Estimating renal function in old people: an in-depth review

Chronic kidney disease in geriatric patients: Estimating glomerular filtration rate in older patients with comorbidities

Aging is an inevitable process that is usually measured by chronological age, with people aged 65 and over being defined as "older individuals". There is disagreement in the current scientific literature regarding the best methods to estimate glomerular filtration rate (eGFR) in older adults. Several studies suggest the use of an age-adjusted definition to improve accuracy and avoid overdiagnosis. In contrast, some researchers argue that such changes could complicate the classification of chronic kidney disease (CKD). Several formulas, including the Modification of Diet in Renal Disease, CKD-Epidemiology Collaboration, and Cockcroft-Gault equations, are used to estimate eGFR. However, each of these formulas has significant limitations when applied to older adults, primarily due to sarcopenia and malnutrition, which greatly affect both muscle mass and creatinine levels. Alternative formulas, such as the Berlin Initiative Study and the Full Age Spectrum equations, provide more accurate estimates of values for older adults by accounting for age-related physiological changes. In frail older adults, the use of cystatin C leads to better eGFR calculations to assess renal function. Accurate eGFR measurements improve the health of older patients by enabling better medication dosing. A thorough approach that includes multiple calibrated diagnostic methods and a detailed geriatric assessment is necessary for the effective management of kidney disease and other age-related conditions in older adults.

Pharmacokinetic and pharmacodynamic alterations in older people: what we know so far

INTRODUCTION

Healthcare professionals face increasing challenges when managing older patients, a group characterized by significant interindividual variability in comorbidity patterns, homeostatic capacity, frailty status, cognitive function, and life expectancy. Complex therapeutic decisions may increase the risk of inappropriate polypharmacy, drug-drug, and drug-disease interactions in the context of age-associated pharmacokinetic and pharmacodynamic alterations, with consequent drug accumulation and toxicity.

AREAS COVERED

This state-of-the-art narrative review article summarizes and critically appraises the results of original research studies and reviews published in PubMed, Scopus, and Web of Science, from inception to 9 April 2025, on age-associated changes in critical organs and systems and relevant pharmacokinetic and pharmacodynamic alterations. It also discusses the emerging role of frailty and the gut microbiota in influencing such alterations and the potential utility of machine learning techniques in identifying new signals of drug efficacy and toxicity in older patients.

EXPERT OPINION

The available knowledge regarding specific age-associated pharmacokinetic and pharmacodynamic alterations applies to a limited number of drugs, some of which are not frequently prescribed in contemporary practice. Future studies investigating a wider range of drugs and their patterns of use will likely enhance therapeutic efficacy and minimize toxicity in the older patient population.

Anemia in Elderly Patients: Contribution of Renal Aging and Chronic Kidney Disease

Renal aging is a physiological process characterized by structural and functional changes in the kidneys. The presence of disorders or pathologies can exacerbate these age-related changes, potentially leading to organ dysfunction. Chronic kidney disease (CKD), a significant global public health issue, is particularly prevalent in the elderly and is often associated with the age-related decline in kidney function. Anemia is one of the most frequent complications of CKD and is also highly prevalent in the elderly. Mild anemia, often multifactorial, is the most common presentation. Understanding the mechanisms driving anemia in this population is crucial to ensure appropriate treatment. The primary etiologies include nutritional deficiency, anemia of unknown cause, and anemia of chronic diseases, including CKD. This review provides an in-depth exploration of the complex pathophysiological mechanisms underlying anemia in elderly patients with CKD.

Hypocalcemia Event Associated with Denosumab: A Real-World Study from FDA Adverse Event Reporting System (FAERS) Database

BACKGROUND AND OBJECTIVE

Denosumab is widely used for osteoporosis and cancer treatment. However, hypocalcemia induced by denosumab is a frequent adverse event. The objective of this study is to comprehensively investigate the safety signals and the occurrence of hypocalcemia in real-world patient cases reported through the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS).

METHODS

Reports from January 1, 2017 to December 31, 2021 were extracted from the FAERS. Only cases of hypocalcemia suspected to denosumab were eligible in pharmacovigilance study. Denosumab-related hypocalcemia safety signal were identified to characterize their clinical features. A safety signal for hypocalcemia was evaluated using reporting odds ratios (ROR).

RESULTS

Among the 102,413 cases related to denosumab, 1042 cases were reported with denosumab-related hypocalcemia. The affected patients were mainly elderly (median age 70 years) and male (n = 568, 63.5%). In available data, the median onset time of 23 (range 0-1601) days. Most patients required drug interruption (n = 226, 72.9%) and can achieve a recovered-resolved state (n = 318, 62.1%). For the whole database, denosumab exhibited a safety signal for hypocalcemia (ROR = 14.09, 95% Cl 13.18, 15.06). In the sensitivity analyses, denosumab also showed a safety signal for hypocalcemia in cancer (ROR = 21.28, 95% Cl 18.79, 24.11) and osteoporosis (ROR = 9.29, 95% Cl 6.80, 12.59). Compared with bisphosphonates, denosumab still has safety signal for hypocalcemia (ROR = 1.88, 95% Cl 1.67, 2.11).

CONCLUSIONS

This pharmacovigilance database analysis indicates a high safety signal for hypocalcemia associated with denosumab, particularly in cancer patients.

Growth Performance, Dietary Energetics, Blood Metabolites, Carcass Traits, Meat Quality, and Gene Expression of Lambs Supplemented with a Polyherbal Phytogenic Additive

This study aimed to evaluate the effects of supplementation with a polyherbal phytogenic additive (PPA) on the productive performance, dietary energetics, blood metabolites, carcass traits, meat quality, and gene expression of finishing lambs. Thirty-six male Pelibuey lambs (23.61 ± 0.57 kg body weight (BW)) were housed in individual pens and assigned to four treatments (n = 9) with different doses of PPA: 0 (CON), 2.5 (PPAL), 5 (PPAM), and 7.5 (PPAH) g of PPA/kg of DM for 56 days. Average daily gain, dry matter intake, and observed dietary net energy for maintenance and weight gain increased linearly (p < 0.05) in lambs supplemented with PPAH. A linear reduction (p = 0.02) in FCR was detected in lambs fed PPAM and PPAH. The PPAH supplementation linearly increased (p < 0.001) Longissimus dorsi muscle area, but other carcass traits were not affected (p > 0.05) by PPA doses. The physicochemical characteristics of the meat and the hematological parameters of the lambs were not affected (p > 0.05) by the PPA doses. The glucose, uric acid, creatinine, and bilirubin serum concentrations decreased linearly (p < 0.05) in lambs supplemented with PPAM and PPAH. Gene ontology analyses showed that nine biological processes were modified (p < 0.05), including DNA replication, drug metabolism-cytochrome P450, oxidative phosphorylation, and chemical carcinogenesis-reactive oxygen species. In conclusion, high doses (7.5 g/kg DM) of PPA can improve growth performance and dietary energy utilization efficiency in finishing lambs. Likewise, gene expression analysis indicates that supplementation with high doses of PPA could improve energy production and antioxidant status in finishing lambs.

SDMA as a marker and mediator in cerebrovascular disease

Symmetric dimethylarginine (SDMA) is a methylated derivative of arginine, generated by all cells as a by-product of cellular metabolism and eliminated via the kidney. For many years SDMA has been considered inert and of little biological significance. However, a growing body of evidence now suggests this view is outdated and that circulating SDMA levels may, in fact, be intricately linked to endothelial dysfunction and vascular risk. In this review, we specifically examine SDMA within the context of cerebrovascular disease, with a particular focus on ischaemic stroke. We first discuss pre-clinical evidence supporting the notion that SDMA has effects on nitric oxide signalling, inflammation, oxidative stress, and HDL function. We then appraise the most recent clinical studies that explore the relationship between circulating SDMA and cerebrovascular risk factors, such as chronic kidney disease, hypertension, atrial fibrillation, and atherosclerosis, exploring whether any associations may arise due to the existence of shared risk factors. Finally, we consider the evidence that elevated circulating SDMA is linked to poor outcomes following ischaemic and haemorrhagic stroke. We draw upon pre-clinical insights into SDMA function to speculate how SDMA may not only be a marker of cerebrovascular disease but could also directly influence cerebrovascular pathology, and we highlight the pressing need for more mechanistic pre-clinical studies alongside adequately powered, longitudinal clinical studies to fully evaluate SDMA as a marker/mediator of disease.

Population-based reference values for kidney function and kidney function decline in 25- to 95-year-old Germans without and with diabetes

Understanding normal aging of kidney function is pivotal to help distinguish individuals at particular risk for chronic kidney disease. Glomerular filtration rate (GFR) is typically estimated via serum creatinine (eGFRcrea) or cystatin C (eGFRcys). Since population-based age-group-specific reference values for eGFR and eGFR-decline are scarce, we aimed to provide such reference values from population-based data of a wide age range. In four German population-based cohorts (KORA-3, KORA-4, AugUR, DIACORE), participants underwent medical exams, interview, and blood draw up to five times within up to 25 years. We analyzed eGFRcrea and eGFRcys cross-sectionally and longitudinally (12,000 individuals, age 25-95 years). Cross-sectionally, we found age-group-specific eGFRcrea to decrease approximately linearly across the full age range, for eGFRcys up to the age of 60 years. Within age-groups, there was little difference by sex or diabetes status. Longitudinally, linear mixed models estimated an annual eGFRcrea decline of -0.80 [95% confidence interval -0.82, -0.77], -0.79 [-0.83, -0.76], and -1.20 mL/min/1.73m2 [-1.33, -1.08] for the general population, "healthy" individuals, or individuals with diabetes, respectively. Reference values for eGFR using cross-sectional data were shown as percentile curves for "healthy" individuals and for individuals with diabetes. Reference values for eGFR-decline using longitudinal data were presented as 95% prediction intervals for "healthy" individuals and for individuals with diabetes, obesity, and/or albuminuria. Thus, our results can help clinicians to judge eGFR values in individuals seen in clinical practice according to their age and to understand the expected range of annual eGFR-decline based on their risk profile.

