Auditory brainstem response in postmenopausal women treated with hormone replacement therapy: a pilot study

The impact of menopausal status on auditory brainstem responses

OBJECTIVE

To determine the effect of decreased estrogen levels due to menopause on auditory brainstem response measurements (ABR).

STUDY DESIGN

Retrospective chart review.

SETTING

Academic.

PATIENTS

Pre- and post-menopausal females (pre-M, post-M) and age-matched males.

METHODS

ABR measurements of wave I, III, and V latencies, and interpeak latencies; amplitudes of waves I, III, V, and V/I ratio.

OUTCOME MEASURE

Differences in ABR measurements between pre-M and post-M.

RESULTS

164 subjects (101 female and 64 male) were included. Post-M had significantly greater latencies (msec) than pre-M of wave V. Post-M had a significantly smaller wave I amplitude (uV) than pre-M. Post-M had a significantly higher wave V/I amplitude ratio than pre-M. Pre-M had significantly shorter latencies than young males for wave III, and wave V. Post-M had significantly shorter latencies than older males at wave III, and wave V. A two-way ANOVA revealed a significant interaction between the effects of age category and gender on V/I amplitude.

CONCLUSION

Post-M group showed a significant drop in wave I amplitude compared with pre-M group, even in the absence of hearing loss, suggesting that the gender differences in hearing are related to estrogen signaling along the auditory pathway. If wave I amplitude changes between older and younger groups resulted from decreased peripheral hearing sensitivity, we would expect larger drops in amplitude in males since rates of presbycusis are higher. We observed much larger drops in wave I amplitude in females, which cannot be attributed to peripheral hearing loss. These results may assist in understanding gender differences in presbycusis and a possible protective effect of estrogen on the auditory system. Knowledge of gender differences in wave I may be important when ABR is used to assess possible synaptopathy.

Sex differences and the effect of female sex hormones on auditory function: a systematic review

Aims

First, to discuss sex differences in auditory function between women and men, and whether cyclic fluctuations in levels of female sex hormones (i.e., estradiol and progesterone) affect auditory function in pre-menopausal and post-menopausal women. Second, to systematically review the literature concerning the discussed patterns in order to give an overview of the methodologies used in research. Last, to identify the gap in knowledge and to make recommendations for future work.

Methods for the systematic review

Population, Exposure, Control, Outcome and Study design (PECOS) criteria were used in developing the review questions. The review protocol follows the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was pre-registered in the Prospective Register of Systematic Reviews (PROSPERO; CRD42020201480). Data Sources: EMBASE, PubMed, MEDLINE (Ovid), PsycINFO, ComDisDome, CINAHL, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL) via Cochrane Library, and scanning reference lists of relevant studies, and internet resources (i.e., Mendeley) were used. Only studies published between 1999 and 2022, in English, or in English translation, were included. The quality of evidence was assessed using the Newcastle-Ottawa Scale (NOS).

Results

Sex differences: Women had more sensitive hearing (measured at the level of peripheral and central auditory system) than men. Cyclic fluctuations: Auditory function in women fluctuated during the menstrual cycle, while no such fluctuations in men over the same time period were reported. Hearing sensitivity improved in women during the late follicular phase, and decrease during the luteal phase, implying an effect of female sex hormones, although the specific effects of estradiol and progesterone fluctuations on the central auditory system remain unclear. Hearing sensitivity in women declined rapidly at the onset of menopause.

Conclusion

The review has shown the following. Consistent sex differences exist in auditory function across the auditory pathway with pre-menopausal women often showing better function than age-matched men. Moreover, pre-menopausal women show fluctuations in hearing function across the menstrual cycle with a better function during the peak of estradiol or when the ratio of estradiol to progesterone is high. Third, menopause marks the onset of hearing loss in women, characterized by a rapid decline in hearing sensitivity and a more pronounced loss than in age-matched men. Finally, the systematic review highlights the need for well-designed and -controlled studies to evaluate the influence of estradiol and progesterone on hearing by consistently including control groups (e.g., age-matched man), using objective tests to measure hormonal levels (e.g., in saliva or blood), and by testing participants at different points across the menstrual cycle.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020201480, identifier CRD42020201480.

Effects of hormone therapy containing 2 mg drospirenone and 1 mg 17β-estradiol on postmenopausal exacerbation of Meniere's disease: Preliminary study

