Hormone therapy and ophthalmic artery blood flow changes in women with primary open-angle glaucoma

Impact of primary glaucoma on health-related quality of life in China: the handan eye study

BACKGROUND

We assessed health-related quality of life (HRQOL) and its determinants among rural glaucoma participants compared to age-matched normal controls in the population-based Handan Eye Study (HES), in rural Yongnian County, northern China.

METHODS

We enrolled 99 adults with glaucoma (mean age 63.0 ± 11.0 years), including primary open-angle glaucoma (POAG, n = 67) and primary angle-closure glaucoma (PACG, n = 32) and 102 controls (mean age 58.5 ± 5.3 years) with normal visual acuity and visual field and no history of glaucoma. Results of ophthalmic examinations and socioeconomic data were recorded. HRQOL was measured using the EQ-5D (converted to utility valves, UVs), and visual function (VF) and vision-related quality of life (VRQOL) were evaluated using the visual function-quality of life (VF-QOL) instrument.

PRIMARY AND SECONDARY OUTCOME MEASURES

EQ-5D and VF-QOL scores.

RESULTS

The mean UVs, VF, and VRQOL scores for glaucoma cases were 0.98 ± 0.04, 87.9 ± 15.2, and 95.5 ± 12.8, respectively, significantly worse than VF (94.4 ± 4.4) and VRQOL (100.0 ± 0.0) among controls, even after adjusting for age, gender, educational level, and family income (P = 0.015, P = 0.033). UVs were significantly lower among glaucoma participants with impaired VRQOL (55.4 ± 11.5) compared to those with normal VRQOL scores (99.1 ± 2.8) (UVs: 0.92 ± 0.08 vs. 0.99 ± 0.03, P = 0.036), also after adjustment for age and family income (P = 0.006). Participants with PACG had significantly lower VF and VRQOL scores compared to POAG (77.8 ± 21.4 vs. 92.9 ± 6.8, P < 0.001; 89.0 ± 18.1 vs. 98.7 ± 7.5, P < 0.001).

CONCLUSION

Participants with glaucoma have worse visual function and related quality of life compared to age-matched normal population controls. Participants with PACG have lower VF and VRQOL compared to those with POAG. UVs can be used for cost-effectiveness research and to support public health strategies for glaucoma in rural China.

Hormone Replacement Therapy and the Incidence of Nonarteritic Anterior Ischemic Optic Neuropathy: a Nationwide Population-Based Study (2009-2018)

PURPOSE

This study aimed to assess the association between hormone replacement therapy (HRT) and the prevalence of nonarteritic anterior ischemic optic neuropathy (NAION) in menopausal women using national data from the entire Korean population.

METHODS

The health screening data of 1,381,605 women between 40 and 90 years of age collected by the National Health Insurance Service (NHIS) of Korea between January 1, 2009, and December 31, 2018, were retrospectively reviewed. Before data analysis, the potential cofounders were adjusted for among all participants. Based on HRT use and its duration (classified into four groups), the hazard ratio (HR) and 95% confidence interval (CI) of NAION development were calculated via a Cox proportional hazards regression analysis using the nonuser group as a reference.

RESULTS

Overall, 7824 NAION diagnoses were made during the mean follow-up of 8.22 years (standard deviation: 1.09 years) in 1,381,605 post-menopausal women. NAION was more common in the HRT group than in the non-HRT group (HR [95% CI]: 1.268 [1.197-1.344]). Furthermore, the risk of NAION increased along with increased HRT duration (p < 0.0001). In the multivariate analysis, the adjusted HRs of the < 2-year HRT group, the 2-5-year HRT group, and the ≥ 5-year HRT group were 1.19 (95% CI: 1.10-1.28), 1.3 (95% CI: 1.17-1.45), and 1.473 (95% CI: 1.31-1.65), respectively. Compared to women younger than 65 years, the HR of HRT for NAION was significantly higher than that of women older than 65 years (p < 0.0001).

CONCLUSION

Our population-based cohort study found that HRT was significantly associated with increased incidence of NAION. The incidence of NAION also increased with the duration of HRT.

Evaluation of the relationship between plasma viscosity and selected menopausal symptoms using the Menopause Rating Scale

OBJECTIVE

The aim of this study was to investigate whether whole blood viscosity and plasma viscosity are associated with the severity of postmenopausal symptoms using the Menopause Rating Scale (MRS).

