Millions of adults may be carrying a serious cardiovascular risk without realizing it because the problem does not always begin in the heart. Researchers and public health experts are warning that undiagnosed kidney disease, diabetes and metabolic problems can quietly increase the likelihood of heart attack, stroke and heart failure long before obvious cardiac symptoms appear.
The concern centers on the close relationship between cardiovascular health, kidney function and the way the body manages blood sugar, cholesterol and energy. The American Heart Association describes this connection as cardiovascular-kidney-metabolic syndrome, commonly shortened to CKM syndrome.
According to the association’s 2026 report on hidden heart risks, nearly one in four U.S. adults with diabetes does not know they has the condition. As many as nine in ten adults with chronic kidney disease may also be unaware that their kidneys are damaged.
Heart Disease Can Develop Outside the Heart
Heart disease is often associated with blocked arteries, high cholesterol or an unhealthy heart muscle. However, cardiovascular damage can develop through a much wider network of biological problems.
The kidneys regulate fluid levels, remove waste from the blood and help control blood pressure. When kidney function declines, the body may retain excess fluid and sodium, placing greater pressure on blood vessels and the heart. Damaged kidneys can also disrupt hormones involved in blood-pressure regulation and red blood cell production.
Diabetes creates a different but closely connected threat. Persistently high blood sugar can damage blood vessels and nerves throughout the body. Over time, this damage may affect the coronary arteries, kidneys and circulation, increasing the risk of heart disease and stroke.
These conditions also share many of the same risk factors, including high blood pressure, abnormal cholesterol, excess abdominal fat, reduced kidney function and poor blood-sugar control. As a result, developing one condition can increase the likelihood of developing the others.
Millions May Be Living With Undiagnosed Disease
The scale of the problem is significant because both kidney disease and diabetes can progress quietly.
Early chronic kidney disease often causes few noticeable symptoms. A person may feel generally well even while the kidneys are gradually losing their ability to filter the blood. Symptoms such as swelling, fatigue, nausea or changes in urination may not appear until the disease has become more advanced.
Type 2 diabetes and prediabetes can also remain undetected for years. Blood sugar may rise gradually, allowing blood-vessel damage to develop before a person receives a diagnosis.
The American Heart Association reports that about half of U.S. adults have high blood pressure, roughly one in three has high total cholesterol and more than half has prediabetes or diabetes. More than half also have a high waist circumference, while approximately one in seven has kidney disease.
These overlapping conditions mean that a person who appears to have only a blood-pressure or weight problem may already have several connected cardiovascular risks.
CKM Syndrome Explains the Hidden Connection
CKM syndrome is a framework used to describe how heart disease, kidney disease, obesity and diabetes influence one another.
The cardiovascular element includes conditions such as heart attack, stroke, heart failure and disease of the blood vessels. The kidney element covers reduced filtration, protein leakage into the urine and chronic kidney damage. The metabolic element includes obesity, insulin resistance, prediabetes and diabetes.
These conditions do not always appear in a fixed order. Kidney disease may increase cardiovascular risk, diabetes may damage both the kidneys and heart, or obesity may contribute to high blood pressure and insulin resistance before either organ shows obvious symptoms.
The American Heart Association’s CKM health information explains that treating these risks as a connected system may help doctors identify problems earlier instead of addressing each diagnosis separately.
The greatest long-term threats from CKM syndrome are disability and death caused by heart disease and stroke. That is why a kidney or blood-sugar abnormality should not be viewed as unrelated to cardiovascular health.
Kidney Screening Is Frequently Missed
One of the biggest gaps involves screening people who already have diabetes or high blood pressure.
The American Heart Association says two-thirds of patients with either condition may not know they also have kidney disease, partly because they have not received a urine albumin-to-creatinine ratio test, known as a uACR test.
The uACR test measures albumin, a protein that may leak into the urine when the kidneys’ filtering units are damaged. Even a small amount can be an early warning sign.
