Chapter 56. Aging & Renal Disease

As the elderly population continues to grow, the diagnosis and treatment of renal diseases become challenges for the everyday nephrology practice. Although elderly patients are prone to the same diseases of the kidney as younger patients, the diagnostic criteria are not so clearly defined. Anatomic and functional age-induced changes often overlap pathologic processes. The resulting reduced renal function decreases the individual's capacity to respond to a variety of stresses and has important clinical implications for diagnosis and treatment. Comorbid conditions, the absence of classic symptoms, “symptomless” conditions in those with impaired consciousness, and the poor correlation between clinical presentation and the etiology of disease make the diagnosis of renal diseases in the elderly even more difficult. Finally, several pathologic conditions of the kidneys might occur simultaneously in the elderly.

General Considerations

Acute renal failure (ARF) is more frequent in elderly patients than in younger patients and it is often due to multiple causes. Predisposing factors are age-related changes in renal structure and function. The incidence of ARF is estimated to involve 6–10% of all admissions of the elderly to an acute medical service.

Pathogenesis

The most frequent causes of ARF are nephrotoxic drugs, sepsis, and hypoperfusion. Radiocontrast-induced ARF and postoperative ARF are still very frequent (occurring in about 17% and 25% of cases, respectively).

Clinical Findings

About 50% of the patients with ARF have a prerenal etiology and the majority of them have only mild renal impairment. Oliguria is not a prominent finding in ARF in the elderly and cases of nonoliguric ARF may go unrecognized. This may result in overdosing patients with renally excreted medications (digitalis, gentamicin). Hypophosphatemia and hypokalemia, when present, most probably reflect the severity of the underlying disease or malnutrition.

Treatment

The treatment of patients with ARF requires careful monitoring of fluid and electrolyte balance. It is very important to prevent malnutrition since hypercatabolism is a frequent finding in elderly patients with ARF; nutritional support should be implemented during the early phase since such patients may lose about 0.5 kg of body mass per day. On the other hand, fluid restriction will delay recovery from ARF and lead to a deterioration in central nervous system function. In patients with advanced renal failure standard dialytic techniques including slow continuous methods should be applied.

Prognosis

The prognosis differs depending on the underlying disease since age itself does not have a significant impact on the prognosis of patients with ARF. The aged kidney retains the capacity to recover from acute ischemic or toxic injury over several weeks. However, care should be taken to avoid nephrotoxins, radiocontrast agents, and volume depletion. The overall mortality rates correlate with the severity of clinical disease ranging between 40% and 60%. Aortic aneurysm repair had very high mortality (as high as 100% in some series) but recent introduction of endovascular repair has decreased this substantially. Other causes of acute renal failure such as hepatic failure, shock, and renovascular disease also have high mortality. Patients with intrinsic renal failure had a higher than expected mortality rate possibly because of delays in diagnosis. A higher mortality rate was also seen in obstructive uropathy in the elderly, which is caused by malignant diseases more often than in younger patients. The prognosis is negatively influenced by malnutrition and high urea and creatinine levels. Of those patients who survive to discharge, about 60% have complete recovery of renal function and the remaining have some degree of renal impairment not requiring dialysis.

General Considerations

Glomerular diseases have a similar or slightly higher incidence in the elderly than in younger adults. The disease spectrum is similar to that in younger populations with the main presenting features being proteinuria and hematuria.

Renal biopsy, as a diagnostic marker, remains the gold standard for diagnosis, with no significant increase in complication rates as compared to younger patients. Still, some age-related differences exist with regard to difficulties in distinguishing lesions of chronic ischemia from previous proliferative glomerulonephritis (GN) and focal sclerosing GN. Elderly patients who undergo renal biopsy have a greater incidence of nephrotic syndrome or acute renal failure than younger patients: Idiopathic GN is the most common underlying diagnosis followed by secondary GN and unclassified GN.

Nephrotic Syndrome

General Considerations

Nephrotic syndrome is the most common reason for renal biopsy in the elderly. The underlying reasons include membranous nephropathy (an almost three times higher incidence than in the overall population), minimal change disease (MCD), amyloidosis, and multiple myeloma. Focal segmental glomerulosclerosis and immunoglobulin A (IgA) nephropathy are less common than in younger patients.