The present study aimed to evaluate the effects of 2 mg drospirenone (DRSP) and 1 mg 17β-estradiol (E2) hormone therapy (HT) in combination with rehabilitation therapy for postmenopausal women with Meniere's disease (MD). The combined drug hormone treatment was denoted as DRSP/E2. A total of 65 postmenopausal female patients with MD and severe distress were enrolled in the present prospective study. A total of 31 women comprised the study group (group A), undergoing HT and rehabilitation therapy, whereas 34 women who opted for rehabilitation therapy alone comprised the control group (group B). Vestibular function and distress associated with MD were assessed by stabilometry and the Dizziness Handicap Inventory (DHI) questionnaire, respectively. The data were collected at baseline and during the 3- and 6-month follow-up visits. The areas of the stabilometric ellipses exhibited a higher reduction in group A compared with group B with regard to the baseline values at both follow-up assessments (P<0.001). At baseline, both groups exhibited severe self-perceived discomfort, with similar DHI scores of 72.3±3.7 (group A) and 70.6±3.9 (group B; P=0.07). At the 3-month follow-up, both groups underwent a gradual improvement, which was significantly higher in group A (47.5±3.7) compared with in group B (64.2±3.3; P<0.001). At the 6-month follow-up, the DHI scores were improved in group A (43.4±3.4) compared with in group B (58.5±3.1; P<0.001). Therefore, DRSP/E2 HT was effective in reducing the fluid overload, which is characteristic of MD. The findings of the present study demonstrated that integrated therapy based on the administration of DRSP/E2 HT and rehabilitation may be more effective compared with rehabilitation alone for the management of postmenopausal exacerbation of MD.

Effects of endogenous and exogenous oestrogen exposure on hearing level in postmenopausal women: A cross-sectional study

OBJECTIVE

To investigate the effect of endogenous and exogenous oestrogen exposure on hearing levels in postmenopausal women.

STUDY DESIGN

Retrospective cross-sectional study.

SETTING

Population-based survey data collected by the Korean National Health and Nutrition Survey between 1 January 2010 and 31 December 2012.

SUBJECTS AND METHODS

Participants comprised 3653 postmenopausal women. Detailed histories for reproductive factors and data on the use of hormone replacement therapy were obtained through health questionnaires and otologic examinations, including pure-tone audiogram and otoscopic findings. Complex-sample linear regression models controlling for confounding factors were generated to determine whether hormone-related factors were associated with hearing loss.

RESULTS

Women who experienced a longer duration of oestrogen exposure had better hearing compared to those who do not in multivariate model adjusting for confounding factors with a lower adjusted beta coefficient of hearing threshold (β = -0.18, 95% confidence interval = -0.3 to -0.07, P = .002). The results also suggested that hormone replacement therapy may be beneficial for attenuating hearing loss (β = -1.22, 95% confidence interval = -2.19 to -0.25, P = .014), particularly in the high-frequency range from 3 to 6 KHz.

CONCLUSION

A longer duration of lifetime oestrogen exposure (LEE) and the use of hormone replacement therapy are likely to attenuate hearing loss. These epidemiologic data provide evidence that oestrogen may be beneficial for attenuating age-related hearing decline.

Estrogen Replacement Reduces Hearing Threshold Shifts and Cochlear Hair Cell Loss After Acoustic Overexposure in Ovariectomized Rats

Objectives.

The relationship of estrogen (the primary female sex hormone) with hearing function has been studied in both humans and animals. However, whether estrogen levels affect hearing remains uncertain. Therefore, in this study, we investigated changes in the vulnerability of hearing to acoustic overexposure in ovariectomized female rats.

Methods.

Eighteen 8-week-old female Sprague-Dawley rats were separated into four groups as follows: sham ovariectomy (OP), OP only, and OP treated with low (10 µg/kg) or high doses (100 µg/kg) of estrogen. Rats in the estrogen replacement groups were given two intraperitoneal injections. Hearing thresholds were measured before noise exposure, and at 1 day and 2 weeks after exposure.

Results.

The hearing thresholds of the sham OP and OP-only groups were not significantly different. However, both estrogen groups showed a lower threshold shift than the OP-only group. Histological immunostaining analyses showed that hair cell loss in the 32 kHz region was more severe in the sham OP group than in the OP-only group. Furthermore, there was little or no hair cell loss in either estrogen replacement group and significantly more hair cell loss in the OP-only group.

Conclusion.

These results suggest that estrogen replacement may reduce the vulnerability of hearing to noise exposure in menopausal women.

Hearing Performance in the Follicular-Luteal Phase of the Menstrual Cycle

Introduction

Estrogen has a protective role on auditory function. It may have an excitatory action on auditory nerve fibers and can have a neuroprotective effect. Progesterone has a mainly inhibitory action on the central nervous system, which may balance the mainly excitatory action of estrogen.

Objective

To determine changes in hearing performance with pure tone audiometry (PTA), tympanometry, distortion product otoacoustic emissions (DPOAEs), and auditory brainstem responses (ABR) as hormonal changes occur from follicular to luteal phase.

Materials and Methods

Twenty healthy female volunteers (age 19 ± 30 years) with normal menstrual cycle and without any hearing problems are included in this case-control study. Hearing evaluation was performed on the 13th day of the menstrual cycle (follicular phase) and then on the 22nd day (luteal phase).

Results

All of the participants had normal results in follicular phase. In luteal phase, four cases showed abnormalities as follows: reduced hearing thresholds 250 Hz (mean= 15 dBHL), increased amplitudes of DPOAE (mean= 3 dBspl), decreased middle ear pressure (mean= -110 dapa), and delayed ABR interpeak latencies (mean of IPLs I-III= 0.4 and mean of IPLs III-V= 0.6 ms).

Conclusions

In some women, changing of ovarian hormones may induce fluctuating hearing and increased progesterone in luteal phase can lead to abnormal outcomes in auditory function. However, elevated estrogen modifies its consequences in follicular phase.