METHODS

This study included 108 postmenopausal women admitted to menopause clinics. Participants were divided into two groups according to their MRS scores. Groups 1 (n = 52) and 2 (n = 56) were composed of healthy postmenopausal women with MRS scores of <14 and ≥14 points, respectively. The clinical findings and hemorheological parameters were compared between the two groups.

RESULTS

Comparing plasma viscosity levels between the two groups showed that group 1 had 1.25 ± 0.08 centipoise, whereas group 2 had 1.30 ± 0.10 centipoise ( P = 0.03). The difference in plasma viscosity between the two groups persisted after adjustment for age (1.24 ± 0.08 vs 1.31 ± 0.10; P < 0.001). Plasma viscosity was also significantly correlated with age ( r = 0.384, P < 0.001), menopausal duration ( r = 0.362, P < 0.001), and urogenital symptoms ( r = 410, P < 0.001).

CONCLUSIONS

Increased plasma viscosity levels were significantly associated with selected postmenopausal symptoms, independent of age.

Characteristics of Visual Field Defects in Korean Advanced Glaucoma

Purpose: We investigated the clinical characteristics of visual field (VF) defects in Korean advanced glaucoma patients.Methods: The present study included 109 eyes of 109 advanced glaucoma patients whose mean deviation (MD) is under -12 dB. The subjects were classified into primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) group. Average numeric decibel in each VF points were visualized with color topographic image and dot graph image using python 3.5. VF was divided into four quadrants or two half fields, and the differences in the degree of VF defects in each locations were assessed with raw decibel data. Additionally, mean sensitivity of central 12 points were compared between the two groups.Results: Generally the features of VF defects were severely depressed VF sensitivity at the superonasal quadrant and relatively preserved central area and inferotemporal quadrant in both of the glaucoma groups. But we found the extent of deflection for VF defect in the NTG eyes was higher than that of the POAG eyes (p < 0.05). The POAG eyes tended to show more diffuse and evenly distributed VF defect, whereas NTG eyes tended to have more severely depressed VF at the superonasal quadrant and relatively preserved VF at the inferotemporal quadrant. There was no significant difference in the degree of central VF defects between the two groups.Conclusions: The characteristics of VF defect in Korean advanced glaucoma revealed different features based on the glaucoma diagnosis. The POAG eyes tended to show diffuse VF defects, whereas NTG eyes tended to have more severely depressed VF sensitivity at the superonasal quadrant and relatively preserved VF at the inferotemporal quadrant.

Metformin metabolic and vascular effects in normal weight hyperinsulinemic polycystic ovary syndrome patients treated with contraceptive vaginal ring. A pilot study

PURPOSE

The aim of this longitudinal, controlled, and retrospective pilot study was to assess how metformin, associated with a contraceptive vaginal ring, may influence lipid and carbohydrate metabolism, and surrogate markers of arterial function in normal weight polycystic ovary syndrome patients.

MATERIAL AND METHODS

Among 28 lean patients, 15 were treated with vaginal ring plus metformin and 13 women with only vaginal ring. The effects were assessed after six months. The patients were submitted to evaluation of lipid and carbohydrate metabolism; Doppler analysis of ophthalmic artery; brachial artery flow-mediated vasodilatation; and oral glucose tolerance test.

RESULTS

After six months, the fasting insulin, glucose/insulin ratio, and homeostatic model assessment estimates for insulin resistance were significantly improved in metformin group. The ophthalmic artery pulsatility index did not significantly improve in either group. The brachial artery vasodilation was better in metformin treated patients.

CONCLUSION

Metformin, associated with vaginal ring, improves the insulin and carbohydrate metabolism. This, associated with the significant improvements of surrogate markers of arterial function, may be responsible of a slight possible cardiovascular and cerebrovascular protective effect.

