Special Considerations for Dialysis in the Elderly

Dialysis planning for the elderly: for whom, and when?

One of the areas in the field of nephrology with the greatest opportunity to improve the management of patients is the time of dialysis initiation. To improve the early outcomes of ESRD patients, it is often recommended that dialysis planning begin when the eGFR decreases to <30 mL/min/1.73 m². However, several epidemiologic studies from unselected populations have shown that in patients with advanced CKD, the risk for death is higher than the future need for dialysis; this is the case for the elderly, in particular (2). Therefore, dialysis planning can be futile if it is to begin for every elderly patient with eGFR <30 mL/min/1.73 m².

Recent studies suggest that individuals with significant proteinuria, or an underlying primary renal disease, or with declining trajectory of renal function are more likely to need dialysis. If these issues, along with the patient’s functional status, are factored in when deciding which elderly patients with low eGFR should begin preparing for dialysis, the potential futility of the process could be reduced.

A role for maximum conservative management?

The life expectancy of patients starting dialysis therapy in the United States is about one-quarter of age- and sex-matched individuals without kidney disease, and elderly patients starting dialysis are no exception (1). The median life expectancy of dialysis patients between the ages of 75 and 79 is 2.9 years, compared with 10.8 years for individuals in the general population (3).

A recent study has focused on the dismal outcomes of frail elderly nursing home residents. An overwhelming majority of such patients experienced continued functional decline and/or death within 12 months of starting dialysis (4). Studies such as this suggest that in frail individuals with advanced CKD, starting dialysis may not necessarily improve their functional status and/or increase their life expectancy. These observations have also spurred interest in considering maximum conservative care as one of the therapeutic options for frail elderly patients with advanced CKD in lieu of preparation for dialysis, including anemia correction with erythropoietin, loop diuretics to prevent volume overload, phosphate-binders to manage itching, and potassium restriction as the only dietary intervention (5).

Choosing between maximum conservative management and renal replacement therapy requires shared decision-making that should involve the nephrologist, the patient, and the patient’s family. A time-limited trial of dialysis may facilitate decision-making for some patients. Patients who choose maximum conservative management or withdraw from dialysis after a time-limited trial may also be appropriate candidates for hospice care at some stage of their disease.

What is the optimal time to begin dialysis therapy?

In the United States, patients are starting dialysis therapy at progressively higher levels of eGFR; the higher the age, the greater the proportion of individuals who begin dialysis at an eGFR >10 mL/min/1.73 m² (1, 6). Several observational studies have shown an inverse relationship between eGFR at the start of renal replacement therapy and the subsequent risk for death, leading some to argue that it is the dialysis treatment itself that is at least partly responsible for the higher mortality in patients who start dialysis early (7). However, the same studies indicate that patients who begin dialysis at higher levels of eGFR are much more likely to be men, elderly, diabetic, and with greater cardiovascular comorbidity (7).

Given the lack of detail about the clinical status of individual patients in national registries such as the U.S. Renal Data System, it is unlikely that statistical adjustments will account for the greater disease burden of patients who begin dialysis at higher levels of renal function. Furthermore, the results of the recently published IDEAL study indicate that starting dialysis at higher levels of eGFR does not itself increase the risk for death (8). These considerations suggest that in symptomatic individuals, it is safe to start dialysis even if the eGFR is >10 mL/min/1.73 m². Conversely, dialysis may be safely withheld in otherwise asymptomatic individuals with lower eGFR. However, the results of the IDEAL study suggest that many elderly CKD patients with declining renal function are likely to require dialysis at higher levels of renal function (8).

Is one dialysis modality better than the other for elderly patients with ESRD?

The overwhelming majority of ESRD patients in the United States are treated with in-center hemodialysis; peritoneal dialysis remains the dominant home dialysis modality (1). Numerous observational studies have compared the outcomes of patients treated with in-center hemodialysis and peritoneal dialysis. These studies suggest that elderly patients treated with peritoneal dialysis, particularly those with diabetes mellitus and/or coexisting illnesses, have a somewhat shorter survival than those treated with in-center hemodialysis (9). However, over the past decade in the United States, improvements in the outcomes of peritoneal dialysis patients have outpaced those seen with in-center hemodialysis patients (10). Thus, in the most recent cohorts, the differences in survival seen in patients treated with either dialysis modality have substantially narrowed and are probably not clinical meaningful (11).

These findings suggest that the survival studies should have little if any bearing when assisting elderly patients and/or their families in selecting an appropriate dialysis modality. On one hand, the burden of coexisting diseases, frailty, and social isolation may make in-center hemodialysis a particularly attractive therapeutic option for many elderly ESRD patients. On the other hand, the ability to undergo dialysis at home may be perceived by some elderly patients as the best method for them to maintain their independence and dignity. Peritoneal dialysis has been successfully performed by octogenarians and nonagenarians, and this may be further facilitated by identifying family members or other support services that may provide assistance to patients to undergo home dialysis (12). Success of this concept of assisted home peritoneal dialysis has been reported from Canada, Denmark, and France, and should be considered for appropriate individuals. It follows, then, that the best dialysis modality for a patient is the one that best fits into their lifestyle and their expectations and goals for their care. Hence, all patients and/or their families should be offered the choice of all dialysis modalities whenever feasible under the oversight and encouragement offered by the health care team.

In conclusion, there are many unique challenges in the care of elderly ESRD patients. These challenges begin from the time of preparation for dialysis therapy to initiation and subsequently the maintenance of dialysis therapy. It is important to focus not only on longevity but also on quality of life and quality of death.