Why you should care about your body’s “toxin filters”

We are blessed with two kidneys, each of which has one million filtering units called nephrons. The kidneys maintain the fluid and electrolyte composition of the body, acid-base balance, and excrete toxic compounds, including drugs. They also behave as an endocrine organ. Kidneys secrete hormones such as erythropoietin that stimulate the bone marrow to make red blood cells, and renin, which is essential in blood pressure regulation and conversion of Vitamin D into its active form to regulate bone and mineral metabolism.

Uncontrolled diabetes mellitus and hypertension (high blood pressure) can affect kidney structure and function. High blood sugar damages the filtering component of the nephron, resulting in mild to severe protein leak into the urine. This manifests as swelling in the feet and legs, eventually advancing to generalized swelling. High blood pressure directly damages the

kidney and leads to gradual loss of kidney function over time. Kidney health can be maintained by living a healthy lifestyle and making certain that one does not have diabetes mellitus and hypertension.

Chronic Kidney Disease: Prevention and Treatment

The prevalence of chronic kidney disease (CKD) in the general adult population in the United States was 14.8 percent in 2013-2016. Overall, CKD prevalence has remained relatively stable during the last two decades.

What is CKD? CKD occurs when the kidney is chronically damaged and loses function. Indicators of kidney damage are the presence of protein and red blood cells that are not usually found in the urine or structural changes such as multiple cysts in the kidney. Kidney damage, if significant and prolonged, can lead to loss of kidney function. Loss of kidney function results in the inability of the kidneys to regulate fluids, electrolytes and acid-base, and to stimulate red blood cell and active Vitamin D. The inability to excrete salt and water can result in fluid overload, which can cause hypertension and heart failure. The inability to synthesize the erythropoietin hormone can cause severe anemia. As renal failure advances, many unmeasured toxins accumulate in the body and cause loss of appetite and alteration of consciousness, a condition called uremia. Fortunately, thanks to advances in technology and transplantation, patients with advanced CKD can continue to live with the assistance of dialysis or a kidney transplant.

The major causes of CKD are diabetes mellitus (causes 45 percent of CKD cases) and hypertension (causes 27 percent of CKD cases). Both medical conditions can be treated with lifestyle modification and medications. There is a worldwide increase in diabetes mellitus as a result of an epidemic of obesity and a sedentary lifestyle. Weight loss, eating a low carbohydrate diet and regular exercise can control early and mild diabetes mellitus. The addition of oral medications and insulin is necessary for blood glucose control when lifestyle modification is not enough. Poorly controlled diabetes can cause kidney damage that is suggested by the presence of increased protein in the urine. Besides controlling the blood sugar, the addition of certain blood pressure medications called angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) can decrease proteinuria and delay the progression of CKD in diabetics. These medications can also control hypertension, which is another cause for the progression of CKD in diabetics. For someone who is diabetic with CKD, strict blood sugar control, weight loss and blood pressure control with ACEI/ARB and other antihypertensive medications will delay the progression of CKD.

The number of people with high blood pressure in the world has increased by 90 percent over the last four decades. This increase may reflect low consumption of fresh fruits and high consumption of sodium with rising body weight. Poorly controlled blood pressure causes CKD and causes stroke and heart disease. Blood pressure can be controlled with lifestyle modification that includes weight loss, exercise and a diet rich in nuts, fruits and vegetables. Relaxation techniques such as meditation and yoga have been shown to lower blood pressure. Medications are needed for blood pressure control when lifestyle modification does not normalize the blood pressure (normal systolic BP 120 mm Hg and diastolic BP 80 mm Hg). The majority of patients will have their blood pressure controlled with one or two medications (the latter can be taken as a single combination pill). Self-monitoring of blood pressure at home with an automated electronic device gives the most accurate results. Blood pressure should be taken two to three times each day after a couple of minutes of relaxation with the arm resting on a table or armrest at the level of the heart. Blood pressure recordings should be saved and brought to the physician’s office to assist them in making appropriate adjustments to the medication regimen.

The major causes of CKD are preventable and treatable. A major focus on lifestyle modification will either prevent or weaken the two major causes of CKD, namely diabetes and hypertension.

References:

1. United States Renal Data System Report 2018.

2. Mills KT et al. Global disparities of hypertension prevalence and control: A systematic analysis of population-based studies from 90 countries. Circulation 134: 441–450, 2016

3. Wright Jr. JT, et al. SPRINT Research Group: A randomized trial of intensive versus standard blood pressure control. N Engl J Med 2015; 373:2103-2116

Kenneth Abreo, MD, FASDIN, is vice chair of the Department of Medicine, and chief of the Nephrology and Hypertension Section at LSU Health Shreveport. Dr. Abreo serves as the director of the FMC Dialysis Center of Shreveport and South Bossier, and the Dialysis Clinics Inc. in Shreveport and North Shreveport. For more information or to make an appointment with the Nephrology and Hypertension Clinic at Ochsner LSU Health Shreveport Academic Medical Center, call 318-675-7403.