Kidney disease is a growing health concern, with millions of people worldwide requiring dialysis to replace the kidney function they have lost. For many on dialysis, a major question is whether their kidneys can heal and regain function while on dialysis or if the dialysis is only temporarily replacing lost function. In this article, we will examine what exactly kidney dialysis does, whether healing and improvement is possible during dialysis, factors that impact potential healing, and overall prognosis for those with chronic kidney disease on long-term dialysis.
What does dialysis do?
Dialysis is a treatment that filters waste products, extra salt and fluids from the blood when the kidneys are no longer able to do this adequately. This helps control blood pressure and maintain a healthy balance of electrolytes. There are two main types of dialysis:
Hemodialysis
Hemodialysis uses a special filter called a dialyzer to clean the blood. It is usually done 3 times per week at a dialysis center or hospital. Each session lasts 3-5 hours. The dialyzer, or artificial kidney, contains a membrane that allows waste products and extra fluid to cross over from the blood into a dialysate solution. The clean blood then flows back into the body.
Peritoneal dialysis
Peritoneal dialysis uses the lining of the abdomen and a dialysate solution to filter the blood inside the body. There are two main types:
– Continuous ambulatory peritoneal dialysis (CAPD) – the dialysate is exchanged 4-6 times per day. Each exchange takes about 30-40 minutes.
– Automated peritoneal dialysis (APD) – a machine called a cycler performs exchanges during the night while you sleep.
In both peritoneal dialysis and hemodialysis, the dialysis treatment filters out wastes, removes extra fluids and maintains electrolyte balance. This helps relieve symptoms and prevents complications of kidney failure. However, it does not cure or reverse kidney damage.
Can kidneys heal while on dialysis?
The short answer is yes, it is possible for kidneys to heal to some degree in patients on dialysis. However, the chances of full recovery are very low. Several factors impact whether the kidneys can improve during dialysis:
Cause of kidney disease
Some kidney diseases that cause chronic kidney failure, such as glomerulonephritis or kidney infection, can potentially improve over time. Dialysis supports the body while the kidneys have a chance to heal. However, kidney function may not return to normal.
Kidney diseases that progressively destroy the kidneys, like diabetic nephropathy or polycystic kidney disease, are less likely to heal, even on dialysis. However, progression may slow with good blood glucose or blood pressure control.
Duration of kidney disease
The longer someone has lived with severely reduced kidney function before starting dialysis, the lower their chances of recovery. Early intervention with dialysis gives the kidneys the best chance of healing.
Coexisting conditions
Factors like high blood pressure, diabetes, and autoimmune disorders can reduce the ability of the kidneys to heal while on dialysis. Controlling these coexisting conditions is key.
Age and overall health
Younger people and those in good overall health, without a lot of additional chronic illnesses, have better outcomes in terms of kidney recovery while on dialysis. Older age and many health problems decrease healing potential.
Adherence to treatments
Carefully following the dialysis schedule, medication regimen, fluid restrictions, and dietary guidelines recommended provides the best environment for kidney recovery. Non-adherence reduces chances the kidneys will improve.
How much improvement is possible?
Many patients on dialysis do see some degree of improvement in their kidney function. However, returning to normal kidney function or completely coming off dialysis is uncommon. Some examples of improvement include:
– Reduced uremia symptoms as the kidneys clear more waste products
– Improved urine output
– Decreased fluid retention
– Lower potassium and phosphorus blood levels
– Improved anemia due to increased natural erythropoietin production
– Increased estimated glomerular filtration rate (eGFR) from lab testing
However, for most the improvement is modest. The majority do not regain enough function to stop dialysis treatments altogether.
One study found 16% of patients on hemodialysis for greater than 1 year recovered partial kidney function. They were able to reduce their dialysis frequency and intensity. However, complete cessation of dialysis was rare. (Wang et al. 2012).
Monitoring for signs of kidney recovery
Doctors closely monitor dialysis patients for any signs of improvement in residual kidney function. Assessments include:
– Checking for increased urine output
– Monitoring electrolytes, waste products, and eGFR trends
– Evaluating blood pressure control
– Looking for reduced dialysis requirements
– Evaluating any changes in symptoms
This helps determine if dialysis prescriptions need to be adjusted and guides prognosis.
Prognosis for kidney disease patients on long-term dialysis
Patients who require lifelong dialysis due to end stage renal disease have shortened life expectancies. However, with excellent medical care, some live decades on dialysis.
According to the United States Renal Data System 2020 Annual Report, the 5-year survival rate is:
– Hemodialysis patients age 20-44: 58.6%
– Hemodialysis patients age 45-64: 36.5%
– Peritoneal dialysis patients age 20-44: 64.6%
– Peritoneal dialysis patients age 45-64: 45.5%
This compares to 95% 5-year survival in the general population. Younger individuals on dialysis tend to live longer than older patients.
Survival is improving but still severely impacted by kidney disease. Supporting kidney function as much as possible while on dialysis is key to prolonging life.
Conclusion
Some degree of kidney recovery and improvement is possible while on dialysis, especially with early intervention, proper treatment, and a disease that causes reversible damage. However, returning to fully normal kidney function is uncommon. If it occurs, it tends to be in younger patients.
While dialysis can buy the kidneys some time to heal, the majority of patients require lifelong dialysis without ever regaining full function. Staying on dialysis as prescribed, following all treatment guidelines, and maintaining overall health provides the only chance for the damaged kidneys to potentially improve.