Menopause and postmenopausal hormone therapy and risk of hearing loss

OBJECTIVE

Menopause may be a risk factor for hearing loss, and postmenopausal hormone therapy (HT) has been proposed to slow hearing decline; however, there are no large prospective studies. We prospectively examined the independent relations between menopause and postmenopausal HT and risk of self-reported hearing loss.

METHODS

Prospective cohort study among 80,972 women in the Nurses' Health Study II, baseline age 27 to 44 years, followed from 1991 to 2013. Baseline and updated information was obtained from detailed validated biennial questionnaires. Cox proportional-hazards regression models were used to examine independent associations between menopausal status and postmenopausal HT and risk of hearing loss.

RESULTS

After 1,410,928 person-years of follow-up, 18,558 cases of hearing loss were reported. There was no significant overall association between menopausal status, natural or surgical, and risk of hearing loss. Older age at natural menopause was associated with higher risk. The multivariable-adjusted relative risk of hearing loss among women who underwent natural menopause at age 50+ years compared with those aged less than 50 years was 1.10 (95% confidence interval [CI] 1.03, 1.17). Among postmenopausal women, oral HT (estrogen therapy or estrogen plus progestogen therapy) was associated with higher risk of hearing loss, and longer duration of use was associated with higher risk (P trend < 0.001). Compared with women who never used HT, the multivariable-adjusted relative risk of hearing loss among women who used oral HT for 5 to 9.9 years was 1.15 (95% CI 1.06, 1.24) and for 10+ years was 1.21 (95% CI 1.07, 1.37).

CONCLUSIONS

Older age at menopause and longer duration of postmenopausal HT are associated with higher risk of hearing loss.

Investigation of auditory potentials and cognitive impairment in premenstrual syndrome

Premenstrual syndrome is a term which is used for describing of somatic, cognitive, emotional, and behavioral symptoms that occur during the luteal phase of menstrual cycle in women of reproductive age; symptoms rapidly improve at the onset of menstruation. In this study, we aimed to reveal if cognitive functions are affected or not in PMS and if the subjects are affected, we try to explain this situation by an objective diagnostic test. Ethical committee approval was taken for this project on 09.03.2012 and numbered 050.99-60. In this study, in order to determine premenstrual syndrome, "Premenstrual Syndrome Scale" that is developed by Gençdoğan (2006) with 44 items, Likert type, and 9 subgroups was used. Sample size was calculated using simple random sampling with a confidence level of 95% and confidence interval of 0.05. A total of 60 participants were included in the study (calculated sample size was 30 for each group). Each group was recorded in the ENMG-UP laboratory using the OIP auditory warning and the "oddball two-tone discrimination task" method. Latency measurements were taken from the highest point of the peak, and amplitude measurements were taken from peak to peak with a cursor. Comparisons of P300 wave latencies obtained via sparse auditory stimulus in PMS and non-PMS groups were made and findings were summarized in one of the tables. Recordings are taken from three scalp regions: parietal and central, respectively. PMS women have longer P300 wave latencies in all regions compared to non-PMS group, whereas there is no significant difference between P300 amplitude.

Neurovegetative disorders of perimenopausal women treated with docosahexaenoic acid (DHA, 625 mg)

The study evaluated the effect of DHA 625 mg in women who experience menopausal symptoms, on sexuality and quality of life (QoL), and on the auditory brainstem response (ABR). Forty-two perimenopausal women were enrolled. The Kupperman Index (KI) was used to evaluate menopause symptoms. The Short Form-36 (SF-36), Female Sexual Function Index (FSFI), and the Female Sexual Distress Scale (FSDS) were used to assess QoL, sexual function, and sexual distress, respectively. Auditory evoked potentials to measure the ABR. The study had one follow-up at 6 months. The women reported an improvement in the KI total score (p < .001). Moreover, women reported QoL improvements in all the psychological categories (p < .001), but not in physical categories (p = NS). FSFI and FSDS total scores increased (p < .01) and the FSDS score decreased (p < .01), mainly due to arousal (p < .03) and lubrication (p < .05) sexual aspects. The ABR wave latencies were lower than the baseline values (p < .05). DHA could be effective in modulating some perimenopausal symptoms in women and, consequently could contribute to improve their QoL and sexual life. Finally, DHA seems to have a direct activity on the neuronal conduction time into the audiological system.

Effects of Spirulina on the functions and redox status of auditory system in senescence-accelerated prone-8 mice

To our knowledge, the effects of Spirulina platensis water extract (SP) on hearing function have not yet been reported. This study investigated the effects of SP on the function and redox status of the auditory system. Auditory brainstem responses and redox status were compared between two groups of 3-month-old senescence-accelerated prone-8 (SAMP8) mice: the control group was fed a normal diet, and the experimental group was fed a normal diet with oral supplementation of SP for 6 weeks. Compared with the control group, the experimental group had significantly lower hearing thresholds according to auditory brainstem responses measured using click sounds and 8-kHz tone burst sound stimulation at the end of this study. The experimental group had a shorter I-III interval of auditory brainstem responses with 16-kHz tone burst stimulation than the control group that was of borderline significance. Additionally, the experimental group had significantly higher mRNA expression of the superoxide dismutase and catalase genes in the cochlea and brainstem and significantly higher mRNA expression of the glutathione peroxidase gene in the cochlea. Further, the experimental group had significantly lower malondialdehyde levels in the cochlea and brainstem than the control group. However, tumor necrosis factor-α mRNA expression was not significantly different between the control and experimental groups. SP could decrease hearing degeneration in senescence-accelerated prone-8 mice possibly by increasing superoxide dismutase, catalase, and glutathione peroxidase gene expression and decreasing damage from oxidative stress in the cochlea and brainstem.

