Nighttime Light Exposure Linked to Heart Damage, Study Finds

7:03 PM ETDeveloping

Health Desk

In Short: A new study published in the European Heart Journal has linked exposure to light during nighttime sleep to potentially harmful changes in the structure and function of the heart, according to researchers at Tulane University.

The study, which involved nearly a million participants, found that those exposed to high amounts of light at night experienced issues with their heart muscle’s ability to flex during heartbeats, an early sign of heart damage. MRI results also showed that participants exposed to high amounts of light had a thickening of the wall of the left ventricle, a key indicator of heart damage.

‘Light pollution has emerged as a new risk factor for cardiovascular disease,’ said senior author Lu Qi, MD, PhD, a researcher with Tulane University. The study highlights the importance of a dark night environment for heart health, with experts recommending that clinicians ask about patients' sleep environments and screen use after sunset.

‘It provides a crucial link between what satellites already show us, i.e. a planet glowing ever brighter at night, and the clinical reality unfolding inside our chests: hearts that are becoming stiffer, weaker, and less efficient,’ wrote Thomas Münzel, MD, and colleagues in an accompanying editorial.

The findings suggest that too much light exposure at night, both when asleep and awake, may be bad for the heart, and could help explain the elevated risk for heart problems associated with too much nighttime light.

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Researchers say the findings, external, from a study of nearly a million people, make this the largest to date to establish the link.
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That was the eye-opening takeaway from a new study published in European Heart Journal.[1] “Previous observational studies have linked nighttime light exposure with a higher risk of cardiovascular disease, but little is known about the related cardiac structure and functional changes,” senior author Lu Qi, MD, PhD, a researcher with Tulane University, said in a statement.
Thomas Münzel, MD, a professor with University Medical Center Mainz in Germany, and two colleagues wrote an editorial in European Heart Journal exploring the implications of this study.[2] “It is time for clinicians, particularly those managing patients with heart failure or atrial fibrillation, to start asking about the sleep environment: how dark the bedroom is, whether the patient works night shifts, and how much screen use occurs after sunset,” the group wrote.
They wore a light sensor on their wrists for seven days.
Exposure to light during nighttime sleep may lead to potentially harmful changes in the structure and function of the heart, according to a study published Wednesday in the European Heart Journal.

Sources

Cardiovascularbusiness link