[Chronic kidney disease in geriatrics]

Chronic kidney disease (CKD) affects almost 10% of the world's population, and over 30% of people aged over 70 [1,2]. The overall incidence of treated CKD is stable in France, but continues to rise sharply in people aged over 85 [3]. In its advanced stages, CKD is associated with numerous complications linked to disturbances in water, acid-base and phosphocalcium balance, as well as anemia and increased cardiovascular risk. A better understanding of risk factors, improved practices to promote nephroprotection, and progress in therapeutic education and preparation for suppletive techniques would help reduce this risk.

[Neurocognitive disorders in chronic kidney disease]

Neurocognitive disorders (NCD) are common in patients with chronic kidney disease (CKD). It is essential to identify and characterize these disorders at an early stage, so as to be able to offer appropriate treatment. In a chronic disease such as CKD, the patient's involvement in decision-making is a major challenge, given the prospects for suppletive treatment: hemodialysis, peritoneal dialysis, kidney transplantation or non-dialytic drug therapy. Many factors are associated with the development and progression of NCD in patients with CKD, and a variety of conditions can influence the outcome of cognitive assessment in these patients.

[Substitution treatments for chronic kidney disease in geriatrics: dialysis, transplantation and medical treatment without dialysis]

Kidney disease, whether acute or chronic, is a particularly common condition in the elderly, due to its main risk factors, the prevalence of which increases with age, and the fact that recovery from acute tubular damage is slower. Wherever possible, treatment of renal failure should be anticipated and discussed with the patient as part of a shared medical decision. Numerous treatment options are available to ensure maximum integration into the patient's life and care plan: renal transplantation for the most robust patients, hemodialysis in a care facility or at home, peritoneal dialysis at home, or medical treatment without dialysis. The choice of one of these treatments must leave the patient free to change his or her treatment modality at any time.

[Acute renal failure in geriatrics]

Acute renal failure (ARF) is a frequent medical problem, affecting 20% of hospitalized patients. Aging leads to functional changes in the kidney, disruptions to hydrosodium homeostasis, and is associated with a higher prevalence of chronic kidney disease due to the impact of numerous chronic illnesses (diabetes, arterial hypertension, benign prostatic hypertrophy, etc.). All these age-related impairments hamper the kidney's ability to adapt to acute events. While elderly subjects can develop all types of AKI, they are particularly at risk of iatrogenic AKI due to polymedication, functional AKI due to a change in their ability to maintain hydrosodium homeostasis, and obstructive AKI linked to urological pathologies.

[Hydrosodium balance in aging]

One of the kidney's major functions is to adjust the water and sodium balance in order to maintain a state of equilibrium. In the course of aging, even in the absence of renal pathology, changes are observed not only in renal macrostructure (reduction in kidney size, increase in the number of cysts), but also in microstructure (arteriosclerosis, glomerulosclerosis, fibrosis and tubular atrophy). All these changes can disrupt the homeostasis of water and sodium balances. The aim of this article is to review the physiology of water and sodium stores, and to assess the impact of aging on the regulatory loops of these different systems.

[The kidney, its anatomy and main functions]

The kidney performs several major functions: it eliminates toxins produced by cellular or xenobiotic metabolism, regulates the homeostasis of the internal environment and plays a hormonal role, producing erythropoietin, calcitriol and renin. Maintaining the body's homeostasis (hydric, ionic [sodium, potassium, calcium, phosphorus, etc.] or acid-base balance) requires the successive action of plasma filtration, followed by reabsorption/secretion mechanisms, which take place in the various portions of the kidney's functional unit known as the nephron. The initial part of the nephron, the glomerulus, is the site of filtration, while the tubule, which collects the glomerular filtrate, is the site of reabsorption/secretion, leading to the composition of the final urine. It's important to understand how these different structures work, before tackling the various disorders that can affect the kidney.

A New Approach for Cognitive Impairment Pattern in Chronic Kidney Disease

BACKGROUND AND HYPOTHESIS

Chronic kidney disease (CKD) is associated with an elevated risk of neurocognitive disorders (NCDs). It remains unclear whether CKD-related NCDs have specific cognitive pattern or are earlier-onset phenotypes of the main NCDs (vascular NCDs and Alzheimer's disease).

METHODS

We used the Mini Mental State Examination score (MMSE) to assess cognitive pattern in 3003 CKD patients (stage 3 to 4) followed up over 5 years in the Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort. After normalizing MMSE scores to a 0-to-100 scale, the associations between the baseline estimated glomerular filtration rate (eGFR, using the CKD-EPI-creatinine formula) and changes in each MMSE domain score were assessed in linear mixed models.

