ABSTRACT
BACKGROUND: Neurotransmitter norepinephrine seems to be involved in the pathophysiology of hot flushes in postmenopausal women, and folic acid was found to interact with its receptors. OBJECTIVES: To examine the effect of folic acid supplementation on the occurrence of hot flushes and the plasma level of 3-methoxy 4-hydroxy phenyl glycol (MHPG, the main metabolite of brain norepinephrine). METHOD: Forty-six postmenopausal women were allocated (by alternation) into 2 groups (n = 23 each); Group 1 received folic acid 5mg tablets daily for 4 weeks and group 2 received placebo tablets. Four women in group 2 discontinued the study. RESULTS: The number of women who reported improvement in hot flushes was significantly higher in the treatment group. On comparing the mean plasma levels of MHPG before and after treatment, a significant lowering was found in the treatment group (mean % change = -24.1 +/- 17.9, p < 0.001) when compared with the placebo-control group (mean % change = -5.59 +/- 16.4, p = 0.10). In the treatment group, there was a significant negative correlation between improvement in hot flushes and the plasma level of MHPG (r = -0.453, p = 0.03). CONCLUSION: Folic acid supplementation may cause subjective improvement of hot flushes by lowering the increased central noradrenergic activity.
