Metabolic syndrome and short-term and long-term heart rate variability in elderly free of clinical cardiovascular disease: the PROOF study.
OBJECTIVE
Autonomic nervous system (ANS) activity decrease has been associated with a higher risk of sudden cardiovascular and cerebrovascular disease. Thus, we explored the relationship between ANS control of the cardiovascular system and metabolic syndrome.


METHODS
We analyzed the relationship with both short-term and long-term heart rate variability (HRV) and metabolic syndrome in the cross-sectional PROgnostic indicator OF cardiovascular and cerebrovascular events (PROOF) cohort study of 1,011 elderly subjects recruited amongst the inhabitants of the city of Saint Etienne, France, aged 65.6 ± 0.8 years at the inclusion date. Physical examination included measurements of height, weight, systolic and diastolic blood pressure, waist circumference, and biological parameters. HRV variables were measured over 5-min, nighttime, and 24-h periods using Holter monitoring.


RESULTS
After adjustment for current type 2 diabetes, depression, and smoking, we found that metabolic syndrome status, high-density lipoprotein cholesterol (HDL-C), and waist circumference were significantly (p < 0.05) associated with total power, very-low frequency, low-frequency/high-frequency (LF/HF) ratio, and normalized LF. HDL-C and metabolic syndrome status were significantly associated with decreased long-term HRV variables. Both nighttime and 24-h HRV showed closer associations with metabolic syndrome than did short-term HRV (5-min). Metabolic syndrome severity was associated with a decrease in both the long-term and short-term HRV variables.


CONCLUSIONS
ANS control alteration of the cardiovascular system was more pronounced when evaluated by long-term than short-term HRV recordings, particularly in women.
Assoumou
H G Ntougou
HG
SNA-EPIS Research Unit, Exercise and Clinical Physiology Laboratory, University Hospital and Jean Monnet University, Pres Lyon, Saint-Etienne, France. gabingabon@hotmail.com
Pichot
V
V
Barthelemy
J C
JC
Dauphinot
V
V
Celle
S
S
Gosse
P
P
Kossovsky
M
M
Gaspoz
J M
JM
Roche
F
F
D000368:Aged; D002318:Cardiovascular Diseases / Q000150:complications* / Q000503:physiopathology*; D015331:Cohort Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000503:physiopathology*; D013997:Time Factors