Ablation of luteal phase symptoms of Menière's disease with leuprolide

Influence of sex hormones on vestibular disorders

PURPOSE OF REVIEW

Vestibular disorders are gender distributed with a higher prevalence in women. Although research has increased in this field, the mechanisms underlying this unbalance is unclear. This review summarises recent advances in this research sphere, and briefly discusses sex hormone effects on various vestibular conditions and highlights some recent theories.

RECENT FINDINGS

Recent work has identified a direct link between aberrant gonadal hormone levels and vestibular dysfunction. Benign paroxysmal positional vertigo research suggests that the disorder may be linked to the rapid decrease in oestrogen, observed in menopausal women, which disrupts otoconial metabolism within the inner ear. A successful hormonal therapeutic intervention study has advanced our knowledge of hormonal influences in the inner ear in Ménière's disease. Also, several studies have focused on potential mechanisms involved in the interaction between Vestibular Migraine, Mal de Debarquement Syndrome, and gonadal hormones.

SUMMARY

In females, gonadal hormones and sex-specific synaptic plasticity may play a significant role in the underlying pathophysiology of peripheral and central vestibular disorders. Overall, this review concludes that clinical assessment of female vestibular patients requires a multifaceted approach which includes auditory and vestibular medicine physicians, gynaecologists and/or endocrinologists, in conjunction with hormonal profile evaluations.

Effects of combined oral contraception containing drospirenone on premenstrual exacerbation of Meniere's disease: Preliminary study

OBJECTIVES

Meniere's disease is caused by an augmented endolymph pressure in the inner ear; symptoms are vertigo, fluctuating hearing loss and tinnitus. Exacerbations has been noted during premenstrual phase. The study aims to evaluate the effects of a 20 μm Ethinylestradiol (EE) and 3 mg Drospirenone (DRSP) oral contraceptive (20 μmEE/3mgDRSP) in continuous regimen, associated with rehabilitation therapy on Meniere's disease.

STUDY DESIGN

This non-randomized controlled study was performed from October 2015 to October 2017. Forty-two premenopausal women affected by MD with severe distress in the premenstrual phase were enrolled. Sixteen women constituted the study group (Group A), and twenty women constituted the control group (Group B). Group A underwent EE/DRSP therapy and rehabilitation and Group B underwent rehabilitation therapy alone. Stabilometry and the Dizziness Handicap Inventory questionnaire were used to measure vestibular function and distress related to the disease, respectively, at baseline (T0), 3 months (T1) and 6 months (T2).

RESULTS

At T0, both groups had large, similar areas of stabilometric ellipses (p = NS) that reduced more in Group A than in Group B, at T1 and T2 (p < 0.001). High scores of the DHI (cut-off ≤54) were observed at T0 in both groups (A 66.8 ± 2.8 vs B 65.5 ± 3.6; p = NS). At T1, a gradual improvement in both groups was observed, manly in Group A (A 45.1 ± 3.6 vs B 62.4 ± 4.1; p < 0.001). At T2, the DHI scores were significantly lower in Group A (39.2 ± 3.8) compared to Group B (68.8 ± 3.6) (p < 0.001).

CONCLUSIONS

DRSP could be effective in reducing the fluid overload typical of the premenstrual phase, improving symptoms of MD. The results support the efficacy of EE/DRSP usage associated with rehabilitation therapy on premenstrual exacerbation of MD.

Improvement in Sensorineural Hearing Loss During Pregnancy

Objective:

Hearing loss is known to occur in some pregnant women, but improvement in sensorineural thresholds has not been audiometrically characterized. Here, we describe a patient with a history of Ménière’s disease and vestibular migraine who experienced temporary recovery of her hearing during pregnancy.

Methods:

Audiograms were obtained from a 31-year-old female over the course of 2 successive pregnancies.

Results:

Audiograms revealed a substantial improvement in hearing by the third trimester during each pregnancy, with a rapid return to baseline thresholds after delivery.

Conclusion:

This case is unique in documenting improvements in hearing thresholds during pregnancy and substantiates the effects of hormonal changes on hearing thresholds in humans. It raises the intriguing possibility of hormonal therapy as a treatment for sensorineural hearing loss in specific clinical situations.

