Comparing the impact of older age on outcome in chronic kidney disease of different etiologies: a prospective cohort study

Age-modified risk factors for mortality of non-elderly adult kidney transplant recipients: a retrospective database analysis

PURPOSE

We aimed to investigate the role of the recipient's age strata in modifying the associations between risk factors and mortality in non-elderly adult kidney transplant (KT) recipients (KTR).

METHODS

We stratified 108,695 adult KTRs between 2000 and 2016 with conditional 1-year survival after KT into cohorts based on age at transplant: 18-49 years and 50-64 years. We excluded KTRs aged < 18 years or > / = 65 years. KTRs were observed for 5 years during the 2nd through 6th years post-KT for the outcome, all-cause mortality.

RESULTS

Increasing recipient age strata (18-49-year-old and 50-64-year-old) correlated with decreasing 6-year post-KT survival rates conditional on 1-year survival (79% and 57%, respectively, p < 0.0001). Middle adult age stratum was associated with a higher risk of all-cause mortality than young adult age stratum in KTRs of Hispanic/Latino and other races [HR = 1.23, 95% CI = 1.04-1.45 and HR = 1.51, 95% CI = 1.16-1.97, respectively] and with a primary native renal diagnosis of hypertension or glomerulonephritis [HR = 1.32, 95% CI = 1.12-1.55 and HR = 1.29, 95% CI = 1.10-151, respectively]. When compared with the young adult age stratum, the middle adult age stratum had a mitigating effect on the higher risk of mortality associated with sirolimus-mycophenolate or sirolimus-tacrolimus than the standard calcineurin inhibitor-mycophenolate regimen [HR = 0.75, 95% CI = 0.57-0.99 and HR = 0.71, 95% CI = 0.57-0.89, respectively].

CONCLUSION

Among adult non-elderly KTRs, the age strata, 18-49 years, and 50-64 years, have varying modifying effects on the strength and direction of associations between some specific risk factors and all-cause mortality.

Chronic Kidney Disease in Inflammatory Bowel Disease: a Systematic Review and Meta-analysis

Inflammatory bowel disease [IBD] is associated with various immune-mediated disorders including spondylarthritis, pyoderma gangrenosum, primary sclerosing cholangitis, and uveitis. Chronic kidney disease [CKD] is defined by a reduction in kidney function (estimated glomerular filtration rate [eGFR] less than 60 ml/min/1.73m2] and/or damage markers that are present for at least 3 months, regardless of the aetiology. Case reports and cohort studies suggest that IBD is associated with CKD. The extent and magnitude of a potential association is unknown. A comprehensive search was conducted in EMBASE, MEDLINE, Web of Science, the Cochrane database, and SCOPUS. Two separate reviewers were involved in the process of article selection and evaluation. Odds ratios were calculated in those papers with a comparison between an IBD population and a non-IBD control population, the Mantel Haenszel test was employed, using a random effect model. The systematic review was registered in PROSPERO [RD42023381927]. A total of 54 articles was included in the systematic review. Of these, eight articles included data on prevalence of CKD in IBD patients [n = 102 230] vs healthy populations [n = 762 430]. Of these, diagnosis of CKD was based on International Classification of Diseases [ICD] codes in five studies vs on eGFR in three studies. The overall odds ratio of developing CKD in the IBD population is 1.59, [95% CI 1.31-1.93], without any difference between studies using diagnostic coding (odds ratio [OR] 1.70, 95% CI 1.33-2.19] vs diagnosis based on eGFR [OR 1.36, 95% CI 1.33-1.64]. IBD is associated with a clinically meaningful increased CKD prevalence. We provide recommendations on diagnostic evaluation, as well as suggestions for future research.