Membranous Nephropathy

General Considerations

Out of all cases of membranous nephropathy in the elderly, about 80% are idiopathic and 20% are secondary to solid organ tumors and drugs.

Clinical Findings

A full clinical examination, chest x-ray, CT scan of the abdomen, and stool examination should be performed as screening tests. Apart from nephrotic proteinuria, which is a usual finding, elderly patients have hypertension, hematuria, and renal impairment at the time of biopsy more frequently than younger patients.

Treatment

Treatment with prednisone and chlorambucil has a favorable effect, but remission rates were lower, the time to remission was longer, and the severity of side effects was higher. The recommended dose of chlorambucil is 0.1 mg/kg/day for 3–6 months with or without low-dose corticosteroids.

Minimal Change Nephropathy

General Considerations

The typical presentation of minimal change nephropathy (MCN) in elderly patients is nephritic syndrome. Again, microscopic hematuria, hypertension, and renal impairment are more frequent at the time of presentation than in younger patients.

Complications

Complications resulting from hypoalbuminemia, hyperlipidemia, and hypercoagulability include thrombotic events, infections, and progressive cardiovascular disease.

Treatment

Treatment with a standard immunosuppressive regimen can be used, but for a longer duration than in younger patients. Corticosteroid-resistant patients may benefit from chlorambucil, cyclophosphamide, or cyclosporine A, but with a risk of bone marrow depression.

Focal Segmental Glomerulosclerosis

General Considerations

This is not the usual form of glomerulonephritis in the elderly.

Clinical Findings

Heavy proteinuria is a typical presentation of disease, which is often associated with some degree of renal impairment.

Treatment

A trial of corticosteroids for 3 months (or even an additional 3 months if there is no response) should be considered. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) have an antiproteinuric effect and should be used either before trial of steroids or simultaneously with steroids.

Proliferative Glomerulonephritis

General Considerations

Immune complex deposition, antineutrophylic cytoplasmic antibody (ANCA), and antiglomerular basement membrane (anti-GBM) antibodies may cause proliferative GN with the clinical findings and course of disease similar to those found in younger patients. Elderly patients tend to present with much higher serum creatinine levels and a higher incidence of hypertension and refractory renal impairment. Standard immunosuppressive therapy in elderly patients appears to be as effective as in younger patients in terms of short-term prognosis, but there is a higher risk of complications with immunosuppression.

Clinical Findings

Crescentic GN can be associated with immune deposits (as seen in severe IgA nephropathy or lupus nephritis) or with pauci-immune disease without immune deposits (Wegener's granulomatosis, anti-GBM disease, and polyarteritis nodosa). The clinical presentation includes nausea, anorexia, malaise, edema, arthralgia, and myalgia. Symptoms of pyrexia, rash, and hemoptysis suggest a diagnosis of vasculitis. Renal manifestations include hematuria (microscopic or macroscopic), hypertension, and oliguria. Serum ANCA levels, anti-GBM levels, antinuclear factor, complement, immunoglobulin levels, and renal biopsy help distinguishing the different syndromes.

Treatment

A standard immunosuppressive regimen with steroids and cyclophosphamide is indicated.

Systemic Disorders Causing Glomerular Diseases

General Considerations

As in the overall population, glomerular diseases are associated with diabetes, myeloma, systemic lupus erythematosus, and systemic bacterial infections and no specific findings for elderly patients have been described compared to younger patients.

Clinical Findings

Acute poststreptococcal glomerulonephritis (APSGN) originates more often from pyodermal than from throat infection. Therefore antideoxyribonuclease B is a more specific test than antistreptolysin O titer in elderly patients with APSGN. Oliguria is a more frequent finding most probably because of underlying age-related renal changes. The outcome of disease is similar to that in younger patients and most patients recover renal function.