RESULTS

Patients (age: 67±13 years old; males: 65%, mean eGFR: 33±12 ml/min/1.73 m²) had a good baseline cognitive functions: the mean MMSE score was 26.9/30 ±2.9. After adjustment for age, sex, educational level, depression (past or present), cardiovascular risk factors, cerebrovascular disease, a lower baseline eGFR (per 10 ml/min/1.73 m²) was associated with a 0.53-point decrement (p<0.001; 95%CI [-0.98,-0.08]) for orientation, a 1.04-point decrement (p=0.03; 95%CI [-1.96,-0.13]) for attention and calculation, a 0.78-point decrement (p=0.003; 95%CI [-1.30,-0.27]) for language, and a 0.94-point decrement (p=0.02; 95%CI [-1.75,-0.13]) for praxis. Baseline eGFR was not, however, associated with significant changes over time in MMSE domain scores.

CONCLUSION

A lower eGFR in CKD patients was associated with early impairments in certain cognitive domains: praxis, language and attention domains before an obvious cognitive decline. Early detection of NCD in CKD patients must be perform before clinically cognitive decline using preferably tests assessing executive, attentional functions and language than memory test. This could lead to a better management of cognitive impairment and their consequences on CKD management.

[Assessment and impairment of cognitive functions]

Cognitive functions enable us to receive, select, store, transform, process and retrieve the information we receive from the outside world. These functions are controlled by different brain structures that interact with each other, enabling us to interact with and understand the world around us. In the course of aging or the onset of neurocognitive diseases, these functions may be impaired to a greater or lesser extent, giving rise to a considerable variety of neurocognitive impairment profiles. When a patient appears to be suffering from neurocognitive disorders, a thorough neuropsychological evaluation can help to characterize this impairment precisely, before guiding therapeutic management. It also contributes significantly to the etiological diagnosis of the disorder.

[Presbyphagia and swallowing disorders]

Swallowing disorders, which are frequent in geriatrics, are linked to multiple pathologies: cancer, stroke, neurocognitive disorders, acute confusion, vigilance disorders, etc. They can have serious consequences and therefore require special care. From the identification of the disorders by the doctor, the nurse, the caregiver, to the speech therapy assessment, through the adaptation of the diet by the dietician, the management of swallowing disorders concerns all the medical and paramedical staff. The aim of this article is to present the main existing recommendations to promote the patient's feeding despite the presence of these disorders.

Cognitive performance is associated with glomerular filtration rate in patients with chronic kidney disease: results from the CKD-REIN cohort

BACKGROUND

Chronic kidney disease (CKD) is associated with cognitive impairment in general population. We assessed the association between kidney and cognitive functions in patients with CKD and the influence of cardiovascular (CV) risk factors, and depression on this association.

METHODS

The CKD-Renal Epidemiology and Information Network cohort included 3033 patients with CKD stages 3-4, followed for 5 years. Cognitive function was assessed with the Mini-Mental State Examination (MMSE) and estimated glomerular filtration rate (eGFR) with the CKD-Epidemiology Collaboration equation-creatinin formula. Evolution of the MMSE score over time and its association with baseline eGFR were investigated with linear mixed models. We assessed the risk of incident cognitive outcome (hospitalisation or death with relevant International Classification of Disease-10 codes), with a Cox proportional hazard model.

RESULTS

The mean age was 66.8, the mean eGFR was 33 mL/min/1.73 m² and 387 patients (13.0%) had an MMSE score below 24 at baseline. A 10 mL/min/1.73 m² decrement of baseline eGFR was associated with a mean MMSE decrease of 0.12 (95% CI 0.04 to 0.19) after adjustment for demographic characteristics, depression, CV risk factors and disease; but baseline eGFR was not associated with MMSE temporal evolution. HR for cognitive outcome during follow-up (median 2.01 years) associated with a 10 mL/min/1.73 m² decrement of baseline eGFR was 1.35 (1.07, 1.70) (p=0.01) after adjustment.

CONCLUSIONS

In patients with CKD, lower eGFR was associated with worse cognitive performance and incident cognitive events, independently of demographics, CV risk factors and depression.

TRIAL REGISTRATION NUMBER

NCT03381950.

MO503: Cognitive Performance in Patients With Chronic Kidney Disease: Results From the CKD-Rein Cohort Study

BACKGROUND AND AIMS

Chronic kidney disease (CKD) is a risk factor for cognitive impairment. In the general population, many risk factors have been reported in association with incident major neurocognitive disorders. The link between CKD and cognitive dysfunction is not completely understood; it may involve different mechanisms such as vascular dysfunction or uremic toxin toxicity. We aimed to assess the influence of cardiovascular risk factors, cardiovascular disease and depression on the association between kidney function and cognitive function in patients with CKD.

