Albuminuria, estimated glomerular filtration rate, and traditional predictors for composite cardiovascular and kidney outcome: a population-based cohort study in Korea

Machine learning approaches toward an understanding of acute kidney injury: current trends and future directions

Acute kidney injury (AKI) is a significant health challenge associated with adverse patient outcomes and substantial economic burdens. Many authors have sought to prevent and predict AKI. Here, we comprehensively review recent advances in the use of artificial intelligence (AI) to predict AKI, and the associated challenges. Although AI may detect AKI early and predict prognosis, integration of AI-based systems into clinical practice remains challenging. It is difficult to identify AKI patients using retrospective data; information preprocessing and the limitations of existing models pose problems. It is essential to embrace standardized labeling criteria and to form international multi-institutional collaborations that foster high-quality data collection. Additionally, existing constraints on the deployment of evolving AI technologies in real-world healthcare settings and enhancement of the reliabilities of AI outputs are crucial. Such efforts will improve the clinical applicability, performance, and reliability of AKI Clinical Support Systems, ultimately enhancing patient prognoses.

Association between dietary magnesium intake and incident chronic kidney disease: a prospective observational cohort study

BACKGROUND

Although serum magnesium deficiency is linked to higher cardiovascular disease risk, its association with chronic kidney disease (CKD) remains unclear.

OBJECTIVES

This study aimed to evaluate the relationship between dietary magnesium intake and CKD development in adults with clinically normal kidney function.

METHODS

The prospective observational cohort study evaluated 188,510 participants (median age, 57.0 y; female, 54.1%) from the UK Biobank. Dietary magnesium intake was assessed through a 24-h dietary recall questionnaire compromising a list of 206 foods and 32 beverages and categorized into quintiles. The primary outcome was incident CKD diagnosed through International Classification of Diseases-10 and Office of Population Censuses and Surveys 4 codes. Incident CKD, defined as estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2, was also assessed in a subcohort with creatinine follow-up data.

RESULTS

The median magnesium intake amount per person was 323.2 mg/d [interquartile range (IQR): 269.4-382.7 mg/d]. During 1,826,038.1 person-years of follow-up (median: 9.6 y; IQR: 9.3-10.3 y), CKD developed in 5,878 participants. The incidence of CKD was progressively higher in participants with lower magnesium intake (2.8%, 2.8%, 3.0%, 3.2%, and 3.7% in Q5-Q1, respectively). Cox regression analysis revealed that the hazard ratios (HRs) for incident CKD increased in a stepwise manner toward lower magnesium intake quintiles {adjusted HR (95% confidence interval [CI])-Q4: 0.97 (0.89, 1.06); Q3: 1.05 (0.96, 1.14); Q2: 1.12 (1.03, 1.21); Q1: 1.30 (1.20, 1.41)} relative to Q5 (P-linearity < 0.001). Similar results were observed with eGFR-defined CKD outcome [adjusted HR (95% CI)-Q4: 1.09 (0.92, 1.28); Q3: 1.15 (0.98, 1.35); Q2: 1.21 (1.03, 1.42); Q1: 1.41 (1.20, 1.65) relative to Q5; P-linearity < 0.001].

CONCLUSIONS

Lower dietary magnesium intake was associated with higher risk of incident CKD in adults with clinically normal kidney function. Further controlled studies are required to establish the potential benefit of adequate magnesium intake.

Association between progression of coronary artery calcification and development of kidney failure with replacement therapy: Findings from KNOW-CKD study

BACKGROUND AND AIMS

High coronary artery calcification (CAC) burden is a significant risk factor for adverse cardiovascular and kidney outcomes. However, it is unknown whether changes in the coronary atherosclerotic burden can accompany changes in kidney disease progression. Here, we evaluated the relationship between CAC progression and the risk of kidney failure with replacement therapy (KFRT).

METHODS

We analyzed 1173 participants with chronic kidney disease (CKD) G1 to G5 without kidney replacement therapy from the KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD). Participants were categorized into three groups according to the change in the CAC score between enrollment and year 4 (non-progressors, ≤0 AU; moderate progressors, 1-199 AU; and severe progressors, ≥200 AU). The primary outcome was the development of KFRT.

RESULTS

During a follow-up period of 4690 person-years (median, 4.2 years), the primary outcome occurred in 230 (19.6 %) participants. The incidence of KFRT was 37.6, 54.3, and 80.9 per 1000 person-years in the non-, moderate, and severe progressors, respectively. In the multivariable cause-specific hazard model, the hazard ratios (HRs) for the moderate and severe progressors were 1.71 (95 % confidence interval [CI], 1.02-2.87) and 2.55 (95 % CI, 1.07-6.06), respectively, compared with non-progressors. A different definition of CAC progression with a threshold of 100 AU yielded similar results in a sensitivity analysis.

CONCLUSIONS

CAC progression is associated with an increased risk of KFRT in patients with CKD. Our findings suggest that coronary atherosclerosis changes increase the risk of CKD progression.