Girl Power in Glaucoma: The Role of Estrogen in Primary Open Angle Glaucoma

Estrogen is essential in maintaining various physiological features in women, and a decline in estrogen levels are known to give rise to numerous unfortunate symptoms associated with menopause. To alleviate these symptoms hormone replacement therapy with estrogen is often used, and has been shown to be fruitful in improving quality of life in women suffering from postmenopausal discomforts. An often forgotten condition associated with menopause is the optic nerve disorder, glaucoma. Thus, estrogen may also have an impact in maintaining the retinal ganglion cells (RGCs), which make up the optic nerve, thereby preventing glaucomatous neurodegeneration. This review aims to provide an overview of possible associations of estrogen and the glaucoma subtype, primary open-angle glaucoma (POAG), by evaluating the current literature through a PubMed-based literature search. Multiple in vitro and in vivo studies of RGC protection, as well as clinical and epidemiological data concerning the well-defined retinal neurodegenerative disorder POAG have been reviewed. Over all, deficiencies in retinal estrogen may potentially instigate RGC loss, visual disability, and eventual blindness. Estrogen replacement therapy may therefore be a beneficial future treatment. However, more studies are needed to confirm the relevance of estrogen in glaucoma prevention.

Metformin metabolic and vascular effects in overweight/moderately obese hyperinsulinemic PCOS patients treated with contraceptive vaginal ring: a pilot study

The aim of this pilot study was to assess how metformin, associated with a contraceptive vaginal ring, may influence lipid and carbohydrate metabolism, fat distribution, and surrogate markers of arterial function. Among 62 patients, 25 were treated with vaginal ring plus metformin and 37 women with only vaginal ring. The effects were assessed after 6 months. The patients were submitted to evaluation of lipid and carbohydrate metabolism; extended view ultrasonographic evaluation of fat distribution; Doppler analysis of ophthalmic artery; brachial artery flow-mediated vasodilatation; oral glucose tolerance test. After 6 months, the body mass index and waist/hip ratio resulted significantly better in patients who associated metformin to vaginal ring. The fasting glucose, insulin, and glucose/insulin ratio, HOMA-IR, glucose, and insulin AUC 120 were significantly improved in metformin group. The ultrasonographic fat analysis resulted significantly better after metformin. The ophthalmic artery PI significantly improved in metformin group. The brachial artery vasodilation was better in metformin treated patients. In conclusion, metformin, associated with vaginal ring, improves the insulin and carbohydrate metabolism, reduces the body weight and android fat distribution. This, associated with the significant improvements of surrogate markers of arterial function, may be responsible of possible cardiovascular and cerebrovascular protective effects.

The Relationship between Vitamin D and Glaucoma: A Kangbuk Samsung Health Study

PURPOSE

To investigate the relationship between vitamin D and glaucoma.

METHODS

This retrospective, cross-sectional study included subjects who underwent a health screening at the Health Screening Center of Kangbuk Samsung Hospital from August 2012 to July 2013. All fundus photographs were reviewed by ophthalmologists. The ophthalmologists determined if an eye was glaucomatous based on the criteria set forth by the International Society of Geographical and Epidemiological Ophthalmology and by the appearance of the retinal nerve fiber layer and optic disc. If the subjects previously underwent an ophthalmologic examination, they were enrolled based on the documented history. In addition to fundus photographs, each participant underwent a systemic examination including blood sampling and sociodemographic and behavioral questionnaires. The subjects were divided into five groups according to serum 25-hydroxyvitamin D (25(OH)D) level. Multivariate logistic regression models were constructed to assess possible associations between elevated glaucoma risk and systemic factors with a p < 0.2 on univariate analysis.

RESULTS

Of the 169,208 subjects older than 20 years, 123,331 were eligible for the study. There was no difference in the prevalence of glaucoma according to quintile of serum 25(OH)D level based on sex (p = 0.412 for males, p = 0.169 for females). According to the multivariable-adjusted logistic analysis, the odds ratio of glaucoma for the fourth quintile was significantly lower than that of the first quintile in females (odds ratio, 0.713; 95% confidence interval, 0.520 to 0.979).

CONCLUSIONS

Lower 25(OH)D level was significantly associated with an elevated risk of glaucoma in females compared with higher 25(OH)D level. Further evaluation is needed to investigate the relationship between glaucoma and vitamin D.

Relationship between progression of visual field defect and intraocular pressure in primary open-angle glaucoma

Purpose

To analyze the relationship between intraocular pressure (IOP) and the progression of visual field defects in Japanese primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) patients.