Association of serum cystatin C level and major adverse cardiovascular events in patients with percutaneous coronary intervention

Background

Recurrent acute myocardial infarction requiring unplanned percutaneous coronary intervention (PCI) is one of the major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS) after PCI. There is a continuing controversy about the association between serum cystatin C, a biomarker for the evaluation of renal function, and the prognosis of ACS patients following PCI. The retrospective study evaluated the association between serum cystatin C level and MACE in ACS patients after PCI.

Methods

Data were retrieved for 330 patients with ACS for primary PCI in a single center. Serum cystatin C levels were measured before PCI. All patients underwent regular follow-ups after PCI, and the studied endpoint was MACE, defined as the need for a repeat revascularization in the heart. The predictive value of serum cystatin C for MACE was analyzed using univariate and multivariate analysis. Restricted cubic spline (RCS) analysis was applied to evaluate the dose-response relationship between serum cystatin C level and MACE in ACS patients following PCI.

Results

After a median follow-up of 63 months (range, 1-148 months), 121 of the 330 patients experienced MACE. Compared to patients who did not have MACE, patients who had MACE showed a significant decrease in serum cystatin C levels (0.99±0.32 vs. 1.15±0.78 mg/L, P=0.03). In multivariate regression analysis, serum cystatin C level was an independent risk factor for MACE. According to the serum cystatin C level, patients were divided into 4 categories, Cox regression analysis illustrated that the second quartile of serum cystatin C level indicated an increased risk of MACE in patients with PCI for primary ACS compared to the highest quartile [Q2: adjusted hazard ratio (HR) =2.109; 95% confidence interval (CI): 1.193-3.727; P=0.01]. RCS analysis showed a significant U-shaped dose-response relationship between cystatin C level and MACE in patients with PCI for ACS (P for non-linearity =0.004).

Conclusions

These results indicated an association between serum cystatin C level and post-PCI MACE in ACS patients.

Protein Intake and Mortality in Older Adults With Chronic Kidney Disease

Importance

Avoiding high protein intake in older adults with chronic kidney disease (CKD) may reduce the risk of kidney function decline, but whether it can be suboptimal for survival is not well known.

Objective

To estimate the associations of total, animal, and plant protein intake with all-cause mortality in older adults with mild or moderate CKD and compare the results to those of older persons without CKD.

Design, Setting, and Participants

Data from 3 cohorts (Study on Cardiovascular Health, Nutrition and Frailty in Older Adults in Spain 1 and 2 and the Swedish National Study on Aging and Care in Kungsholmen [in Sweden]) composed of community-dwelling adults 60 years or older were used. Participants were recruited between March 2001 and June 2017 and followed up for mortality from December 2021 to January 2024. Those with no information on diet or mortality, with CKD stages 4 or 5, or undergoing kidney replacement therapy and kidney transplant recipients were excluded. Data were originally analyzed from June 2023 to February 2024 and reanalyzed in May 2024.

Exposures

Cumulative protein intake, estimated via validated dietary histories and food frequency questionnaires.

Main Outcomes and Measures

The study outcome was 10-year all-cause mortality, ascertained with national death registers. Chronic kidney disease was ascertained according to estimated glomerular filtration rates, urine albumin excretion, and diagnoses from medical records.

Results

The study sample consisted of 8543 participants and 14 399 observations. Of the 4789 observations with CKD stages 1 to 3, 2726 (56.9%) corresponded to female sex, and mean (SD) age was 78.0 (7.2) years. During the follow-up period, 1468 deaths were recorded. Higher total protein intake was associated with lower mortality among participants with CKD; adjusted hazard ratio (HR) for 1.00 vs 0.80 g/kg/d was 0.88 (95% CI, 0.79-0.98); for 1.20 vs 0.80 g/kg/d, 0.79 (95% CI, 0.66-0.95); and for 1.40 vs 0.80 g/kg/d, 0.73 (95% CI, 0.57-0.92). Associations with mortality were comparable for plant and animal protein (HRs, 0.80 [95% CI, 0.65-0.98] and 0.88 [95% CI, 0.81-0.95] per 0.20-g/kg/d increment, respectively) and for total protein intake in participants younger than 75 years vs 75 years or older (HRs, 0.94 [95% CI, 0.85-1.04] and 0.91 [95% CI, 0.85-0.98] per 0.20-g/kg/d increment in total protein intake, respectively). However, the hazards were lower among participants without CKD than in those with CKD (HRs, 0.85 [95% CI, 0.79-0.92] and 0.92 [95% CI, 0.86-0.98] per 0.20-g/kg/d increment, respectively; P = .02 for interaction).

Conclusions and Relevance

In this multicohort study of older adults, higher intake of total, animal, and plant protein was associated with lower mortality in participants with CKD. Associations were stronger in those without CKD, suggesting that the benefits of proteins may outweigh the downsides in older adults with mild or moderate CKD.

Biomarkers of chronic kidney disease in older individuals: navigating complexity in diagnosis

Chronic kidney disease (CKD) in older individuals is a matter of growing concern in the field of public health across the globe. Indeed, prevalence of kidney function impairment increases with advancing age and is often exacerbated by age-induced modifications of kidney function, presence of chronic diseases such as diabetes, hypertension, and cardiovascular disorders, and increased burden related to frailty, cognitive impairment and sarcopenia. Accurate assessment of CKD in older individuals is crucial for timely intervention and management and relies heavily on biomarkers for disease diagnosis and monitoring. However, the interpretation of these biomarkers in older patients may be complex due to interplays between CKD, aging, chronic diseases and geriatric syndromes. Biomarkers such as serum creatinine, estimated glomerular filtration rate (eGFR), and albuminuria can be significantly altered by systemic inflammation, metabolic changes, and medication use commonly seen in this population. To overcome the limitations of traditional biomarkers, several innovative proteins have been investigated as potential, in this review we aimed at consolidating the existing data concerning the geriatric aspects of CKD, describing the challenges and considerations in using traditional and innovative biomarkers to assess CKD in older patients, highlighting the need for integration of the clinical context to improve biomarkers' accuracy.

Age and estimated glomerular filtration rate in Chinese older adults: a cohort study from 2014 to 2020

Objectives

This study aimed to fill the data gap of the course of renal function decline in old age and explore changes in renal function across different health states with increasing age.

Methods

This observational, retrospective, single-center cohort study included 5,112 Chinese older adults (3,321 men and 1,791 women, range 60-104 years). The individual rate of estimated glomerular filtration rate (eGFR) decline was analyzed using linear mixed-effects model to account for repeated measures over the years.

Results

The median age was 66 years, median BMI was 24.56 kg/m2, and median eGFR was 89.86 mL/min.1.73 m2. For every 1-year increase in age, women's eGFR decreased by 1.06 mL/min/1.73 m2 and men's by 0.91 mL/min/1.73 m2. We observed greater age-related eGFR decline in men and women with high systolic blood pressure (SBP). Men with high triglyceride (TG), high low-density lipoprotein cholesterol (LDL-C), and low high-density lipoprotein cholesterol (HDL-C), had greater age-related eGFR decline. In women, different BMI groups showed significant differences in age-related eGFR decline, with the highest decline in those with obesity. Additionally, participants with normal baseline eGFR had a faster age-related decline than those with low baseline eGFR.

Conclusion

The eGFR declined linearly with age in Chinese older adults, with women exhibiting a slightly faster decline than men. Both men and women should be cautious of SBP. Older adults with normal baseline renal function experienced a faster eGFR decline. Men with high TG, LDL-C, and low HDL-C levels, as well as obese women, should be vigilant in monitoring renal function.

Objective assessment of the association between telomere length, a biomarker of aging, and health screening indicators: A cross-sectional study

Physical examination data are used to indicate individual health status and organ health, and understanding which physical examination data are indicative of physiological aging is critical for health management and early intervention. There is a lack of research on physical examination data and telomere length. Therefore, the present study analyzed the association between blood telomere length and physical examination indices in healthy people of different ages to investigate the role and association of various organs/systems with physiological aging in the human body. The present study was a cross-sectional study. Sixteen physical examination indicators of different tissue and organ health status were selected and analyzed for trends in relation to actual age and telomere length (TL). The study included 632 individuals with a total of 11,766 data for 16 physical examination indicators. Age was linearly correlated with 11 indicators. Interestingly, telomere length was strongly correlated only with the renal indicators eGFR (P < .001), CYS-C (P < .001), and SCR (P < .001). The study established that renal aging or injury is a risk factor for Physical aging of the human body. Early identification and management are essential to healthcare.

