Table 1.

Correlation between heart rate variability measures and inflammatory markers and diseases

Year	Authors	Subjects	Main findings
2007	Coruzzi P, et al. [29]	26 ulcerative colitis patients and 26 Crohn’s disease patients	pNN50 and RMSSD were significantly lower in the ulcerative colitis group than both the Crohn’s disease group and the control group. However, Crohn’s disease patients showed comparable HRV to the controls
2011	Kox M, et al. [30]	40 healthy volunteers receiving intravenous endotoxin	Acute inflammatory responses result in HRV changes (log SDNN, log LF/HF, LFnu, and HFnu), but the extent of the inflammatory response did not correlate with the HRV change magnitude
2012	Vlcek M, et al. [31]	22 female RA patients < 40 years	Plasma epinephrine and norepinephrine were similar in RA patients and controls. No differences in HRV and blood pressure response to orthostasis were found
2012	Thayer JF, et al. [32]	611 apparently healthy employees of a factory (545 male, 18–63 years)	Urinary norepinephrine was positively associated with WBC. An inverse association between indices of vagally mediated HRV (RMSSD and pNN50) and plasma levels of CRP was found
2014	Jarczok MN, et al. [33]	106 nonsmoking adults (9% women; age 44 ± 8 years)	Higher HF-HRV was associated with lower levels of CRP at both baseline and 4-year follow-up
2017	Adlan AM, et al. [34]	RA-normotensive (n = 13), RA-HTN (n = 17), normotensive control (n = 17), HTN control (n = 16)	The RA, RA-HTN, and HTN groups have lower HRV time and frequency domain measures (rMSSD, pNN50, HF power, LF power, and total power) than the control group. Hs-CRP and reported pain were independently and inversely associated with time-domain rMMSD and pNN50
2017	Aeschbacher S, et al. [35]	2064 healthy adults (47% men, 25–41 years)	Significant inverse and linear associations of SDNN with hs-CRP, leukocytes, neutrophils, lymphocytes, and monocytes were found. Total power and normalized HF power were inversely associated with some of the markers
2018	Zawadka-Kunikowska M, et al. [36]	Crohn’s disease patients in remission (n = 30)	Disease duration was negatively associated with baroreflex sensitivity and positively correlated with normalized high-frequency HRV, LF/HF ratio at rest, and post-tilt Δ systolic blood pressure
2018	Hu MX, et al. [37]	1774 subjects from the Netherlands Study of Depression and Anxiety	Higher CRP and IL-6 levels predicted lower respiratory sinus arrhythmia at follow-up
2021	Alen NV, et al. [38]	836 community participants (450 female, 53 ± 13 years)	Robust inverse relations were found between HF power and IL-6, CRP, and fibrinogen. LF power was also inversely related to IL-6 and CRP

CRP C-reactive protein, HF high frequency, HRV heart rate variability, hs-CRP high-sensitivity C-reactive protein, HTN hypertension, IL-6 interlukin-6, LF low frequency, pNN50 percentage of successive RR intervals that differ by more than 50 ms, RA rheumatic arthritis, RMSSD root mean square of successive RR interval differences, SDNN standard deviation of NN intervals, WBC white blood cell