Hormonal replacement therapy does not affect self-estimated pain or experimental pain responses in post-menopausal women suffering from fibromyalgia: a double-blind, randomized, placebo-controlled trial

Methods. Twenty-nine post-menopausal women were randomized to either 8 weeks of treatment with transdermal 17 beta-oestradiol (50 mu g/day) or placebo according to a double-blind protocol. A self-estimation of pain, a set of quantitative sensory tests measuring thresholds to temperature, thermal pain, cold pain and pressure pain, and a cold pressor test were performed on three occasions: before treatment, after 8 weeks of treatment and 20 weeks after cessation of treatment. Results. Hormonal replacement treatment significantly increased serum oestradiol levels as expected (P < 0.01). However, no differences in self-estimated pain were seen between treatment and placebo groups, nor were there any differences between the two groups regarding the results of the quantitative sensory tests or the cold pressor test at any of the examined time points. Conclusion. Eight weeks of transdermal oestradiol treatment does not influence perceived pain, pain thresholds or pain tolerance as compared with placebo treatment in post-menopausal women suffering from FM.