Protecting Kidneys in People with Diabetes
Let’s start by dispelling a common myth: metformin, which is the most commonly used diabetes medication, does not cause kidney damage. However, in patients with diabetes who develop kidney damage, we may need to decrease the dose of metformin, or stop it altogether, to prevent side effects occurring at that point of time.
In the same way, if you have diabetes and develop an acute illness, it is important to temporarily discontinue certain medications like painkillers, blood pressure medications and diabetes medications that are collectively called sick day medications. And your doctor or pharmacist can let you know if you are on any of these.
People with diabetes are unfortunately prone to a wide array of complications. One of the commonest complications is kidney damage, which when progresses, can lead to dialysis or even death.
Kidneys are like a filter, or sieve, in the body. Glucose, or sugar, is a large molecule. And when presented in large quantities, can affect the fine mesh of this sieve, as can uncontrolled blood pressure. As a result, your kidneys may start leaking protein into the urine, called microalbuminuria, which is an early sign of kidney damage. In the same way, your blood creatinine levels may start rising, suggestive of worsening kidney function.
If appropriate steps are taken in a timely manner, this damage can be halted and the complications prevented. Your doctor may start you on a blood pressure medication to protect your kidneys, even if your blood pressure is not high. In the same way, you might be started on a cholesterol medication too.
There is a new class of diabetes medications that help lower blood sugars by dumping the excess sugars in the urine. These have been shown to reduce the rate of progression to dialysis, and even the risk of death due to kidney failure by as much as 30%. These agents work by causing reduction of blood pressure in the blood vessels that feed into the kidneys, thereby reducing the strain on the filters.
Studies show that when used effectively, these agents can delay kidney failure, and might even be effective in those without diabetes. These agents also help reduce the risk of heart failure and cardiovascular disease.
Adequate diabetes management requires not just controlling blood sugars, but also reducing the risk of complications of diabetes. Hence, for people with diabetes, it is important to avoid medications that can damage the kidneys, and one should preferably use medications that can help protect the kidneys, especially if one has protein leaking into the urine or rising creatinine levels.
Presenter: Dr. Akshay Jain, Endocrinologist, Surrey, BC
Local Practitioners: Endocrinologist