What is dialysis and when is it needed?

Dialysis takes over the filtering work of failed kidneys — removing waste products, excess fluid, potassium and acid from the blood. It is needed when kidney function falls to the point where symptoms and biochemical disturbance can no longer be managed medically: typically an eGFR below about 10, or earlier if there is fluid overload unresponsive to diuretics, resistant hyperkalaemia, acidosis, uraemic symptoms such as nausea, itching and confusion, or pericarditis. There are two main forms: haemodialysis, where blood is pumped through a filter outside the body, usually three times a week; and peritoneal dialysis, which uses the lining of the abdomen as the filter and is performed at home daily. Neither cures kidney failure — transplantation is the only treatment that restores kidney function.

Why does the type of dialysis access matter so much?

Because it is one of the strongest determinants of how well someone does on dialysis. An arteriovenous fistula — where a surgeon joins an artery to a vein, usually in the arm, so the vein enlarges and thickens enough to be needled — has far lower infection rates, lasts longer and is associated with better survival than the alternative. The catch is time: a fistula needs to be created months in advance so it can mature. If someone is referred late and needs dialysis urgently, the only option is a tunnelled catheter into a large central vein, which carries a high risk of bloodstream infection and can damage the central veins permanently. This is also why the veins of the non-dominant arm should be protected in anyone with advancing kidney disease — no routine cannulas, no drips, no PICC lines.

Is it acceptable to choose not to have dialysis?

Yes, and for some patients it is the better choice. In frail older people with several other serious conditions, dialysis may add relatively little time while consuming a great deal of it — three sessions a week plus travel and recovery, frequent hospital admissions, and in nursing home residents a documented decline in function after starting. Conservative kidney management is not withdrawal of care: it involves active treatment of anaemia, fluid overload, itching, nausea and other symptoms, dietary support, careful medication management, advance care planning and palliative care input. Studies comparing the two approaches in the very elderly with significant comorbidity show similar survival in many cases, with better quality of life and far fewer days spent in hospital. Presenting this honestly as a genuine option is part of good practice.

Why do so many people die of kidney failure worldwide?

Because dialysis and transplantation exist but are not accessible. Around four million people worldwide receive kidney replacement therapy, but modelling suggests that somewhere between five and eleven million people die each year from kidney failure they could have survived. Access maps almost exactly onto national income: essentially universal in wealthy countries, and reaching only a fraction of those who need it in many low-income settings, where patients often present already needing dialysis, receive a few sessions until money runs out, and are then discharged to die at home. The barriers are cost, absence of insurance coverage, geographical distance from the few available units, shortage of trained nephrologists and nurses, and unreliable water and electricity supply. This makes kidney failure one of the clearest examples of an outcome determined by geography rather than biology.

Is transplantation better than dialysis?

For suitable candidates, yes — substantially. Transplantation gives better survival, better quality of life, freedom from the treatment schedule, fewer dietary and fluid restrictions, and lower long-term costs to health systems. The best outcomes of all come from pre-emptive transplantation, performed before dialysis is ever started, and from living donors, whose kidneys function better and longer than those from deceased donors. Blood group and antibody incompatibility, once absolute barriers, can now often be overcome through paired exchange schemes, where incompatible donor-recipient pairs swap, or through desensitisation. Transplantation is not without cost: lifelong immunosuppression carries infection and cancer risks, and grafts eventually fail. But for most patients who are fit enough, it is clearly the superior option, and the main obstacles are late referral and inadequate donation systems rather than clinical suitability.

How does GMJ News cover dialysis and kidney replacement therapy?

GMJ News covers the global access gap and excess mortality from untreated kidney failure, vascular access planning and the fistula-first principle including vein preservation, home therapy under-use and its structural causes, conservative kidney management as an active option, transplantation including pre-emptive and living donation, paired exchange and the Declaration of Istanbul on organ trade, haemodiafiltration and the CONVINCE trial, peritoneal dialysis and peritonitis, dialysis adequacy and residual kidney function, mineral and bone disorder and vascular calcification, cardiovascular mortality and symptom burden, and dialysis in disasters and conflict. Directly relevant to PHIG's kidney health, health financing and emergency preparedness programmes.

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Dialysis and Kidney Replacement Therapy

GMJ News knowledge hub · last reviewed September 2026 · Georgian Medical Journal

Summary Statistics Glossary GMJ news FAQ Documents Organizations Research

Kidney replacement therapy sustains the lives of an estimated 4 million people worldwide, yet this figure represents a profound inequity rather than an achievement: modelling suggests that between 5 and 11 million people die each year from untreated kidney failure because dialysis and transplantation are simply unavailable or unaffordable to them, making kidney failure one of the starkest examples of a treatable condition whose outcome is determined almost entirely by geography and income (WHO). Within health systems that do provide therapy, the defining clinical priorities are: timely planning of vascular access, since an arteriovenous fistula created months in advance delivers substantially better survival and fewer infections than a tunnelled central venous catheter started urgently; the systematic under-use of home therapies — peritoneal dialysis and home haemodialysis — which offer comparable outcomes with greater autonomy at lower cost; and the recognition that in frail elderly patients with multiple comorbidities, conservative kidney management without dialysis may deliver similar survival with substantially better quality of life and fewer hospital days, making it a legitimate active treatment choice rather than a withdrawal of care.

