day 60 (both P ≤ 0.026 in adjusted models). CONCLUSIONS: In acute HF, a marked difference between eGFRCysC and eGFRsCr is present at baseline, becomes more pronounced during hospitalization, and is sustained at 60 day follow-up. The change in eGFRdiff during HF admission and eGFRdiff at day 60 are associated with clinical outcomes.

Rurality, Death, and Healthcare Utilization in Heart Failure in the Community.

Background Prior reports indicate that living in a rural area may be associated with worse health outcomes. However, data on rurality and heart failure (HF) outcomes are scarce. Methods and Results Residents from 6 southeastern Minnesota counties with a first-ever code for HF (International Classification of Diseases, Ninth Revision [ICD-9], code 428, and International Classification of Diseases, Tenth Revision [ICD-10] code I50) between January 1, 2013 and December 31, 2016, were identified. Resident address was classified according to the rural-urban commuting area codes. Rurality was defined as living in a nonmetropolitan area. Cox regression was used to analyze the association between living in a rural versus urban area and death; Andersen-Gill models were used for hospitalization and emergency department visits. Among 6003 patients with HF (mean age 74 years, 48% women), 43% lived in a rural area. Rural patients were older and had a lower educational attainment and less comorbidity compared with patients living in urban areas (P<0.001). After a mean (SD) follow-up of 2.8 (1.7) years, 2440 deaths, 20 506 emergency department visits, and 11 311 hospitalizations occurred. After adjustment, rurality was independently associated with an increased risk of death (hazard ratio [HR], 1.18; 95% CI, 1.09-1.29) and a reduced risk of emergency department visits (HR, 0.89; 95% CI, 0.82-0.97) and hospitalizations (HR, 0.78; 95% CI, 0.73-0.84). Conclusions Among patients with HF, living in a rural area is associated with an increased risk of death and fewer emergency department visits and hospitalizations. Further study to identify and address the mechanisms through which rural residence influences mortality and healthcare utilization in HF is needed in order to reduce disparities in rural health.

Increasing Mortality From Premature Coronary Artery Disease in Women in the Rural United States.

Background Previous reports have described a leveling off of mortality from premature coronary artery disease (CAD). In recent years, the prevalence of cardiovascular risk factors has increased in rural communities and young adults. Methods and Results We extracted CAD mortality rates from the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) database from 1999 to 2017, focusing on mortality from premature CAD (defined as <65 years of age in women) and urban-rural differences. Variations in mortality rates over time, assessed with Joinpoint regression modeling, are expressed as estimated annual percentage change (95% CI) and stratified by urbanization, sex, age, and race. Age-adjusted mortality rates decreased for women and men. Stratification by urbanization revealed that premature CAD mortality is stagnating among women in rural areas. However, this stagnation conceals a statistically significant increase in CAD mortality rates since 2009 in women aged 55 to 64 years (estimated annual percentage change: +1.4%; 95% CI, +0.3% to +2.5%) and since 1999 in women aged 45 to 54 years (estimated annual percentage change: +0.6%; 95% CI, +0.2% to 1.0%). Since 1999, mortality has been stagnating in the youngest group (aged 35-44 years; estimated annual percentage change: +0.2%; 95% CI, -0.4% to +0.8%). Stratification by race indicated an increase in mortality rates among white rural women. Premature CAD mortality remains consistently higher in the rural versus urban United States, regardless of sex, race, and age group. Conclusions Premature CAD mortality rates have declined over time. However, stratification by sex and urbanization reveals disparities that would otherwise remain concealed: CAD mortality rates have increased among women from rural areas since at least 2009.