Olfactometric and rhinomanometric outcomes in post-menopausal women treated with hormone therapy: a prospective study

Background: The aim of this prospective study was to evaluate the effects of hormone therapy (HT) on olfactory sensitivity in post-menopausal women. Methods: Forty-six naturally post-menopausal women underwent rhinomanometric and olfactometric measurements to compare nasal airflow resistance values and olfactometric thresholds during the eighth month of HT treatment with baseline levels prior to starting HT. Eighteen women used an oral HT regimen, and twenty-eight women used transdermal patch HT. Results: Rhinomanometric values during HT were statistically differ from those at baseline (P<0.001). Olfactometric threshold data indicated a higher sensitivity during the HT treatment than at baseline (P<0.001). Finally, no statistically significant difference was observed among women using oral or patch HT administration on rhinomanometric and olfactometric values. Conclusions: Our study demonstrates that 8 months of treatment with estrogen and progestogens in HT preparations has an effect on nasal airflow resistance and the olfactory thresholds to odours. We believe that estrogens could influence neuronal plasticity, and the neuronal conduction time into the olfactory system. Our findings confirm that gonadal steroids such as estrogen have an influence on non-genital targets; this relationship might have a beneficial impact on sensorineural communication and emotional behaviour.