Key messages

Millions die each year from untreated kidney failure — a problem of access, not knowledge

Around 4 million people worldwide receive kidney replacement therapy, but modelling suggests that between 5 and 11 million people die annually from untreated kidney failure because dialysis and transplantation are unavailable or unaffordable. Coverage tracks national income almost perfectly: essentially universal in high-income countries, and available to only a small minority in many low-income settings, where patients are commonly diagnosed at the point of needing dialysis and then sent home to die. Kidney failure is therefore among the starkest examples of a treatable condition whose outcome is determined by geography and income rather than biology.

Fistula first — vascular access planning determines survival

The arteriovenous fistula — a surgically created connection between an artery and vein, usually in the forearm or upper arm — has substantially better outcomes than any alternative: lower infection rates, longer patency, fewer interventions and better survival. It requires creation MONTHS in advance because it must mature before use. Tunnelled central venous catheters, by contrast, carry high rates of bacteraemia, central venous stenosis and thrombosis, and are associated with worse survival — yet remain the commonest starting access in many systems because referral was late. Protecting veins in patients with advancing CKD — avoiding cannulation and PICC lines in the non-dominant arm — is a simple, high-value intervention that is routinely neglected on general wards.

Home therapies are systematically under-used

Peritoneal dialysis and home haemodialysis deliver comparable clinical outcomes to in-centre haemodialysis, with substantially greater patient autonomy, better preservation of residual kidney function in the case of PD, no travel burden, and lower cost to the health system. Despite this, uptake varies enormously between countries for reasons that are structural rather than clinical: reimbursement models that favour in-centre treatment, workforce and training gaps, late referral leaving no time for modality education, and unit culture. Countries such as Hong Kong operate PD-first policies with excellent results, demonstrating that the variation reflects policy choices rather than patient suitability.

Conservative kidney management is an active treatment choice, not withdrawal of care

For frail elderly patients with multiple comorbidities — particularly those over 80 with significant functional impairment or ischaemic heart disease — dialysis may extend life only marginally while consuming a large proportion of remaining time in hospitals and dialysis units, with recognised functional decline after initiation in nursing home residents. Comprehensive conservative kidney management provides active symptom control, anaemia and fluid management, dietary support, advance care planning and palliative input without dialysis, and can deliver similar survival with better quality of life and far fewer hospital days. Presenting it honestly as a legitimate option, rather than as giving up, is a core competence in nephrology.

Transplantation is the best outcome — and living donation is under-developed

Kidney transplantation offers better survival, better quality of life and lower long-term cost than dialysis for suitable candidates, and pre-emptive transplantation before dialysis starts gives the best outcomes of all. Living donation gives superior graft survival to deceased donation and permits planning, and paired exchange (kidney swap) programmes and desensitisation now overcome most blood group and antibody incompatibility. The barriers are again largely systemic: late referral, incomplete work-up, inequitable listing practices, and in many countries the absence of a functioning deceased donor programme or legal framework. Living donor safety requires rigorous evaluation, long-term donor follow-up, and explicit protection against any form of organ trade.

Dialysis is a treatment, not a cure — cardiovascular disease dominates outcomes

Patients starting dialysis face annual mortality far higher than most cancers, with cardiovascular disease accounting for around half of deaths — driven by accelerated vascular calcification, left ventricular hypertrophy, uraemic cardiomyopathy, chronic inflammation and mineral bone disorder rather than conventional risk factors alone. Symptom burden is also underestimated and undertreated: fatigue, pruritus, restless legs, cramps, sleep disturbance, sexual dysfunction and depression are common and frequently unaddressed. Intradialytic hypotension, myocardial stunning from ultrafiltration, and the excess mortality following the long interdialytic interval in thrice-weekly schedules are all recognised, modifiable contributors.

Key statistics

~4 million

people worldwide receive kidney replacement therapy

ISN Global Kidney Health Atlas

5-11 million

estimated annual deaths from untreated kidney failure due to lack of access

Lancet/ISN

Fistula first

arteriovenous fistula gives lower infection, better patency and better survival than catheters

KDOQI/ERA

Home therapies

comparable outcomes with greater autonomy and lower cost — uptake varies by policy, not clinical need

ISN/KDIGO

~50%

of deaths on dialysis are cardiovascular

USRDS/ERA registry

Pre-emptive

transplantation before dialysis starts gives the best outcomes of all modalities

KDIGO/ERA

Kidney replacement therapy — relative outcomes and system considerations

Source: ISN/KDIGO/registry data. Transplantation is superior where feasible; home therapies are under-used relative to their outcomes.

