Dr. Roach: Careful control of diabetes is necessary to stave off further kidney disease
Dear Dr. Roach: For the past several years, I have had an abnormal creatinine reading. The readings range from 2.2 to 2.9. Every time I go to the doctor, I get a different reading. He is very cautious and wants to see me every month, which is economically very difficult. I have had Type 2 diabetes but haven’t needed medicine since I lost about 40 pounds after my knee surgery, and I have kept it off. My cardiologist says the damage was done to my kidneys when I had the diabetes and is going to stay. I had sonograms of my kidneys, and they came back fine. I keep myself hydrated and stay away from salt. Proteins are a little tougher. I see the kidney specialist every three months and have my blood taken. My question is: Do we consider the readings, or do we consider how the patient looks and feels overall? Do I have to be worried about eventually needing dialysis? I am 76 years old and feel fine.
Dear W.: Diabetes, both Type 1 and Type 2, is the leading cause of kidney disease in North America, and the damage done usually is permanent, even if the diabetes is controlled. However, progression can be slowed dramatically with good care.
Periodically checking the creatinine level, which is the most common method of monitoring kidney function, is essential; however, checking every month sounds like it might be more often than strictly necessary, as long as the readings are not consistently increasing. To slow progression of kidney disease, exercise careful control of high blood pressure in addition to the diabetes. If there is protein in the urine, the ACE inhibitors and angiotensin receptor blockers are more effective than other treatments in preventing progression to dialysis. Salt restriction helps blood pressure control in most people.
Protein restriction is probably less key than once thought, especially if BP and diabetes are well-controlled. But plant-based diets lead to slower progression than animal-based diets.
The decision to proceed to dialysis depends on how you look and feel, not on your numbers. But taking as much control as you can now will help keep your kidneys going for years, and hopefully decades.
Dear Dr. Roach: Should your blood pressure go higher as you age? Is the top number or the bottom more important?
Dear J.S.: Both the systolic (top number) and diastolic blood pressures are important, and the difference between may be important (for example, a blood pressure of 160/60 is more worrisome than 160/85). Blood pressure does go up with age, but even in people over 60, the recommendation is still to get the BP down below 150, and I try to aim for 140 if there aren’t too many side effects. It often takes several tries to find a regimen that gets the blood pressure where it should be without affecting quality of life.
Email questions to ToYourGoodHealth@med.cornell.edu.