Not all people with diabetes need dialysis, but diabetes is the single leading cause of kidney failure requiring it. About 38% of all end-stage kidney disease cases in the United States are caused by diabetes. The good news: most people with diabetes will never reach that point, and the risk has dropped significantly over the past few decades thanks to better treatments and earlier intervention.
Why Diabetes Damages the Kidneys
Your kidneys contain roughly one million tiny filtering units that clean your blood. When blood sugar stays elevated over months and years, excess glucose gets absorbed into the cells of these filters. That triggers a chain reaction: the extra glucose generates harmful byproducts that cause oxidative stress, which in turn stimulates your body to produce scar tissue inside the filters. Over time, this scarring thickens and stiffens the delicate filtering membranes, making them less and less effective at cleaning your blood.
This process, called diabetic kidney disease (or diabetic nephropathy), is gradual. It typically takes 10 to 20 years of poorly controlled blood sugar to cause serious damage. The kidneys have enormous reserve capacity, so you can lose a significant portion of your filtering ability before you notice anything wrong.
How Many People With Diabetes Actually Need Dialysis
The numbers are more reassuring than many people expect, and they’ve improved dramatically over time. For people with type 1 diabetes diagnosed after 1985, population studies from Sweden, Japan, and Finland found that only 3% to 10% developed kidney failure after 30 years of living with the disease. In the landmark DCCT/EDIC trial, which studied people with type 1 diabetes who managed their blood sugar carefully, just 1% to 2% reached kidney failure after 30 years.
That’s a sharp contrast to earlier decades. Among people diagnosed with type 1 diabetes between 1950 and 1964, nearly half needed dialysis or a transplant within 40 years. The difference reflects how much better blood sugar management and kidney-protective medications have become. For type 2 diabetes, the overall risk is harder to pin down because the population is so much larger, but the same trend holds: better management means fewer people progressing to dialysis. Still, because type 2 diabetes is far more common, it accounts for the majority of diabetes-related dialysis cases.
Warning Signs of Kidney Decline
Early diabetic kidney disease has no symptoms at all. That’s what makes it dangerous. The first detectable sign is usually protein leaking into your urine, something you won’t notice but that shows up on a simple urine test. This is why routine screening matters so much if you have diabetes.
By the time symptoms appear, significant damage has already occurred. Later-stage signs include:
- Foamy urine from excess protein
- Swelling in your feet, ankles, hands, or around your eyes
- Blood pressure that becomes harder to control
- Fatigue and weakness that doesn’t improve with rest
- Shortness of breath from fluid buildup
- Nausea, vomiting, or loss of appetite
- Confusion or difficulty thinking clearly
- Persistent itching
If you have diabetes, a yearly urine test for protein and a blood test measuring your kidney filtration rate (called eGFR) can catch problems years before symptoms develop. Kidney disease found early is much easier to slow down or stabilize.
How Kidney Disease Is Staged
Kidney function is measured on a five-stage scale based on your eGFR, which estimates how well your kidneys are filtering. A normal eGFR is above 90. Stage 3 (eGFR between 30 and 59) is where most people first get a diagnosis, because earlier stages rarely cause noticeable problems. Stage 4 (eGFR 15 to 29) means severe reduction. Stage 5 (eGFR below 15) is kidney failure, where dialysis or a transplant becomes necessary to survive.
Not everyone who reaches stage 3 progresses further. Many people stabilize at moderate kidney disease for years or even decades with proper treatment. The rate of progression depends heavily on blood sugar control, blood pressure management, and whether kidney-protective medications are started early.
Medications That Reduce the Risk
A class of medications originally developed for blood sugar control has turned out to be remarkably effective at protecting the kidneys. In a meta-analysis of nearly 39,000 people with type 2 diabetes, these drugs (called SGLT2 inhibitors) reduced the risk of dialysis, kidney transplant, or death from kidney disease by 33%. They also cut the risk of kidney failure by 35% and reduced acute kidney injury by 25%. These benefits held true even for people whose kidneys were already moderately damaged, with an eGFR as low as 30 to 45.
Blood pressure medications that block the renin-angiotensin system (commonly prescribed as ACE inhibitors or ARBs) have been a cornerstone of kidney protection for decades. Combined with tight blood sugar control and the newer kidney-protective drugs, the toolkit for preventing dialysis is stronger than it has ever been.
What Dialysis Actually Looks Like
If kidney disease does progress to the point where dialysis is needed, there are two main options. Hemodialysis is the more common form: a machine filters your blood through an external circuit. Most people do this at a dialysis center three times a week, with each session lasting 3 to 5 hours. A home option exists that involves shorter daily sessions of about two hours, six or seven days a week.
Peritoneal dialysis uses the lining of your abdomen as a natural filter. You fill your abdominal cavity with a special fluid, let it absorb waste products, then drain it. This can be done at home and offers more flexibility in your schedule. It also costs about 30% to 40% less than hemodialysis. However, for people with diabetes specifically, peritoneal dialysis carries some additional risks, including higher rates of infection, difficulty controlling blood sugar (the dialysis fluid contains glucose), and problems with fluid balance. A large meta-analysis of 17 studies found that diabetic patients on hemodialysis had about a 20% lower risk of death compared to those on peritoneal dialysis.
The choice between the two depends on your overall health, lifestyle preferences, and what your kidney specialist recommends. Neither option is painless or easy, which is why prevention and early treatment matter so much.
Survival on Dialysis
Dialysis is life-sustaining, but it does carry real health risks. Among people with type 1 diabetes who started dialysis between 2000 and 2005, about 67% survived at least five years, and median survival exceeded eight years. That’s a significant improvement from the 1980s, when only about half survived five years after starting dialysis. Outcomes for type 2 diabetes vary more because of the wider age range and the burden of other conditions like heart disease.
A kidney transplant, when available, generally offers better long-term outcomes than staying on dialysis. Many people with diabetes are evaluated for transplant eligibility once their kidney function drops to stage 4 or early stage 5.
When Dialysis Starts
Dialysis doesn’t begin at a fixed eGFR number. A large clinical trial compared starting dialysis at an eGFR of around 10 versus waiting until eGFR dropped to 5 to 7, and found no survival difference between the two approaches. The current consensus is that dialysis should start based on symptoms, not a lab value alone. When waste products build up enough to cause nausea, severe fatigue, fluid overload, or confusion, that’s typically when dialysis begins, usually somewhere in the eGFR range of 5 to 10. The same criteria apply whether you have diabetes or not.