Discrepancies among equations to estimate the glomerular filtration rate for drug dosing decision making in aged patients: a cross sectional study

BACKGROUND

Patients often require adjustments to drug doses due to impaired renal function. Glomerular filtration rate (GFR) estimation using various equations can result in discrepancies, potentially leading to different dose adjustment recommendations.

AIM

To determine the clinical significance of discrepancies observed between different equations used to estimate GFR for drug dose adjustments in a real-world group of patients over 65 years in primary care.

METHOD

The Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Berlin Initiative Study 1 equations were applied to estimate GFR in a group of patients over 65 years old attending a primary care center. Results were compared using Bland-Altman plots, and limits of agreement (LoA) and overall bias were calculated. Regression analyses were conducted to identify the null difference GFR and the slope of differences for each pairwise comparison.

RESULTS

A total of 1886 patients were analyzed. Differences between patient-adjusted and body surface area (BSA)-normalized versions of the equations were not clinically relevant for dose adjustments, with LoAs below 20 mL/min. However, discrepancies among the original versions of several equations presented LoAs over 30 mL/min. Greater differences were found between CG and MDRD or CKD-EPI equations.

CONCLUSION

Clinically relevant differences in GFR estimation were observed among different equations, potentially impacting drug dose adjustments. However, discrepancies were not considered significant when comparing patient-adjusted and BSA-normalized versions of the equations, particularly for patients with BSA close to the average.

Estimating Muscle Mass Using D3-Creatine Dilution: A Narrative Review of Clinical Implications and Comparison With Other Methods

BACKGROUND

The D3-creatine (D3-Cr) dilution method is of emerging interest for estimating total-body skeletal muscle mass. This review explores the association of muscle mass estimated via D3-Cr with various clinical outcomes and provides a summary of the literature comparing D3-Cr with other body composition techniques.

METHODS

A literature search was conducted on PubMed/MEDLINE and Web of Science for studies using D3-Cr to measure muscle in adult populations (ie, ≥18 years old) from inception until September 2023.

RESULTS

Out of the 23 included studies, 15 investigated the correlation between D3-Cr and clinical outcomes. More consistent associations were reported for mortality (100%, n = 2), mobility disability (100%; n = 5), falls and fractures (100%; n = 3), physical performance (63.3%; n = 11), muscle strength (44.4%; n = 9), and muscle composition (33.3%; n = 3). However, conflicting findings were also reported for such correlations. Among the 23 studies, 14 compared D3-Cr-estimated muscle with other body composition techniques, including magnetic resonance imaging (MRI) as a reference method. Strong and positive correlations were found between D3-Cr and MRI. Nonetheless, variations in muscle measurements were noted, with differences in D3-Cr values ranging from 0.62 kg lower to 13.47 kg higher compared to MRI.

CONCLUSIONS

D3-Cr-estimated muscle mass may be a valuable predictor of clinical outcomes showing consistent associations with falls and fractures, mobility disability, and mortality. However, less consistent associations were found with muscle strength and composition, and physical performance. Although a strong correlation exists between D3-Cr-estimated muscle mass and MRI measurements, under- or overestimation may occur.

Differential Impact of the UNOS Simultaneous Liver-kidney Transplant Policy Change Among Patients With Sustained Acute Kidney Injury

BACKGROUND

Simultaneous liver-kidney transplant (SLK) allocation policy in the United States was revised in August 2017, reducing access for liver transplant candidates with sustained acute kidney injury (sAKI) and potentially adversely impacting vulnerable populations whose true renal function is overestimated by commonly used estimation equations.

METHODS

We examined national transplant registry data containing information for all liver transplant recipients from June 2013 to December 2021 to assess the impact of this policy change using instrumental variable estimation based on date of listing.

RESULTS

Posttransplant survival was compared for propensity-matched patients with sAKI who were only eligible for liver transplant alone (LTA_post; n = 638) after the policy change but would have been SLK-eligible before August 2017, with similar patients who were previously able to receive an SLK (SLK; n = 319). Overall posttransplant patient survival was similar at 3 y (81% versus 80%; P = 0.9). However, receiving an SLK versus LTA increased survival among African Americans (87% versus 61% at 3 y; P = 0.029). A trend toward survival benefit from SLK versus LTA, especially later in the follow-up period, was observed in recipients ≥ age 60 (3-y survival: 84% versus 76%; P = 0.2) and women (86% versus 80%; P = 0.2).

CONCLUSIONS

The 2017 United Network for Organ Sharing SLK Allocation Policy was associated with reduced survival of African Americans with end-stage liver disease and sAKI and, potentially, older patients and women. Our study suggested the use of race-neutral estimation of renal function would ameliorate racial disparities in the SLK arena; however, further studies are needed to reduce disparity in posttransplant outcomes among patients with liver and kidney failure.

Deprescribing in Older Poly-Treated Patients Affected with Dementia

Polypharmacy is an important issue in older patients affected by dementia because they are very vulnerable to the side effects of drugs'. Between October 2021 and September 2022, we randomly assessed 205 old-aged outpatients. The study was carried out in a Center for Dementia in collaboration with a university center. The primary outcomes were: (1) deprescribing inappropriate drugs through the Beers and STOPP&START criteria; (2) assessing duplicate drugs and the risk of iatrogenic damage due to drug-drug and drug-disease interactions. Overall, 69 men and 136 women (mean age 82.7 ± 7.4 years) were assessed. Of these, 91 patients were home care patients and 114 were outpatient. The average number of the drugs used in the sample was 9.4 drugs per patient; after the first visit and the consequent deprescribing process, the average dropped to 8.7 drugs per patient (p = 0.04). Overall, 74 potentially inappropriate drugs were used (36.1%). Of these, long half-life benzodiazepines (8.8%), non-steroidal anti-inflammatory drugs (3.4%), tricyclic antidepressants (3.4%), first-generation antihistamines (1.4%), anticholinergics (11.7%), antiplatelet drugs (i.e., ticlopidine) (1.4%), prokinetics in chronic use (1.4%), digoxin (>0.125 mg/day) (1.4%), antiarrhythmics (i.e., amiodarone) (0.97%), and α-blockers (1.9%) were included. The so-called "duplicate" drugs were overall 26 (12.7%). In total, ten potentially dangerous prescriptions were found for possible interactions (4.8%). We underline the importance of checking all the drugs taken periodically and discontinuing drugs with the lowest benefit-to-harm ratio and the lowest probability of adverse reactions due to withdrawal. Computer tools and adequately trained teams (doctors, nurses, and pharmacists) could identify, treat, and prevent possible drug interactions.

Added value of non-contrast CT for the diagnosis of acute pyelonephritis in older patients with suspected infection with an unknown focus: a retrospective diagnostic study

OBJECTIVES

In older patients, the diagnosis of acute pyelonephritis (APN) is challenging. The aim was to evaluate the added value of CT to history, physical examination and urinalysis for the diagnosis of APN in older patients with suspected infection with an unknown focus.

DESIGN

Retrospective diagnostic study.

SETTING

Department of General Medicine in an acute care hospital in Japan.

PARTICIPANTS

Patients aged ≥65 years who underwent blood cultures, a urine culture, and chest and abdominal CT to detect the focus of infection were included.

PRIMARY OUTCOME MEASURES

Two radiologists independently reviewed four non-contrast CT signs: perirenal fat stranding, pelvicalyceal wall thickening, enlargement of the kidney and thickening of Gerota's fascia. Findings on contrast-enhanced CT could not be evaluated due to an insufficient number of patients in whom contrast-enhanced CT was performed. An expert panel was used as the reference standard for APN. The added value of CT findings was quantified by comparing the diagnostic performance between a model based on 10 predictors available before CT and an extended model including the CT findings.

RESULTS

Of 473 patients, 61 (14.8%) were diagnosed with APN. When the laterality of the CT findings was taken into account, the model fit was not improved by adding them. In the laterality-insensitive analysis, the model performance was significantly improved by adding the CT signs (likelihood-ratio test p=0.03; c-index 0.89 vs 0.91, p=0.03). However, their clinical utility was only to improve the classification of 11.5% of patients with APN.

CONCLUSIONS

The added value of non-contrast CT findings to history, physical examination and urinalysis was limited for the diagnosis of APN in older patients with a suspected infection with an unknown focus.

Questionable Validity of Creatinine-Based eGFR in Elderly Patients but Cystatin C Is Helpful in First-Line Diagnostics

BACKGROUND

The recommended chronic kidney disease (CKD) first-line diagnostic test is based on the creatinine-derived (estimated) glomerular filtration rate (eGFR). Cystatin C use may provide a better assessment.

METHODS

We compared creatinine- and cystatin C-derived eGFR determination as the first-line diagnostic test for 112 hospital patients aged > 60 years (median = 76 years). The patients were judged to not have CKD (no-CKD group) according to the first-line diagnostic recommendations (n = 61, eGFR (CKD Epidemiology Collaboration (CKD-EPI)) ≥ 60 mL/min/1.73 m2, total urine protein < 150 mg/g creatinine, urinary red/white blood cells not increased) or classified to be at risk for kidney insufficiency due to aortic valve dysfunction (at-risk group; n = 51). The accuracy of the eGFR values was evaluated retrospectively with the final case diagnoses.