Patients and methods

The subjects of the study were patients undergoing treatment for POAG or NTG who had performed visual field tests at least ten times with a Humphrey field analyzer (Swedish interactive thresholding algorithm standard, C30-2 program). The progression of visual field defects was defined by a significantly negative value of the mean deviation slope at the final visual field test during the follow-up period. The relationships between the progression of visual field defects and IOP, as well as other clinical factors, were retrospectively analyzed.

Results

A total of 156 eyes of 156 patients were included in the analysis. Significant progression of visual field defects was observed in 70 eyes of 70 patients (44.9%), while no significant progression was evident in 86 eyes of 86 patients (55.1%). The eyes with visual field defect progression had significantly lower baseline IOP (P<0.05), as well as significantly lower IOP reduction rate (P<0.01). The standard deviation of IOP values during follow-up was significantly greater in the eyes with visual field defect progression than in eyes without (P<0.05).

Conclusion

Reducing IOP is thought to be useful for Japanese POAG or NTG patients to suppress the progression of visual field defects. In NTG, IOP management should take into account not only achieving the target IOP, but also minimizing the fluctuation of IOP during follow-up period.

[Effects of blood flow properties on ocular hemodynamics]

AIM

to study the effects of blood rheology on ocular blood flow (OBF) parameters and estimated individual normal range of intraocular pressure (IOP).

MATERIAL AND METHODS

A total of 15 patients (15 eyes) taking warfarin were enrolled. Volumetric parameters and linear velocity of OBF under warfarin treatment and after its cessation were obtained by means of flowmetry (Paradigm's Blood Flow Analyzer) and color Doppler flow mapping (Voluson 730), respectively. On the basis of flowmetry results an individual normal range of IOP was calculated in all patients.

RESULTS

Pulsatile OBF does not appear to correlate with warfarin-induced changes in blood rheology (p = 0.09), however, depends on IOP fluctuations (p = 0.02). Resistance index of retinal vessels is found to rise significantly with increasing blood viscosity (p < 0.05).

CONCLUSION

The use of warfarin, an indirect thrombin inhibitor, has no effect on estimated individual normal range of IOP, which is crucial for glaucoma diagnosis and monitoring.

Risk of glaucoma after early bilateral oophorectomy

OBJECTIVE

Because early estrogen deficiency may increase the susceptibility of the optic nerve to glaucoma, we studied the association of early bilateral oophorectomy with glaucoma.

METHODS

In the Mayo Clinic Cohort Study of Oophorectomy and Aging, we studied the risk of glaucoma by comparing women who underwent bilateral oophorectomy from 1950 to 1987 with age-matched referent women who did not undergo unilateral or bilateral oophorectomy. Glaucoma diagnostic codes were identified in the records linkage system of the Rochester Epidemiology Project. Hazard ratios (HRs) were calculated during a median follow-up of 25.5 years. Analyses were stratified by age at the time of bilateral oophorectomy (in tertiles).

RESULTS

Of 1,044 women who underwent bilateral oophorectomy before menopause, 147 developed glaucoma. Of 1,070 referent women, 133 developed glaucoma. Women who underwent bilateral oophorectomy showed no increased risk of glaucoma in the overall group (HR, 1.12; 95% CI, 0.89-1.42). However, women who underwent oophorectomy before the age of 43 years (n = 344; first tertile) had a significantly increased risk of glaucoma (HR, 1.60; 95% CI, 1.15-2.23). The results did not change after adjustment for hypertension, obesity, diabetes, or disorders of lipid metabolism at baseline. Approximately 11% of women who had undergone bilateral oophorectomy before the age of 43 years were treated with estrogen up to the age of 50 years; however, treatment did not reduce the association (HR, 1.59; 95% CI, 0.81-3.13).

CONCLUSIONS

Bilateral oophorectomy before the age of 43 years may increase the risk of glaucoma, and estrogen treatment does not seem to attenuate the risk.