Comparison of chronic kidney disease progression and associated complications between geriatric and non-geriatric groups

There is no consensus on the physiologic decline in estimated glomerular filtration rate (GFR) due to geriatric conditions related with the aging or chronic kidney disease (CKD) itself. In this study, we aimed to compare the CKD progression and associated complications in a large sample of geriatric and non-geriatric patients. The data of in 506 patients at age between 30 to 90 years and diagnosed with CKD at stage 2 and above (15 mL/min/1.73 m2 ≤ eGFR < 90 mL/min/1.73 m2) were collected retrospectively and compared among geriatric (>65 years old) and non-geriatric individuals. The rate of hypertension was higher in geriatrics compared to non-geriatrics (96.6% vs 91.9%, P = .04). Among laboratory findings, only PTH level was significantly lower and HCO3 concentration was higher in geriatrics compared to non-geriatrics (P = .02, P < .001, respectively). There was no significant difference in last measured eGFR (P = .99) while that measured 4 years ago was lower in geriatrics compared to that of non-geriatrics (P < .001). eGFR change was smaller in geriatrics compared to non-geriatrics (P < .001), and rate of progressive renal disease among non-geriatric group (39%) was found to be significantly higher than in the geriatrics (17.2%) (P < .001). The prevalence of hyperkalemia was lower in geriatrics at stage 3a (P = .02); prevalence of hyperparathyroidism was lower in those at stage 3b (P = .02) and lastly the acidosis was observed significantly lower in geriatric patients at stage 3a, 3b, and 4 compared to the non-geriatrics at corresponding stages (P < .001, P = .03, and P = .04, respectively). The eGFR change was significantly smaller in geriatrics at stage 3b and 4 (P < .001 and P = .04, respectively) while the rate of progressed renal disease was lower in geriatrics at stage 3a and 3b (21.1% vs 9.9%, P = .03 and 41.2% vs 11.1%, P < .001, respectively). eGFR change in 4-year period and the rates of progressive renal disease are higher in the non-geriatrics and also the prevalence of secondary complications of CKD, such as hyperparathyroidism, acidosis, and hyperkalemia, are higher in non-geriatrics. This may reflect that decline of GFR in geriatric individuals is at least partially related to physiological aging rather than kidney disease. Therefore, devising age related CKD definitions might be appropriate.

Antihypertensive prescribing patterns in non-dialysis dependent chronic kidney disease: Findings from the Salford Kidney Study

BACKGROUND

Hypertension is commonly observed in patients living with chronic kidney disease (CKD). Finding an optimal treatment regime remains challenging due to the complex bidirectional cause-and-effect relationship between hypertension and CKD. There remains variability in antihypertensive treatment practices.

AIM

To analyze data from the Salford Kidney Study database in relation to antihypertensive prescribing patterns amongst CKD patients.

METHODS

The Salford Kidney Study is an ongoing prospective study that has been recruiting CKD patients since 2002. All patients are followed up annually, and their medical records including the list of medications are updated until they reach study endpoints [starting on renal replacement therapy or reaching estimated glomerular filtration rate (eGFR) expressed as mL/min/1.73 m2 ≤ 10 mL/min/1.73 m2, or the last follow-up date, or data lock on December 31, 2021, or death]. Data on antihypertensive prescription practices in correspondence to baseline eGFR, urine albumin-creatinine ratio, primary CKD aetiology, and cardiovascular disease were evaluated. Associations between patients who were prescribed three or more antihypertensive agents and their clinical outcomes were studied by Cox regression analysis. Kaplan-Meier analysis demonstrated differences in survival probabilities.

RESULTS

Three thousand two hundred and thirty non-dialysis-dependent CKD patients with data collected between October 2002 and December 2019 were included. The median age was 65 years. A greater proportion of patients were taking three or more antihypertensive agents with advancing CKD stages (53% of eGFR ≤ 15 mL/min/1.73 m2 vs 26% of eGFR ≥ 60 mL/min/1.73 m2, P < 0.001). An increased number of patients receiving more classes of antihypertensive agents was observed as the urine albumin-creatinine ratio category increased (category A3: 62% vs category A1: 40%, P < 0.001), with the upward trends particularly noticeable in the number of individuals prescribed renin angiotensin system blockers. The prescription of three or more antihypertensive agents was associated with all-cause mortality, independent of blood pressure control (hazard ratio: 1.15; 95% confidence interval: 1.04-1.27, P = 0.006). Kaplan-Meier analysis illustrated significant differences in survival outcomes between patients with three or more and those with less than three antihypertensive agents prescribed (log-rank, P < 0.001).

