Roundup: Heart Disease Surpasses Cancer as Top Cause of Death Among U.S. Hispanics; and More News

Heart Disease Now Leading Cause of Death Among Hispanic Adults in U.S.: New Report

Cardiovascular disease has surpassed cancer as the leading cause of death among Hispanic adults in the United States, according to a new scientific statement from the American Heart Association (AHA).

The shift comes amid high rates of obesity, type 2 diabetes, high blood pressure and other cardiovascular risk factors that often emerge at younger ages among Hispanic adults. The AHA statement, published in Circulation, also emphasizes that social, economic and environmental factors can influence a person’s risk of developing heart disease.

Heart Risks Can Appear Earlier

Nearly 46 percent of Hispanic adults have obesity, while 15.5 percent have type 2 diabetes — nearly twice the prevalence among white adults. About 44 percent have high blood pressure, but awareness, treatment and control of the condition remain lower than among white adults.

These risk factors can translate into cardiovascular disease earlier in life. Hispanic adults are diagnosed with heart failure about eight to nine years earlier than white adults, according to the statement. Heart failure occurs when the heart cannot pump enough blood to meet the body's needs.

Hispanic adults also experience a first stroke an average of six to eight years earlier — at about age 67 compared with ages 73 to 75 among white adults.

Lifestyle Factors Also Play a Role

The AHA evaluated cardiovascular health using measures that include diet, physical activity, sleep, blood pressure, blood sugar, cholesterol, body weight and tobacco exposure.

The statement found that fewer than 2 percent of Hispanic adults meet recommended sodium intake goals and fewer than 10 percent meet recommendations for healthy fats. About one-third report sleeping fewer than seven hours per night, which has been linked to obesity, diabetes and high blood pressure.

Nearly one-third report getting no moderate-to-vigorous physical activity during their leisure time.

Heart Health Is About More Than Biology

The statement emphasizes that cardiovascular disparities cannot be explained by medical risk factors alone.

Limited health insurance, language barriers, food insecurity, environmental exposures and access to healthcare can affect people's ability to prevent disease or manage chronic conditions. About 20 percent of Hispanic adults were uninsured in 2023, according to the report.

The authors also stress that Hispanic communities are highly diverse. Cardiovascular risks and health outcomes can vary among people of Mexican, Puerto Rican, Cuban, Dominican, Central American and South American heritage, as well as between U.S.-born and foreign-born individuals.

Improving Prevention and Access to Care

The AHA calls for culturally relevant cardiovascular education, better access to bilingual healthcare resources, stronger community partnerships and greater Hispanic representation in medical research.

The statement also highlights the importance of addressing risk factors early. Maintaining a healthy blood pressure, blood sugar and cholesterol level, eating a nutritious diet, staying physically active and getting adequate sleep can all contribute to better cardiovascular health.

At the community level, the authors say improving access to healthcare, healthy foods, safe places for physical activity and accurate health information will be essential to reducing cardiovascular disease as the U.S. Hispanic population continues to grow and age.

Alzheimer’s Changes in the Brain May Begin Years Before Plaques are Detected, Study Finds

New research suggests that the earliest changes linked to Alzheimer’s disease may begin much sooner than previously believed. Researchers at the University of Oslo found that structural changes in the brain can be detected at least seven years before the buildup of amyloid plaques — a hallmark of Alzheimer’s disease — becomes visible on the specialized brain scans currently used to identify the disease.

The findings, published in Nature Neuroscience, could eventually improve the early detection of Alzheimer’s and help researchers develop treatments that target the disease before memory problems begin.

Looking for Signs Before Symptoms Appear

Today, one of the primary ways researchers detect the earliest stages of Alzheimer’s is with an amyloid positron emission tomography (PET) scan. This imaging test looks for amyloid plaques, abnormal protein deposits that accumulate in the brains of people with Alzheimer’s disease.

However, the new study suggests important brain changes may occur long before those plaques can be detected.

Researchers followed healthy older adults for nearly 20 years, using magnetic resonance imaging (MRI) scans to monitor changes in brain structure. MRI uses magnets and radio waves to create detailed images of the brain and does not involve radiation.

By identifying when participants first developed detectable amyloid plaques, the researchers were able to review MRI scans from the previous decade. They found that people who later developed plaques had measurable thinning in parts of the brain at least seven years before plaque buildup became visible on PET scans.