Ischemic Nephropathy

General Considerations

Ischemic nephropathy (or insufficient renal perfusion) includes two entities: Renal macrovascular disease or renal artery stenosis (RAS) and microvascular diseases, which affect intrarenal arteries.

The prevalence of RAS is difficult to estimate, but according to some data age is a significant multivariate predictor for RAS (>50%). The prevalence of significant RAS is ∼50% in hypertensive patients >55 years of age who have coexistent coronary artery disease (CAD) or peripheral vascular disease (PVD). The risk factors include age, hypertension, diabetes, and evidence of vascular disease elsewhere in the body.

Clinical Findings

Symptoms and Signs

Disease should be suspected in patients who have flash pulmonary edema, unresponsive hypertension, and generalized vascular disease, in those who develop ARF after mild hypotension or with use of ACEIs or ARBs, and in cases of renal impairment of unknown etiology.

Imaging Studies

Diagnostic procedures include duplex ultrasonography, captopril renal scintigraphy, and magnetic resonance (MR) and computed tomographic (CT) angiography using the gold standard of intra-arterial angiography.

Complications

The disease is often undetected and if left untreated stenosis will progress over a few years.

Treatment

Therapy includes angioplasty, angioplasty with stenting, and surgery. The initial success of angioplasty is high (90–95%), but restenosis occurs in up to 25% of patients. Stents inserted into the renal arteries have improved long-term results. Surgical procedures include aortorenal bypass, transaortic renal endarterectomy, hepatorenal or gastroduodenal renal bypass (for right-side stenosis), splenorenal bypass (for left-side stenosis), extraanatomic revascularization, and autotransplantation. Even though results with surgery are very good, the treatment is not always recommended due to the progressive decline in renal function even after successful revascularization.

Microvascular disease of the kidney has not been extensively studied and it is suggested to be a cause of many cases of end-stage renal disease (ESRD) of “unknown etiology.”

Atheroembolic Disease

General Considerations

Atheroembolic disease may be a consequence of myocardial infarction, atrial fibrillation, subacute bacterial endocarditis, extensive surgery, and angiography. Although uncommon, it may cause both acute and chronic renal failure.

Clinical Findings

Clinical finding may be absent or include severe flank pain and tenderness, hematuria, pyrexia, renal failure, and hypertension. In case of cholesterol embolism, patients may experience a sudden increase in serum creatinine, signs of peripheral embolism in the limbs, confusional state, gut ischemia, and peripheral eosinophilia after arterial catheterization or systemic heparinization. Small emboli are difficult to diagnose; major emboli are defined by pyelography, renal scan, and aortography. Cholesterol embolism is confirmed by renal biopsy (intravascular cholesterol crystals) and skin or muscle biopsy.

Treatment

Therapy includes thrombolytic agents given intraarterially. The final renal function depends on the collateral renal blood flow.

Diabetic Nephropathy

General Considerations

Type 2 diabetes is more common in the elderly and diabetic nephropathy is a frequent finding at the time of diagnosis. Therefore, the National Kidney Foundation recommends that patients aged 70 years or older with non-insulin-dependent diabetes mellitus should test their urine for microalbuminuria (albumin excretion of 30–300 mg/24 hours in at least two urine samples within 6–12 weeks). Apart from glycemic control, progression of nephropathy is influenced by two independent risk factors: hypertension and diabetic dyslipidemia.

Treatment

Strict glycemic control, reduction of blood pressure to less than 130/80 mm Hg, and introduction of ACEIs and/or angiotensin II receptor blockers (independently of blood pressure) are advised if microalbuminuria or proteinuria is present. The antihypertensive protocol recommended by the National Kidney Foundation Hypertension and Diabetes Working Group suggests a combination of ACEIs and diuretics as initial therapy. If the resting pulse rate exceeds 84/minute or in case of coexisting cardiac disease, β-blockers may be introduced in combination with ACEIs and/or angiotensin II receptor blockers. Special attention should be paid to subclinical RAS in elderly patients with close monitoring of serum creatinine. A self-limited decline in renal function of up to 30% within the first 4 months is acceptable if the baseline serum creatinine is less than 250 μmol/L. Even in that case, there is continued benefit after 3 years of therapy. Although dyslipidemia has been considered a risk factor for disease progression, there are no clear data indicating that lipid-lowering agents reduce the rate of progression.

