Updated 7/3/2020
I’ve lectured and written a lot about the heart and the brain over the years, but I regret that I haven’t focused enough attention on the kidneys. In honor of March being National Kidney month, I joined up with the National Kidney Foundation (NKF) to contribute this post. Among the various patients I see in my practice, those with chronic kidney disease are some of the sickest, most debilitated patients who require high levels of intensive care and monitoring. I also updated this post during Covid-19 where kidney disease is turning out to be a major risk factor for serious Covid-19 complications.
Often family members have to regularly take time off work to transport kidney patients for procedures like dialysis or for frequent blood tests. The tragedy is that most of these cases could have been prevented. Let’s first gain a better understanding of what the kidneys do and how we can screen for problems, and then we’ll discuss why kidney disease is so common in South Asians.
KIDNEY 101
Where are your kidneys and what do they do? The kidneys are in your lower back just below the rib cage. They are the size of your fist and weigh about five ounces. Most people are born with two kidneys, but you only need one. The kidneys filter 200 liters of blood every single day, keeping the blood minerals in balance by removing toxins, wastes and water. This is the job the kidneys are known for, but did you know that the kidneys do a lot more? The kidneys also help regulate blood pressure and fluid levels, control the production of red blood cells, and activate vitamin D for strong, healthy bones. When the kidneys fail, people must go on dialysis or receive a kidney transplant to survive. Unlike most other organs, because you only need one kidney, one of your kidneys can be donated while still living.
GET TESTED
If you’re at risk for kidney disease, it’s important to get your kidneys checked during your annual physical. Be sure to speak up and request these two simple tests to check for kidney disease:
- A urine test for albumin, a type of protein: protein in the urine is one of the earliest signs of kidney damage. When there is too much protein in the urine, it means that the kidneys’ filters are damaged and are starting to leak protein.
- A blood test for creatinine: creatinine is a waste product (from muscle metabolism) that is removed by the kidney. Creatinine level is used to calculate your estimated glomerular filtration rate (eGFR). The eGFR reflects how well the kidneys are filtering wastes from the blood.
KIDNEY-HEART CONNECTION
Metabolic syndrome, an insulin resistant condition that is a major global risk factor for heart disease, increases kidney disease by 2.5-fold and doubles the risk of microalbuminuria (protein in the urine). Kidney disease appears long before high blood pressure or diabetes in metabolic syndrome and the presence of microalbumin in the urine is an indicator of increased heart disease risk.
PREVENT OR STOP KIDNEY DISEASE
Testing and prevention go hand-in-hand and knowing how to keep your kidneys healthy is essential to preventing or stopping kidney disease. All of the essential things you do for heart health can apply to kidney health as well, including the following:
- exercise regularly and check out my exercise post here for guidelines
- eat fresh, unprocessed, nutrient-dense whole foods
- maintain a healthy weight
- quit (or don’t start) smoking
- control high blood pressure and diabetes – track both and take any prescribed medications consistently. Read my blood pressure post here for details.
- beware of medications and supplements that can affect your kidneys. for example, pain killers called nsaids (advil, motrin, etc.) taken chronically can damage the kidneys. talk to your doctor and pharmacist to learn the impact of your medications and supplements on your kidneys.
ETHNICITY AND RISK
Certain ethnic groups like African Americans and Asian Americans are at higher risk for kidney disease than Caucasians. Blacks suffer kidney failure at a rate that’s 3 times greater than Caucasians as discussed here and Asian Americans, particularly Asian Indians, are also at higher risk as shown here.
If you belong to a high risk ethnic group, be sure to especially monitor and control major contributing conditions to heart disease like high blood pressure and diabetes. Be sure to not only monitor your own kidney function if you have these risks, but keep track of your family’s kidney function as well. I’ve seen many older patients from India and other countries where preventive health is not a part of culture who were not getting their kidney tests done annually despite having risks like high blood pressure and diabetes.
For more information about the kidneys and kidney disease, visit the National Kidney Foundation’s website at www.kidney.org or contact the Patient Information Helpline: NKFcares@kidney.org or call 1-855-653-2273.