With 10 to 13 percent of the adult population battling chronic kidney disease (CKD), nephrologist Dr. Adrian Sawyer says people should want to know if they have any risk factors that could predispose them to kidney disease, which include high blood pressure, diabetes, and a family history of kidney disease. And particularly females with lupus, he said, should want to be aware, as the disease is common in black people, and as such, they are at risk for kidney failure.
Sawyer said providers of health care should routinely undertake screening for kidney disease in people at risk, which include adult onset and type 1 diabetes; people classified as overweight to obese, which he said is a significant national problem; and people with high blood pressure (hypertension) or a family history of hypertension.
At risk screenings, he said, should also be done on people with a single kidney; persons with genetic predispositions such as polycystic kidneys; patients with diseases known to affect the kidneys such as lupus, rheumatoid arthritis, and sickle cell disease; and patients that have been hospitalized in the intensive care unit, as approximately 40 percent will have had some form of acute kidney injury, which puts them at risk for delayed chronic CKD.
Cancer patients should also be screened as he said an increasing number of chemotherapy agents have been associated with kidney injury.
As Kidney Month is recognized, and the second Thursday in the month – March 12, recognized as World Kidney Day, the nephrologist urges people to ensure their doctor orders the appropriate tests to make the determination, which include a blood test, urine test, blood pressure check, and their blood checked for diabetes. And if they test positive, to ensure they are referred to a kidney specialist, because the stages of kidney failure, he said, requires specialized treatment to slow the progression to dialysis or transplant.
With the focus on kidneys this month, it’s an initiative that is a global campaign aimed to increase awareness of the importance of kidney health and reducing the impact of kidney disease, a non-communicable disease (NCD) and its associated problems worldwide. Every year since inception, there has been specified focus on certain aspects of kidney disease with designated themes. This year’s theme questions the importance of kidney disease.
“CKD is a progressive loss of organ function over a period of months or years. CKD is common, and globally affects between eight and 10 percent of the adult population. It is progressive and eventually leads to kidney failure, requiring hemodialysis or kidney transplantation for support of life and kidney replacement treatments,” said the kidney specialist. “The prevalence and incidence of CKD is increasing worldwide, mostly related to concurrent increase in the epidemic of obesity and diabetes, the latter of which is the single largest aetiologic cause of end stage kidney disease, accounting for 45 percent in the United States. People of African ancestry have a four-fold increased occurrence of CKD and ESRD (end stage renal disease) compared to Caucasians.”
Sawyer said CKD is usually an irreversible disease with severity occurring over time, is associated with increased co-morbidities and adverse outcomes and contributes to the global burden of non-communicable disease. He said patients with stage five disease have short life expectancy without kidney replacement treatment (dialysis/transplantation).
The nephrologist said CKD increases the risk of premature death from cardiovascular disease (heart attacks, strokes, heart failure, sudden cardiac death) and less commonly associated infection risks. And that a 35-to-45-year-old patient with CKD has a 10-to-20-fold increased risk of death over one to two decades, compared to non-chronic kidney disease and normal kidney function populations.
While incurable, the doctor said early detection and treatment of risk factors and associated co-morbid conditions such as diabetes, high blood pressure, and abnormal cholesterol levels, can slow down the progression of the trajectory to dialysis/transplantation considerably.
He also cited early detection, education and institution of prevention measures such as the modification of lifestyle, diet and exercise, with weight reduction, along with appropriate treatment of co-morbid conditions as important to slowing down the progression.
Function of kidneys
Normally, people have two kidneys. According to the doctor, a single kidney occurs in approximately one in 1,000 live births, placing these people at some risk for future kidney damage, mostly related to accidental trauma and exposure to future impact of acquired disease such as diabetes, hypertension, glomerular and interstitial diseases, which together he said account for more than 80 percent of the causes of CKD.
In the absence of the noted diseases, Sawyer said people with one kidney maintain normal kidney function and have normal life expectancy.
Kidneys have three anatomical compartments that are functionally interdependent. He said severe damage in one compartment induces secondary changes in the other compartments that eventually combine to progress to CKD stages to ESRD. And that obstructive blood vessel disease of the arteries supplying blood to the kidneys, such as atherosclerosis resulting from diabetes, hypertension and elevated abnormal cholesterol profile components can eventually lead to degenerative changes that eventually result in ESRD.