A second test, called estimated glomerular filtration rate or eGFR, uses a blood measurement to estimate how effectively the kidneys are filtering waste. The tests examine different aspects of kidney health, which is why healthcare professionals may use both.
The National Kidney Foundation’s kidney testing guidance explains how blood and urine tests can detect kidney problems before severe symptoms develop.
A normal-looking blood pressure reading or lack of pain does not prove that the kidneys are healthy. Kidney disease is often silent, making laboratory screening particularly important for people with diabetes, hypertension, cardiovascular disease or a family history of kidney problems.
Routine Tests Can Reveal the Risk Earlier
Screening for CKM-related risk does not necessarily require complex imaging or an invasive procedure. Much of the initial assessment can be completed through routine measurements and laboratory tests.
Blood pressure can reveal hypertension that is placing strain on the heart, kidneys and blood vessels. A cholesterol panel measures total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides.
Blood sugar can be assessed through fasting glucose or an A1C test, which reflects average glucose levels over the previous two to three months. Weight, body mass index and waist circumference can provide additional information about metabolic risk.
Kidney health can then be assessed through eGFR and uACR testing. A healthcare professional can combine these results with age, smoking history and other factors to estimate a person’s future cardiovascular risk.
The CDC’s chronic kidney disease information notes that people with diabetes and high blood pressure face a higher risk of kidney disease, reinforcing the need to screen beyond traditional heart measurements.
A Normal Heart Test May Not Tell the Whole Story
Someone may have no chest pain, a normal resting heart rhythm and no history of heart attack while still carrying significant cardiovascular risk.
Early damage may be developing through high blood sugar, declining kidney function or long-term hypertension. These problems can slowly alter blood vessels, promote inflammation and increase the workload placed on the heart.
This is why heart prevention should not begin only when symptoms appear. By the time shortness of breath, chest discomfort or swelling develops, an underlying condition may already be advanced.
The American Heart Association estimates that approximately 80% of heart attacks and strokes are preventable through earlier detection, lifestyle changes and appropriate treatment. Risk factors often develop gradually and may produce few or no symptoms at first.
One Treatment Plan May Protect Several Organs
The interconnected nature of CKM syndrome also creates an opportunity. Improving one part of the system may benefit several organs simultaneously.
Controlling blood pressure can reduce stress on the heart and slow kidney damage. Better blood-sugar management may protect blood vessels, nerves and kidney filters. Losing excess weight and increasing physical activity can improve insulin sensitivity, cholesterol and cardiovascular fitness.
Avoiding smoking, getting adequate sleep and choosing a diet lower in excess sodium, refined carbohydrates and heavily processed foods may also support heart, kidney and metabolic health.
Medication may be necessary when lifestyle changes alone are insufficient. Some modern treatments for diabetes, kidney disease and heart failure have shown benefits across more than one organ system, but the appropriate choice depends on the individual’s diagnosis, kidney function and overall medical history.
Patients should not start or stop medication based on general health reports. Treatment decisions should be made with a qualified healthcare professional who can review laboratory results, symptoms and possible interactions.
Hidden Risk Does Not Mean Inevitable Disease
The warning is serious, but it should not be interpreted as evidence that everyone with diabetes or kidney disease will experience a heart attack.
Risk depends on the severity of the condition, how early it is detected and how effectively it is managed. A person diagnosed through routine screening may have an opportunity to make changes years before a major cardiovascular event occurs.
The most important lesson is that heart health cannot always be evaluated by looking at the heart alone. Blood pressure, blood sugar, waist circumference, cholesterol and kidney function are parts of the same risk picture.
Millions may be unaware of the danger because the earliest warning appears in a urine test, a glucose result or a gradual decline in kidney filtration rather than chest pain. Recognizing that connection could help patients and clinicians detect cardiovascular risk earlier and protect the heart before the damage becomes harder to reverse.