Gender specific issues in hereditary ocular disorders

This review is intended to summarize the current knowledge from basic science and clinical medical literature cited within PubMed that pertain to gender-related factors and affect those individuals with hereditary ocular disorders. We consider gender-related biological factors that (a) affect disease onset and progression, (b) gender differences for major X-linked ocular disorders, (c) gender-specific conditions, (d) medications that may influence genetic eye disorders, and finally, (e) gender-related issues that influence the management and quality of life of these patients. Several studies have demonstrated the manner in which sex-related hormones in animal models are capable of influencing cell pathway and survival that are likely to affect hereditary eye disorders. There are very few clinical studies that provide compelling evidence for gender differences in human ocular conditions, other than for a number of X-linked disorders. Disease expression for X-linked disorders may be impacted by genetic mechanisms such as lyonization or uniparental disomy. Clinical evidence regarding the impact of gender-related medical conditions and therapies on eye conditions is extremely limited and primarily based on anecdotal evidence. Gender-specific factors may play a major role in the underlying biological pathways that influence the onset, rate of progression, and clinical findings associated with ocular genetic conditions. Clinicians need to be aware of the variable phenotypes observed in female carriers of X-linked disorders of gender specific issues, many of which are inadequately addressed in the current literature. Clinicians need to be sensitive to gender differences in social, cultural, and religious systems and they should also be aware of how their own gender biases may influence how they counsel patients. Finally, it is clear that the lack of effective clinical studies in this area creates an opportunity for future research that will have real benefits for these patients.

Is vitamin D status associated with open-angle glaucoma? A cross-sectional study from South Korea

OBJECTIVE

Open-angle glaucoma (OAG) is one of the major chronic diseases involving the optic nerve. However, little is known about the association between vitamin D and OAG. The present study was conducted to test the hypothesis that lower vitamin D status is associated with greater prevalence of OAG.

DESIGN

Cross-sectional study. Multivariable logistic regression was performed to examine the relationship between serum 25-hydroxyvitamin D (25(OH)D) and OAG after adjusting for traditional potential confounders. OAG was defined by the criteria of the International Society for Geographical and Epidemiological Ophthalmology.

SETTING

The Fifth Korean National Health and Nutrition Examination Survey conducted in 2010-2011.

SUBJECTS

Six thousand and ninety-four adult participants randomly selected from 192 surveys in 131 locations in South Korea.

RESULTS

Multivariable-adjusted odds ratios of OAG across quintiles of decreasing 25(OH)D were 1.26, 1.00 (reference), 1.31, 1.36 and 1.69 (P for quadratic trend <0.01). The odds ratio for the lowest 25(OH)D quintile was significantly higher than that for the second quintile (P < 0.01). In addition, we discovered that the predictors for worsening of OAG, such as intraocular pressure or vertical and horizontal cup-to-disc ratios, had a significant relationship with 25(OH)D level.

CONCLUSIONS

There was a reverse J-shaped association between 25(OH)D levels and the risk of OAG, with significantly elevated risk at lower 25(OH)D. The findings of this research suggest that vitamin D deficiency should be considered as a potential risk factor for the development of OAG. To our knowledge, the present study is the first one that shows an association between vitamin D status and OAG.

Estrogen deficiency accelerates aging of the optic nerve

The aim of this study was to provide a comprehensive review on hormone-based pathophysiology of aging of the optic nerve and glaucoma, including a literature review and expert opinions. Glaucoma, a group of intraocular pressure-related optic neuropathies, is characterized by the slow progressive neurodegeneration of retinal ganglion cells and their axons, resulting in irreversible visual sensitivity loss and blindness. Increasing evidence suggests that glaucoma represents the accelerated aging of the optic nerve and is a neurodegenerative disease of the central nervous system. This review highlights the high burden of glaucoma in older women and the importance of understanding the hormone-related pathophysiology of optic nerve aging and glaucoma in women. Strong epidemiological, clinical, and experimental evidence supports the proposed hypothesis that early loss of estrogen leads to premature aging and increased susceptibility of the optic nerve to glaucomatous damage. Future investigations into the hormone-related mechanisms of aging and glaucoma will support the development of novel sex-specific preventive and therapeutic strategies in glaucoma.

Moderate alcohol intake, genital vascularization, and sexuality in young, healthy, eumenorrheic women. A pilot study

INTRODUCTION

The relationship between alcohol and sexual function is complex and not completely understood.

AIM

To evaluate (in the early follicular phase and independently from sexual stimulation) in young, eumenorrheic, healthy, lean women the genital vascular effects of the light and moderate use of alcohol.

