Nearly 37 million Americans, or 15%, have chronic kidney disease (CKD), but 9 in 10 adults with the condition are not aware of their diagnosis. A recent study from Stanford University found that
What should primary care providers be doing differently?
The current standard of care is to screen people with underlying conditions that put them at higher risk of developing CKD, most commonly diabetes and hypertension. That’s why the American Diabetes Association recommends annual screening for CKD in patients with type 1 diabetes as well as those with type 2 diabetes.
And the American Heart Association (AHA) released an advisory last year that defined cardiovascular-kidney-metabolic (CKM) syndrome, a constellation of conditions that often occur together: obesity, diabetes, CKD, and cardiovascular disease. They propose a staged approach to identifying and monitoring CKM throughout the lifespan, which includes regular monitoring of the urine albumin-creatinine ratio in patients who have developed diabetes, hypertension, metabolic syndrome, or any signs of kidney disease.
But despite recognition from the subspecialty professional societies of the importance of screening persons with risk factors — additional conditions are obesity and family history of CKD — real-world implementation lags.
Sylvia Rosas, MD, is a nephrologist and associate professor of medicine at Harvard University in Cambridge, Massachusetts, who also serves as president of the National Kidney Foundation. In an interview with this news organization, she cited several alarming facts about the state of CKD screening in the United States.
“Of people with diabetes who have insurance, only 40% get both the glomerular filtration rate (GFR) and the albumin performed, and for those who have hypertension, only 10%,” Dr. Rosas said. She is referring to a urine spot test that measures the amount of albumin in the urine, which is then paired with a serum measurement of creatinine to estimate the glomerular filtration rate. Both tests are needed to detect the asymptomatic stages of CKD, because the presence of albumin in the urine usually precedes drops in the GFR, which indicates more serious disease.
Dr. Rosas said she is frustrated by the low rate of testing compared with other commonly recommended preventive screenings, given the low cost and simplicity of assessment. Serum creatinine often is obtained as part of a routine chemistry panel, and the albumin test requires a single spot urine test. Yet, in 2018, 61% of US adults aged 50-75 years had received a colonoscopy in the past 10 years. Compared with the high price and inconvenience of undergoing colonoscopy, Dr. Rosas has trouble believing that “we cannot get more than 40% of people [with diabetes] to pee in a cup.”
But the biggest issue is that if people with risk factors don’t get screened before they develop symptoms of CKD, it is often too late to avoid dialysis or the need for transplantation.
The early warning symptoms are few, according to Nisha Bansal, MD, a professor in the department of nephrology at the University of Washington in Seattle. “New hypertension is a really important early sign,” Dr. Bansal said. “We know kidney disease almost certainly causes hypertension, so I would definitely think about screening for kidney disease.” Other findings on exam are the appearance of new edema or signs of fluid retention in the hands or around the eyes, along with findings in the urine of albumin, protein, or blood.
But most patients don’t have any symptoms in the early stages, and they can be nonspecific. “It is fatigue and some nausea,” Dr. Rosas said. “It’s only way at the end that you start vomiting, get itchy, or have hiccups.” Data from the Centers for Disease Control and Prevention have shown that over one third of patients at high risk for kidney failure are unaware of their disease. According to Dr. Rosas, these are patients who often receive the diagnosis of CKD and start dialysis the same day.