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BACKGROUND The glomerular filtration rate (GFR) assesses the function of all nephrons, and the single-nephron GFR assesses the function of individual nephrons. How the single-nephron GFR relates to demographic and clinical characteristics and kidney-biopsy findings in humans is unknown. METHODS We identified 1388 living kidney donors at the Mayo Clinic and the Cleveland Clinic who underwent a computed tomographic (CT) scan of the kidney with the use of contrast material and an iothalamate-based measurement of the GFR during donor evaluation and who underwent a kidney biopsy at donation. The mean single-nephron GFR was calculated as the GFR divided by the number of nephrons (calculated as the cortical volume of both kidneys as assessed on CT times the biopsy-determined glomerular density). Demographic and clinical characteristics and biopsy findings were correlated with the single-nephron GFR. RESULTS A total of 58% of the donors were women, and the mean (±SD) age of the donors was 44±12 years. The mean GFR was 115±24 ml per minute, the mean number of nephrons was 860,000±370,000 per kidney, and the mean single-nephron GFR was 80±40 nl per minute. The single-nephron GFR did not vary significantly according to age (among donors <70 years of age), sex, or height (among donors ≤190 cm tall). A higher single-nephron GFR was independently associated with larger nephrons on biopsy and more glomerulosclerosis and arteriosclerosis than would be expected for age. A higher single-nephron GFR was associated with a height of more than 190 cm, obesity, and a family history of end-stage renal disease. CONCLUSIONS Among healthy adult kidney donors, the single-nephron GFR was fairly constant with regard to age, sex, and height (if ≤190 cm). A higher single-nephron GFR was associated with certain risk factors for chronic kidney disease and certain kidney-biopsy findings. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases.)

BACKGROUND & AIMS According to the National Center for Health Statistics (NCHS), chronic liver disease and cirrhosis is the 12th leading cause of death in the United States. However, this single descriptor might not adequately enumerate all deaths from liver disease. The aim of our study was to update data on liver mortality in the United States. METHODS Mortality data were obtained from the Rochester Epidemiology Project (1999–2008) and the National Death Registry (1979–2008). Liver-specific mortality values were calculated. In contrast to the narrow NCHS definition, updated liver-related causes of death included other specific liver diagnoses (eg, hepatorenal syndrome), viral hepatitis, and hepatobiliary cancers. RESULTS The Rochester Epidemiology Project database contained information on 261 liver-related deaths, with an age- and sex-adjusted death rate of 27.0/100,000 persons (95% confidence interval: 23.7–30.3). Of these, only 71 deaths (27.2%) would have been captured by the NCHS definition. Of cases for which viral hepatitis or hepatobiliary cancer was the cause of death, 96.9% and 94.3% had liver-related immediate causes of death, respectively. In analysis of data from the National Death registry (2008), use of the updated definition increased livermortality by>2-fold (from 11.7 to 25.7 deaths/100,000, respectively). Using NCHS definitions, liver-related deaths decreased from 18.9/100,000 in 1979 to 11.7/100,000 in 2008—a reduction of 38%. However, using the updated estimate, liver-related deaths were essentially unchanged from 1979 (25.8/100,000) to 2008 (25.7/100,000). Mortality burden was systematically under-estimated among non-whites and persons of Hispanic ethnicity. CONCLUSIONS Based on analyses of theRochester Epidemiology Project and National Death databases, liver-related mortality has been under-estimated during the past 2 decades in the United States.

Nonalcoholic fatty liver disease (NAFLD) is related to risk factors of coronary artery disease, such as dyslipidemia, diabetes, and metabolic syndrome, which are closely linked with visceral adiposity. The aim of this study was to investigate whether NAFLD was associated with coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis independent of computed tomography (CT)-measured visceral adiposity. Out of 5,648 subjects who visited one of health screening centers between 2003 and 2008, we enrolled 4,023 (mean age 56.9 ± 9.4 years, 60.7% males) subjects without known liver disease or a history of ischemic heart disease. CAC score was evaluated by the Agatston method. In univariate analyses, the presence of CAC (score >0) was significantly associated with age, sex, body mass index, aspartate aminotransferase, alanine aminotransferase, high-density lipoprotein cholesterol, triglycerides and increased odds of diabetes, hypertension, smoking, and NAFLD. Increasing CAC scores (0, <10, 10-100, ≥100) were associated with higher prevalence of NAFLD (OR 1.84, 95% CI 1.61-2.10, P<0.001). Multivariate ordinal regression analysis adjusted for traditional risk factors, and CT-measured visceral adipose tissue area in a subgroup of subjects showed that the increased CAC scores were significantly associated with the presence of NAFLD (OR 1.28, 95% CI 1.04-1.59, P=0.023) independent of visceral adiposity. CONCLUSIONS Patients with NAFLD are at increased risk for coronary atherosclerosis independent of classical coronary risk factors, including visceral adiposity. These data suggest that NAFLD per se might be an independent risk factor for coronary artery disease.

Incidence of NAFLD diagnosis in the community has increased 5-fold, particularly in young adults. NAFLD is a consequence, but also a precursor of MC. Incident MC attenuates the impact of NAFLD on death and annuls its impact on CV disease. (Hepatology 2018;67:1726-1736).