Home Hemodialysis: Clinical Benefits, Risks, Target Populations

Abstract

Home hemodialysis, and in particular intensive home hemodialysis, has seen renewed development since the early 2010s, linked to low-flow dialysate techniques and the use of more manageable monitors. A number of studies have demonstrated a clinical benefit in terms of survival and cardiovascular risk reduction, pointing in particular to this technique in patients at high cardiovascular risk and with difficult access to renal transplantation. However, these benefits must be balanced against potential risks linked essentially to the increased frequency of sessions rather than being at home: increased complications of vascular approaches, loss of residual renal function, and burnout. Optimal patient selection, appropriate training, and regular follow-up will optimize the benefits relative to the potential risks.

Introduction

Conventional in-center hemodialysis is associated over the long term with a high rate of cardiovascular complications and poor quality of life. Renal transplantation remains the treatment guaranteeing the best survival but has an average waiting time of over 2 years and restricted access for certain populations, notably elderly patients, those at high immunological risk, those with severe cardiovascular comorbidities, and obese patients. These difficulties of access to transplantation underline the importance of developing alternatives to conventional hemodialysis in order to optimize chronic dialysis patients’ quantity and quality of life.

Home hemodialysis (HHD) was first introduced in the 1960s, with rapid expansion due to dialysis units’ inability to meet patient demand. A marked decline was then observed with the development of self-dialysis units and changes in reimbursement policies. Since the 2010s, there has been a resurgence in HHD linked to the demonstrated clinical benefits of intensive hemodialysis and technical innovations including the use of low-flow dialysate[1]. However, HHD remains largely underutilized, accounting for just 1% of hemodialysis patients in France. This underutilization is mainly due to a lack of training for caregivers and information for patients, as well as a lack of incentive policies.

This review aims to reiterate the proven clinical benefits of HHD versus the potential risks and to reiterate patient eligibility criteria and contraindications.

Clinical Benefits

The clinical benefits of HHD are essentially related to the intensity of dialysis, which for logistical reasons is more easily achieved at home. Intensive home hemodialysis (IHHD) is defined as either an increase in the frequency of sessions (minimum of 5 sessions per week) with a reduction in their duration (2-3 h, short daily hemodialysis (SDHD)) or an increase in the duration of sessions to more than 5,5 h, 3-4 times per week, generally performed at night (long nocturnal hemodialysis, LNHD), or an increase in both the duration and frequency of sessions (Table I). The technique most widely used in the United States and France is SDHD.

Table I.Home hemodialysis procedures, adapted from[16]

Terms and conditions	Sessions /week	Session duration (h)	Qs (ml/min)	Qd (ml/min)	Base (mmol/l)	K+ (mmol/l)	Ca2+ (mmol/l)	Add P04
CHD	3-3,5	3-5	300-400	500-800	HC03-, 32-36	2	1,25	No
Alternating LNHD	3,5	6-8	250-350	300-500	HC03-, 28-35	2	1,25	Rarely
Traditional SDHD	5-6	2,5-3,5	350-400	350-600	HC03-, 32-36	2	1,25	No
Traditional LNHD	4-6	6-8	250-300	300	HC03-, 28-35	3	1,5-1,75	20-30% sessions
LFD SDHD	5-6	2,5-4	300-400	90-300	lactate, 40-45	1-2	1,5	No
LFD LNHD	4-6	6-8	300-350	83-166	lactate, 40-45	2	1,75	No

Survival

To date, no randomized controlled trial has demonstrated a significant survival advantage for IHHD over conventional hemodialysis (CHD). Survival data from randomized trials on this subject come from the Frequent Hemodialysis Network (FHN) studies. The FHN daily study[2]found a significant difference in the primary composite endpoint of fewer deaths and less left ventricular hypertrophy (LVH) in the frequent hemodialysis group (center-based) compared with the conventional hemodialysis group. This study was then extended over a median period of 3,6 years (range 1,5 to 5,3 years) after randomization, with the observation of lower mortality and a relative risk (RR) of mortality for frequent hemodialysis versus conventional hemodialysis of 0,54[3]. With regard to LNHD, the FHN nocturnal study[4]found no difference in terms of survival or reduction in LVH. These negative results were possibly linked to the high proportion of residual renal function (RRF) loss in the LNHD group (compared with an unusually high RRF in the CHD group) and, above all, to underpowering of the mortality study (low mortality in the CHD group, small number of patients, insufficient compliance with nocturnal treatment). The study was then extended to 5 years[5], with an increase in mortality observed in the LNHD group, but with an increase in the dialysis dose for a large number of patients in the CHD group, with more than 3 sessions per week and more than 27 hours of dialysis per week after the first 12 months, making any final interpretation difficult.

Other survival data on IHHD are derived from observational studies, with all the limitations inherent to these studies’ characteristics, but partly offset by the large number of studies showing a survival benefit of IHHD over CHD. In particular, LNHD was found to be beneficial in several studies, with a reduction in the RR of mortality[6][7][8]. In the case of SDHD, Blagg et al. found a reduction in mortality with an RR reduction of 0,39 in comparison with incident patients from the United States Renal Data System (USRDS) registry[9][10]Kjellstrand et al. observed a 2- to 3-fold increase in survival compared with a group of CHD patients[9]. Marshall et al. reviewed the Australian and New Zealand registries comparing CHD with different HHD modalities and found a nonsignificant survival advantage for IHHD (RR 0,56) versus CHD, while home CHD had the same mortality rate[11][12]. Rydell et al. carried out a cohort study with 152 incident patients receiving home hemodialysis (15 hours per week) at high flow, performed diurnally and nocturnally, compared with 608 patients on CHD and 456 on peritoneal dialysis (PD) over a mean duration of 10,4 years, and observed an increase in survival in the HHD group compared with the CHD and PD groups[13].

With regard to SDHD at low dialysate flow,

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