Analysis of gender based differences in auditory evoked potentials among healthy elderly population

BACKGROUND

Influence of gender on auditory evoked potentials is contentious. Although there are quite a few studies documenting the gender as an influencing factor on auditory evoked potentials in younger subjects, but there is a lack of similar studies among elderly population. The present study was conducted to find out the pattern of gender based differences in auditory evoked potentials among healthy elderly subjects.

MATERIALS AND METHODS

A cross-sectional study was conducted on age matched, healthy males (n = 35) and females (n = 34), aged 50-70 years. The measures included latencies of waves I-V and interpeak latencies (IPL) I-III, III-V and I-V separately for both ears. Data was analyzed statistically using Students unpaired t-test, using Statistical Package for Social Sciences software v13.0.

RESULTS

The values of all the latencies and IPL for both the ears were non-significantly higher (P > 0.05) in males as compared to females. These results may be attributed to the differences in head circumference between both the genders and to the changed hormonal milieu of sex hormones after menopause.

CONCLUSIONS

Statistical insignificance of latencies among male and female elderly subjects excludes gender as an influencing factor on auditory evoked potentials in this age group.

Adult plasticity in the subcortical auditory pathway of the maternal mouse

Subcortical auditory nuclei were traditionally viewed as non-plastic in adulthood so that acoustic information could be stably conveyed to higher auditory areas. Studies in a variety of species, including humans, now suggest that prolonged acoustic training can drive long-lasting brainstem plasticity. The neurobiological mechanisms for such changes are not well understood in natural behavioral contexts due to a relative dearth of in vivo animal models in which to study this. Here, we demonstrate in a mouse model that a natural life experience with increased demands on the auditory system - motherhood - is associated with improved temporal processing in the subcortical auditory pathway. We measured the auditory brainstem response to test whether mothers and pup-naïve virgin mice differed in temporal responses to both broadband and tone stimuli, including ultrasonic frequencies found in mouse pup vocalizations. Mothers had shorter latencies for early ABR peaks, indicating plasticity in the auditory nerve and the cochlear nucleus. Shorter interpeak latency between waves IV and V also suggest plasticity in the inferior colliculus. Hormone manipulations revealed that these cannot be explained solely by estrogen levels experienced during pregnancy and parturition in mothers. In contrast, we found that pup-care experience, independent of pregnancy and parturition, contributes to shortening auditory brainstem response latencies. These results suggest that acoustic experience in the maternal context imparts plasticity on early auditory processing that lasts beyond pup weaning. In addition to establishing an animal model for exploring adult auditory brainstem plasticity in a neuroethological context, our results have broader implications for models of perceptual, behavioral and neural changes that arise during maternity, where subcortical sensorineural plasticity has not previously been considered.

Histological evaluation of rat larynx in experimental polycystic ovary syndrome model

This study aimed at studying the histopathological effects of hyperandrogenemia and estrogen deficiency on larynx mucosa in experimentally designed polycystic ovary syndrome of female rats. Two groups of experimental polycystic ovary syndrome model were composed in healthy female rats by per oral letrozole administration of for 21 and 42 days. Also a control group which only took vehicle (saline) for 42 days was designed. Laryngeal mucosa and ovaries of all animals were examined histopathologically by light microscopy and the serum hormone levels were analyzed using a solid-phase, two-site chemiluminescent enzyme immunometric assay. Statistically significant edema, vascular engorgement, inflammation, cilia loss and differentiation of goblet cell distribution were observed when the control group and study groups were compared (p < 0.01). In serum hormonal analysis there was a significant increase in levels of androgens and decrease in levels of estrogens. In addition, polycystic appearance of ovaries in letrozole-administered groups and normal appearance of ovaries in control group have been proven histopathologically. Polycystic ovary syndrome which causes estrogen deficiency and hyperandrogenemia in fertile ages resulted in histopathological changes in laryngeal mucosa.

