Why are daytime heart attacks more damaging than nighttime attacks according to the study?

Daytime heart attacks are more damaging because neutrophils, immune cells, are more aggressive during the day, causing increased inflammation and tissue injury.

How can scientists calm down neutrophils to reduce heart attack impact?

Scientists are focusing on receptors like CXCR4 on neutrophils, aiming to develop medicines that can lessen their intensity without compromising overall immunity.

Are there other risks for heart attacks during sleep, besides neutrophil activity?

Yes, risks during sleep include circadian rhythm-induced blood pressure spikes and Obstructive Sleep Apnea (OSA), which strains the heart.

Home / Health / Night vs. Day Heart Attacks: Immune Cells Key?

Night vs. Day Heart Attacks: Immune Cells Key?

19 Dec, 2025

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Summary

Daytime heart attacks cause more tissue damage than nighttime ones.
Aggressive neutrophils during the day are linked to increased damage.
Targeting neutrophil receptors may reduce heart attack severity.

Night vs. Day Heart Attacks: Immune Cells Key?

New research indicates that heart attacks occurring during the day may be significantly more damaging than those happening at night. This difference is attributed to neutrophils, immune cells that exhibit heightened aggression during daylight hours, causing increased inflammation and tissue injury.

A study analyzing over 2,000 heart attack patients revealed higher neutrophil counts and more extensive damage in individuals experiencing attacks during the day. Experiments on mice with depleted neutrophils demonstrated reduced damage, supporting the theory that these cells are central to the severity of heart attacks.

Future efforts aim to develop medicines that can safely moderate neutrophil activity. Targeting receptors like CXCR4 shows promise in calming these cells to nighttime levels, potentially offering a groundbreaking advancement in cardiovascular medicine.