Multiple Myeloma

General Considerations

Multiple myeloma is more frequent in older than in younger people. Renal failure is a consequence of myeloma glomerulopathy, tubular toxic effects of light chains, cast formation and intratubular obstruction, hypercalcemia, hyperuricemia, and cryoglobulinemia. Contributing factors are dehydration and nephrotoxic drugs.

Treatment

Management usually involves chemotherapy with renal support. Hyperuricemia and hypercalcemia secondary to chemotherapy should be avoided by adequate hydration and the use of allopurinol.

Prognosis

The prognosis depends on a variety of paraproteins, the stage of myeloma, and the type of chemotherapy. Biopsy may help predict prognosis; light chain deposits have the best prognosis. A good survival of myeloma patients on dialysis has been reported. Peritoneal dialysis has been recommended as the treatment of choice due to a better clearance of immunoglobulins, a reduction in the tubular toxic effect of the light chains, and a reduced incidence of hyperviscosity syndrome.

The most common cause of urinary obstruction in old age is benign prostatic hypertrophy; age does not have a major effect on the prevalence or clinical presentation of nephrolithiasis and renal tumors. The increased intrapelvic pressure caused by a urinary obstruction is being transmitted back through the tubular lumina and induces atrophy of the renal parenchyma. After prostatectomy, renal plasma flow increases slightly, but glomerular filtration does not change in most of the cases.

Urinary Tract Infections in the Elderly

General Considerations

Predisposing factors for urinary tract infections in the elderly include structural and functional abnormalities of the urinary tract, comorbidity, invasive instrumentation/operations, and bacterial virulence. The most common causes of obstruction are benign prostatic hypertrophy, carcinoma, changes of the bladder neck, malformations, nephrolithiasis and ureterolithiasis, and uterine prolapse and descensus of the vagina in females. The most important functional impairments are due to diabetes, stroke, Parkinson's disease, motor neuron disease, and spinal injury.

Prevention

An important factor for urinary tract infection in the elderly is the use of indwelling catheters. If a catheter is left in situ for longer periods of time, there is a risk of developing polymicrobial bacteriuria or chronic pyelonephritis. Therefore, removal of the catheter is recommended at the earliest time. Older patients are more susceptible to the consequences of instrumentation and surgical operations involving genitourinary tract.

Clinical Findings

Bacterial virulence factors affect the ability of an organism to attach to human uroepithelial cells and are related to the severity of infection. These factors include fimbria, which increase the attachment of the organism to cells (P and S fimbriae), toxins secreted by the organisms (α-hemolysin, cytotoxic necrotizing factor-1, enterobactin), and proteins that allow the organism to alter complement activation. These virulence factors are modulated by genes triggered by signals such as temperature, pH, and the oxygen level of the tissues.

Treatment

A short-term course of antibiotic therapy for those manifesting significant bacteriuria for the first time is indicated regardless of symptoms. Although therapy does not protect against renal damage, it is helpful in mitigating distressing symptoms.

Cotrimaxazole or amoxicillin is recommended for uncomplicated urinary tract infections. Penicillin and aminoglycoside or quinolone therapy are the therapies of choice for catheter-associated infections.

Acute pyelonephritis is treated with intravenous antibiotics with ampicillin and an aminoglycoside or a third-generation cephalosporin or a quinolone. At the same time, an evaluation for reversible causes should be done (obstruction, nephrolithiasis, cysts, neoplasia).

Bacteriuria in the Elderly

General Considerations

The risk of bacteriuria increases with age. Older, sicker, and less mobile patients are more susceptible to urinary infection and this reflects a general condition rather than a causal relationship.

