Blog Post

Kidney Healthcare: The Early Signs of Chronic Kidney Disease


In this follow-up to our Issue Brief on the importance of early diagnosis and documentation, we identify early signs of chronic kidney disease (CKD)—symptoms that are sometimes attributed to other conditions.


In our recent Issue Brief, “Kidney Disease Management: It Starts Early,” [1] we discussed the need for diagnosis and documentation of Stage 1-2 chronic kidney disease (CKD). In this follow-up, we’ll look at the early warning signs of CKD.

We know that diabetes and hypertension are the leading causes of CKD. It follows that patients being treated for these conditions should automatically be considered at risk for CKD. However, CKD can be present in patients without diabetes or hypertension. In fact:

Two new studies from the Johns Hopkins Bloomberg School of Public Health and the Chronic Kidney Disease Prognosis Consortium found that the presence of chronic kidney disease itself can be a strong indicator of the risk of death and end-stage renal disease (ESRD) even in patients without hypertension or diabetes. — “Chronic Kidney Disease a Warning Sign Independent of Hypertension or Diabetes,” [2] Johns Hopkins/Bloomberg School of Public Health

According to Dr. Joseph Vassalotti, Chief Medical Officer at the National Kidney Foundation (NKF), “There are a number of physical signs of kidney disease, but sometimes people attribute them to other conditions. This is one of the reasons why only 10% of people with chronic kidney disease know that they have it.”

That quote comes from a consumer-facing article published on the NKF website, “10 Signs You May Have Kidney Disease,” [3] from which the following list is derived:

  • Fatigue, low energy, trouble concentrating—A decrease in kidney function can result in a buildup of toxins and impurities in the blood. Anemia, another complication of CKD, can also cause weakness and fatigue.
  • Difficulty sleeping—This can indicate that toxins are staying in the blood rather than being filtered out by the kidneys. Sleep apnea is also more common in people with CKD than in the general population.
  • Dry and itchy skin—This can be a sign that the kidneys are having difficulty maintaining the right balance of minerals and nutrients in the blood.
  • A need to urinate more often—Damage to the kidney filters can cause an increase in the urge to urinate. (It can also be a sign of urinary tract infection or enlarged prostate.)
  • Blood in the urine (hematuria)—Healthy kidneys will retain blood cells in the body while filtering impurities, but when damaged can allow blood cells to “leak” into the urine. (Blood in the urine can also indicate tumors, kidney stones, and infections.)
  • Foam in urine—Excessive bubbles in the urine indicate the presence of protein in the urine.
  • Persistent puffiness around the eyes—This can be caused by large amounts of protein in the urine, an early sign that the kidneys have been damaged.
  • Swollen feet or ankles—Swelling in the feet and ankles can be caused by sodium retention, indicating decreased kidney function. (This can also be a sign of heart disease, liver disease, and chronic venous insufficiency.)
  • Poor appetite—This can have several causes, but a buildup of toxins in the blood due to decreased kidney function is one possibility.
  • Frequent muscle cramping—The cause could be electrolyte imbalances (e.g., low calcium levels, poorly controlled phosphorous levels) which can result from impaired kidney function.

To these symptoms, the Mayo Clinic [4] adds nausea, vomiting, shortness of breath (caused by fluid buildup in the lungs), and chest pain (caused by fluid buildup around the lining of the heart).

The only way to identify kidney disease is through testing, usually blood and urine testing. Per the Centers for Disease Control and Prevention website [5] (edited for brevity):

A serum creatinine test measures the amount of creatinine in the blood. As kidney function goes down, the serum creatinine level goes up. Normal levels depend on sex, age, and muscle mass. A creatinine level of >1.2 for women and >1.4 for men may be a sign that the kidneys are not working as they should. Other tests may be called for.

Glomerular filtration rate (GFR) is a measure of how well the kidneys remove waste, toxins, and extra fluid from the blood. Serum creatinine level, age, and sex are used to calculate the patient’s GFR number. If the GFR is low, the kidneys are likely to be losing function. As kidney disease progresses, the GFR continues to go down. Healthy kidneys produce a GFR number of >60 together with a normal urine albumin test. A GFR of <60 indicates kidney disease. A GFR of <15 indicates kidney failure.

The Blood Urea Nitrogen (BUN) test measures the amount of urea nitrogen in the blood. Urea nitrogen is a waste product produced by the breakdown of protein. Healthy kidneys filter urea nitrogen, which passes out of the body through urine. A normal level of urea nitrogen depends on the patient’s age and other health conditions but usually ranges from 7 to 20. Higher than normal levels indicate diminished kidney function. As kidney disease progresses, the BUN level goes up.

How Healthmap Solutions (Healthmap) can help

The Healthmap Kidney Population Health Management program is founded on advanced data analytics. Our proprietary algorithms are designed to analyze laboratory results in participating patient populations to provide the earliest possible identification of persons who may be at risk for CKD. We then alert their primary care physicians (PCPs) and provide suggestions for appropriate, evidence-based interventions. Our goal is to expand PCP capabilities without adding to their already considerable workload.

We Are Focused on early CKD awareness. We Are Healthmap!