CONCLUSION

Antihypertensive prescribing patterns in the Salford Kidney Study based on CKD stage were consistent with expectations from the current United Kingdom National Institute of Health and Care Excellence guideline algorithm. Outcomes were poorer in patients with poor blood pressure control despite being on multiple antihypertensive agents. Continued research is required to bridge remaining variations in hypertension treatment practices worldwide.

Disease Burden and Epidemiological Trends of Chronic Kidney Disease at the Global, Regional, National Levels from 1990 to 2019

BACKGROUND

Chronic kidney disease (CKD) is a serious public health issue worldwide, but the disease burden of CKD caused by different etiologies and changing trends has not been fully examined.

METHODS

We collected data from Global Burden of Disease Study 2019 (GBD 2019), including incident cases, age-standardized incidence rate (ASIR), disability-adjusted life years (DALYs), and age-standardized DALY rate between 1990 and 2019 by region, etiology, age, and sex, and calculated the estimated annual percentage change (EAPC) of the rate to evaluate the epidemiological trends.

RESULTS

Globally, incident cases of CKD increased from 7.80 million in 1990 to 18.99 million in 2019, and DALYs increased from 21.50 million to 41.54 million. ASIR increased with an EAPC of 0.69 (95% uncertainty interval [UI] 0.49-0.89) and reached 233.65 per 100,000 in 2019, while the age-standardized DALY rate increased with an EAPC of 0.30 (95% UI 0.17-0.43) and reached 514.86 per 100,000. North Africa and the Middle East, central Latin America, and North America had the highest ASIR in 2019. Central Latin America had the highest age-standardized DALY rate, meanwhile. Almost all countries experienced an increase in ASIR, and over 50% of countries had an increasing trend in age-standardized DALY rate from 1990 to 2019. CKD due to diabetes mellitus type 2 and hypertension accounted for the largest disease burden with 85% incident cases and 66% DALYs in 2019 of known causes, with the highest growth in age-standardized DALY rate and a similar geographic pattern to that of total CKD. Besides, the highest incidence rate of total and four specific CKDs were identified in people aged 70 plus years, who also had the highest DALY rate with a stable trend after 2010. Females had a higher ASIR, while males had a higher age-standardized DALY rate, the gap of which was most distinctive in CKD due to hypertension.

CONCLUSION

The disease burden of CKD remains substantial and continues to grow globally. From 1990 to 2019, global incident cases of CKD have more than doubled and DALYs have almost doubled, and surpassed 40 million years. CKD due to diabetes mellitus type 2 and hypertension contributed nearly 2/3 of DALYs in 2019 of known causes, and had witnessed the highest growth in age-standardized DALY rate. Etiology-specific prevention strategies should be placed as a high priority on the goal of precise control of CKD.

Using Data Mining Techniques to Predict Chronic Kidney Disease: A Review Study

One of the growing global health problems is chronic kidney disease (CKD). Early diagnosis, control, and management of chronic kidney disease are very important. This study considers articles published in English between 2016 and 2021 that use classification methods to predict kidney disease. Data mining models play a vital role in predicting disease. Through our study, data mining techniques of support vector machine, Naive Bayes, and k-nearest neighbor had the highest frequency. After that, random forest, neural network, and decision tree were the most common data mining techniques. Among the risk factors associated with chronic kidney disease, respectively, risk factors of albumin, age, red blood cells, pus cells, and serum creatinine had the highest frequency in these studies. The highest number of best yields was allocated to random forest technique. Reviewing larger databases in the field of kidney disease can help to better analyze the disease and ensure the risk factors extracted.

[Assessment of the progression dynamics of chronic kidney disease in elderly patients with type 2 diabetes mellitus.]

