Most people don’t really think about their kidneys, but people with type 1 diabetes need to pay special attention to kidney health. Kidney disease is a common complication of type 1 diabetes. Up to forty percent of patients with type 1 diabetes have some form of kidney disease, but it is possible to prevent or delay the progression through good blood glucose control and good blood pressure control. In addition, many actions can be taken to promote general kidney health such as eating right, exercise, and more. Dr. Elaine Ku is a pediatric and adult nephrologist who focuses her research on people with type 1 diabetes from a kidney perspective. At this year’s Bay Area Diabetes Summit, she shared her tips for monitoring the health of your kidneys in relation to diabetes. Here are key pointers from Dr. Ku’s talk:
What do the kidneys do?
- Kidneys filter the blood
- They remove waste products that the body generates on a day to day basis
- They remove excess salt, metabolytes, and water
- The kidneys also regulate blood pressure ( play a critical role, not just heart)
Why do the kidneys come into play with diabetes?
High glucose levels can increase the amount of blood delivered to your kidney that needs to be filtered. If exposed to chronically high glucose levels, the kidneys must work harder than they should. This can lead to a leakage of protein and decreased kidney function. Over time, the kidneys no longer filter and clean waste products in the blood as well as they used to. The body may also make less urine over time.
How do I care for my kidneys?
To keep kidneys as healthy as possible, follow these guidelines:
- Maintain a healthy blood pressure
- Maintain a healthy weight
- Eat healthy
- Lower salt intake
- Limit Alcohol
- Avoid smoking
- Avoid certain medications
- See your doctor regularly
- Manage your diabetes
Maintain a healthy blood pressure
Normal blood pressure levels vary with age, but for anyone older than 13, a blood pressure less than 120/80 mm Hg is normal. Blood pressure between 120-130/80-90 mm Hg is elevated, and anything greater than or equal to 130/80 mm Hg is high. These guidelines have recently been changed. The cutoff for high blood pressure used to be 140/90 mm Hg, but studies have shown that lower blood pressure improves cardiovascular health.
People with type 1 diabetes should have their blood pressure checked at every doctor’s visit (around every 3 months). One-time elevations in blood pressure may be due to isolated reasons: stress, rushing to the doctor’s office, or the “White Coat Effect” (being nervous about seeing a doctor). Here are some suggestions for avoiding isolated high readings:
- Avoid caffeine before your visit
- Avoid vigorous exercise right before your appointment
- Stay calm and relaxed
- Get a home blood pressure cuff and take blood pressure readings in your regular environment to establish your usual bp range
If an elevated blood pressure level is recording three or more times, a more thorough evaluation is recommended. Doctors may send the patient home with a 24 hour blood pressure monitors which automatically read blood pressure very 20 minutes during the day, and every 30 minutes at night. Blood pressure often drops during the night, while sleeping, so elevated blood pressure during sleep may be a concern.
Smoking raises systolic blood pressure (the top number in your reading) by 2-3 points
Chronic alcohol use is associate with higher blood pressure
The American Heart Association recommends 150 minutes of moderate physical activity each week. Remember: not every activity counts as exercise; you must actually work up a sweat to have it count!
Lower your salt intake
The American Heart Association recommends that adults consume no more than 2400 mg sodium, or one teaspoon of salt per day. The normal American diet contains between 5000-6000 mg of salt per day, so this is a difficult target to achieve. There are about 1100 mg sodium in a single McDonald’s Big Mac! The AHA recommends the DASH diet for low blood pressure.
Avoid certain medications
Certain OTC pain medications can have kidney-related side effects. Limit the chronic use of:
Occasional, one-time use is allowed, but chronic use can damage kidneys over time.
See your doctor regularly
Urine tests for kidney function are recommended once per year in people with type 1 diabetes, beginning about five years after diagnosis (kidney issues rarely develop right after diagnosis). The urine test will test for a protein called albumin. A first morning urine sample is recommended. In a subset of people, the effects of gravity may push some of the protein out of the urine when they walk around during the day. So the test may not be accurate if taken later in the day.
If the test results are positive for albumin, doctors may ask patients to retake the test in the morning. Don’t take the urine test if you are sick, had a fever, are menstruating, or have exercised a lot the day before. These can also cause protein to leak out of the urine. Occasionally, the doctor may tell the patient to collect all urine produced in a 24-hour period. This tests for all the protein that has leaked out during the 24-hour period.
Another test to monitor kidney health is a blood test for serum creatinine. The higher the serum creatinine level, the lower the kidney function. This test should be done starting five years after diagnosis, then every year thereafter. An alternative to this test is a new test called cystsatin C. This test is more sensitive. It picks up abnormalities in kidney function much earlier than the serum creatinine test.
Manage your diabetes
Diabetic kidney disease can be prevented by keeping blood glucose in your target range. The good news is that cgm monitoring and insulin pump therapy have revolutionize diabetes management. Consequently, kidney complications have decreased in frequency over the last decade. Over time, medical care teams have been able to delay the kidney complications of diabetes over time, using good glucose control. Also, less albumin is being detected in the urine in the early years after a diabetes diagnosis. With tight glucose management, medical teams are delaying the onset of protein in the urine.
Dr. Elaine Ku, MD. MAS is an Assistant Professor with the Departments of Medicine and Pediatrics, Divisions of Nephrology and Pediatric Nephrology, at UCSF.
Disclaimer: The discussion has been condensed and edited for clarity. The information contained in this post is not intended to constitute medical advice. Individuals with T1D should consult with their medical professionals about the screening tests and procedures they need to monitor and manage their diabetes.