In the last issue of the Kidney Corner, we discussed the stages of chronic kidney disease.
To recap, CKD is graded from Stage 1 (the least severe) to Stage 5 (the most severe level, frequently requiring dialysis). What are the underlying illnesses or conditions that can cause this type of decrease in kidney function?
The most common cause of kidney disease is diabetes, also called diabetes mellitus. There are two forms of diabetes mellitus: Type 1, which is due to a deficiency in insulin production by the pancreas (this form is relatively rare in Native American patients); and Type 2, which is more common, tends to begin later in life, and is associated with being overweight in many, but not all, patients.
Type 2 diabetes results from a decreased ability of cells to respond to insulin, rather than an absolute deficiency of this hormone. The resulting high glucose levels cause damage to various organs including the filtering cells of the kidneys, resulting in damage to the filtering membrane of the kidneys.
This causes loss of protein in the urine and subsequently scarring of the microscopic filters, gradually reducing the ability of the kidneys to excrete toxins from the body. About 40 percent of patients with end-stage renal disease on dialysis have diabetes, and the prevalence of diabetes appears to be increasing in the American population.
It is important that we find ways to stem this epidemic of diabetes by improving our lifestyles: increasing our level of activity and avoiding being overweight by restricting calories when appropriate.
The second most common cause of CKD is hypertension, or high blood pressure. Careful attention to the treatment of this “silent killer” can help prevent the onset and progression of CKD (as well as avoiding other health complications, such as heart attacks and strokes).
Again, treatment involves attention to lifestyle — exercise, avoiding salt and excess weight gain — and often medications. If you have high blood pressure, don’t be tempted to ignore it!
Inflammation of the kidney, called glomerulonephritis, is a less common but potentially treatable cause of kidney failure. Some forms of GN, most notably a form called IgA nephropathy, are more common in Native American patients.
Like other causes of CKD, GN can also be “silent” and cause no symptoms, but it’s sometimes detected by the presence of associated high blood pressure, swollen ankles, or protein in the urine detected by lab tests.
Other causes of chronic kidney disease include various medications — including some over-the-counter anti-inflammatory medicines — infections, obstruction of urine due to prostate enlargement, and some less-common hereditary conditions.
We will continue to discuss each of these periodically in the Kidney Corner.
So with all these risks to the kidneys, how can you tell whether you have a problem that could progress to severe kidney failure? Simple screening tests can usually detect CKD fairly easily. For most people, this screening would include a blood pressure check, a blood test for creatinine, which is easily performed in all medical laboratories, and a urine test for protein.
I would recommended that you have these three tests performed if you have known diabetes, hypertension, a family history of CKD, or if you have any other known medical condition which increases your risk for CKD. I wish you good health!