Diabetes and kidney disease: understand the link

Diabetes is a leading cause of kidney disease, but understanding the connection between these conditions can help you manage and prevent complications, explains Dr Elmo Pretorius, an endocrinologist at Mediclinic Vergelegen.

How does diabetes lead to kidney disease?

The relationship between diabetes and kidney disease is complex, says Dr Pretorius. “The kidney is an organ made up of specialised blood vessels, called the glomeruli, which form filters that get rid of blood waste products through the urine. The high blood glucose in diabetes causes damage to blood vessels, including these specialised blood vessels, and affects them through inflammation.”

This damage leads to the glomeruli leaking proteins into the urine that were supposed to be retained in the blood. Over time, the filters become so damaged and scarred that they’re unable to function. As a result, the kidneys can no longer perform their crucial task of cleaning the blood of waste products. Dr Pretorius says almost a third of all people with diabetes will develop kidney damage, and in half of people with end-stage kidney disease – which requires dialysis – the cause is diabetes.

One of the significant challenges is that the early signs of kidney disease are often silent. “Patients with diabetes should have their kidney function checked at least once a year through a blood test. They should also have their urine checked for protein," says Dr Pretorius. "Once a patient starts showing symptoms of kidney disease, it’s usually too late to prevent any further progression."

What are the treatment options for diabetes-related kidney disease?

Prevention is always better than cure, and this is especially true for diabetes-related kidney disease. "Good glucose control is imperative to prevent kidney damage," says Dr Pretorius. Various treatment options exist to manage diabetes and its complications effectively. Diet and lifestyle play a big role in improving diabetes control.

Another critical factor in preventing kidney disease is managing high blood pressure (hypertension). Dr Pretorius recommends antihypertensive drugs called renin-angiotensin system (RAS) blockers. Among them are ACE inhibitors and angiotensin receptor blockers, which are particularly effective in preventing kidney damage in patients with diabetes. Cholesterol control with statins (a group of cholesterol-lowering drugs) is also crucial, given the high cardiovascular risk in patients with diabetes and kidney disease.

For those living with diabetes, recent advancements in diabetes medications have also shown promise in protecting kidney health. “Exciting diabetes drugs have been shown to protect the kidney against damage. These include SGLT-2 inhibitors and GLP-1 agonists,” Dr Pretorius explains. They’re effective in preventing the progression of kidney disease and have even shown benefits in people without diabetes.

A new drug called Finerenone has also been introduced to the market, offering protection against kidney damage in diabetes patients. Although not yet available in South Africa, Dr Pretorius is hopeful that it will soon be part of a comprehensive strategy to protect the kidneys of patients with diabetes. Always consult your doctor before taking new drugs or changing medications.

Can you reverse kidney damage from diabetes?

It’s possible to reverse kidney damage from diabetes, particularly in the early stages, says Dr Pretorius, which is why early screening is important. "In the early stage, the leaky glomeruli can repair and recover if blood pressure and diabetes are controlled with the right combination of drugs and healthy lifestyle changes," he explains

Making changes to your lifestyle is important for preventing and possibly reversing kidney damage. This includes keeping your glucose (sugar), blood pressure, and cholesterol levels under control. A healthy diet, rich in plant-based proteins, low in saturated and trans fats, and high in fibre, is essential. Limiting alcohol intake, ensuring adequate hydration, and avoiding smoking are also crucial steps.

Exercise is another key component for anyone living with diabetes. “Patients should aim for at least 30 minutes of moderate intensity exercise a day," advises Dr Pretorius. Avoiding medicines that may damage the kidneys, such as anti-inflammatory drugs, is also important for protecting kidney health.

It’s important to know how diabetes and kidney disease are linked so you can prevent and manage complications. Regular check-ups, detecting any issues early, and controlling diabetes effectively are crucial for keeping your kidneys healthy. With the right treatments and lifestyle adjustments, you can reverse early kidney damage and improve your quality of life. A supportive healthcare team can help people with diabetes handle these challenges and stay healthier overall.

To find an endocrinologist near you, click here.