METHODS

Eighty-four women undertook, in the early follicular phase of the menstrual cycle (days 3-5), the administration of the two-factor Italian McCoy Female Sexuality (MFSQ) and the Beck Depression Inventory (BDI) questionnaires; ultrasonographic measurement of the carotid intima-media thickness (IMT); and color Doppler evaluation of the carotid, clitoral, and labia minora arteries. Hormonal (estradiol, androstenedione, and testosterone) and biochemical (lipids, glucose, and insulin) parameters were tested.

MAIN OUTCOME MEASURES

The MFSQ and BDI questionnaires; the carotid IMT; the Pulsatility Index of internal carotid, clitoral, and labia minora arteries; blood pressure measurement; and hormonal and biochemical assays.

RESULTS

The subjects were divided in: nondrinkers (group I); current (>1 year) light drinkers--1-10 drinks/month (group II); and current moderate drinkers--11-20 drinks/month (group III). The majority of the studied parameters did not vary among the different groups. The mean BDI was normal in the studied women. However, the lowest values were observed in the moderate drinkers group. The MFSQ did not show any difference among all the studied women. However, the number of intercourses/week and the incidence of vaginal orgasm were significantly higher in group III (moderate drinkers). The relationship between the drinking habits and different parameters showed an inverse relationship with the BDI. Furthermore, the BDI inversely correlated with orgasm frequency and with orgasm intensity.

CONCLUSIONS

Chronic slight/moderate alcohol consumption has no effects on genital vessels and vaginal lubrication. However, a moderate consumption of alcohol, through psychological and social disinhibiting effects, may favor sexual activities.

L-arginine plus drospirenone-ethinyl estradiol in the treatment of patients with PCOS: a prospective, placebo controlled, randomised, pilot study

OBJECTIVE

To verify the effects of a pill containing drospirenone on the surrogate markers of arterial function and to evaluate the possible improvements induced by the addition of L-arginine.

DESIGN

A prospective, placebo controlled, randomised, pilot study.

SETTING

University of Bologna.

POPULATION

Twenty-eight young women with PCOS.

METHODS

Random submission to: drospirenone + ethinylestradiol+ a placebo (Group I; n = 15) or drospirenone + ethinylestradiol + oral L-arginine (4 g × 2/daily) (Group II, n = 13).

MAIN OUTCOME MEASURES

Medical examination; blood measurement of nitrites/nitrates, biochemical and hormonal parameters; ultrasonographic analysis and colour Doppler evaluation of uterine, stromal ovarian and ophthalmic arteries; analysis of brachial artery flow-mediated vasodilatation; and 24-h ambulatory blood pressure monitoring. The above parameters were evaluated before and after 6 months.

RESULTS

The low dose oral contraceptive containing drospirenone favoured a pre-hypertensive state. The L-arginine supplementation increased the circulating levels of nitrites/nitrates and improved the endothelium-dependent vasodilatation counteracting the negative effect of the contraceptive pill.

CONCLUSIONS

Although, the present pilot study was conducted in a limited number of patients, it seems that the L-arginine co-treatment may improve the long-term side effects of the pill reducing the risk of cardiovascular diseases.

Gender and glaucoma: what we know and what we need to know

PURPOSE OF REVIEW

With growing aging populations and an increase in cases of glaucoma and glaucoma blindness worldwide, aging populations are particularly at higher risk of glaucoma and glaucoma blindness. Awareness of the gender differences might increase attention toward populations at risk.

RECENT FINDINGS

Women not only outlive men, but also outnumber men in glaucoma cases worldwide. Women are at higher risks for angle closure glaucoma, but there is no clear gender predilection for open angle glaucoma. Of interest, there is some evidence suggesting that female sex hormones might be protective of the optic nerve. In addition, it is hypothesized that decreased estrogen exposure is associated with increased risk for open angle glaucoma, yet population-based studies present inconsistent results. Presently, there is insufficient evidence to support hormonal replacement therapy use in glaucoma prevention. In addition, it appears that women carry a larger burden of glaucoma blindness due to longevity and disadvantages in socioeconomic/health beliefs.

SUMMARY

Current evidence suggests that older women are at risk for glaucoma and glaucoma blindness. Further interdisciplinary research involving investigators, specialized in glaucoma, women's health and health disparities, will lead to better understanding of gender health disparities in glaucoma and better targeting populations at risk.