The aim of work is identification and evaluation of clinical factors influencing the dynamics of progression of chronic kidney disease in elderly patients with type 2 diabetes. In a population sample of elderly patients with type 2 diabetes, a cross-sectional observational study of clinical indicators of the standard program of dispensary observation was performed. Primary medical data were collected using the AWPE 2.0 program. 118 protocols of outpatient consultations, including 69 clinical indicators, were selected according to the compliance criteria. To assess the dynamics of the progression of chronic kidney disease, the original calculated diagnostic parameter «Glomerular filtration rate reduction index» (GFR RI) was used. A detailed clinical justification of the calculated diagnostic parameter GFR RI is given; correlations between quantitative and qualitative clinical indicators and GFR RI in a sample of elderly patients with type 2 diabetes are determined; statistically significant differences in clinical factors were revealed in groups identified by the rate of progression of CKD with a threshold value of 3,83 ml/min on 1,73 m2 per year, including medicamental. The proposed diagnostic parameter GFR RI allows us to give an objective assessment of the dynamics of the progression of CKD in elderly patients with type 2 diabetes; when identifying the groups of «slow» and «fast» progression of CKD, significant differences in the following clinical factors were revealed: the level of glycemia, BMI, the experience of diabetes and insulin therapy, the total dose of insulin and sulfonylureas, the presence of concomitant hypertension.

Aging and Renal Disease: Old Questions for New Challenges

Chronic kidney disease (CKD) is a growing problem among aging population, and the number of individuals at risk of end stage renal disease is rising. Part of the reason lies in incomplete understanding of the pathways underlying renal aging and kidney disease, as well as insufficient delivery of evidence-based treatment to elderly patients with CKD. This review aims to address these unsolved issues by delineating updated mechanisms of renal senescence and summarizing recent findings on key clinical aspects of CKD in the elderly. Challenges and obstacles in caring for older people with CKD are discussed, with an emphasis on modification of risk factors, prevention of acute kidney injury, stabilization of progression and decision on dialysis initiation.

Elderly Patients in a Large Nephrology Unit: Who Are Our Old, Old-Old and Oldest-Old Patients?

The world population is aging, and the prevalence of chronic kidney disease (CKD) is increasing. Whether this increase is also due to the methods currently being used to assess kidney function in the elderly is still a matter of discussion. We aimed to describe the actual referral pattern of CKD patients in a large nephrology unit and test whether the use of different formulae to estimate kidney function could affect the staging and the need for specialist care in the older subset of our population. In 2019, 1992 patients were referred to our center. Almost 28% of the patients were aged ≥80 and about 6% were ≥90 years old. Among the causes of kidney disease, glomerulonephritis displayed a higher prevalence in younger patients whereas hypertensive or diabetic kidney disease were more prevalent in older patients. The prevalence of referred patients in advanced CKD stages increased with age; estimated glomerular filtration rate (eGFR) decreased with age regardless of which equation was used (chronic kidney disease epidemiology collaboration (CKD-EPI), Lund–Malmö Revised (LMR), modification of diet in renal disease (MDRD), Full Age Spectrum (FAS), or Berlin Initiative Study 1 (BIS)). With CKD-EPI as a reference, MDRD and FAS underestimated the CKD stage while LMR overestimated it. The BIS showed the highest heterogeneity. Considering an eGFR threshold limit of 45 mL/min for defining “significant” CKD in patients over 65 years of age, the variability in CKD staging was 10% no matter which equation was used. Our study quantified the weight of “old” and “old-old” patients on follow-up in a large nephrology outpatient unit and suggested that with the current referral pattern, the type of formula used does not affect the need for CKD care within the context of a relatively late referral, particularly in elderly patients.

Dietary satisfaction and quality of life in chronic kidney disease patients on low-protein diets: a multicentre study with long-term outcome data (TOrino-Pisa study)

BACKGROUND

Concerns about adherence and quality of life (QoL) limit the diffusion of low-protein diets (LPDs) as a way to slow chronic kidney disease (CKD) progression and postpone dialysis. The aim of this multicentre study is to assess dietary satisfaction in stable CKD patients.

METHODS

This was a multicentre cross-sectional study with long-term follow-up data. Prevalent patients on LPD for at least 6 months were selected in four Italian centres. QoL was assessed using the World Health Organization Quality of Life questionnaire, and diet satisfaction with the Modification of Diet in Renal Disease satisfaction questionnaire. Comorbidity was assessed by Charlson Comorbidity Index, estimated glomerular filtration rate (eGFR) was calculated by the CKD Epidemiology Collaboration equation and protein intake by Maroni-Mitch formula. Survival was analysed with Kaplan-Meier curves and Cox Proportional Hazard Model.