Pre- and postovulatory auditory brainstem response in normal women

Studies with ovarian hormones on auditory brainstem response (ABR) have conflicting reports although women have ABR shorter than men. This study compared ABR between pre- and postovulatory phases of menstrual cycle in consenting 40 healthy female volunteers (age 19 ± 2.35 years). The study was conducted under standard laboratory conditions (room temperature 26 ± 2°C) using Neuropack (Nihon Kohden machine, NM-420S; H636, Japan) and earphone dynamic receiver ELEGA (Type DR-531; no.237, Japan) in sound proof room. Ears were stimulated simultaneously using standard protocol. ABR was recorded in pre- and postovulatory phases. Ovulation was estimated by measuring basal body temperature. The ABR wave latencies (WLs) I, II, III, IV, V and inter-peak latencies (IPLs) I-III, III-V, I-V were compared between the two phases of menstrual cycle using paired t test. The postovulatory phase had shorter WL V (5.71 ± 0.18 ms vs. 5.81 ± 0.19 ms, p < 0.01), IPL III-V (1.89 ± 0.16 ms vs. 1.94 ± 0.19 ms, p < 0.05), and I-V (3.88 ± 0.16 ms vs. 3.95 ± 0.18 ms, p < 0.05) than in preovulatory. Other WLs and IPLs showed decreasing trend in postovulatory phase. ABR is better in postovulatory phase as compared to preovulatory phase probably due to progesterone hormone which might be involved in modulating auditory hearing pathway at postovulatory phase.

Differences by sex, ear, and sexual orientation in the time intervals between successive peaks in auditory evoked potentials

Auditory evoked potential (AEP) data from two studies originally designed for other purposes were reanalyzed. The auditory brainstem response (ABR), middle-latency response (MLR), and long-latency response (LLR) were measured. The latencies to each of several peaks were measured for each subject for each ear of click presentation, and the time intervals between successive peaks were calculated. Of interest were differences in interpeak intervals between the sexes, between people of differing sexual orientations, and between the two ears of stimulation. Most of the differences obtained were small. The largest sex differences were for interval I → V in the ABR and interval N1 → N2 of the LLR (effect sizes > 0.6). The largest differences between heterosexuals and nonheterosexuals were for the latency to Wave I in both sexes, for the interval Na → Nb in females, and for intervals V → Na and Nb → N1 in males (effect sizes > 0.3). The largest difference for ear stimulated was for interval N1 → N2 in heterosexual females (effect size ∼0.5). No substantial differences were found in the AEP intervals between women using, and not using, oral contraceptives. Left/right correlations for the interpeak intervals were mostly between about 0.4 and 0.6. Correlations between the ipsilateral intervals were small; i.e., interval length early in the AEP series was not highly predictive of interval length later in the series. Interpeak intervals appear generally less informative than raw latencies about differences by sex and by sexual orientation.

Characteristics of nasal epithelial cells in naturally postmenopausal women receiving hormone therapy with 1 mg 17beta-estradiol and 2 mg drospirenone: a prospective study

OBJECTIVE

To investigate the effects of drospirenone on nasal respiratory epithelium in postmenopausal women who are treated with hormone therapy (HT).

DESIGN

Thirty-five naturally postmenopausal women participated in the prospective study. Women received continuous-combined HT containing 1 mg 17beta-estradiol and 2 mg drospirenone. Cytological changes of nasal middle and inferior turbinate respiratory epithelium were evaluated by using the maturation index, performed at baseline and on the sixth cycle of HT.

RESULTS

Hematoxylin-eosin staining for the maturation index of the epithelial nasal cells of women reached better trophic aspects during 17beta-estradiol/drospirenone intake with respect to those observed at baseline (P < 0.001). The smears during HT emphasized the superficial and the intermediate types of cells, with a ratio index greater than 2. The parabasal cell content was less than 20%, and the karyopyknotic index showed degenerative changes in superficial and intermediate cells.

CONCLUSIONS

Our study confirmed that the nasal respiratory epithelium is an ovarian steroid target. Drospirenone acts on nasal cells similarly to other progestogens.

Prospective study on the cytological aspects of the nasal respiratory epithelium in premenopausal women taking 30 mcg ethinylestradiol and 3 mg drospirenone oral contraceptive

BACKGROUND

This study was conducted to determine the effects of the monophasic oral contraceptive (OC) containing 30 mcg ethinylestradiol (EE) and 3 mg drospirenone (DRSP) on the nasal respiratory epithelium in premenopausal women.

STUDY DESIGN

Fifty premenopausal women participated in the prospective study. Baseline endovaginal ultrasound examination and blood test to measure serum progesterone to confirm an ovulatory cycle were performed. The cytologic changes on the nasal respiratory epithelium were evaluated with the maturation index, performed during the follicular, periovular and luteal phases of the menstrual cycle, and on the sixth cycle of pill intake.

RESULTS

The maturation indexes of the nasal smears were higher during both the follicular and periovular phases than during the luteal phase of the menstrual cycle (p<.05). Women on the OC pill had similar changes in the nasal epithelium as those seen during the follicular phase (p NS), and less than the periovular phase (p<.05) and higher than the luteal phase (p<.05). The maturation index of the nasal respiratory epithelium seems to depend on the variation of the ovarian steroids during the menstrual cycle and on the iatrogenic effects of oral contraception.

CONCLUSIONS

DRSP+EE seems to provoke cytological changes that are different from previously shown gestodene plus EE.

Cytological aspects of the nasal respiratory epithelium in reproductive-age women taking oral contraceptives

OBJECTIVE

To determine the effects of monophasic oral contraceptives on the nasal respiratory epithelium in premenopausal women.