RESULTS

The eGFR (Caucasian, Asian, pediatric, and adult formula (CAPA)) was found to be linearly correlated to the eGFR (CKD-EPI) (R2 = 0.5, slope = 0.69, p < 0.0001). In 93/112 (>80%) cases, the eGFR (CAPA) yielded lower values (on average ≈-20%). In 55/112 (49%) cases, the cystatin C-derived CKD stage was lower. CKD reclassification from no-CKD to a kidney-insufficient state (i.e., CKD1/2 to CKD3a/b or 4) or reclassification to a more severe kidney insufficiency (i.e., CKD3a → 3b/4 or 3b → 4) was found in 41/112 (37%) cases. A worse CKD classification (no-CKD → kidney-insufficient) based on the eGFR (CAPA) was plausible in 30% of cases in light of the final case diagnoses.

CONCLUSION

In elderly patients (>60 years), renal function appears to be systematically overestimated by the creatinine-based eGFR (CKD-EPI), indicating that, for this group, the cystatin C-based eGFR (CAPA) should be used as the first-line diagnostic test.

Longitudinal profiling and tracking stability in the Singapore study of macro-angiopathy and microvascular reactivity in type 2 diabetes cohort

INTRODUCTION

The Singapore Study of Macro-Angiopathy and microvascular Reactivity in Type 2 Diabetes (SMART2D) is a prospective cohort study which was started in 2011 to investigate the effect of risk factors on vascular function and diabetes-related complications in Asians. We aimed to compare the longitudinal change in risk factors by accounting for batch effect and assess the tracking stability of risk factors over time in patients recruited for SMART2D. In this study, we (1) described batch effect and its extent across a heterogenous range of longitudinal data parameters; (2) mitigated batch effect through statistical approach; and (3) assessed the tracking stability of the risk factors over time.

METHODS

A total of 2258 patients with type 2 diabetes mellitus (T2DM) were recruited at baseline. The study adopted a three-wave longitudinal design with intervals of 3 years between consecutive waves. The changes in a few selected risk factors were assessed after calibration, assuming patients with similar demographic and anthropometry profile had similar physiology. The tracking pattern of the risk factors was determined with stability coefficients derived from generalised estimating equations.

RESULTS

The medians of the longitudinal differences in risk factors between the waves were mostly modest at <10%. Larger increases in augmentation index (AI), aortic systolic blood pressure (BP) and aortic mean BP were consistently observed after calibration. The medians of the longitudinal differences in AI, aortic systolic BP and aortic mean BP between the waves were <2% before calibration, but increased slightly to <5% after calibration. Most of the risk factors had moderate to high tracking stability. Muscle mass and serum creatinine were among those with relatively high tracking stability.

CONCLUSIONS

The longitudinal differences in parameters between the waves were overall modest after calibration, suggesting that calibration may attenuate longitudinal differences inflated by non-biological factors such as systematic drift due to batch effect. Changes of the hemodynamic parameters are robust over time and not entirely attributable to age. Our study also demonstrated moderate to high tracking stability for most of the parameters.

The estimation of glomerular filtration in acute and critical illness: Challenges and opportunities

Recent events have made it apparent that the creatinine based estimating equations for glomerular filtration have their flaws. Some flaws have been known for some time; others have prompted radical modification of the equations themselves. These issues persist in part owing to the behaviour of the creatinine molecule itself, particularly in acute and critical illness. There are significant implications for patient treatment decisions, including drug and fluid therapies and choice of imaging modality (contrast vs. non-contrast CT scan for example). An alternative biomarker, Cystatin C, has been used with some success both alone and in combination with creatinine to help improve the accuracy of particular estimating equations. Problems remain in certain circumstances and costs may limit the more widespread use of the alternative assay. This review will explore both the historical and more recent evidence for glomerular filtration estimation, including options to directly measure glomerular filtration (rather than estimate), perhaps the holy grail for both Biochemistry and Nephrology.

Deep Learning Identifies Intelligible Predictors of Poor Prognosis in Chronic Kidney Disease

Early diagnosis and prediction of chronic kidney disease (CKD) progress within a given duration are critical to ensure personalized treatment, which could improve patients' quality of life and prolong survival time. In this study, we explore the intelligibility of machine-learning and deep-learning models on end-stage renal disease (ESRD) prediction, based on readily-accessible clinical and laboratory features of patients suffering from CKD. Eight machine learning models were used to predict whether a patient suffering from CKD would progress to ESRD within three years based on demographics, clinical,and comorbidity information. LASSO, random forest, and XGBoost were used to identify the most significant markers. In addition, we introduced four advanced attribution methods to the deep learning model to enhance model intelligibility. The deep learning model achieved an AUC-ROC of 0.8991, which was significantly higher than that of baseline models. The interpretation generated by deep learning with attribution methods, random forest, and XGBoost was consistent with clinical knowledge, whereas LASSO-based interpretation was inconsistent. Hematuria, proteinuria, potassium, urine albumin to creatinine ratio were positively associated with the progression of CKD, while eGFR and urine creatinine were negatively associated. In conclusion, deep learning with attribution algorithms could identify intelligible features of CKD progression. Our model identified a number of critical, but under-reported features, which may be novel markers for CKD progression. This study provides physicians with solid data-driven evidence for using machine learning for CKD clinical management and treatment.

Advances of perioperative acute kidney injury in elderly patients undergoing non-cardiac surgery

The risk of developing perioperative acute kidney injury (AKI) in elderly patients increases with age. The combined involvement of aging kidneys, coexisting multiple underlying chronic diseases, and increased exposure to potential renal stressors and nephrotoxic drugs or invasive procedures constitute susceptibility factors for AKI in elderly patients. The perioperative AKI in elderly patients undergoing noncardiac surgery has its own specific population characteristics, so it is necessary to further explore the characteristics of AKI in elderly patients in terms of epidemiology, clinical diagnosis, risk factors, and preventive and curative measures to provide meaningful clinical advice to improve prognosis, accelerate recovery, and reduce medical burden in elderly patients. Since AKI has the fastest-growing incidence in older patients and is associated with a worse prognosis, early detection, early diagnosis, and prevention of AKI are important for elderly patients in the perioperative period. Large, multicenter, randomized controlled clinical studies in elderly non-cardiac surgery patients with AKI can be conducted in the future, with the aim of providing the evidence to reduce of the incidence of AKI and to improve the prognosis of patients.

Polygenic scores for estimated glomerular filtration rate in a population of general adults and elderly - comparative results from the KORA and AugUR study

BACKGROUND

Polygenic scores (PGSs) combining genetic variants found to be associated with creatinine-based estimated glomerular filtration rate (eGFR_crea) have been applied in various study populations with different age ranges. This has shown that PGS explain less eGFR_crea variance in the elderly. Our aim was to understand how differences in eGFR variance and the percentage explained by PGS varies between population of general adults and elderly.

RESULTS

We derived a PGS for cystatin-based eGFR (eGFR_cys) from published genome-wide association studies. We used the 634 variants known for eGFR_crea and the 204 variants identified for eGFR_cys to calculate the PGS in two comparable studies capturing a general adult and an elderly population, KORA S4 (n = 2,900; age 24-69 years) and AugUR (n = 2,272, age ≥ 70 years). To identify potential factors determining age-dependent differences on the PGS-explained variance, we evaluated the PGS variance, the eGFR variance, and the beta estimates of PGS association on eGFR. Specifically, we compared frequencies of eGFR-lowering alleles between general adult and elderly individuals and analyzed the influence of comorbidities and medication intake. The PGS for eGFR_crea explained almost twice as much (R² = 9.6%) of age-/sex adjusted eGFR variance in the general adults compared to the elderly (4.6%). This difference was less pronounced for the PGS for eGFR_cys (4.7% or 3.6%, respectively). The beta-estimate of the PGS on eGFR_crea was higher in the general adults compared to the elderly, but similar for the PGS on eGFR_cys. The eGFR variance in the elderly was reduced by accounting for comorbidities and medication intake, but this did not explain the difference in R²-values. Allele frequencies between general adult and elderly individuals showed no significant differences except for one variant near APOE (rs429358). We found no enrichment of eGFR-protective alleles in the elderly compared to general adults.

CONCLUSIONS

We concluded that the difference in explained variance by PGS was due to the higher age- and sex-adjusted eGFR variance in the elderly and, for eGFR_crea, also by a lower PGS association beta-estimate. Our results provide little evidence for survival or selection bias.

Diagnostic value of neutrophil gelatinase-associated lipocalin (NGAL) as an early biomarker for detection of renal failure in hypertensives: a case-control study in a regional hospital in Ghana

BACKGROUND

Renal failure is one of the most serious vascular effects of hypertension. For better therapy and prevention of complications, early kidney disease identification in these patients is absolutely essential. However, current studies have proposed plasma Neutrophil Gelatinase Associated Lipocalin (pNGAL) to be a better biomarker comparative to serum creatinine (SCr). This study assessed the diagnostic utility of plasma neutrophil gelatinase-associated lipocalin (pNGAL) as a biomarker for early nephropathy diagnosis in hypertensive individuals.

METHODS

This hospital-based case-control study comprised 140 hypertensives and 70 healthy participants. A well-structured questionnaire and patient case notes were used to document relevant demographic and clinical information. 5 ml of venous blood sample was taken to measure fasting blood sugar levels, creatinine, and plasma NGAL levels. All data were analyzed using the Statistical Package for Social Sciences (SPSS release 20.0, copyrite©SPSS Inc.) and a p-value < 0.05 was considered statistically significant.