Endothelial nitric oxide synthase gene variants and primary open-angle glaucoma: interactions with sex and postmenopausal hormone use

PURPOSE

To evaluate the association between the nitric oxide synthase gene (NOS3) variants and primary open-angle glaucoma (POAG).

METHODS

Two functional single-nucleotide polymorphisms (SNPs) (T-786C: rs2070744; Glu298Asp: rs1799983) and three tagging SNPs (rs7830, rs3918188, and rs1800779) were evaluated in a nested case-control study from the Nurses' Health Study (1980-2002) and the Health Professionals' Follow-up Study (1986-2002). Participants were aged >or=40 years and Caucasian. Included were 527 incident cases and 1543 controls, matched by cohort, age, and eye examination at the matched cases' diagnosis dates. Cohort-specific relative risks (RR) were estimated by using multivariable conditional logistic regression and were pooled with meta-analysis.

RESULTS

No NOS3 polymorphism was significantly associated with overall POAG. For high-tension POAG (HTPOAG), rs3918188 was significantly inversely associated among the women (AA versus CC genotype: RR = 0.48; 95% CI, 0.28-0.82) but not among the men (P-heterogeneity by sex = 0.02). The minor alleles of T -786C and rs1800779 showed positive association with high-tension POAG (P-trend < 0.02) in the women only, but P-heterogeneity was not significant. In the women, four of the five NOS3 SNPs showed significant interactions with postmenopausal hormone (PMH) use in relation to HTPOAG: for example, among the women with the TT genotype in T -786C, PMH use was inversely associated (RR = 0.41; 95% CI, 0.22-0.76), but among carriers of the minor allele, use of PMH was not associated.

CONCLUSIONS

Interactions were observed between NOS3 SNPs and female sex and postmenopausal hormone use in the women in relation to HTPOAG. These findings should be confirmed in different racial/ethnic groups.

Lifestyle, nutrition, and glaucoma

The only proven strategy to prevent primary open-angle glaucoma (POAG) is the use of ocular hypotensive therapy among people diagnosed with ocular hypertension. In this review, various modifiable lifestyle factors, such as exercise, diet, and cigarette smoking, that may influence intraocular pressure and that have been studied in relation to the risk of developing POAG are discussed. Epidemiologic studies on lifestyle factors are few, and the current evidence suggests that there are no environmental factors that are clearly associated with POAG; however, a few factors merit further study. This review also outlines future directions for research into the primary prevention of POAG.

The effects of raloxifene hydrochloride on ocular hemodynamics and visual function

OBJECTIVE

To assess the comprehensive effects of raloxifene hydrochloride on retinal, choroidal and retrobulbar hemodynamics and on visual function in post-menopausal women.

DESIGN

Twenty-four post-menopausal women (age 55 +/- 3.8 years) were recruited for this cross-sectional study: 12 received placebo and 12 received raloxifene hydrochloride 60 mg once a day for 3 months. Baseline measurements of both groups included heart rate (HR), blood pressure (BP), visual acuity, contrast sensitivity and intraocular pressure (IOP) for both eyes. A comprehensive ocular blood flow (OBF) assessment was obtained for each patient in a randomly chosen study eye. Retinal blood flow data was obtained using confocal scanning laser Doppler flowmetry [Heidelberg Retinal Flowmeter (HRF)]. Color Doppler imaging (CDI) was used to assess retrobulbar hemodynamics in the ophthalmic, central retinal, short nasal and temporal posterior ciliary arteries. Baseline vision and hemodynamics in post-menopausal subjects were compared using paired Student's t tests, and the percentage change in baseline versus 3-month parameters was analyzed.

RESULTS

There were no statistically significant differences between 3 months of raloxifene therapy and placebo in terms of age, HR, arterial or mean BP, visual acuity, contrast sensitivity, IOP or retinal or retrobulbar blood flow.

CONCLUSION

Raloxifene therapy at 60 mg/day had no clinically significant impact on BP, IOP or OBF in post-menopausal women.

Effect of Aerodiol administration on ocular arteries in postmenopausal women

OBJECTIVE

The aim of the present study was to evaluate the alteration of ocular blood hemodynamics after intranasal administration of 17beta-estradiol, through measurement of the ophthalmic artery (OA) and the central retinal artery (CRA) using color duplex sonography.