DESIGN

Prospective open clinical trial.

SETTING

Outpatient Family Planning Centre.

PATIENT(S)

Eighty-eight premenopausal women, with ovulatory cycle, who were planning to take oral contraceptives.

INTERVENTION(S)

Baseline endovaginal ultrasound examination and blood test to measure serum progesterone to confirm ovulatory cycle. Thirty-eight women on pill containing 30 microg ethinylestradiol (EE) plus 75 microg gestodene, and 35 women on pill containing 15 microg ethinylestradiol plus 60 microg gestodene. MAIN OUTCOMES/MEASURE(S): Cytological changes on the nasal respiratory epithelium evaluated with the maturation index performed during the follicular, periovular, and luteal phases of the menstrual cycle, and on the sixth cycle of pill intake.

RESULT(S)

Hematoxylin-eosin staining for the maturation index showed similar trophic cytological aspects between the nasal and vaginal epithelium during the menstrual cycle and pill usage. Both the nasal and vaginal cytological samples showed higher maturation indexes during both the follicular and the periovular phases than during the luteal phase. Women on pill containing 15 microg EE showed lower trophic aspects in the nasal cytological samples compared with those on pill with 30 microg EE.

CONCLUSION(S)

Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target. The maturation index of the nasal respiratory epithelium seems to depend on the variation of the ovarian steroids during the menstrual cycle and on the iatrogenic effects of oral contraceptives.

Age-related cognitive decline in the menopause: effects of hormone replacement therapy on cognitive event-related potentials

OBJECTIVE

Although epidemiological and clinical studies suggest that hormone replacement therapy (HRT) may protect against cognitive disorders and neurodegenerative diseases, the relation between estrogen and cognition in postmenopausal women remains controversial.

METHODS

In a double-blind placebo-controlled, parallel group design study the effects of HRT with the estrogen-progestogen combination Presomen 1.25 compositum((R)) (1.25mg equine conjugated estrogens administered for 21 days plus the progestogen 5mg medrogeston given for 11 days) on event-related potentials (ERPs) in postmenopausal patients with age-related cognitive decline (DSM-IV code 780.9, ICD-10 code R 41.8) were investigated. After a pre-drug comparison with age-matched normal postmenopausal controls, 48 psychotropic drug-free patients aged 60 +/- 6 years were randomized to receive either placebo or verum for 4 months. ERPs were recorded before as well as on the 91-92 days of the study, which thus fell into the estrogen phase of the treatment during the fourth cycle.

RESULTS

At baseline, patients showed a lengthening of P300 latency and an attenuation of P300 amplitudes as compared with normal controls. After HRT with Presomen, a significant shortening of P300 latency as compared with placebo was observed.

CONCLUSIONS

The baseline P300 differences suggest that in the patient group the aging process was advanced, while after HRT with Presomen a significant improvement and normalization of information processing as indexed by P300 was observed.

No changes in event-related potentials with estrogen or estrogen plus progesterone treatment in healthy older hysterectomized women: results from a double-blind, placebo-controlled study

RATIONALE

The potential to improve cognition in older women with estrogen or estrogen/progesterone therapy is currently a matter of intense debate. Only a few studies conducted so far have used electrophysiological indicators of cognitive information processing as outcome measures in randomised placebo controlled studies.

OBJECTIVES

This study was undertaken to measure changes in event-related potentials (ERPs) after short (4 weeks) or prolonged (24 weeks) hormone treatment in older women.

METHODS

A randomised, double-blind, placebo-controlled study in hysterectomized older women (aged 58-75 years) was performed (n = 51). The participants received orally estradiol (2 mg estradiol valerate), estradiol plus progesterone (100 mg micronized progesterone) or placebo for 24 weeks. Using four different paradigms, early and late ERPs were assessed at baseline and after 4 and 24 weeks of treatment.

RESULTS

Strong hormone increases were observed in the two active treatment groups. However, no significant effects on any of the assessed ERPs were observed in either of the two treatment groups. Similar non-significant findings were obtained for reaction time and error rate.

CONCLUSIONS

Estradiol or estradiol/progesterone treatment appears to have no strong effects on several ERP markers of information processing in older hysterectomized women. The current negative findings might suggest a reduced sensitivity of the aged brain to gonadal steroids.

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.

Cytologic aspects of the nasal respiratory epithelium throughout the menstrual cycle

A prospective study was performed to investigate the changes in nasal cytology that occur in healthy premenopausal women throughout the menstrual cycle. Eighty-eight women with an ovulatory menstrual cycle underwent nasal sampling with a cytobrush by direct vision of the middle and inferior nasal turbinates during the follicular, periovular, and luteal phases of the menstrual cycle, and the specimens were evaluated with the maturation index. Hematoxylin-eosin staining showed the cytologic aspects of the nasal respiratory epithelium and of vaginal smears according to the three different phases of the menstrual cycle. Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target.