Sawyer said that systemic lupus erythematosus (SLE) is a multi-system disease, which eventually affects the kidneys in 60 to 70 percent of females of African ancestry and is more severe, commonly targets the glomeruli along with the interstitial compartments simultaneously or sequentially, which, when present, significantly influence treatment with medications that have serious adverse effects.
Diabetes, which is the single largest cause worldwide of ESRD, causes damage to both the glomerular and interstitial compartments.
Chronic kidney disease
To be classified, CKD medical professionals use three parameters to identify categories: estimated glomerular filtration rate (eGFR), assessment of albumin quantity in urine, and specific disease category.
The main function of the kidneys is to filter blood through the glomerulus. GFR is a measure of this function and estimating equations he said have been developed based on actual measurements done in humans using a standardized reference calibrated measurement of a product excreted from the body, essentially more than 90 percent, blood creatinine levels. Using, gender, ethnicity, and age along with blood creatinine, these equations classify eGFR in five stages.
He said currently, only two local laboratories use a standardized calibrated method for determination of blood creatinine levels in the kidney function panel test.
Specific disease category: diabetes, hypertension, glomerular diseases (glomerulonephritis), polycystic kidney diseases, etc. “The thrust of the World Kidney Day campaign for 2020 focuses on detection of kidney disease and prevention. Successful approaches or strategies for achieving this goal require the integration of education provision to the public, providers of medical care, public health agencies and governments; implementation of policies directed to detection and prevention and provision of adequate funding,” said Sawyer. “The first objective is attained by public and medical health provider education programs, which will result in earlier referral to kidney specialists, who subsequently engage in prevention medical strategies to impede a generally progressive disease culminating in dialysis or kidney transplantation.”
The performance of blood and urine testing for creatinine and protein, respectively, he said, achieves the objectives required. He explains that the kidney function panel will provide the eGFR, and that only three private laboratories have the capability using a standardized methodology.
The average cost of a kidney function panel ranges from $75 to $85; more specific urine protein estimation that would be requested by a nephrologist, range from $124 to $139.
Prevention measures/strategies are divided into three groups: primary preventative strategies, secondary prevention strategies, and tertiary prevention strategies.
In primary prevention, the goal is averting kidney disease. Interventions involve lifestyle modifications with moderate physical activity, low sodium diet with reduced protein intake, managing obesity and improving blood pressure control and blood glucose control in people at risk. Identifying genetic risk factors and ensuring adequate hydration.
Secondary prevention strategies include: treating disease in early stages and slowing progression of disease. Managing blood pressure control to target levels, treating urine protein with specific drugs to reduce levels. Diet treatments with reduced sodium, protein, increased vegetarian-type, plant-based diets. And optimally, managing cholesterol abnormalities with appropriate medications, identifying and managing additional risk factors.
Tertiary prevention strategies include: goal-avoiding kidney failure/dialysis/transplantation to preserve remaining kidney function. Managing fluid retention and symptoms of kidney failure such as fatigue, anemia, bone disease, heart function (heart failure), avoidance of medications or medical interventions associated with kidney damage – NSAIDs (nonsteroidal anti-inflammatory drugs) Motrin, Advil and other drugs in the category; the use of antibiotics that have potential for kidney damage – Gentamicin, Fluroquinolones (Ciprofloxin), and long term use of gastric acid inhibitors such as Nexium and other drugs in the class. Treating associated cardiovascular risk factors, which are responsible for significant mortality; and once stage three CKD is established, more than 80 percent of patients will die of the complications before they reach dialysis/transplantation. The increased risk of death, said Sawyer, is approximately increased by 10-to-20 fold, compared to age-matched controls without kidney disease.
Sawyer said kidney replacement treatments (hemodialysis/kidney transplantation) are expensive and consume disproportionate budgetary expense for health care systems in high-, middle- and low-income countries.
In the United States, he said, the treatment of CKD is likely to exceed $48 billion per year, and the end stage kidney disease program consumes 6.7 percent of the total United States Medicare budget to care for less than one percent of the covered population.
“In low-and-middle income countries, long term dialysis/kidney transplantation is unaffordable,” said the doctor.
According to Sawyer, the global burden of chronic kidney disease (CKD) is estimated to exceed 800 million people.
“There has been minimal attention to measures related to prevention and detection of CKD. The current World Kidney Day campaign theme serves to bring attention to the public, medical providers and governments of the need to address detection and prevention,” said Sawyer.