RESULTS

In this study the plasma neutrophil gelatinase-associated lipocalin (NGAL) levels were significantly higher in cases compared to controls. Hypertensive cases also had significantly higher waist-circumference compared to the control group. The median fasting blood sugar level was significantly higher in cases compared to controls. This study established the use of Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Cockcroft and Gault formula (CG) as the most accurate predictive equations for assessing renal dysfunction. The threshold for NGAL above which renal impairment can be assessed was found to be 109.4 ng/ml (sen-91%, spec. - 68%), 120 ng/ml (sen- 100%, spec- 72%) and 118.6 ng/ml (sen- 83%, spec- 72%) for MDRD, CKD-EPI and CG equations respectively. The prevalence of CKD was 16.4%, 13.6% and 20.7% respectively using the MDRD, CKD-EPI and CG.

CONCLUSION

From this study, pNGAL is a better indicator of kidney impairment in the early stages of CKD as compared with sCr in general hypertensive population.

Acute effects of lithium augmentation on the kidney in geriatric compared with non-geriatric patients with treatment-resistant depression

INTRODUCTION

Lithium augmentation (LA) of antidepressants is a first-line therapy option for treatment-resistant depression (TRD). Nevertheless, it is rarely used in geriatric patients mostly because of the fear of kidney toxicity. The purpose of this study is to investigate estimated glomerular filtration rate (eGFR) changes and number of acute kidney injuries (AKI) using LA in geriatric compared with non-geriatric patients.

METHODS

In a prospective multicenter cohort study, eGFR changes were measured in 201 patients with unipolar depression (n_{age≥65years}  = 29; n_age<65years  = 172) at baseline and over 2-6 weeks of LA. We used linear mixed models to investigate changes in eGFR upon LA and assessed the number of AKIs, according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

RESULTS

Both age groups showed a significant eGFR decline over the course of treatment with lower eGFR in geriatric patients. The lithium serum level (interpretable as "effect of LA") had a significant effect on eGFR decline. Both effects (age group and lithium serum level) on eGFR decline did not influence each other, meaning the effect of LA on eGFR decline did not differ between age groups. Two AKIs were observed in the geriatric age group when serum lithium levels exceeded the therapeutic range of >0.8 mmol/L.

CONCLUSION

This is the first study investigating eGFR change and AKI upon LA for TRD in geriatric compared with non-geriatric patients. Our data suggest that LA, as an effective treatment option in geriatric patients, should be closely monitored to avoid AKIs.

What does the French REIN registry tell us about Stage 4-5 CKD care in older adults?

The aim of this paper is to illustrate all the clinical epidemiology searches made within the French network REIN to improve CKD stage 4-5 care in older adults. We summarize various studies describing clinical practice, care organization, prognosis and health economics evaluation in order to develop personalized care plans and decision-making tools. In France, for 20 years now, various databases have been mobilized including the national REIN registry which includes all patients receiving dialysis or transplantation. REIN data are indirectly linked to the French administrative healthcare database. They are also pooled with data from the PSPA cohort, a multicenter prospective cohort study of patients aged 75 or over with advanced CKD, monitored for 5 years, and the CKD-REIN clinical-based prospective cohort which included 3033 patients with CKD stage 3-4 from 2013 to 2016. During our various research work, we identified heterogeneous trajectories specific to this growing older population, raising ethical, organizational and economic issues. Renal registries will help clinicians, health providers and policy-makers if suitable decision- making tools are developed and validated.

Association of impaired kidney function with dementia and brain pathologies: A community-based cohort study

INTRODUCTION

The relationship between impaired kidney function (KF), dementia, and brain pathologies remains unclear.

METHODS

A total of 1354 dementia- and kidney disease-free participants including 895 with normal and 459 with impaired KF were followed from 2002 until 2020 (median [interquartile range]: 5 [2-9]) to detect incident dementia. KF was assessed at baseline and categorized as normal or impaired. Over the follow-up, 453 participants died and underwent autopsies for neuropathological assessment.

RESULTS

Compared to those with normal KF, the hazard ratios (95% confidence intervals [CIs]) of those with impaired KF was 1.48 (1.15, 1.90)/1.44 (1.10, 1.88) for dementia/Alzheimer's dementia. Furthermore, impaired KF was related to a significantly higher burden of cerebral amyloid angiopathy (CAA; odds ratio = 1.96, 95% CI: 1.17, 3.30), but not to other brain pathologies.

DISCUSSION

Impaired KF is associated with an increased risk of dementia and Alzheimer's dementia. CAA may underlie, in part, this association.

HIGHLIGHTS

Impaired kidney function (KF) was associated with higher dementia and Alzheimer's dementia risk. Impaired KF anticipated dementia and Alzheimer's dementia onset by more than 1.5 years. Impaired KF was significantly related to a higher burden of cerebral amyloid angiopathy (CAA) but not to other brain pathologies.

Kidney disease burden in an Asian Indian population: Effect of the new 2021 serum creatinine CKD-EPI equation

AIMS

CKD-EPI (chronic kidney disease-epidemiological) serum creatinine equation is widely accepted for calculating estimated glomerular filtration rate (eGFR). The effect of transitioning from the older 2009 to the newer race-independent 2021 CKD-EPI equation on the estimated kidney disease burden (eKDB) was studied in an Asian-Indian population.

METHODS

The study included 1156 adults, the two equations were compared for agreement (Bland-Altman and Cohen's kappa) and concordance (Lin's correlation and test for proportions).

RESULTS

The 2021 CKD-EPI increased the eGFR (positive-bias), independent of age-group, gender or presence of type 2 diabetes mellitus (T2DM) and hypertension (HTN). Thus, the eKDB was significantly decreased by 2021 CKD-EPI equation. The agreement was highest for the age-group 31-40 years (95.8 % versus 87.5 % for > 50 years). Besides, the eGFR category was shifted from G3 to G1 in 8.2 % (95 % CI: 6.8-9.9) individuals by 2021 CKD-EPI. The effect of transition on eKDB was greater in individuals > 50 years (7.4 %) or with HTN (6.3 %).

CONCLUSION

In comparison to the old equation, the 2021 CKD-EPI equation increased the eGFR, lowering the eKDB in this Asian-Indian cohort. The degree of lowering was affected by age-group, and presence of T2DM /HTN, but independent of gender.

Identification of core genes and pathways between geriatric multimorbidity and renal insufficiency: potential therapeutic agents discovered using bioinformatics analysis

Background

Geriatric people are prone to suffer from multiple chronic diseases, which can directly or indirectly affect renal function. Through bioinformatics analysis, this study aimed to identify key genes and pathways associated with renal insufficiency in patients with geriatric multimorbidity and explore potential drugs against renal insufficiency.

Methods

The text mining tool Pubmed2Ensembl was used to detect genes associated with the keywords including "Geriatric", "Multimorbidity" and "Renal insufficiency". The GeneCodis program was used to specify Gene Ontology (GO) biological process terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Protein–protein interaction (PPI) networks were constructed using STRING and visualized in Cytoscape. Module analysis was performed using CytoHubba and Molecular Complex Detection (MCODE) plugins. GO and KEGG analysis of gene modules was performed using the Database for Annotation, Visualization and Integrated Discover (DAVID) platform database. Genes clustered in salient modules were selected as core genes. Then, the functions and pathways of core genes were visualized using ClueGO and CluePedia. Finally, the drug-gene interaction database was used to explore drug-gene interactions of the core genes to identify drug candidates for renal insufficiency in patients with geriatric multimorbidity.

Results

Through text mining, 351 genes associated with "Geriatric", "Multimorbidity" and "Renal insufficiency" were identified. A PPI network consisting of 216 nodes and 1087 edges was constructed and CytoHubba was used to sequence the genes. Five gene modules were obtained by MCODE analysis. The 26 genes clustered in module1 were selected as core candidate genes primarily associated with renal insufficiency in patients with geriatric multimorbidity. The HIF-1, PI3K-Akt, MAPK, Rap1, and FoxO signaling pathways were enriched. We found that 21 of the 26 selected genes could be targeted by 34 existing drugs.

Conclusion

This study indicated that CST3, SERPINA1, FN1, PF4, IGF1, KNG1, IL6, VEGFA, ALB, TIMP1, TGFB1, HGF, SERPINE1, APOA1, APOB, FGF23, EGF, APOE, VWF, TF, CP, GAS6, APP, IGFBP3, P4HB, and SPP1 were key genes potentially involved with renal insufficiency in patients with geriatric multimorbidity. In addition, 34 drugs were identified as potential agents for the treatment and management of renal insufficiency.

The Importance of Continuous Glucose Monitoring-derived Metrics Beyond HbA1c for Optimal Individualized Glycemic Control

CONTEXT

Current guidelines recommend assessing glycemic control using continuous glucose monitoring (CGM) and hemoglobin A1c (HbA1c) measurement.

OBJECTIVE

This study aimed to clarify the characteristics of patients who might benefit from CGM metrics in addition to HbA1c monitoring.

METHODS

CGM metrics, specifically time in range (TIR), time below range (TBR), and time above range (TAR), were determined in 999 outpatients with type 2 diabetes and compared between HbA1c categories (HbA1c < 53 mmol/mol [7.0%, HbA1c <  53], HbA1c 53-63 mmol/mol [7.0-7.9%, HbA1c 53-63], HbA1c 64-74 mmol/mol [8.0-8.9%, HbA1c 64-74], and HbA1c ≥ 75 mmol/mol [9.0%, HbA1c ≥  75]) and between patients with identical HbA1c categories who were stratified by age, types of antidiabetic agents, and renal function.