Association of 1,25 dihydroxyvitamin D with left ventricular hypertrophy and left ventricular diastolic dysfunction in patients with chronic kidney disease

Left ventricular hypertrophy (LVH) and left ventricular diastolic dysfunction (LVDD) are highly prevalent predictors of cardiovascular disease in individuals with chronic kidney disease (CKD). Vitamin D, particularly 25-hydroxyvitamin D [25(OH)D], deficiency has been reported to be associated with cardiac structure and function in CKD patients. In the current study, we investigated the association between 1,25-dihydroxyvitamin D [1,25(OH)2D], the active form of 25(OH)D, and LVH/LVDD in CKD patients. We enrolled 513 non-dialysis CKD patients. The presence of LVH and LVDD was determined using transthoracic echocardiography. In multivariable analysis, serum 1,25(OH)2D levels, but not serum 25(OH)D, were independently associated with LVH [odds ratio (OR): 0.90, 95% confidential interval (CI): 0.88-0.93, P < 0.001]. Additionally, age, systolic blood pressure, and intact parathyroid hormone levels were independently associated with LVH. Similarly, multivariable analysis demonstrated that serum 1,25(OH)2D levels, but not 25(OH)D levels, were independently associated with LVDD (OR: 0.88, 95% CI: 0.86-0.91, P < 0.001) with systolic blood pressure showing independent association with LVDD. The optimal cut-off values for serum 1,25(OH)2D levels for identifying LVH and LVDD were determined as ≤ 12.7 pg/dl and ≤ 18.1 pg/dl, respectively. Our findings suggest that serum 1,25(OH)2D levels have independent association with LVH and LVDD in CKD patients, underscoring their potential as biomarkers for these conditions in this patient population.

Association between Relative Thrombocytosis and Microalbuminuria in Adults with Mild Fasting Hyperglycemia

An elevated platelet count may contribute to significant thrombotic events and pose a risk for diabetic microvascular complications. Albuminuria, one of the hallmarks of diabetes, is thought to be a risk factor for endothelial dysfunction. In this study, we investigated the association between relative thrombocytosis and an increased urine albumin-to-creatinine ratio in healthy adult participants. Using multivariate analyses on data from the Korea National Health and Nutrition Examination Survey V-VI, 12,525 eligible native Koreans aged ≥ 20 were categorized into platelet count quintiles by sex. The highest platelet count quintile included younger, more obese participants with elevated white blood cell counts, poor lipid profiles, and a better estimated glomerular filtration rate. Restricted cubic spline regression analysis revealed significant associations between platelet count and fasting blood glucose, glycated hemoglobin, and urine albumin-to-creatinine ratio. Adjusted logistic regression models indicated that heightened fasting blood glucose and platelet count were linked to risk of microalbuminuria (fasting blood glucose, odds ratio = 1.026, 95%CI = 1.011-1.042; platelet count, odds ratio = 1.004, 95%CI = 1.002-1.006). Particularly, an increased platelet count was notably associated with microalbuminuria progression in subjects with impaired fasting glucose. These findings suggest that an elevated platelet count, even below diagnostic thrombocytosis levels, independently correlates with an increased risk of vascular endothelial dysfunction in patients with impaired fasting glucose.

Nocturnal systolic blood pressure dipping and progression of chronic kidney disease

The relationship between declining nocturnal blood pressure (BP) and adverse cardiovascular outcomes is well-recognized. However, the relationship between diurnal BP profile and the risk of chronic kidney disease (CKD) progression is unclear. Herein, we examined the association between nocturnal systolic SBP (SBP) dipping and CKD progression in 1061 participants at the Cardiovascular and Metabolic Disease Etiology Research Center-High Risk (CMERC-HI). The main exposure was diurnal systolic BP (SBP) profile and diurnal SBP difference ([nighttime SBP-daytime SBP] × 100/daytime SBP). The primary outcome was CKD progression, defined as a composite of ≥ a 50% decline in the estimated glomerular filtration rate from baseline or the initiation of kidney replacement therapy. During 4749 person-years of follow-up (median, 4.8 years), the composite outcome occurred in 380 (35.8%) participants. Compared to dippers, the hazard ratios (HRs) for the risk of adverse kidney outcomes were 1.02 (95% confidence interval [CI], 0.64-1.62), 1.30 (95% CI, 1.02-1.66), and 1.40 (95% CI, 1.03-1.90) for extreme dipper, non-dipper, and reverse dipper, respectively. In a continuous modeling, a 10% increase in diurnal SBP difference was associated with a 1.21-fold (95% CI, 1.07-1.37) higher risk of CKD progression. Thus, decreased nocturnal SBP decline was associated with adverse kidney outcomes in patients with CKD. Particularly, patients with non-dipping and reverse dipping patterns were at higher risk for CKD progression than those with a dipping pattern.