Clinical Findings

Significant bacteriuria occurs in up to 20% of the population aged 65 years and over. The incidence of bacteriuria increases more in intermittently catheterized hospitalized patients (about 50%) than in noncatheterized ones (about 43%). The commonest microorganisms seen in urine culture in uncomplicated infections are Escherichia coli, Klebsiella spp., Staphylococcus saprophyticus, Enterococcus spp., and Proteus spp. Pseudomonas and Candida spp. are more frequent in catheterized patients. No long-term sequelae of bacteriuria are seen in the elderly. The relationship among bacteriuria, lower urinary tract infection, and upper urinary tract infection in the elderly is not clear.

Asymptomatic bacteriuria is defined as ≥100,000 colony-forming units/mL urine on two or more consecutive occasions without any clinical symptoms. The prevalence of asymptomatic bacteriuria increases with age and functional debility. It is estimated at 9.3% in women aged 65 years or more, increasing to 20–50% in women over 80 years. Of men over 80 years 6–20% may have asymptomatic bacteriuria. Screening for bacteriuria is not recommended unless patients have some indicators of infection (incontinence, frequency, dysuria). In the elderly, a leukocyte count above 10 cells/mm3 in the urinary sediment does not correlate with infection and therefore it should not be used as a valid diagnostic marker.

Treatment

Treatment for 2 weeks is recommended only in those with previous frequent urinary tract infections, in patients who have a structural defect in their urinary tract, and in those with a history of renal transplantation and prior to a urologic procedure. Urine bacteriology should be rechecked 4 weeks after the discontinuation of treatment.

Pyelonephritis

General Considerations

Autopsy data revealed that the prevalence of pyelonephritis in the elderly ranges from 20% to 28%. Infections with fastidious organisms are more frequent (Lactobacilli, Ureaplasma urealyticum, Gardnerella vaginalis, Staphylococcus saphrophyticus, Corynebacterium spp., and certain strains of Streptococcus spp.) than in younger people. An important feature of chronic pyelonephritis is that older patients have an asymptomatic course of disease; it is clinically diagnosed in only about 20% of those patients detected at autopsy. In addition, many cases are diagnosed accidentally during admission into a hospital for other reasons or even at advanced stages including uremia. Postinfectious inflammatory mechanisms may induce prolonged damage in the renal interstitium after the disappearance of bacteria from the tissue.

Allergic Interstitial Nephritis

General Considerations

The elderly are very often subject to polypharmacy and medications are a common cause of renal disease. The most frequent drugs causing allergic interstitial nephritis are antibiotics (penicillin and sulfonamides), analgesics, anti-inflammatory drugs, anticoagulants, diuretics, anticonvulsants, allopurinol, metals (lithium), and immunosuppressive drugs (azathioprine).

Clinical Findings

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce renal failure by interference with prostaglandin release and by inducing acute or chronic allergic interstitial nephritis usually without classic symptoms of allergy or eosinophilia.

Treatment

Withdrawal of the drug is usually sufficient treatment and steroid therapy is rarely required.

Radiocontrast Nephrotoxicity

General Considerations

Age itself is not a risk factor for the nephrotoxic effect of radiocontrast materials. However, predisposing factors for radiocontrast nephrotoxicity are more frequent in the elderly and include subclinical renal disease, diabetes, congestive heart failure, and dehydration. The volume of contrast used and the use of nonionic contrast of high osmolality are two additional factors that may stress nephrotoxicity.

Prevention

Nephrotoxicity may be prevented by proper hydration with saline or hypotonic saline for a minimum of 12 hours and oral N-acetylcysteine (600 mg orally twice daily on the day before and on the day of administration of the contrast agent).

Clinical Findings

Radiocontrast agents cause vacuolization of the cells in the proximal tubule possibly by intense local vasoconstriction, which may damage the kidneys of high-risk elderly patients.

The use of carbon dioxide as a contrast and fenoldopan (a dopamine agonist) at the time of the procedure decreases the prevalence of nephrotoxicity. There are no clear data indicating that the use of mannitol, furosemide, or renal vasodilator agents during the procedure may improve the outcome.

Renal Papillary Necrosis

General Considerations

Renal papillary necrosis is ischemic necrosis of the papillae and the medullary pyramid. It is most commonly a complication of the severe form of chronic pyelonephritis, unilateral renal artery stenosis, and prolonged consumption of analgesics, especially phenacetin.

