Effect of tibolone administration on heart rate variability and free fatty acid levels in postmenopausal women.
OBJECTIVE
To evaluate the effects of tibolone on heart rate variability and plasma free fatty acid levels in postmenopausal women.


METHODS
Randomized, placebo-controlled trial.


METHODS
University hospital.


METHODS
Thirty postmenopausal women.


METHODS
Tibolone, 2.5 mg/d, or placebo for 4 months.


METHODS
Variability in heart rate and changes in the lipid profile.


RESULTS
Anthropometric data were unchanged throughout the study. Compared with placebo, long-term tibolone administration was associated with a decrease in plasma levels of low-density lipoprotein cholesterol, triglyceride, and free fatty acid and homeostasis model assessment index. Furthermore, tibolone administration was associated with an increase in RR interval, total power, and high frequency and decrease in low frequency and the low frequency/high frequency ratio. Finally, the delta decrease in plasma free fatty acid levels correlated with delta low frequency/high frequency ratio independently of age, delta body mass index, delta homeostasis model assessment index, and low-density lipoprotein cholesterol levels.


CONCLUSIONS
Long-term tibolone administration improves the ratio of cardiac sympathetic tone to parasympathetic tone in postmenopausal women.
Manzella
Daniela
D
Department of Geriatric Medicine and Metabolic Diseases, Second University of Naples, Naples, Italy.
Fornaro
Felice
F
Carbonella
Marco
M
Picardi
Ciro
C
Paolisso
Giuseppe
G
Colacurci
Nicola
N
D008078:Cholesterol, LDL / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008875:Middle Aged; D009652:Norpregnenes / Q000627:therapeutic use*; D017698:Postmenopause / Q000502:physiology*
D008078:Cholesterol, LDL; D005230:Fatty Acids, Nonesterified; D009652:Norpregnenes; C027385:tibolone