Immunohistochemical localisation and molecular expression of the steroidogenic enzyme cytochrome P450 17α-hydroxylase /C(17,20)-lyase in the vestibular nuclei of adult male rats

Many biologically active neurosteroids, including dehydroepiandrosterone (DHEA), are synthesised in the brain. DHEA is a potent endogenous modulator of several neuronal functions, and alterations of DHEA are correlated with various neurobiological deficits. The cytochrome P450 17α-hydroxylase/C(17,20)-lyase (P450C(17) ) plays a pivotal role in the synthesis of DHEA from pregnenolone and progesterone. We investigated the immunohistochemical localisation and molecular expression of P450C(17) in the superior, lateral, medial and inferior vestibular nuclei (VCN) of adult male rats by western blotting and indirect immunofluorescence analysis. Immunoreactive P450C(17) was widely distributed in all VCN and the expression of P450C(17) was confirmed by western blot analysis. The present study demonstrates, for the first time, the presence and anatomical distribution of P450C(17) in the VCN. Given that neurosteroids can modulate neuronal activities in the medial vestibular nucleus, DHEA synthesised in the VCN may play an important role in the control of specific activities at this level.

Medical and noninvasive therapy for Meniere's disease

Nonoperative therapy continues to be the mainstay of treatment of patients suffering from Meniere disease. Despite extensive research, the exact pathogenesis of Meniere disease remains elusive. The poorly understood nature of this condition has made it nearly impossible to develop treatments that are curative. Most modern treatments are aimed at controlling symptoms. This article reviews the various nonoperative treatments that have been used to treat Meniere disease historically as well as outlining the authors' clinical treatment paradigm.

History of Meniere's disease and its clinical presentation

The term Meniere's disease is used to define either the classic triad of vestibular and cochlear symptoms and aural pressure from known or unknown causes or its clinical variants, vestibular and cochlear Meniere's disease. Some variants evolve after years into typical forms, whereas others do not. Some symptoms (positional vertigo) have been long underestimated in previous reports. The more we study our patients and correlate clinical findings and the natural history with pathologic studies on temporal bones and laboratory research, the more we will understand Meniere's disease and its causes. Some causes have already been identified as most probable. Extrinsic factors (inflammation, trauma, otosclerosis, autoimmunity, endocrine disorders, and such) interact with congenital (genetic) and developmental intrinsic factors (primary or secondary, acquired) into a multifactorial inheritance that is, to date, the best explanation for the basis of Meniere's disease. Endolymphatic hydrops is widely accepted as the pathologic substrate, but not all hydrops seems to be progressive or becomes clinically manifest. Endolymphatic hydrops is the result of a dysfunction in the mechanism of production/absorption of endolymph, which is mainly due to defective absorptive activity of the endolymphatic duct and sac. Hyperproduction of endolymph cannot be excluded in some cases. Ruptures of the labyrinthine membranes do not satisfactorily substantiate the multiform duration, recurrence, and repetitiveness of attacks of Meniere's disease, nor do they explain the entire complex of symptoms. It seems reasonable to explain symptoms of Meniere's disease on the basis of mechanical factors (as observed in temporal bone studies) associated with biologic and biochemical factors.

Changes in Ménière's disease responses as a function of the menstrual cycle

BACKGROUND

Ménière's disease is a complex, progressive disorder of the inner ear evidenced by characteristic responses including vertigo, hearing loss, and tinnitus. Though considered equally common across sexes, several recent studies describe women's increasing reports of symptom exacerbation during the perimenstruum. Empirical evidence proving this relationship is limited with no study exploring women's symptom reports using appropriate methodological procedures for menstrual cycle research.

OBJECTIVES

To establish the relationship between menstrual cycle phases and Ménière's disease responses. Specific aims included comparison of Ménière's disease responses between menstruant women and men (control group) and examination of women's Ménière's disease responses and their relationship to their diverse menstrual symptom patterns.

METHODS

Using a longitudinal, descriptive design, 12 men and 13 women were recruited via Internet and participated in daily data collection procedures over three study phases.

RESULTS

Results showed that Ménière's disease responses were similar for men and women participants. Women with premenstrual magnification patterns did not vary with cycle phases. However, vertigo (P < .05) did decrease significantly postmenses for women with premenstrual syndrome patterns.

CONCLUSIONS

Results from this study provide evidence that a unique relationship does exist between the menstrual cycle and Ménière's disease responses for some women. Knowledge gained from this study is beneficial in identifying the importance of appropriate clinical assessment methods of menstruant women with Ménière's disease. Recommendations include further research with larger samples and testing of different symptom management strategies for women of different perimenstrual symptom patterns.