Clinical Findings

The patient usually has hematuria, renal colic, and often a high fever.

Treatment

In the majority of cases relief of the obstruction caused by necrotic papilla leads to improved renal function. The disease has a rapid course toward uremia and, if untreated, death.

General Considerations

The number of elderly patients who need renal replacement therapy (RRT) for ESRD grows steadily coincident with the overall aging of the population and with the increasing frequency with which elderly patients are accepted for such treatment. The most rapid growth among all new ESRD patients is in those who are 65–74 years of age. Individual countries show a marked variation in their trends in the use of RRT, possibly reflecting the variability in the accessibility to health care worldwide.

Elderly patients are less likely than younger patients to have ESRD secondary to GN (except in Japan where the number of elderly patients with GN is increasing) but are more likely to have renal failure due to type 2 diabetes and/or hypertension and to renal vascular disease. Such patients have many comorbid conditions that make therapy considerably more difficult and require multidisciplinary work and special knowledge of geriatric medicine.

Experience with elderly patients with renal diseases and uremia is still limited. For ethical reasons, there are very few comparative studies and no randomized, prospective studies have been conducted. In addition, these studies are based on populations that differ considerably in both medical and social characteristics.

Treatment

Predialysis Management and Initiation of Dialysis

In elderly patients, chronic renal failure is characterized by an absence of classic symptoms, the nonspecific nature of the presenting symptoms, the presence of comorbid conditions, and by interference with the interpretation of findings by the aging process. Therefore these patients require regular screening for comorbid conditions, screening for cancer [prostate-specific antigen (PSA), Pap smear, mammography, renal ultrasound or CT, X-ray], review of medications with an emphasis on over-the-counter drugs, the possibility of drug interactions, dosing, adequate vaccination, examination of feet, especially in diabetics, and, if necessary, psychiatric and social intervention.

The elderly show a poor correlation between serum creatinine and glomerular filtration rate and therefore it is preferable to monitor creatinine clearance measured or calculated from serum creatinine. Salt intake should be limited to 4–5 g/L/day and regular clinical monitoring of fluid overload and/or dehydration is advisable. Severe constipation, which is frequent in the elderly, may exacerbate hyperkalemia. In the predialysis phase [chronic kidney disease (CKD) stages 3–4], the use of recombinant human erythropoietin (rh-EPO) may improve the quality of life (QOL) and prevent left ventricular hypertrophy. Strict dietary protein restriction is often unnecessary (acceptable ingestion: 60–70 g protein/day). Also, to avoid acidosis, special attention should be paid to serum bicarbonate levels.

Late referral to a nephrology unit is significantly related to early death. On some occasions, it is not that the elderly are not referred early, but that the nephrologist may have delayed initiation of dialysis due to misleading serum creatinine levels. Therefore, the National Kidney Foundation Disease Outcomes Quality Initiative (NKF-DOQI) guidelines suggest that regular estimations of weekly creatinine clearance to avoid late initiation of dialysis should be performed. An early referral may provide better salt and water balance and better control of anemia, leading to a decrease in overall morbidity and mortality. Initiation of dialysis should be recommended before uremic symptoms become overt and particularly before there is evidence of malnutrition. A low serum albumin level, a dietary protein intake <0.7 g/kg/day, weight loss, and a decrease in muscle mass indicate the need for dialysis.

Chronic Hemodialysis

In most countries hospital hemodialysis, which is the principal form of RRT in the elderly, offers many advantages. Dialysis is performed by nurses, the treatment time is shorter, it allows for socialization with staff and other patients, and there is continuous follow-up by the medical team.