Testosterone reduces responsiveness to nociceptive stimuli in a wild bird

The hormone testosterone (T) is involved in the control of aggressive behavior in male vertebrates. T enhances the frequency and intensity of aggressive behaviors during competitive interactions among males. By promoting high-intensity aggression, T also increases the risk of injury and presumably the perception of painful stimuli. However, perception of painful stimuli during fights could counteract the expression of further aggressive behavior. We therefore hypothesize that one function of T during aggressive interactions is to reduce nociception (pain sensitivity). Here, we experimentally document that T indeed reduces behavioral responsiveness to a thermal painful stimulus in captive male house sparrows (Passer domesticus). Skin nociception was quantified by foot immersion into a hot water bath, a benign thermal stimulus. Males treated with exogenous testosterone left their foot longer in hot water than control birds. Conversely, males in which the physiological actions of testosterone were pharmacologically blocked withdrew their foot faster than control birds. Testosterone might exert its effects on pain sensitivity through conversion into estradiol in the dorsal horn of the spinal cord. Decreased nociception during aggressive encounters may promote the immediate and future willingness of males to engage in high-intensity fights.

Effects of prolonged exposure to an augmented acoustic environment on the auditory system of middle-aged C57BL/6J mice: cochlear and central histology and sex differences

Genetic progressive sensorineural hearing loss in mice of the C57BL/6J (B6) inbred strain begins at high frequencies during young adulthood and is severe by 12 months (middle age). Nightly treatment with an augmented acoustic environment (AAE)--12-hour periods of exposure to repetitive noise bursts of moderate intensity, begun at age 25 days--resulted in less severe hearing loss compared with control mice. Cochlear histopathological correlates of AAE treatment, assessed at 12-14 months of age, included lessened severity of progressive loss of outer hair cells in both sexes as well as small savings of spiral ganglion cells in females and inner hair cells in males. AAE effects on the number of surviving neurons (age 12-14 months) in the anterior ventral cochlear nucleus (AVCN) depended on sex. Compared with controls, the loss of AVCN neurons that typically accompanies the initial period of hearing loss (between 2 and 7 months of age) was not significantly affected by AAE treatment in females. In contrast, males treated with the AAE exhibited more severe loss of neurons in the dorsal and ventral extremes of the AVCN than male controls of the same age. AAE treatment begun at age 3-5 months resulted in significant but less severe loss of AVCN neurons in 1-year-old male mice.

Immunocytochemical localization of aromatase in sensory and integrating nuclei of the hindbrain in Japanese quail (Coturnix japonica)

The distribution of the estrogen synthesizing enzyme (aromatase) in the hindbrain (rhombencephalon and mesencephalon) of male adult quail was investigated by immunocytochemistry. Aromatase-immunoreactive neuronal structures (perikarya and fibers bearing punctate structures) were observed in sensory (trigeminal, solitary tract, vestibular, optic tectum) and integrating (parabrachial, periaqueductal, cerulean, raphe) nuclei. Besides the expression of aromatase in these well-delineated nuclei, dense to scattered networks of immunoreactive fibers were found dispersed throughout the hindbrain and, in particular, in its rostral and dorsal parts. To a lesser extent, they were also present throughout the premotor nuclei of the reticular formation and in various fiber tracts. In contrast, no immunoreactive signal was found in motor nuclei, and in most of the statoacoustic (cerebellum, cochlear, olive, pontine, part of vestibular) nuclei. The expression of aromatase in perikarya and fibers in areas of the adult hindbrain where estrogen receptors have been identified previously suggests a role for estrogens locally produced in the regulation of sensory and integrating functions, contrary to the widespread assumption that these functions are regulated exclusively by steroids produced in the gonads.

Auditory brain stem response throughout the menstrual cycle

A prospective study was performed to evaluate the changes in the auditory brain stem response (ABR) that occur in healthy premenopausal women throughout the menstrual cycle. Ninety-four women with ovulatory menstrual cycles underwent ABR testing by auditory evoked potentials for wave I, III, and V latencies and for interpeak I-III, I-V, and III-V intervals during the follicular, periovular, and luteal phases of the menstrual cycle. The wave latencies and the interpeak intervals showed shorter values during the periovular phase than during the luteal phase (p < .05) and shorter values during the follicular phase for wave I (p < .05) and interpeak interval I-V (p < .05). The ABR seems to be influenced by the variations of ovarian steroids that occur during the menstrual cycle.

Effects of hormone replacement therapy on perceptual and cognitive event-related potentials in menopausal insomnia