RESULTS

For HbA1c <  53 category, patients aged ≥ 65 years had a significantly higher nocturnal TBR than those aged < 65 years. For HbA1c <  53 and HbA1c 53-63 categories, patients receiving insulin and/or sulfonylureas had a significantly higher TAR and TBR, and a lower TIR than those not receiving these drugs, and for HbA1c 64-74 category, they had a significantly higher TBR. For HbA1c <  53, HbA1c 53-63, and HbA1c 64-74 categories, patients with an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 had a significantly higher TBR during some periods than those with an eGFR ≥ 60.

CONCLUSION

Higher HbA1c levels do not always protect against hypoglycemic episodes. Our data demonstrate that using CGM metrics to complement HbA1c monitoring is beneficial, especially in older people, users of insulin and/or sulfonylureas, and patients with chronic kidney disease.

Comparison of different equations for renal function evaluation as proxies for antibiotic drug clearance: the examples of amoxicillin and cloxacillin

The most appropriate renal function estimation equation to predict drug clearance is a matter of debate. In this study, we compare the Modification of Diet in Renal Disease (MDRD), the Chronic Kidney Disease Epidemiology collaboration (CKD-EPI) and the Cockroft-Gault (CG) equations to predict amoxicillin and cloxacillin clearance among hospitalized patients receiving high doses of these antibiotic treatments. This study aimed to compare different equations used to predict amoxicillin and cloxacillin clearance among hospitalized patients receiving amoxicillin or cloxacillin treatments outside the intensive care unit. Data from 128 patients contributing 268 plasma samples was analyzed, and correlations between the equations and the amoxicillin and cloxacillin antibiotic clearance rates were calculated. We found a correlation between antibiotic clearance and all the renal function estimation equations, CG being the best, with a R² of 0.35 for amoxicillin and 0.29 for cloxacillin (compared to 0.26 and 0.21 for MDRD and 0.12 and 0.24 for CKD-EPI). CG should be preferentially used as a proxy for amoxicillin and cloxacillin drug clearance, but the use of completely different tools such as therapeutic drug monitoring could help individualize antibiotic dosage.

Older Women Who Practiced Physical Exercises before the COVID-19 Pandemic Present Metabolic Alterations and Worsened Functional Physical Capacity after One Year of Social Isolation

Background: Because the consequences of the lifestyle changes in older adults associated with the social isolation imposed in response to the COVID-19 pandemic are not fully understood, here, we investigated the effects of one year of social isolation imposed by COVID-19 on the metabolic parameters and functional physical capacity of older women who regularly practiced physical exercises before the pandemic. Methods: Systemic lipid and protein profiles, estimated creatinine clearance (ECC), and functional physical capacity (FPC) were assessed before (January-February 2020) and 12 months after social isolation in 30 older women (mean age 73.77 ± 6.22) who were engaged in a combined-exercise training program for at least 3 years before the COVID-19 pandemic. Results: In this group, we observed increased plasma levels of triglycerides and creatinine, an increase in the time necessary to perform gait speed and time-up-and-go tests, and reduced muscle strength assessed by the handgrip test and ECC post-COVID-19 pandemic relative to values recorded pre-pandemic. In addition, we observed significant correlations (both negative and positive) between anthropometric, some metabolic parameters, and physical tests. Conclusion: One year of interruption of physical exercise practice imposed in response to the COVID-19 pandemic significantly altered some systemic metabolic parameters and worsened ECC and FPC in older women.

Association between Serum Cystatin C levels and long‐term cardiovascular outcomes and all-cause mortality in older patients with obstructive sleep apnea

Background and Aims: To investigate the association between obstructive sleep apnea (OSA) severity and baseline serum cystatin C (Cys-C) concentration and to explore the association between baseline serum Cys-C and long-term cardiovascular outcomes and mortality in older patients with OSA.

Methods: Between January 2015 and October 2017, a total of 1107 consecutive eligible older patients (≥60 years) with OSA were included in this multicenter, prospective cohort study, and baseline demographics, clinical characteristics, sleep parameters, and follow-up outcomes were collected. Participants were divided into different groups based on baseline serum Cys-C levels. The primary end point was major adverse cardiovascular events (MACE) and the secondary end point was all-cause mortality. The correlation between OSA severity and baseline serum Cys-C was evaluated by Spearman correlation analysis. Multivariate Cox regression was used to analyze the association between Cys-C and the incidence of MACE and mortality.

Results: Participants included 672 men and 435 women, with a median age of 66 (range, 60–96) years. At baseline, apnea–hypopnea index (AHI) (r = 0.128, p &lt; 0.05), oxygen desaturation index (ODI) (r = 0.116, p &lt; 0.05), and the lowest pulse oxygen saturation (LSpO2) (r = −0.097, p &lt; 0.05) were correlated with serum Cys-C concentration. During the median follow-up period of 42 months, 97 patients (8.8%) experienced MACE and 40 patients (3.6%) experienced death. The association between serum Cys-C levels and the risk of MACE and all-cause mortality was slow rising shaped. The multivariable Cox regression analysis showed patients with a serum Cys-C concentration of ≥1.14 mg/L had higher risks of MACE (HR = 5.30, 95% CI: 2.28–12.30, p &lt; 0.05) and all-cause mortality (HR = 9.66, 95% CI: 2.09–44.72, p &lt; 0.05) compared with patients with serum Cys-C of ≤0.81 mg/L in older patients with OSA. The receiver-operating characteristic curve showed baseline serum Cys-C levels exhibited moderately capable of identifying patients with a long-term risk of clinical adverse events (MACE and mortality).

Conclusion: OSA severity was positively correlated with serum Cys-C concentration. High levels of Cys-C were independently associated with increased risks of MACE and all-cause mortality in older patients with OSA, suggesting that lowering Cys-C levels should be considered as a therapeutic target, and monitoring serum Cys-C may be beneficial to the favorable prognosis of older patients with OSA.

The Significance of Estimated Glomerular Filtration Rate for Predicting Mortality in Glyphosate Herbicide-Intoxicated Patients: A Single-Center, Retrospective Observational Study

Background: Glyphosate herbicide (GH) is widely used worldwide. It has a higher fatality rate than expected. GH-poisoned cases are increasingly reported. Acute kidney injury in poisoned patients is one of several predictors of GH mortality. The aim of this study was to determine whether estimated glomerular filtration rate (eGFR) could predict kidney injury in GH intoxication. Methods: This was a retrospective study conducted at the emergency department (ED) of a single hospital between January 2004 and December 2021. A total of 434 patients presented with GH intoxication via oral ingestion, and 424 were enrolled. Their demographic characteristics, laboratory variables, complications, and mortality were analyzed to determine clinical predictors associated with GH-induced mortality using a logistic regression analysis. The relationship between GH intoxication and eGFR was determined based on the results of dominance analysis. Additionally, the comparison of creatinine and eGFR was performed through receiver operating characteristic (ROC) curves. Results: A total of 424 GH-poisoned patients were enrolled. Of them, 43 (10.1%) died. In the multivariable analysis, initial GCS (OR: 0.874; 95% CI: 0.765−0.998, p = 0.047), albumin (OR: 0.874; 95% CI: 0.765−0.998, p = 0.027), pH (OR: 0.002; 95% CI: 0.000−0.037, p < 0.001), QTc interval (OR: 1.018; 95% CI: 1.007−1.029, p = 0.001), and eGFR (OR: 0.969; 95% CI: 0.95−0.989, p = 0.003) were independent factors for predicting in-hospital mortality. In the dominance analysis of the relative importance of the predictive factors, pH accounted for the largest proportion at 35.8%, followed by QTc (20.0%), GCS (17.3%), eGFR (17.0%), and albumin (9.9%). Additionally, eGFR had a larger area under the ROC curve (0.846; 95% CI, 0.809−0.879) than that of creatinine (0.811; 95% CI, 0.771−0.848, p = 0.033). Conclusion: In sum, eGFR, considered a surrogate of renal function, was a useful prognostic factor for mortality in glyphosate herbicide-poisoned patients.

Bidirectional relations between depression symptoms and chronic kidney disease

BACKGROUND

Depression and chronic kidney disease (CKD) often coexist. However, both the relations of depression with CKD development and CKD with depression risk were still elusive. We aimed to investigate the bidirectional relations between renal function and depression in a cohort of young and middle-aged adults.

METHODS

Using data from the Coronary Artery Risk Development in Young Adults study, the analysis of depressive symptoms and incident CKD (analysis 1) was performed in 3,731 participants without CKD, and the analysis of renal function and incident depression (analysis 2) was performed in 2,994 participants without depression. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale (-CES-D), and depression was defined as CES-D scores ≥16 or self-reported history of depression or antidepressant medication use. CKD was defined as estimated glomerular filtration rate <60 ml/min/1.73 m² or urinary albumin to creatinine ratio ≥30 mg/g.

RESULTS

In analysis 1, 485 participants developed incident CKD during 61,202 person-years of follow-up, and CES-D scores (≥16 vs. <16; adjusted HR, 1.28; 95% CI, 1.04 to 1.59) were significant positive associated with incident CKD. In analysis 2, 1,029 participants developed incident depression during 42,927 person-years of follow-up, and CKD was significantly associated with a 36% increased risk of incident depression compared to non-CKD (HR, 1.36; 95% CI, 1.05 to 1.76).