RESULTS

Four hundred and twenty-two CKD Stages 3-5 patients were enrolled. Over 95% were on moderately restricted diets (0.6 g/kg/day). Compliance was good (protein intake: 0.59 g/kg/day at baseline, 0.72 at the end of follow-up). Median dietary satisfaction was 4 on a 1-5 scale. QoL was not affected by the type of diet, but was influenced by age, comorbidity and setting of care. Two years later, at the end of follow-up, 66.6% of the patients were still on a diet; the main causes of discontinuation were dialysis and death. The dropout rate was low (5.5%); in Cox analysis, patient and renal survival were influenced by age and eGFR, but not by QoL, setting of care or type of diet.

CONCLUSIONS

LPDs are compatible with high dietary satisfaction and minimal dropout, at least in patients who are able to follow such a diet for at least 6 months.

Trends and risk factors of elderly-onset Crohn’s disease: A nationwide cohort study

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing in Asia. Numerous risk factors associated with IBD development have been investigated.

AIM

To investigate trends and environmental risk factors of Crohn’s disease (CD) diagnosed in persons aged ≥ 40 years in South Korea.

METHODS

Using the National Health Insurance Service database, a total of 14060821 persons aged > 40 years who underwent national health screening in 2009 were followed up until December 2017. Patients with newly diagnosed CD were enrolled and compared with non-CD cohort. CD was identified according to the International Classification of Diseases 10th revision and the rare/intractable disease registration program codes from the National Health Insurance Service database. The mean follow-up periods was 7.39 years. Age, sex, diabetes, hypertension, smoking, alcohol consumption, regular exercise, body mass index, anemia, chronic kidney disease (CKD) and dyslipidemia were adjusted for in the multivariate analysis model.

RESULTS

During the follow-up, 1337 (1.33/100000) patients developed CD. Men in the middle-aged group (40-64 years) had a higher risk than women [adjusted hazard ratio (aHR) 1.46, 95% confidence interval (CI): 1.29-1.66]; however, this difference tended to disappear as the age of onset increases. In the middle-aged group, patients with a history of smoking [aHR 1.46, 95%CI: 1.19-1.79) and anemia (aHR 1.85, 95%CI: 1.55-2.20) had a significantly higher CD risk. In the elderly group (age, ≥ 65 years), ex-smoking and anemia also increased the CD risk (aHR 1.68, 95%CI: 1.22-2.30) and 1.84 (95%CI: 1.47-2.30, respectively). Especially in the middle-aged group, those with CKD had a statistically elevated CD risk (aHR 1.37, 95%CI: 1.05-1.79). Alcohol consumption and higher body mass index showed negative association trend with CD incidence in both of the age groups. [Middle-aged: aHR 0.77 (95%CI: 0.66-0.89) and aHR 0.73 (95%CI: 0.63-0.84), respectively] [Elderly-group: aHR 0.57 (95%CI: 0.42-0.78) and aHR 0.84 (95%CI 0.67-1.04), respectively]. For regular physical activity and dyslipidemia, negative correlation between CD incidences was proved only in the middle-aged group [aHR 0.88 (95%CI: 0.77-0.89) and aHR 0.81 (95%CI: 0.68-0.96), respectively].

CONCLUSION

History of cigarette smoking, anemia, underweight and CKD are possible risk factors for CD in Asians aged > 40 years.

Beyond chronic kidney disease: the diagnosis of Renal Disease in the Elderly as an unmet need. A position paper endorsed by Italian Society of Nephrology (SIN) and Italian Society of Geriatrics and Gerontology (SIGG)