Crucial to successful hemodialysis is the presence of a functional vascular access. Proper planning for such an access requires comprehensive evaluation with respect to earlier placement of vascular catheters, the presence of a cardiac pacemaker on a prosthetic cardiac valve, the presence of enlarged axillary lymph nodes, and past radiation therapy. Diabetes and hypertension, the most frequent causes of ESRD in the elderly, are associated with abnormal blood vessels. A good forearm Brescia–Cimino arteriovenous fistula is the ideal form of vascular access whatever the patient's age. However, there is a higher primary failure rate and shorter survival with this form of access in the elderly. Among the various vascular substitutes, the homologous saphenous vein graft proved to be superior to other synthetic grafts. In some elderly patients, particularly those with diabetes, synthetic grafts can be very useful. Vascular-access thrombosis associated with rh-EPO therapy was more common in elderly patients for both native arteriovenous fistulas and grafts. In cases of late referral, “trial dialysis,” and a failed arteriovenous fistula, both cuffed and noncuffed catheters may provide suitable vascular access.

Hemodialysis is more likely to precipitate cardiovascular instability in the elderly. Some investigators reported more frequent episodes of hypotension during dialysis and/or postdialysis, which may be a risk factor for falls. In elderly patients who have autonomic dysfunction and a low cardiac reserve, hypotension during hemodialysis may be a consequence of rapid ultrafiltration. Also, the incidence of arrhythmias increases progressively with age and in such patients arrhythmias could be a risk factor for cardiac death. While on hemodialysis, elderly patients may develop gastrointestinal bleeding due to gastritis, duodenal ulceration, and angiodysplasia.

Although it is rarely used, home dialysis is a highly successful therapeutic option. Individuals on home hemodialysis have few dialysis-related complications.

Chronic Peritoneal Dialysis

Chronic peritoneal dialysis (CPD) offers many advantages including good control of hypertension, independence from hospitals, simplicity of access, better cardiovascular stability (less hypotension and fewer arrhythmias), and slow solute removal. A family member may perform such dialysis and the patient does not need to go to the hospital three times a week. On the other hand, patients are at higher risk of complications such as malnutrition, which is more frequent in the elderly than in younger peritoneal dialysis (PD) patients and which is highly correlated with mortality. In addition, low initial albumin levels correlate with mortality among elderly patients on continuous ambulatory peritoneal dialysis (CAPD) and cachexia is a frequent cause of death.

Elderly patients with uremia have an increased risk of infection because they suffer from immunodeficiency, malnutrition, and high rates of bowel disease, which may explain the higher rates of peritonitis among the elderly on PD. Bedridden patients tend to have an even higher rate of peritonitis. Catheter-related complications are infrequent among elderly patients on PD, probably because they are less active than younger patients. The higher incidence of hernias (incisional, inguinal) in elderly PD patients has been attributed to weakness of the abdominal wall.

Hospitalization rates are higher among elderly than among younger patients, especially among those of African descent and diabetics. The duration of stay varies between 5.5 and 23.1 in-hospital days.

PD is not used extensively among the elderly because they are unable to perform dialysis by themselves; about 61.2% of very old patients (above 80 years) need help with dialysis exchanges, exit-site care, and medication. Many patients older than 65 years suffer from comorbid conditions such as depression, dementia, impaired vision, and decreased physical and mental activity, all of which significantly impair self-performance of PD. However, given a network of medical, nursing, and social support, the elderly can perform PD (especially automated PD) successfully at home.

Renal Transplantation

Renal transplantation may be successful in the elderly; perioperative survival is comparable to that among younger recipients. However, in Europe, only 2% of patients older than 65 years and less than 0.3% of patients older than 75 years receive renal transplants, except in Norway, where transplantation is the primary mode of therapy for patients 60–65 years old. Lower transplantation rates among the elderly may be explained not only by selection bias but also by a shortage of organ donation; older patients tend to have fewer living donors and younger persons are less willing to donate a kidney to an older relative than to a younger one. The shortage of kidneys could be improved in older recipients by using kidneys from older cadaveric donors. Kidneys from elderly donors may be suitable for elderly recipients who have lower muscle mass and less metabolic demands coupled with decreased immunologic reactivity, thus allowing the use of less aggressive immunosuppressive regimens without increasing rejection rates. However, special attention should be paid to age and size matching between donor and recipient and to cold ischemia time, which should be as short as possible. No differences in kidney survival were found in a comparison of elderly patients previously treated by hemodialysis or CAPD. Over the past 10 years the improvement in overall patient and graft survival rates may be related to increased experience with the use of newer immunosuppressive regimes [United States Renal Data System (USRDS), Canadian Organ Replacement Register (CORR)] in the elderly.

