Heart disease is often thought of as a problem that appears in middle age or later.
But a new study suggests that warning signs connected with heart, kidney and metabolic health may already be common among people in their early 20s.
Researchers found that nearly eight in ten young adults in the study had at least one feature of a condition known as cardiovascular-kidney-metabolic syndrome.
The participants were only about 23 years old on average. Yet those with more advanced health problems were also more likely to show early changes in the arteries of the neck.
These changes can appear long before a heart attack, stroke or other obvious cardiovascular disease develops.
Cardiovascular-kidney-metabolic syndrome, often shortened to CKM syndrome, describes the close relationship between heart disease, kidney disease and metabolic problems such as obesity and diabetes.
These conditions do not develop independently. A problem in one part of the system can increase stress on the others.
For example, excess body fat can make it harder for the body to use insulin normally. High blood sugar and high blood pressure can then damage blood vessels and the kidneys. Kidney problems can, in turn, make blood pressure and cardiovascular disease harder to control.
CKM health is divided into stages. Stage 0 means a person has no identified CKM risk factors, while later stages reflect increasing levels of excess body fat, metabolic problems, kidney disease or cardiovascular damage.
Stage 4 includes people who already have cardiovascular disease such as heart failure, coronary heart disease or stroke.
The new research analyzed 1,283 participants in the Future of Families–Cardiovascular Health Among Young Adults study.
The group was diverse and had an average age of 23. Researchers assessed each participant’s CKM stage and also measured cardiovascular health using the American Heart Association’s Life’s Essential 8 framework.
Life’s Essential 8 looks at eight areas that strongly influence cardiovascular health. These include diet, physical activity, tobacco exposure, sleep, body weight, cholesterol, blood sugar and blood pressure. Rather than waiting for heart disease to appear, the framework focuses on maintaining healthy habits and measurements throughout life.
The researchers found that about 21% of participants were in CKM stage 0. Nearly 80% were already in stages 1, 2 or 3, meaning they had excess body fat, metabolic risk factors or evidence of early cardiovascular changes. None of the participants had reached stage 4.
People with more advanced CKM stages also tended to have poorer Life’s Essential 8 scores. This makes sense because many of the same factors that influence CKM health are included in the eight cardiovascular health measures. However, the researchers found that the two systems could provide complementary information.
The team also used ultrasound to examine the carotid arteries. These large blood vessels run through the neck and supply blood to the brain. Ultrasound allows researchers to measure the thickness and condition of artery walls without surgery or radiation.
Young adults with more advanced CKM syndrome showed more signs of early arterial injury. In particular, their carotid artery walls tended to be thicker. Thickening can be an early sign of atherosclerosis, the process in which fatty material and other substances gradually build up in artery walls.
Atherosclerosis usually develops over many years. Eventually, plaques can narrow arteries or break open and trigger blood clots. Depending on where this happens, the result can be a heart attack or stroke.
The study therefore supports the idea that cardiovascular disease does not suddenly begin at age 50 or 60. The biological processes behind it may start decades earlier. Health conditions in the 20s can help shape cardiovascular risk later in life.
Dr. Donald Lloyd-Jones, an American Heart Association volunteer who was not presented as an investigator in the study, said CKM staging and Life’s Essential 8 may help identify young adults who appear to be moving toward early arterial damage.
He emphasized improving cardiovascular health rather than relying on traditional risk calculators designed for older adults.
Many cardiovascular risk tools estimate a person’s chance of having a heart attack or stroke within the next 10 or 30 years. One newer tool, known as PREVENT, is designed for adults aged 30 to 79. Because the participants in this study were mostly in their early 20s, that calculator was not suitable for them.
This creates a challenge in preventive medicine. A 23-year-old may have a very low chance of suffering a heart attack in the next decade simply because of their age. Yet high blood pressure, unhealthy cholesterol, smoking, poor sleep or high blood sugar at that age may still create damage that matters decades later.
Life’s Essential 8 offers another way to think about risk. Instead of asking only whether a serious event is likely soon, it asks whether a person’s current habits and health measurements are helping protect their cardiovascular system. Improvements made early may have many years to produce benefits.
The study was published in Circulation: Population Health and Outcomes. Its findings support growing calls for cardiovascular prevention to begin earlier, before symptoms or diagnosed heart disease appear. Young adulthood may offer an important opportunity to change the direction of long-term health.
However, the headline finding that nearly 80% had CKM syndrome needs careful interpretation. Stage 1 can include relatively early risk features and does not mean that eight in ten participants had serious heart or kidney disease.
The study population also intentionally included many people from disadvantaged backgrounds, so the percentage may not represent all young adults.
The research was cross-sectional, meaning measurements were taken at a particular point rather than following participants over decades.
It can show that higher CKM stages and arterial changes occurred together, but it cannot prove that the CKM factors caused the artery changes. Long-term follow-up will be needed to determine which young adults eventually develop cardiovascular disease.
Some information about health behaviors was also self-reported, which can introduce errors. People may not perfectly remember or report their diet, physical activity, sleep or other habits. The researchers also examined several outcomes at the same time, which adds complexity to the analysis.
Even with these limitations, the finding of measurable artery differences in people this young is important. It suggests that prevention should not begin only after high blood pressure, diabetes or heart disease has become firmly established.
Young adults can benefit from knowing their blood pressure, cholesterol and blood sugar while also building healthy daily habits.
The most useful message is not that people in their 20s should fear heart disease. It is that cardiovascular health is built over a lifetime, and early adulthood offers a chance to protect it before major damage develops.
Future studies following these participants for many years should show whether early CKM stages truly predict later heart attacks, strokes and kidney disease.