The endocrine system, vertigo and balance

Steroid, amine and peptide hormones affect the peripheral vestibular system. Vasopressin hypersensitivity of the endolymphatic sac may be implicated in the pathogenesis of Meniere's disease. Specific vasopressin antagonists will help define the role of vasopressin in Meniere's disease. The modulation of central vestibular pathways by neuroactive steroids may involve effects on gamma-aminobutyric acid-ergic and glutaminergic pathways. The vestibular nuclei also express enzymes that are important in the synthesis of steroids and the modulation of their activity. Steroids mediate both facilitatory and deleterious effects of stress on vestibular compensation. The quality and quantity of stressor that determines the pattern of hormonal output, may be important. Clinical observation suggests that episodic ataxia type 2, a P/Q calcium channelopathy, may be phenotypically modulated by endocrine fluctuations. Steroid hormones may affect the episodic ataxia type 2 phenotype by modulation of voltage-gated calcium channel activity via second messenger systems and ion channel subunit expression. Despite evidence to support the link, the role of the endocrine system in vestibular function and disease is as yet virtually unexplored.

Absence of mRNA encoding estrogen receptor in the rat cochlea

Based on changes in hearing thresholds and tinnitus that are co-related with the menstrual cycle, it has been suggested that the cochlea may respond directly to estrogen. For this to occur, the cochlea should express estrogen receptors. In situ mRNA hybridization was performed on normal female rat cochleas, using radiolabeled RNA probes complementary to mRNA encoding estrogen receptor, to determine whether estrogen receptors are present in the cochlea. Strong hybridization of the riboprobes to sections of uterus and hypothalamus indicated that the technique detected estrogen receptor mRNA. No hybridization to any cochlear tissues was observed. The results indicate that estrogen receptors are not expressed on cochlear cells, at least in rats. This in turn suggests that variation in cochlear responses during the estrus cycle are not the result of the direct effect of estrogen on the cochlea. Such variation may, however, be caused by systemic changes in fluid regulation induced by estrogen receptors at a distant site, or by other hormone receptors.

Leuprorelin. A review of its pharmacology and therapeutic use in prostatic cancer, endometriosis and other sex hormone-related disorders

Leuprorelin (leuprolide acetate) is a gonadotrophin-releasing hormone (GnRH) analogue used to treat a wide range of sex hormone-related disorders including advanced prostatic cancer, endometriosis and precocious puberty. It acts primarily on the anterior pituitary, inducing a transient early rise in gonadotrophin release. With continued use, leuprorelin causes pituitary desensitisation and/or down-regulation, leading to suppressed circulating levels of gonadotrophins and sex hormones. Clinical trials in men with advanced prostatic cancer demonstrate that leuprorelin (usually monthly depot injections of 3.75 or 7.5 mg) is less likely to cause serious adverse cardiovascular effects than diethylstilbestrol, and has comparable efficacy to bilateral orchiectomy or other GnRH analogues. Therefore, the choice between leuprorelin and orchiectomy may be made on the basis of the patient's treatment preference, along with specific patient characteristics and cost implications. Monthly intramuscular or subcutaneous administration of depot leuprorelin 3.75 mg was superior to placebo, and comparable to oral danazol 800 mg/day or intranasal buserelin 900 micrograms/day, in achieving objective and subjective responses in women with endometriosis. Thus, leuprorelin is an effective alternative to other treatments for women with endometriosis, but the recommended duration of its use in this clinical setting is limited to 6 months because it reduces bone mineral density. In children with central precocious puberty, leuprorelin (usually monthly intramuscular or subcutaneous injections of depot leuprorelin 3.75 to 15mg) decreases mean growth velocity and signs of sexual maturation and increases predicted adult height compared with baseline measurements. Although effects on final adult height are predicted from available data and require confirmation in long term follow-up studies, the absence of effective alternatives to GnRH analogues makes leuprorelin a first-line therapy for children with this rare disease. In women with uterine leiomyomata, monthly intramuscular administration of depot leuprorelin 3.75 mg for 6 months markedly reduces uterine volume and fibroid-related symptoms, but, as with other GnRH analogues, these effects dissipate following discontinuation of the drug. As adjuvant therapy in women undergoing in vitro fertilisation or gamete intrafallopian transfer, leuprorelin (usually 0.5 to 1 mg/day subcutaneously) reduces the risk of cancelled cycles for oocyte retrieval by preventing premature luteinisation. While some studies demonstrate an improvement in intermediate end-points such as increased number of mature oocytes retrieved and embryos available for transfer, a significant effect has not been demonstrated on the rate of live births per stimulated cycle.(ABSTRACT TRUNCATED AT 400 WORDS)