Social Issues

With the growing number of elderly patients requiring dialysis, an increasing number need assisted care.

Home-Care Nursing

Trained home-care nurses may provide the elderly with comfortable and safe home dialysis without reliance on family members. Also, the low rate of infection and hospitalization and the avoidance of transportation in this high-risk population achieve significant savings. The rates of peritonitis and exit-site infection are not significantly different between those who had assisted dialysis by a home-care nurse and those on self-dialysis. The home-care nurse may assist in the treatment of episodes of peritonitis and other complications, thereby contributing to a lower total hospitalization rate.

Rehabilitation and Chronic Care Dialysis Units

Rehabilitation and chronic care dialysis units (RCDUs) may provide dialysis, physiotherapy, a rehabilitation program, and occupational therapy for those patients who cannot return home or who cannot be placed in a nursing home. Such units achieve significant reduction in costs compared to hospital treatment and this cost reduction is not accompanied by any deterioration in the elderly person's QOL.

Dialysis in the Nursing Home

An increasing number of the elderly will live in a nursing home in the future. A substantial number of nursing homes still refuse to introduce dialysis into everyday care because they believe that the ESRD elderly population is difficult to care for, because they lack knowledge about dialysis and renal diet and lack adequate storage space for machines and supplies, and because there is poor communication with the renal team.

Although hemodialysis is the mode most used in nursing homes, published data are limited and, until now, there have been no control trials. Nursing home residents on hemodialysis spend about 15 hours in the dialysis unit per week; this coupled with transportation time takes time away from rehabilitation and social activities. The need for transportation may be overcome by building the dialysis center within or adjacent to a skilled nursing facility.

PD in nursing homes offers many advantages and allows flexibility in schedules for patients and for staff. In this regard, automated PD (APD) or nightly PD frees the patients' daytime for nursing home activities, increases socialization, and results in better rehabilitation, which improves their QOL. Patients on PD in nursing homes and day care centers have a lower survival rate than the general CAPD population. This is probably a reflection of patient selection because patients in nursing homes are significantly older and have many comorbid conditions. It seems that rates of peritonitis do not differ significantly from those in the overall noninstitutionalized elderly.

Ethical Issues

Dialysis in the elderly is a life-extending treatment, and, for many, these are lives of quality. However, some older individuals elect to cease dialysis because of QOL issues. For this reason, health care professionals should be completely honest when educating patients and their families regarding the burdens associated with living on dialysis. They cannot make this decision for others but should share their knowledge and experience and advise patients without projecting their own prejudices. With respect to the decision-making process, the first published guidelines that appeared in 1993 were personal and did not reflect the opinion of the majority. A set of consensus guidelines, published by the NKF in 1996, allowed all patients to explore their own options. Finally, the American Society of Nephrology and the Renal Physicians Association published evidence-based guidelines in 2000. All of these publications emphasize that they are just guidelines and not rules; they also emphasize the difficulties of the decision-making process arising from the heterogeneous nature of both providers and the patient population. None of the guidelines recommend mandatory standards for the determination of the patient's candidacy for dialysis.

Sometimes neither the medical team nor the patient or family members find it easy to reach a decision. In that case, the patient should be offered a period of trial dialysis, say for of 30–90 days. All guidelines recommend that dialysis not be offered to patients with a known serious terminal illness or patients who have serious mental impairment as a result of stroke, Alzheimer's disease, or neurologic dysfunction. Also, patients on dialysis who develop a terminal illness or become demented should be offered the option of discontinuing dialysis. Patients choosing to withdraw from dialysis should know that they will receive ongoing active, caring treatment to minimize suffering and prevent pain.

Withdrawal from dialysis is more frequent among elderly patients, particularly among those living in a nursing home. However, this high discontinuation rate among elderly patients is not due to dialysis per se but rather to associated social and medical circumstances.