The dramatic increase in prevalence of chronic kidney disease (CKD) with ageing makes the recognition and correct referral of these patients of paramount relevance in order to implement interventions preventing or delaying the development of CKD complications and end-stage renal disease. Nevertheless, several issues make the diagnosis of CKD in the elderly cumbersome. Among these are age related changes in structures and functions of the kidney, which may be difficult to distinguish from CKD, and multimorbidity. Thus, symptoms, clinical findings and laboratory abnormalities should be considered as potential clues to suspect CKD and to suggest screening. Comprehensive geriatric assessment is essential to define the clinical impact of CKD on functional status and to plan treatment. Correct patient referral is very important: patients with stage 4-5 CKD, as well as those with worsening proteinuria or progressive nephropathy (i.e. eGFR reduction > 5 ml/year) should be referred to nephrologist. Renal biopsy not unfrequently may be the key diagnostic exam and should not be denied simply on the basis of age. Indeed, identifying the cause(s) of CKD is highly desirable to perform a targeted therapy against the pathogenetic mechanisms of CKD, which complement and may outperform in efficacy the general measures for CKD.

Generalizability of SPRINT-CKD cohort to CKD patients referred to renal clinics

BACKGROUND

The Systolic Blood Pressure Intervention Trial-CKD substudy (SPRINT-CKD) has suggested a lower blood pressure (BP) target in CKD patients. However, it is questionable whether the SPRINT-CKD results may be generalized to CKD patients under nephrology care.

METHODS

To compare SPRINT-CKD cohort versus referred CKD patients in terms of patients' risk profile and outcomes, we pooled four prospective cohorts of consecutive CKD patients referred to 40 Italian renal clinics. We implemented the same inclusion/exclusion criteria adopted in SPRINT and same endpoints: (1) a composite of fatal and non-fatal cardiovascular (CV) events (2) all-cause mortality and (3) ESRD (composite of chronic dialysis, transplantation or 50% eGFR decline). Findings were compared with those attained in the control arm of SPRINT-CKD trial that mirrored standard BP management in clinical practice.

RESULTS

Out of 2847 patients referred to renal clinics, only 20.1% (n = 571) were identified as eligible for SPRINT-CKD. Age (72 ± 9 years), gender (42.2% female) and systolic BP (142 ± 10 mmHg) did not differ from the SPRINT-CKD while referred patients had a worse risk profile at baseline: larger prevalence of prior CV disease (25.7% versus 19.5%), higher Framingham risk score (31.9 ± 14.6% versus 27.2 ± 24.7%) and lower GFR (38 ± 11 versus 48 ± 10 mL/min/1.73 m²). During 4.0 years of follow-up, 86 CV events (50 fatal), 78 all-cause death and 59 ESRD occurred with annual incidence rates higher than those observed in the SPRINT-CKD control group (CV events 4.18 vs 3.19; all-cause death 3.64 vs 2.21; ESRD 2.80 vs 0.41%/year).

CONCLUSIONS

The SPRINT-CKD cohort is poorly representative of the CKD population under nephrology care, thus suggesting that conclusions may not apply to patients referred to nephrologist.

The PIRP project (Prevenzione Insufficienza Renale Progressiva): how to integrate hospital and community maintenance treatment for chronic kidney disease

Chronic kidney disease (CKD) represents a global health burden with great economic impact on healthcare and therefore it requires appropriate interventions by Health Care Systems. The PIRP (Prevenzione Insufficienza Renale Progressiva) project is endorsed and funded by the Emilia-Romagna Regional Health Board and involves all the Nephrology Units of the Emilia-Romagna Region (Italy). The project has a predominantly clinical purpose and is expected to bring about a continuous quality improvement in the treatment of patients with CKD. Its aims are to intercept patients in an early phase of CKD, to delay their illness progression and to prevent cardiovascular complications. An integrated care pathway involving nephrologists, general practitioners (GPs) and other specialists has been created to identify patients to whom ambulatory care targeted on effective, efficient pharmaceutical and dietary treatment as well as on lifestyle modifications is subsequently provided. With the cooperation of GPs, in its 13 years of activity the project identified and followed up more than 25,000 CKD patients, who attended the Nephrology units with more than 100,000 visits. The effects of a closer and joint monitoring of CKD patients by GPs and nephrologists can be quantified by the reduction of the mean annual GFR decline (average annual CKD-EPI change: - 0.34 ml/min), and by the decrease in the overall incidence of patients who annually started dialysis in the Emilia-Romagna Region, that dropped from 218.6 (× million) in 2006 to 197.5 (× million) in 2016, corresponding to about 100 cases.