Protecting our Kidneys

David Mendosa Health Guide August 20, 2007
  • Our doctors commonly prescribe ACE inhibitors and ARBs when we have high blood pressure. They help protect our hearts.

     

    But I've never had high blood pressure. The nurse had just measured my blood pressure as 100 over 60, when my doctor prescribed these drugs anyway.

     

    Was I ever surprised! Why do I need to take still another drug?

     

    Because they help to decrease the risk of diabetes-related injury to the kidneys, he told me. They selectively reduce the pressure on the artery coming from the filtering unit of the kidney compared with that going to it.

     

    I knew that people with diabetes are at risk for kidney disease. But I never imagined that with my tight control he would consider me at risk too.

     

    So even though I hadn't ever heard before that all of us with diabetes should take an ACE inhibitor or an ARB, I went along with my doctor's recommendation. I did check with endos and Certified Diabetes Educators whom I know and respect. They confirmed what my doctor had told me.

     

    ACE inhibitors are angiotensin-converting enzyme inhibitors. ARBs are angiotensin receptor blockers. Both types of drugs help us keep kidney problems at bay as well as control high blood pressure.

     

    Still, they have at least two major differences. A common side effect of ACE inhibitors is a persistent dry cough, while that's not a common effect of an ARB.

     

    Like many if not most people talking an ACE inhibitor, I got that side effect. I hated it.

     

    So my doctor switched me to an ARB. He switched me to the least expensive one in the formulary of my health insurance plan. I cut the cost further by asking him to prescribe double the strength that he wanted me to take.

     

    Why? So I could cut the pill in half and save almost that much.

     

    (Note: Not all pills can be effectively split. Ask your doctor before cutting pills.)

     

    Nevertheless, I ran headlong into the other major difference from ACE inhibitors, several of which are now available in generic versions that are much less expensive than brand name pills. No ARBs are yet available in this country as generics.

     

    Consequently, I fell into Medicare's infamous donut hole with half the year left to go. This is the phase of coverage in which we have to bear all of the costs of our prescriptions. Medicare likes to call it by the duller name "coverage gap."

     

    By whatever name, the additional cost of the ARB that I'm taking is almost $200 per month. I hope that my good health is worth it.

     

    But I am hopeful that I won't have to take an ARB much longer. The damage to our kidneys may be the result of AGEs, which I have written about here several times, most recently in April. These advanced glycation end products are glycotoxins.

     

    AGEs are of special importance for those of us who have diabetes. "AGEs are excreted by the kidneys, whose capacity may be easily exceeded," Dr. Helen Vlassara, professor of medicine at the Mount Sinai School of Medicine and the world's leading authority on AGEs, told me when I interviewed her. That's especially true "in the presence of renal disease, diabetes, or high AGE intake."

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    But I recently had the opportunity to have my AGEs level tested, and it was normal. I plan a future article about that useful test.

     

    "I suspect that the renal damage occurring through the renin system is triggered by AGEs," Karen LaVine, my favorite CDE, tells me. "That is why ACEi/ARBs have shown significant benefit to people with diabetes. ACEi/ARBs affect the renin system. I also suspect that we'll eventually find out that the ACEi/ARBS aren't needed if we avoid AGEs and keep our thiamine/benfotiamine levels up."

     

    Benfotiamine is a form of vitamin B1 that I wrote about here. Karen reviewed the new evidence that low levels of plasma thiamine in people with diabetes is linked to a marker of vascular disease.

    "As soon as research bears out what I'm hoping is true, I'd drop the ARB that you are taking like a hot potato," Karen also suggests. Especially since I almost passed out today from low blood pressure, I am looking forward to that day.