METHOD

We analyzed baseline data from 3033 patients with CKD stage 3–5 included in the Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort between 2013 and 2016. Cognitive function was assessed with the Mini Mental State Examination (MMSE), and the glomerular filtration rate was estimated with the CKD EPI formula. We applied unadjusted and adjusted linear and logistic regression models, with the MMSE score as a continuous or categorical variable (at a cut-off point at 24/30).

RESULTS

The mean patient age was 66.8, the mean estimated glomerular filtration rate (eGFR) was 33 mL/min/1.73 m2 and 393 patients (13.0%) had a MMSE score &lt;24. We observed that, relative to patients with an MMSE score of 24 or more, patients with a score &lt;24 were older and more likely to be female and dependent on activities of daily living (ADL) and/or instrumental ADL. They were taking more medications and they were more affected by depressive symptoms as measured by the CES-D-10 (10 item Centre for Epidemiological Studies-Depression scale). Patients with a score &lt;24 were also more likely to present cardiovascular (CV) risk factors and CV comorbidities. They had a significantly higher parathyroid hormone level, lower haemoglobin, lower albumin and lower eGFR.

The eGFR was positively associated with the MMSE score before and after adjustment for age, sex, education level, cardiovascular risk factors, cardiovascular disease and depression, giving point increases in the MMSE score of 0.24 (0.15–0.33; P &lt; .001) and 0.14 (0.04–0.23; P = .006) for a 10 mL/min/1.73 m2 increment in the eGFR, respectively. Other risk factors significantly associated with a lower MMSE score in multivariate analysis were age, female sex, lower educational level, diabetes, obesity, cerebrovascular disease, atrial fibrillation and CES-D-10 score. The eGFR was associated with a low MMSE score (defined as MMSE score &lt;24/30) with a crude odds ratio (OR) of 0.82 (0.75–0.90), which remained significant at 0.88 (0.78–0.98) after adjustment for age, sex, educational level, cardiovascular risk factors (hypertension, diabetes mellitus, dyslipidaemia, obesity and smoking), cardiovascular comorbidities (cerebrovascular disease, atrial fibrillation and heart failure), history of depression, laboratory parameters (haemoglobin and phosphate) and CES-D score (after imputation of missing values).

CONCLUSION

In a cohort of well-phenotyped patients with CKD, lower eGFR is associated with worse cognitive function, independent of age, sex, educational level, cardiovascular injury and depression.

[Phasic disorders and aphasia in geriatrics]

Aphasia, resulting from a brain lesion, leads to a partial or total loss of language in the elderly. By affecting communication abilities, it has repercussions on the life of the subject and his family. There are two types of aphasia. The roles of the caregiver and the speech therapist are in all cases essential. Depending on the communication difficulties encountered by the patient, specific supports can be recommended.

[Lipid pneumonitis, a serious iatrogenic event with lubricating laxatives]

The prescription of lubricating laxatives (paraffin oil) is widespread in geriatrics because of the frequency of constipation. These molecules can cause serious adverse effects such as lipoid pneumonia, especially in subjects with swallowing disorders.

[Colorectal cancer and preoperative geriatric assessment]

With the ageing of the population and the increase in the incidence of cancer in the population over 75 years of age, a partnership between geriatricians and oncologists is becoming necessary to optimise the management of these patients. There is great variability in the profiles of elderly patients and age cannot be the only criterion of the decision making. Thus, it is necessary to identify patients who will benefit from an in-depth geriatric assessment (IGA) and the G8 screening tool used in oncology consultations allows to do so. The EGA offers a multidisciplinary approach to functional, psychological, nutritional, cognitive and social status of the person, and has been shown to have prognostic value for survival and relevance in guiding treatment choices.

[Oncogeriatric assessment: The first step in personalizing cancer treatment in the elderly]

With aging worldwide population and the high incidence of cancer in the population of people over 75 years old, there is a need for oncologists and geriatricians to strengthen their collaboration to improve elderly patients care. Complexity of cancer and aging issues must be considered simultaneously to establish a personalized care plan. Thus, the G8 is a screening tool that allows to identify patients who should benefit from a geriatric assessment, which is a key step in the management process. This specific evaluation offers a multidisciplinary approach to functional, psychological, nutritional, cognitive and social status and has demonstrated its prognostic value in terms of choice of treatment but also in terms of patient survival. In nearly 20% of cases, the geriatric assessment leads to a change in the choice of treatment, and at one year the initial care plan is not carried out in a quarter of cases. The presence of malnutrition and functional impairment leading to dependence on basic activities of daily living had a significant impact on this change in therapeutic choice. Survival is not only impacted by malnutrition and functional impairment but also by the presence of severe comorbidities and thymic and neurocognitive impairment. The patient's choice must remain at the center of the elaboration of the care plan with the oncologists and geriatricians in order to propose the most appropriate treatment for his or her situation.