The influence of a combined estrogen-progestin regimen (Climodien, Lafamme) on auditory event-related potentials (ERPs) was investigated in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase (Climodien 2/3=estradiol valerate 2 mg+the progestin dienogest 3 mg, EV=estradiol valerate 2 mg, and placebo), followed by an open-label phase in which all patients received Climodien 2/2 (estradiol valerate 2 mg+dienogest 2 mg). Both the double-blind and the open-label phase lasted 2 months. ERPs were recorded from 19 EEG leads in a two-tone odd-ball paradigm in 49 patients aged between 46 and 67 yr with the diagnosis of insomnia (G 47.0) related to postmenopausal syndrome (N 95.1). Climodien reduced standard N1 and target P300 latencies as compared to placebo, while EV did not affect N1 latency but similarly reduced P300 latency. Climodien increased N1, P2 and P300 amplitudes dose-dependently, predominantly at frontal leads. Estrogen alone had only minor effects on ERP amplitudes. The shortening of standard N1 latency and enhancement of N1 and P2 amplitudes indicates a positive effect of Climodien on perceptual processing, most likely due to vigilance improvements also observed in EEG mapping. Concerning target P300, it seems that estradiol is responsible for the improvement in stimulus evaluation time, as reflected by the shortening of the peak latency, while dienogest seems to account for the improvement in cognitive information processing capacity, whereby 3 mg induced a more pronounced augmentation of P300 amplitudes than 2 mg. Based on the spatial distribution of this increase, it can be speculated that Climodien mainly affects the more frontally distributed P3a subcomponent, which is associated with attention and orientation. Furthermore, the observed changes in ERP-components are consistent with recent studies showing significant positive effects of hormone replacement therapy on cholinergic functions. Thus, Climodien seems to be of interest in preventing cognitive decline and treating cognitive disorders in postmenopausal women. Indeed, there is increasing evidence of beneficial effects of estrogen in dementia. Our present findings suggest that the estrogen effects may be augmented by dienogest.

Cytologic aspects of the nasal respiratory epithelium in postmenopausal women treated with hormone therapy

OBJECTIVE

To investigate the effects of hormone therapy (HT) on nasal respiratory epithelium in postmenopausal women.

DESIGN

Prospective open clinical trial.

SETTING

Outpatient menopausal clinic.

PATIENT(S)

One hundred three healthy postmenopausal women, of whom 55 treated with HT, and 48 untreated women (controls).

INTERVENTION(S)

Different regimens of HT by patch, gel, or oral administration.

MAIN OUTCOME MEASURE(S)

Cytologic changes of nasal, middle and inferior turbinate cells compared with vaginal cytologic findings by using the maturation index.

RESULT(S)

Hematoxylin-eosin staining for the maturation index confirmed similar trophic cytologic aspects between the nasal respiratory epithelium and vaginal smears in HT-treated women and controls. Women treated with sequential HT or estrogen therapy (ET) showed better trophic characteristics in the nasal cytological samples compared with women treated with continuous combined HT.

CONCLUSION(S)

Along with vaginal cells the nasal respiratory epithelium is an estrogen target. The activity of HT in the nasal respiratory epithelium may depend on the type of hormone regimen used.

Effects of patch or gel estrogen therapies on auditory brainstem response in surgically postmenopausal women: a prospective, randomized study

OBJECTIVE

To study the effects of gonadal steroids on the nongenital audiological target in surgically postmenopausal women treated with patch or gel transdermal estrogen therapy (ET).

DESIGN

Prospective randomized study.

SETTING

Research Group for Sexology, University of Catania, Italy.

PATIENT(S)

One hundred twenty-two surgically postmenopausal women.

INTERVENTION(S)

Transdermal E(2) by patch or gel, and evaluation of auditory brainstem response by auditory-evoked potentials for waves I, III, and V latencies, and for interpeak I-III, I-V, and III-V intervals.

MAIN OUTCOME MEASURE(S)

Changes in auditory wave latencies and in interpeak intervals during treatment with ET with respect to baseline levels.

RESULT(S)

One hundred two women completed the study. Forty-eight subjects used E(2) patches and 54 E(2) gel. No significant difference was observed in plasma E(2) improvement and in auditory brainstem response values with the two estrogen (E) formulations. The wave latencies and the interpeak intervals showed lower values during the E treatment than at baseline.

CONCLUSION(S)

Auditory brainstem response seems to depend on the type of E given. Our data suggest that fluctuating E levels act on waves, even if the exact mechanism of the gonadal steroids is not clear. However, we believe that E could influence neuronal plasticity, the metabolic levels of neurotransmitters, and thus, the neuronal conduction time into the audiological system.

Auditory brainstem response in premenopausal women taking oral contraceptives

BACKGROUND

The aim of this prospective study was to evaluate the effects of the new monophasic oral contraceptives on the audiological system in premenopausal women.

METHODS

The auditory brainstem response (ABR) was measured in 94 women during the follicular, periovular and luteal phases of one menstrual cycle in which ovulation was confirmed using sonography and serum progesterone concentration. The latencies for waves I, III and V were determined, and the inter-peak intervals were calculated for waves I-III, I-V and III-V. All 94 women began taking oral contraceptives: 23 women used 20 microg ethinyl estradiol (EE) plus 150 microg desogestrel, 24 women used 30 microg EE plus 75 microg gestodene, and 47 women used 15 microg EE plus 60 microg gestodene. During the third month of contraceptive intake, each subject was again tested for ABR, as above.

RESULTS

The wave latencies and inter-peak intervals showed shorter values during the periovular phase with respect to the luteal phase (P < 0.05), the follicular phase for wave I and for inter-peak interval I-V (P < 0.05) of the menstrual cycle. All of the ABR results in pill users were statistically different from those of the periovular phase (P < 0.05), though similar to those of both the luteal and follicular phases (P = NS).

CONCLUSIONS

ABR seems to depend on the variations of ovarian steroids during the menstrual cycle and during oral contraceptive intake.