Importantly, the participants remained cognitively healthy during this early period, meaning they had no noticeable problems with memory or thinking.

Why Earlier Detection Matters

Although the findings are promising, they do not mean MRI scans are ready to diagnose Alzheimer’s years before symptoms appear.

Instead, the research offers scientists a better understanding of how the disease develops and may help identify people at higher risk much earlier in the disease process.

Earlier detection could also improve clinical trials by allowing researchers to test new treatments before significant brain damage occurs.

What It Could Mean for Future Treatments

Most experimental Alzheimer’s therapies have focused on reducing amyloid plaques. But the new findings raise the possibility that other harmful changes in the brain may begin even earlier.

If that proves true, future treatments may need to target biological processes that occur before amyloid plaques become detectable.

Researchers emphasize that additional studies are needed to confirm the findings and determine whether these early structural changes can eventually become part of routine screening or treatment strategies.

What This Means for Patients Today

The study does not change current recommendations for diagnosing Alzheimer’s disease. There is still no routine screening test for people without symptoms, and MRI scans cannot currently diagnose the disease before cognitive problems develop.

However, the research provides encouraging evidence that scientists are gaining a clearer picture of Alzheimer’s long before memory loss begins. That growing understanding may ultimately lead to earlier diagnosis, more effective treatments and, one day, better ways to prevent or delay the disease altogether.

Sleeping With Exposure to Certain Levels of Light Could Raise Risk of Heart Disease, Research Finds

Exposure to light while sleeping — even at low levels — may be associated with subtle changes in the heart and a higher risk of cardiovascular disease, according to a large study published in the European Heart Journal.

Researchers found that people exposed to higher levels of nighttime light showed differences in the heart’s structure and function, compared with those who had little or no nighttime light exposure. The findings add to evidence that maintaining a dark sleep environment and getting adequate sleep may be important for cardiovascular health.

Tracking Light Exposure and the Heart

The study included more than 11,000 participants from the UK (United Kingdom) Biobank who wore wrist devices equipped with light sensors for seven days. About three years later, researchers evaluated their hearts using cardiovascular magnetic resonance, or cardiac MRI, a detailed imaging test that measures the heart’s size, structure and pumping function.

Researchers focused on nighttime exposure above 3 lux, a relatively low level of illumination. That threshold was selected because light at that level may interfere with the release of melatonin, a hormone that helps regulate the body's sleep-wake cycle. Lux is a basic measurement of light. At 3 lux, the human eye can see shapes and outlines, but reading text or discerning fine details becomes difficult without straining.

After accounting for factors such as age, smoking, physical activity, body mass index, high blood pressure and diabetes, greater nighttime light exposure was associated with changes involving several chambers of the heart.

Participants with high nighttime light exposure had 2.4 percent greater left ventricular mass and thicker walls in the left ventricle, the heart's main pumping chamber. They also showed signs of slightly poorer heart-muscle performance. Researchers found similar unfavorable changes involving the right ventricle and left atrium.

These changes were small and do not mean that sleeping with a light on will cause heart disease. The study was observational, meaning it identified associations rather than proving that nighttime light directly caused the changes.

Higher Cardiovascular Risks Over Time

Researchers also examined cardiovascular outcomes among more than 70,000 participants over eight to 10 years.

Compared with people who had no nighttime exposure above 3 lux, those with high exposure had a 29 percent higher risk of heart failure, 15 percent higher risk of atrial fibrillation — an irregular heart rhythm — and 24 percent higher risk of heart attack. Stroke risk was 33 percent higher, while the risk of dying from cardiovascular disease was 26 percent higher.

Sleep May Help Explain the Connection

One possible explanation involves the body's circadian rhythm, its internal 24-hour clock. Light is a major signal controlling this system, which influences blood pressure, heart rate and other cardiovascular functions. Artificial light at night may disrupt these natural rhythms.

Sleep duration also appeared important. Researchers estimated that shorter sleep explained about 24 percent to 49 percent of several associations between nighttime light and unfavorable heart changes.

The findings do not establish that eliminating all nighttime light prevents cardiovascular disease. But they suggest that limiting unnecessary light in the bedroom and protecting adequate sleep may be simple habits worth considering as part of an overall heart-healthy lifestyle.