Fast resting heart rate linked to weaker immune function: study

A new study suggests that a fast pulse rate, even at rest, may be associated with lower immunity.

Last Friday, a team of researchers at the Chaum Detox Slimming Center announced the results of their investigation into whether resting heart rate is related to immunity in 7,500 adult men and women.

The researchers studied 7,500 adult men and women and analyzed the relationship between NK cell (immune cell) activity and resting heart rate (pulse), the stress hormone cortisol, and markers of metabolic disease and inflammation (diastolic blood pressure, inflammation levels, and insulin resistance).

Professors Oh Hyo-ju (first author), Lee Yun-kyung (corresponding author), and Seo Eun-kyung of Chaum and Professor Cho Baek-hwan (corresponding author) of the Department of AI Healthcare Convergence at CHA University College of Medicine, Professor Moon Jun-hyung of the Department of Biomedical Informatics at the Graduate School of Medicine of the CHA University College of Medicine, and Professor Cho A-ra of Gangnam Severance Hospital (first author) conducted the study.

Patients were categorized into four groups (≤60 bpm, 60-70 bpm, 70-80 bpm, and ≥80 bpm) according to resting heart rate, and their metabolic and inflammatory markers and natural killer (NK) cell activity were observed.

The results showed that faster resting heart rates were associated with higher metabolic and inflammatory markers, and those with relatively higher resting heart rates (70-80 bpm, ≥80 bpm) tended to have lower NK cell activity than those with lower resting heart rates (≤60 bpm).

This suggests that a faster resting heart rate may be associated with higher inflammatory markers in the body and a higher proportion of immunocompromised patients.

“This large-scale study confirms that resting heart rate can be an important marker of immune function,” Professor Oh said. “By analyzing the effects of cortisol on heart rate, we also confirmed the need to control stress, alcohol, and caffeine intake.”

Professor Lee said, “Even in the absence of high fever or inflammatory response, we found that sudden increases in resting heart rate or blood pressure indicate the need to check and manage immunity.

As many people use smartwatches, monitoring resting heart rate can help manage immunity, Lee added.

The study, “Association between resting heart rate and low natural killer cell activity: A cross-sectional study,” was published in the international journal Frontiers in Immunology.