LIMITATIONS

Depressive symptoms were only assessed using CES-D score, which is not the gold standard for the clinical diagnosis of depression.

CONCLUSIONS

This prospective cohort study monitored over 20 years indicated a bidirectional association between depression and CKD.

Long-term clinical outcomes in older patients with acute venous thromboembolism who have renal impairment

INTRODUCTION

Renal impairment (RI) may induce an inflammatory/procoagulant state as well as platelet dysfunction. Little is known on the prevalence of RI and long-term prognosis of older patients with venous thromboembolism (VTE) who have concomitant RI.

METHODS

In a prospective multicenter cohort, we analyzed 912 patients aged ≥65 years with acute VTE. Using the CKD-EPI formula, we defined three categories of baseline renal function: estimated glomerular filtration rate ≥60 ml/min/1.73m² (no RI), 30-59 ml/min/1.73m² (moderate RI), and <30 ml/min/1.73m² (severe RI). The outcomes were VTE recurrence, major bleeding, and overall mortality. We examined the association between renal function and clinical outcomes using competing risk regression models, adjusting for relevant confounders and periods of anticoagulation.

RESULTS

We followed 912 patients over a median duration of 29.6 months. Overall, 313 (34%) patients had moderate and 51 (6%) severe RI. One hundred and seven patients (12%) had VTE recurrence, 125 (14%) had major bleeding, and 186 (20%) died during follow-up. After adjustment, severe RI was associated with a 2-fold increased risk of major bleeding (sub-hazard ratio [SHR] 2.1, 95% CI 1.1-4.0) compared to no RI, but not with VTE recurrence (SHR 0.6, 95% CI 0.2-1.8) or overall mortality (hazard ratio 1.0, 95% CI 0.6-1.9). Moderate RI was not significantly associated with adverse clinical outcomes.

CONCLUSIONS

RI was common among older patients with acute VTE. Severe RI was associated with a 2-fold increased long-term risk of major bleeding, without a risk increase in terms of VTE recurrence and overall mortality. Older patients with moderate RI did not carry worse prognosis.

Analysis of routine blood parameters in patients with amyotrophic lateral sclerosis and evaluation of a possible correlation with disease progression—a multicenter study

Objective

Amyotrophic lateral sclerosis (ALS) pathogenesis is still unclear, its course is considerably variable, and prognosis is hard to determine. Despite much research, there is still a lack of easily accessible markers predicting prognosis. We investigated routine blood parameters in ALS patients regarding correlations with disease severity, progression rate, and survival. Additionally, we analyzed disease and patients' characteristics relating to baseline blood parameter levels.

Methods

We analyzed creatine kinase (CK), albumin (ALB), creatinine (CREA), total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), and triglycerides (TG) levels around time of diagnosis in 1,084 ALS patients. We carried out linear regression analyses including disease and patients' characteristics with each blood parameter to detect correlations with them. Linear regression models were performed for ALSFRS-R at study entry, its retrospectively defined rate of decay and prospectively collected progression rate. Different survival analysis methods were used to examine associations between blood parameters and survival.

Results

We found higher CK (p-value 0.001), ALB (p-value <0.001), CREA (p-value <0.001), and HDL levels (p-value 0.044) at time of diagnosis being associated with better functional status according to ALSFRS-R scores at study entry. Additionally, higher CREA levels were associated with lower risk of death (p-value 0.003).

Conclusions

Our results indicate potential of CK, ALB, CREA, and HDL as disease severity or progression markers, and may also provide clues to ALS pathogenesis. However, these values are highly dependent on other variables, and further careful, longitudinal analyses will be necessary to prove the relevance of our findings.

Clin-Star corner: What is new at the interface of geriatrics and nephrology?

Chronic kidney disease (CKD) is prevalent and burdensome among older adults in the United States. CKD affects at least 15% of the US population, and adults over 65 comprise the largest subset within this group. In this special article, we highlight key findings of three recent original investigations in nephrology and describe each study, relevance to the care of older adults, and current areas of uncertainty that warrant further investigation. Articles relate to removal of the race adjustment in the estimation of kidney function, the use of novel therapeutics to halt CKD progression and improve cardiovascular outcomes, and medication management for short-term pain control in CKD.

Infective Endocarditis in the Elderly: Challenges and Strategies

The specific management of infective endocarditis (IE) in elderly patients is not specifically addressed in recent guidelines despite its increasing incidence and high mortality in this population. The term "elderly" corresponds to different ages in the literature, but it is defined by considerable comorbidity and heterogeneity. Cancer incidence, specifically colorectal cancer, is increased in older patients with IE and impacts its outcome. Diagnosis of IE in elderly patients is challenging due to the atypical presentation of the disease and the lower performance of imaging studies. Enterococcal etiology is more frequent than in younger patients. Antibiotic treatment should prioritize diminishing adverse effects and drug interactions while maintaining the best efficacy, as surgical treatment is less commonly performed in this population due to the high surgical risk. The global assessment of elderly patients with IE, with particular attention to frailty and geriatric profiles, should be performed by multidisciplinary teams to improve disease management in this population.

Rotablation in Patients with Advanced Renal Insufficiency through End-Stage Renal Disease: Short- and Intermediate-Term Results

Objective. Patients with advanced renal insufficiency are at high risk of coronary artery disease (CAD) and complex lesions. Treating complex calcified lesion with rotational atherectomy (RA) in these patients might be associated with higher risks and poorer outcomes. This study was set to evaluate features and outcomes of RA in these patients. Method. Consecutive patients who received coronary RA from April 2010 to April 2018 were queried from the Cath Lab database. The procedural details, angiography, and clinical information were reviewed in detail. Results. A total of 411 patients were enrolled and divided into Group A (baseline serum creatinine <5 mg/dl, n = 338) and Group B (baseline serum creatinine ≥ 5 mg/dl through ESRD, n = 73). Most patients had high-risk features (65.7% of acute coronary syndrome (ACS), 14.1% of ischemic cardiomyopathy, and 5.1% of cardiogenic shock). Group B patients were significantly younger (66.8 ± 11.4 vs. 75.2 ± 10.7 years, $p<0.001$ ) and had more RCA and LCX but less LAD treated with RA. No difference was found in lesion location, vessel tortuosity, bifurcation lesions, chronic total occlusion, total lesion length, or total lesion numbers between the two groups. Less patients in Group B obtained completion of RA (95.9% vs 99.1%, $p=0.037$ ). There was no difference in the incidence of procedural complication or acute contrast-induced nephropathy. Group B patients had more deaths and MACE while in the hospital. The MACE and CV MACE were also higher in Group B patients at 180 days and one year, mostly due to TLR and TVR. Multivariate regression analysis showed that ACS, age, peripheral artery disease (PAD), advanced renal insufficiency, ischemic cardiomyopathy/shock, and high residual SYNTAX score were independent risk factors for in-hospital MACE, whereas ACS, advanced renal insufficiency, ischemic cardiomyopathy/shock, triple-vessel disease, and PAD independently predicted MACE at 6 months. Conclusions. Rotablation is feasible, safe, and could be carried out with very high success rate in very-high-risk patients with advanced renal dysfunction through ESRD without an increase in procedural complication.

Renal decline in patients with non-valvular atrial fibrillation treated with rivaroxaban or warfarin: A population-based study from the United Kingdom

BACKGROUND

Reports suggest that renal decline is greater among patients with non-valvular atrial fibrillation (NVAF) treated chronically with warfarin vs. some non-vitamin K antagonist oral anticoagulants.

METHODS AND RESULTS

Using primary care electronic health records from the United Kingdom we followed adults with NVAF and who started rivaroxaban (20 mg/day, N = 5338) or warfarin (N = 6314), excluding those with estimated glomerular filtration rate (eGFR) <50 ml/min/1.73m², end-stage renal disease (ESRD) or no eGFR or serum creatinine (SCr) values recorded in the previous year. Outcomes were: doubling SCr levels, ≥30% decline in eGFR and progression to ESRD. We calculated adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome. Average eGFR slope was estimated using mixed model regression. After a mean follow-up 2.5 years, the number of incident cases of adverse renal events within the two cohorts was: doubling SCr (n = 322), ≥30% decline in eGFR (n = 1179), and progression to ESRD (n = 22). Adjusted HRs (95% CIs) for the renal outcomes among rivaroxaban vs. warfarin users were: doubling SCr, 0.63 (0.49-0.81); ≥30% decline in eGFR, 0.76 (0.67-0.86); ESRD, 0.77 (0.29-2.04). Similar results were observed among patients with diabetes or heart failure. Estimated mean decline in renal function over the study period was 2.03 ml/min/1.73 m²/year among warfarin users and 1.65 ml/min/1.73 m²/year among rivaroxaban users (p = 0.03).

CONCLUSIONS

We found clear evidence that patients with NVAF, preserved renal function at baseline and treated with rivaroxaban had a markedly reduced risk and rate of renal decline compared with those treated with warfarin.

