Health Tips

Diabetes and kidney disease have a tight-knit relationship, to the point that a term is coined for kidney disease attributed to diabetes: diabetic kidney disease. Between 1990 and 2012, the number of deaths attributed to DKD rose by 94% – yet it is still heavily under-recognized by many people, especially diabetic patients. 

In the United States, diabetic kidney disease is the leading cause of end-stage renal failure (ESRD, also known as the dialysis stage). Things are not looking good at our home country either. It is reported that the number of Malaysians with long-term kidney disease is projected to significantly increase in the future due to increasing cases of diabetes and high blood pressure. The number of Malaysians who are required to undergo dialysis is also expected to rise over the years.

So why is this worrying? 

When your kidney goes out of business

Our kidneys remove wastes and extra fluids from our blood, and things can get really bad if they start to go out of business. Chronic kidney disease (CKD) is a condition in which the kidneys lose some of their ability to remove waste products and excess fluid from the bloodstream. As waste products and fluids build up in the body, other body systems are affected, which can be harmful to your health. Diabetic kidney disease is a form of CKD that is attributed to diabetes. Other causes of CKD include high blood pressure and autoimmune diseases such as lupus.

The important natures of CKD are:

• Chronic/long-term: People who suffer from CKD have to adhere to its treatment and lifestyle changes for the rest of their lives.

• Progressive: CKD has five stages, with stage 5 being the end stage –  that is when your kidney fails and your doctor might put you on dialysis. One of the goals of CKD treatment is to stop your CKD from progressing further and preserve as much kidney function as possible.

Image credit: https://choosingdialysis.org/YourKidneyHealth/ChronicKidneyDisease.aspx

• Irreversible: To put it more bluntly, there is no cure for CKD. You cannot reverse the damage that has already happened to your kidney, but treatment can help relieve the symptoms and stop it getting worse.

Diabetic kidney disease usually causes no symptoms until at least 75% of your kidneys' function is lost, and people who have the condition often produce normal amounts of urine. Although the urine is being formed, it does not contain sufficient amounts of the body's waste products because your kidney has already lost the ability to filter wastes. 

"Kidney Disease" by National Institutes of Health (NIH) is marked with CC PDM 1.0

To detect diabetic kidney disease, your doctor relies on tests that measure protein levels in the urine and blood tests to evaluate the level of your kidney function. Why measure protein levels in the urine, you ask? Well, when the kidneys are working normally, they prevent protein from leaking into the urine, so finding protein in the urine is a sign that the kidneys are in trouble. Blood tests are conducted to mainly evaluate the level of creatinine in your blood. If your creatinine concentration in the blood goes up, it reflects your kidney function has declined.

As time goes by, kidney disease may start to wreak havoc on your overall health. Patients with CKD may develop swelling of the feet, ankles, or legs. This is because when your kidney goes out of business, there is extra fluid and sodium stays in your blood circulation, leading to swelling. 

Patients with CKD also often develop high blood pressure, blood chemistry (electrolyte) abnormalities such as a high potassium concentration, anemia (a decrease in red blood cells, which can cause fatigue and other symptoms), and bone disease. When the kidney fails, they may develop a condition known as uremia, this is when too much urea (a waste product) stays in the blood, when it should be expelled from the body by the kidney. Uremia can lead to the following symptoms:

• loss of appetite, 

• increased sleepiness, 

• nausea, 

• vomiting, 

• confusion, 

• difficulty thinking

How does diabetes cause kidney disease?

High blood sugar level can damage the blood vessels in your kidneys. When the blood vessels are damaged, they don’t work as well. Many people with diabetes also develop high blood pressure, which can also damage your kidneys. You are also more likely to develop kidney disease if you have diabetes and

• smoke

• don’t follow your diabetes eating plan

• eat foods high in salt

• are not physically active

• are overweight

• have heart disease

• have a family history of kidney failure

End stage renal failure 

When your CKD progresses to stage 5, your kidney functions at only less than 15 percent. They can no longer keep up with your body’s needs, and a dialysis or kidney transplantation is needed. With the advancement in medicine today, kidney failure is no longer the end of the world. That being said, there are many inconveniences and side effects that can come along with dialysis and kidney transplantation, such as risks of infection and lifelong medications use. These procedures also come with a hefty price tag – the cost of haemodialysis is RM39,790 yearly, for example.

Could it be my diabetes medications that harm my kidney?