Glossary of key terms

Haemodialysis and haemodiafiltration
Nephrology/TechnologyHaemodialysis removes solutes by diffusion across a semipermeable membrane down concentration gradients, and removes fluid by ultrafiltration under a pressure gradient. Conventional schedules are three sessions of 4 hours per week, though longer or more frequent regimens — nocturnal, short daily — give better phosphate and fluid control and blood pressure. Haemodiafiltration adds substantial convective clearance, improving removal of middle molecules such as beta-2 microglobulin; the CONVINCE trial demonstrated a survival advantage for high-dose haemodiafiltration over high-flux haemodialysis, strengthening the case for its wider adoption where water quality and infrastructure permit. Key prescription variables: dialysate composition, ultrafiltration rate (high rates cause myocardial stunning and intradialytic hypotension), anticoagulation, and dialyser membrane and surface area.

Peritoneal dialysis
NephrologyUses the patient's own peritoneal membrane as the dialysing surface: dialysate is instilled into the peritoneal cavity through a permanent catheter, solutes diffuse across the peritoneum, and fluid is removed osmotically using glucose, icodextrin or amino acid solutions. Modalities: continuous ambulatory PD with manual exchanges through the day, and automated PD using a cycler overnight. Advantages: home-based, gentler haemodynamically, better preservation of residual kidney function, no vascular access needed, greater dietary freedom. Complications: peritonitis, which is the dominant cause of technique failure and requires prompt intraperitoneal antibiotics; exit-site infection; catheter malfunction; hernia and leaks from raised intra-abdominal pressure; and encapsulating peritoneal sclerosis, a rare but serious late complication.

Dialysis adequacy and residual kidney function
NephrologyAdequacy has traditionally been assessed by urea clearance (Kt/V) and urea reduction ratio, but these capture only small-solute clearance and correlate poorly with how patients actually feel. Increasing dialysis dose beyond adequacy targets did not improve survival in the HEMO and ADEMEX trials, which reoriented the field towards other determinants: fluid management and avoiding excessive ultrafiltration rates; blood pressure control; phosphate and mineral bone disorder; anaemia; nutrition; and symptom burden. Residual kidney function deserves particular emphasis — even small amounts of native urine output substantially improve fluid and middle-molecule clearance and are independently associated with survival, so it should be actively protected by avoiding nephrotoxins, avoiding aggressive ultrafiltration and hypotension, and preferring incremental dialysis where feasible.

Mineral and bone disorder in kidney failure
Nephrology/EndocrinologyCKD-mineral and bone disorder links biochemical abnormalities, bone disease and vascular calcification, and is a major driver of the cardiovascular mortality that dominates dialysis outcomes. Mechanism: declining GFR causes phosphate retention and reduced calcitriol production, raising FGF23 and parathyroid hormone; sustained secondary hyperparathyroidism produces high-turnover bone disease, while over-suppression produces adynamic bone, and both increase fracture risk. Calcium-phosphate product deposition drives medial arterial calcification, arterial stiffness and left ventricular hypertrophy. Management: dietary phosphate restriction focused particularly on inorganic phosphate additives in processed foods, which are far more bioavailable than organic phosphate; phosphate binders; active vitamin D analogues; calcimimetics; and parathyroidectomy in refractory disease.

Deceased and living donor transplantation
TransplantationDeceased donation includes donation after brain death and donation after circulatory death, with allocation governed by national systems balancing utility, equity and waiting time. Living donation offers better graft survival, shorter cold ischaemia and the possibility of pre-emptive transplantation. Immunological barriers that once precluded transplantation are increasingly surmountable: paired kidney exchange programmes allow incompatible pairs to swap donors, and desensitisation protocols permit ABO-incompatible and some HLA-incompatible transplants. Long-term graft loss is driven by chronic antibody-mediated rejection, recurrent disease, calcineurin inhibitor toxicity and non-adherence. Ethical governance is essential: transplant tourism and organ trafficking exploit the poorest, and the Declaration of Istanbul provides the international framework prohibiting organ trade and promoting national self-sufficiency.

Dialysis in disasters and conflict
Emergency preparednessDialysis-dependent patients are uniquely vulnerable in emergencies, because missing sessions causes hyperkalaemia, pulmonary oedema and death within days. Earthquakes additionally generate crush syndrome with rhabdomyolysis-induced acute kidney injury, creating a surge in demand exactly when infrastructure is destroyed — the experience that led to the establishment of renal disaster relief task forces. Conflict destroys dialysis capacity through damage to facilities, interruption of water and electricity, supply chain failure for consumables, and displacement of both patients and staff, with documented consequences in several recent conflicts. Preparedness measures: patient education on emergency diets and missed-session protocols, portable medical records, mutual aid agreements between units, mobile and peritoneal dialysis capability, and inclusion of kidney failure patients in humanitarian planning, where they are frequently overlooked.