Diabetic Nephropathy Treatment

Diabetic nephropathy is a severe complication of type 1 diabetes and type 2 diabetes. It is also called diabetic kidney disease. 

Diabetic nephropathy interferes with the kidneys' ability to remove waste products and extra fluid from the body. The ideal way to prevent or delay the onset of diabetic nephropathy is to maintain a healthy lifestyle, work out regularly, and manage blood sugar levels and high blood pressure efficiently.

Kidney disease may progress to kidney failure, which is also called end-stage renal disease. Kidney failure is a life-threatening condition. At this stage, treatment options are dialysis or a kidney transplant.

Symptoms of Diabetic Nephropathy

No signs and symptoms of diabetes are evident during the early stages of diabetic nephropathy. In later stages, the signs and symptoms may include:

• Worsening blood pressure control
• Protein in the urine
• Drowsiness
• Muscle twitching
• Increased need to urinate
• Swelling of feet, ankles, hands, or eyes
• Loss of appetite
• Shortness of breath
• Reduced need for insulin or diabetes medicine
• Confusion or difficulty concentrating
• Nausea and vomiting
• Persistent itching
• Fatigue

As the renal damage progresses, kidneys cannot function properly, thereby building up waste in the body that may reach toxic levels, a condition known as uremia. People with uremia are often confused and occasionally become comatose.

Stages of Diabetic Nephropathy

The stages of kidney disease depend on the GFR, representing the percentage of effective kidney function.

• Stage 1: Kidney damage but normal kidney function and a GFR of 90% or more.
• Stage 2: Kidney damage with loss of function and a GFR of 60–89%.
• Stage 3: Mild to serious loss of function along with GFR of 30–59%.
• Stage 4: Loss of function and GFR of 15–29%.
• Stage 5: Renal failure and a GFR of less than 15%.

Causes of Diabetic Nephropathy

Kidney damage can put pressure on other healthy organs and prevent them from functioning well. When this happens:

• the body loses protein through the urine
• the kidneys fail to remove waste products from the blood
• the kidneys fail to balance healthy fluid levels in the body

Diabetic nephropathy is the result of uncontrolled diabetes. It develops slowly over the years. Kidney disease is also common in people with diabetes for less than ten years. Also, if there are no clinical signs of nephropathy 20–25 years after diabetes is diagnosed, there are fewer chances of developing it.

Diabetic nephropathy is less likely to develop if a person with diabetes manages their glucose levels effectively.

Increased blood glucose levels increase the risk of high blood pressure. This happens because of the damage done to blood vessels. Hypertension may also contribute to kidney disease.

Diabetic Nephropathy Diagnosis

Diabetic nephropathy is diagnosed during routine examination as a part of diabetes management. Screening for diabetic nephropathy is recommended at least five years after diagnosis of type 1 diabetes. With type 2 diabetes, the screening begins at its diagnosis.

Routine screening tests include:

• Urinary albumin test: This test detects the blood protein albumin in the urine. Under normal circumstances, the kidneys don't filter albumin out of the blood. Excessive protein in the urine may indicate poor kidney function.
• Albumin/creatinine ratio: Creatinine is a waste product filtrated from the blood by healthy kidneys. The albumin/creatinine ratio helps assess kidney function.
• Glomerular filtration rate (GFR): It is the measure of creatinine in a blood sample that helps estimate how quickly the kidneys filter blood (glomerular filtration rate). The glomerular filtration rate is low for a kidney that is not functioning.

Other diagnostic tests include:

• Imaging tests: X-rays and ultrasound tests help assess the kidneys' structure and size. CT scans and magnetic resonance imaging (MRI) may also be advised to determine blood circulation within the kidneys.
• Kidney biopsy: A kidney biopsy is recommended to study the anatomy of kidney tissue. 

Diabetic Nephropathy Treatment

The first line of treatment for diabetic nephropathy is treating and controlling diabetes and hypertension. This includes changes in diet and lifestyle, adding exercise to the routine, and prescription medications. Good blood sugar and hypertension management can prevent or delay the onset of kidney dysfunction and other such complications.

Medications

The early stages of diabetic nephropathy can be managed with medications that include:

• Blood pressure control: Medicines such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin-2 receptor blockers (ARBs) are prescribed to manage high blood pressure.
• Blood sugar control: Medicines that help control high blood sugar in people with diabetic nephropathies, such as metformin, improve insulin sensitivity and lower glucose production in the liver. Glucagon-like peptide 1 (GLP-1) receptor agonists reduce blood sugar levels by slowing digestion and stimulating insulin secretion in response to rising glucose levels. SGLT2 inhibitors limit glucose to return to the bloodstream, leading to increased glucose excretion in the urine.
• High cholesterol: Cholesterol-lowering drugs called statins are prescribed to lower high cholesterol levels and reduce protein in the urine.
• Kidney scarring: Finerenone disrupts molecular activity that causes inflammation and tissue scarring in diabetic nephropathy. Research suggests that the drug may lower the risk of kidney function decline, kidney failure, nonfatal heart attacks, cardiovascular death, and hospitalisation for heart failure in patients with chronic kidney disease associated with type 2 diabetes.

Kidney transplant

If kidney disease progresses to kidney failure (end-stage kidney disease), care is focused on either replacing the kidneys' function or making the patient more comfortable. In some situations, the best option is a kidney transplant or a kidney-pancreas transplant. If a kidney transplant is chosen, the patient's eligibility as a recipient is tested.

Complications Of Diabetic Nephropathy

The complications of diabetic nephropathy develop gradually over months or years. These include:

• Fluid retention causes swelling in the arms and legs, high blood pressure, or fluid in the lungs (pulmonary oedema)
• Increase in potassium levels in the blood (hyperkalemia)
• Heart and blood vessel disease (cardiovascular disease) can lead to stroke
• Prolonged high sugar levels can damage the blood vessels of the light-sensitive tissue at the back of the eye, called diabetic retinopathy
• Pregnancy complications that carry risks for the mother and the developing fetus
• Anaemia: Reduced number of red blood cells to transport oxygen 
• Foot sores, erectile dysfunction, diarrhoea, and other disorders related to damaged blood vessels and nerves
• Particular bone and mineral disorders due to the inability of kidneys to balance calcium and phosphorus levels in the blood
• Irreversible damage to the kidneys is called end-stage kidney disease, which eventually needs either dialysis or a kidney transplant for survival

Risk Factors

Factors that contribute to an increased risk of diabetic nephropathy include:

• Uncontrolled high blood sugar (hyperglycemia)
• Uncontrolled high blood pressure (hypertension)
• Being a smoker
• Age: above 60 years
• High blood cholesterol
• Obesity
• It is more common in men than in women
• A family history of diabetes and kidney disease
• Chronic inflammation
• Insulin resistance 
• Elevated levels of blood lipids (fats)

Prognosis

The progression of kidney disease depends upon many factors. Following the treatment plan and making recommended lifestyle changes can slow the disease’s progression and keep the kidneys healthy for a longer duration.

Review 

Reviewed by Dr. Manoj Arora, Director - Nephrology, on 7 Dec 2024.