METHODS

Thirty healthy women who had been naturally postmenopausal for at least 1 year were enrolled in the study. A randomized, placebo-controlled, crossover, double-blinded study was conducted of the acute effect of 17beta-estradiol (Aerodiol; Servier, Chambrayles-Tours, France) on OA and CRA blood flow using color duplex sonography.

RESULTS

The peak systolic and end diastolic velocities of the CRA were increased significantly after 17beta-estradiol administration compared with placebo. A significant decrease was also found in the pulsatility and resistive indices of the CRA. However, there were no statistically significant differences in OA flow velocities or pulsatility and resistive indices.

CONCLUSIONS

Nasal 17beta-estradiol administration in postmenopausal women causes an improvement in the ocular vascular Doppler indices. These results suggest that there could be a positive effect of Aerodiol on middle-sized arteries and arterioles.

Retinal ganglion cell protection by 17-beta-estradiol in a mouse model of inherited glaucoma

Glaucoma is the second leading cause of blindness in the world. The ultimate cause of vision loss due to glaucoma is thought to be retinal ganglion cell (RGC) apoptosis. Neuroprotection of RGC is becoming an important approach of glaucoma therapy. Several lines of evidence suggest that estrogen has neurotrophic and neuroprotective properties. In this study, we examine the role of estrogen in preventing RGC loss in DBA/2J mouse, an in vivo model of an inherited (pigmentary) glaucoma. Two-month-old female DBA/2J mice were anesthetized and ovariectomized with or without subcutaneous 17beta-estradiol (betaE2) pellet implantation. RGC survival was evaluated from flat-mounted whole retinas by counting retrograde-labeled cells. The loss of nerve fibers and RGC were also evaluated in paraffin-fixed retinal cross sections. Biochemical alterations in the retinas of DBA/2J mice in response to systemic injection of betaE2 were also examined. We have made several important observations showing that: (1) betaE2 treatment reduced the loss of RGC and neurofibers through inhibition of ganglion cell apoptosis, (2) betaE2 activated Akt and cAMP-responsive-element-binding-protein (CREB), (3) betaE2 up-regulated thioredoxin-1 (Trx-1) expression, (4) betaE2 reduced the increased activations of mitogen-activated protein kinases (MAPK) and NF-kappaB, (5) betaE2 inhibited the increased interleukin-18 (IL-18) expression, and (6) treatment with tamoxifen, an estrogen receptor antagonist, blocked betaE2-mediated activation of Akt and inhibition of MAPK phosphorylation in the retinas of DBA/2J mice. These findings suggest the possible involvement of multiple biochemical events, including estrogen receptor/Akt/CREB/thioredoxin-1, and estrogen receptor/MAPK/NF-kappaB, in estrogen-mediated retinal ganglion cell protection.

Estrogen has a neuroprotective effect on axotomized RGCs through ERK signal transduction pathway

The neuroprotective effects of estrogen on neuronal cells in central nervous system have been described previously, however, the mechanisms of neuroprotective effect of estrogen against retinal ganglion cell (RGC) death has not been well identified. To examine the role of endogenous sex steroids produced in ovary, retina samples were prepared from female rats with or without ovariectomy and the density of RGC was calculated. Ovariectomy alone had no effect on the density of fluorogold (FG)-labeled RGC without injury, while the density of surviving RGC after optic nerve axotomy with ovariectomy was significantly decreased compared to that without ovariectomy. To examine the role of exogenous sex steroids, 17beta-estradiol was injected into the vitreous cavity in ovariectomized rats and showed neuroprotective effect on axotomy-induced RGC death while exogenous progesterone showed no effect. Immunoblot and immunohistochemical analysis demonstrated that ERK-c-Fos signal transduction pathway was activated by exogenous 17beta-estradiol in ganglion cell layer. U0126, an ERK inhibitor, inhibited the neuroprotective effect of estrogen on axotomized RGC death. These data suggest that estrogen has neuroprotective effect through activation of ERK-c-Fos signaling pathway on axotomy-induced RGC death. The neuroprotective effect of estrogen may have therapeutic benefits in retinal diseases associated with RGC death such as glaucoma.