A misconception about diabetic kidney disease is that patients often thought their kidney disease is a result of the side effects of the medications. As a result, they stop their medications voluntarily without consulting a doctor (or worse still, looking for alternative treatment that is not proven to be effective and safe). The medications for diabetes, if taken according to your doctor’s instructions, will not result in kidney damage. 

If anything, the more likely cause of kidney damage in diabetes patients is when their blood sugar is not controlled properly over a period of time. By not taking your diabetes medications, you actually set yourself up for kidney damage. 

A possible explanation for such a myth might be this: When kidney damage is observed in a diabetes patient, the doctor may stop some of the diabetes medications. This is a standard practice regardless of whether the medication is for diabetes or not – when your kidney is damaged, it does not filter medicine as effectively. By stopping the medication, the doctor tries to prevent medicine from building up in the patient’s body and results in drug overdose. It is NOT because the diabetes medications damage the kidney that the doctor removes them. 

With that being said, some medications, if taken long-term, can result in kidney damage. Some examples are the NSAIDs painkillers such as naproxen and ibuprofen, as well as certain antibiotics. Tell your healthcare provider about your kidney disease when being prescribed with these medications. Do not start or stop taking these medications without professional advice.

Keep your kidney healthy despite having diabetes

There are two best ways you can do to prevent or slow down diabetic kidney disease: (i) control your blood sugar level and (ii) control your blood pressure. Different people have different targets for blood sugar level and blood pressure that they should achieve. Ask your doctor what your goals should be. Reaching your goal numbers will help you protect your kidneys.

Control your blood sugar level

Your healthcare provider will test your HbA1c every 3 months. HbA1c is a blood test that shows your blood sugar level over the past 3 months, and you do not need to be fasting prior to the test. You can get this test at any clinics or pharmacies. The A1C goal for many people with diabetes is below 7%, nonetheless you should ask your doctor what your target HbA1c should be. Besides, also ask how often you should check your blood glucose level. 

Needless to say, to effectively control your blood sugar level, you should always follow your doctor’s instructions on taking your diabetes medications or injecting insulin, and attend for regular health check-ups.

Keep that blood pressure reading nice and pretty

High blood pressure makes your heart work too hard, as well as destroying the blood vessels at your kidney. It can cause heart attack, stroke, and kidney disease. It is very common for diabetic patients to also develop high blood pressure. A blood pressure reading below 130/80 is the recommended goal for most people with diabetic kidney disease, especially if you have more than 300 mg of albumin (protein) in your urine per day. 

Besides knowing your blood pressure target and checking it regularly, you should always remember to take your blood pressure medications as instructed. Two types of blood pressure medicines, ACE inhibitors and ARBs, play a special role in protecting your kidneys. If you have diabetes and high blood pressure, it is very likely that you are taking either one of those medications. The names of these medicines end in –pril or –sartan. In fact, the kidney benefits of ACE inhibitors and ARBs are so robust that doctors sometimes prescribe them for people with diabetic kidney disease who have normal blood pressure. 

Note: ACE inhibitors and ARBs are not safe for women who are pregnant.

Develop or maintain healthy lifestyle habits

Healthy lifestyle habits are equally important to ensure your diabetes is well-controlled and keep your kidney healthy. You know the drill:

• Stop smoking

• Limit your alcohol consumption under 14 alcohol units a week

• Work with a dietitian to develop a diabetes meal plan and limit salt and sodium

• Make physical activity part of your routine

• Stay at or get to a healthy weight

• Get enough sleep. Aim for 7 to 8 hours of sleep each night

If you have diabetic kidney disease, we hope you know that you are not alone in this. For more supporting services, you may refer to the National Kidney Foundation (NKF) Malaysia’s website.

If you are a kidney disease patient on haemodialysis and wish to join a patient support group, you can find more details here. To get MOH’s subsidy for dialysis, check out for more information here.

References

1. The National Institute of Diabetes and Digestive and Kidney Diseases - Diabetic Kidney Disease

2. NHS UK - Chronic Kidney Disease (Treatment)

3. National Kidney Foundation - Diabetes - A Major Risk Factor for Kidney Disease

4. UpToDate - Patient education: Chronic kidney disease (Beyond the Basics)

5. UpToDate - Patient education: Diabetic kidney disease (Beyond the Basics)

Cover image credit: "diabetic kidney disease" by Srushti.p is licensed under CC BY-ND 2.0

Written by

Ms Joyce Toh