Utility of a Score for Predicting Glomerular Filtration Rate Overestimation in Patients with Cardiovascular and Renal Diseases and Their Risk Factors

Objective We recently reported a novel score for the detection of glomerular filtration rate (GFR) overestimation using a creatinine-based equation. We examined the utility of this score in patients with cardiovascular/renal diseases and diabetes mellitus. Methods We enrolled 1,425 patients (65±15 years old; 37% women) who were admitted to our hospital for the management of cardiovascular and renal diseases and their risk factors. Overestimation of the GFR (OE) was defined as a creatinine-based GFR (eGFRcre) ≥120% of the cystatin C-based estimated GFR. The OE score was calculated as the sum of the scores for the body weight, hemoglobin concentration, and blood urea nitrogen (BUN)/serum creatinine (Scr), totaling 1 point if the body weight was <63.0 kg in men or <42.0 kg in women, 1 point if the hemoglobin concentration was <12.4 g/dL in men or <11.0 g/dL in women, and 1 point if the BUN/Scr was >26.5. Results The proportion of patients with OE was 14.2%. The score predicted OE with a sensitivity of 70.8% and a specificity of 99.6%, and the sensitivity was increased in patients ≥75 years old (88.3%) and decreased in diabetics (58.6%). When patients were divided into subgroups by the total score, the frequencies of OE were 8% (59/754), 14% (72/502), 38% (58/151), and 72% (13/18) in patients with scores of 0, 1, 2, and 3, respectively. Conclusion The OE score is useful for detecting elderly cases of cardiovascular and renal diseases in which eGFRcre overestimates the GFR, although its utility is limited in diabetics.

Impact of different renal function equations on direct oral anticoagulant concentrations

The purpose of this study is to investigate the correlation between glomerular filtration rate (GFR) estimated by different renal function equations and non-vitamin K antagonist oral anticoagulant concentration. Atrial fibrillation patients who aged ≥ 20 years and used dabigatran, rivaroxaban, or apixaban for thromboembolism prevention were enrolled to collect blood samples and measure drug concentrations using ultra-high-performance liquid chromatography with tandem mass spectrometry. The GFR was estimated using the Cockroft–Gault formula (abbreviated as creatinine clearance, CrCL), Chronic Kidney Disease Epidemiology Collaboration formula (CKD-EPI) featuring both creatinine and cystatin C, and the Modification of Diet in Renal Disease Study equation (MDRD). Multivariate regression was used to investigate the associations of different renal function estimates with drug concentrations. A total of 511 participants were enrolled, including 146 dabigatran users, 164 rivaroxaban users and 201 apixaban users. Compared to clinical trials, 35.4% of dabigatran, 4.9% of rivaroxaban, and 5.5% of apixaban concentrations were higher than the expected range (p < 0.001). CKD-EPI and MDRD estimates classified fewer patients as having GFR < 50 mL/min than CrCL in all 3 groups. Both CrCL and CKD-EPI were associated with higher-than-expected ranges of dabigatran or rivaroxaban concentrations. Nevertheless, none of the renal function equations was associated with higher-than-expected apixaban concentrations. For participants aged ≥ 75 years, CKD-EPI may be associated with higher-than-expected trough concentration of dabigatran. In conclusion, CrCL and CKD-EPI both can be used to identify patients with high trough concentrations of dabigatran or rivaroxaban. Among elderly patients who used dabigatran, CKD-EPI may be associated with increased drug concentration.

Acute kidney injury and aging

Our aging population is growing and developing treatments for age-related diseases such as Alzheimer's and Parkinson's disease has taken on an increasing urgency and is accompanied by high public awareness. The already high and rising incidence of acute kidney injury (AKI) in the elderly, however, has received relatively little attention despite the potentially fatal outcomes associated with an episode of AKI in this age group. When discussing AKI and aging, one should consider two aspects: first, elderly patients have an increased susceptibility to an AKI episode, and second, they have decreased kidney repair after AKI given the high incidence of progression to chronic kidney disease (CKD). It is unclear if the same factors that drive the increased susceptibility to AKI could be playing a role in the decreased repair capacity or if they are totally different and unrelated. This review will examine current knowledge on the risk factors for the increased susceptibility to AKI in the elderly and will also explore potential aspects that might contribute to a decreased kidney repair response in this age group.

Kidney Function Is Not Related to Brain Amyloid Burden on PET Imaging in The 90+ Study Cohort

Cognitive decline is common in chronic kidney disease (CKD). While the evidence of vascular cognitive impairment in this population is robust, the role of Alzheimer's pathology is unknown. We evaluated serum cystatin C-estimated glomerular filtration rate (eGFR), brain amyloid-β positron emission tomography (PET) imaging, and cognitive function in 166 participants from The 90+ Study. Mean age was 93 years (range 90-107) and 101 (61%) were women; 107 participants had normal cognitive status while 59 participants had cognitive impairment no dementia (CIND) or dementia. Mean ± standard deviation cystatin C was 1.59 ± 0.54 mg/L with eGFR 40.7 ± 18.7 ml/min/1.73m2. Higher amyloid-β burden was associated with dementia, but not with age, diabetes, hypertension, or cardiovascular disease. We found no association between brain amyloid-β burden and cystatin C eGFR. We previously reported that kidney function was associated with cognition and cerebral microbleeds in the same cohort of oldest-old adults (90+ years old). Collectively, these findings suggest that microvascular rather than Alzheimer's pathology drives CKD-associated cognitive dysfunction in this population.

Analysis of inappropriate prescribing in elderly patients of the Swiss HIV Cohort Study reveals gender inequity

BACKGROUND

The extent of inappropriate prescribing observed in geriatric medicine has not been thoroughly evaluated in people ageing with HIV. We determined the prevalence of and risk factors for inappropriate prescribing in individuals aged ≥75 years enrolled in the Swiss HIV Cohort Study.

METHODS

Retrospective review of medical records was performed to gain more insights into non-HIV comorbidities. Inappropriate prescribing was screened using the Beers criteria, the STOPP/START criteria and the Liverpool drug-drug interactions (DDIs) database.

RESULTS

For 175 included individuals, the median age was 78 years (IQR 76-81) and 71% were male. The median number of non-HIV comorbidities was 7 (IQR 5-10). The prevalence of polypharmacy and inappropriate prescribing was 66% and 67%, respectively. Overall, 40% of prescribing issues could have deleterious consequences. Prescribing issues occurred mainly with non-HIV drugs and included: incorrect dosage (26%); lack of indication (21%); prescription omission (drug not prescribed although indicated) (17%); drug not appropriate in elderly individuals (18%) and deleterious DDIs (17%). In the multivariable logistic regression, risk factors for prescribing issues were polypharmacy (OR: 2.5; 95% CI: 1.3-4.7), renal impairment (OR: 2.7; 95% CI: 1.4-5.1), treatment with CNS-active drugs (OR: 2.1; 95% CI: 1.1-3.8) and female sex (OR: 8.3; 95% CI: 2.4-28.1).

CONCLUSIONS

Polypharmacy and inappropriate prescribing are highly prevalent in elderly people living with HIV. Women are at higher risk than men, partly explained by sex differences in the occurrence of non-HIV comorbidities and medical care. Medication reconciliation and periodic review of prescriptions by experienced physicians could help reduce polypharmacy and inappropriate prescribing in this vulnerable, growing population.

Marie B, Milavetz G, Herr K. Cannabidiol (CBD) Use by Older Adults for Acute and Chronic Pain

Legalization of cannabidiol (CBD) products has ignited interest in clinical practice and research. One desired indication includes possible pain-relieving effects of CBD. The purposes of the current article are to (1) clarify terminology relevant to cannabinoids; (2) explain and understand the pharmacotherapeutics of CBD; (3) examine research of the current use of CBD by older adults for treating pain; (4) discuss safety considerations with using CBD products; and (5) provide best practice recommendations for clinicians as they advise their older adult patients. A review of the literature demonstrated mixed results on the efficacy of CBD in relieving pain in older adults. There is inconsistency in the labeling of over-the-counter CBD products that can result in safety issues and will require more federal quality control. Likewise, gaps in knowledge regarding safety and efficacy of CBD use in older adults are vast and require further research. [Journal of Gerontological Nursing, 47(7), 6-15.].

The risk of polypharmacy and potentially inappropriate drugs in residential care dementia patients: tips from the PharE study

AIMS

The aims of the present study, conducted in two regions of Italy, Calabria and Piedmont, were to assess the use of inappropriate drugs according to the Beers Criteria and to study the possible drug-drug interactions.

METHODS

Data were obtained retrospectively from 972 residential care patients between 2016 and 2018. Mean age was 82.4 ± 8.4 years, with a prevalence of women (64.8%). Activities of daily living, instrumental activities of daily living, Mini-Mental State Examination, Cumulative Illness Rating Scale, Neuropsychiatric Inventory Scale and number and kind of drugs were recorded. A classification of potential inappropriate drugs was made according to the Beers criteria. Data were collected through an Excel file able to gather the main information. In the case of suspected adverse event, Naranjo Scale was applied. The study of possible drug-drug interactions was made by Micromedex 2.0.

RESULTS

Functional and cognitive impairments, comorbidities and number of drugs were assessed. The bivariate relationship between number of drugs and glomerular filtration rate assessed by CKD-EPI showed that the higher was the number of drugs used, the worst was kidney function assessment (p = 0.0001). The most frequent inappropriate drugs were anticholinergic drugs, tricyclics antidepressants, long-half-life benzodiazepines, antipsychotics and proton pump inhibitors.

CONCLUSIONS

These data are very interesting and show the need for an accurate choice of drugs in elderly people and for starting a wise deprescribing procedure.