Effect of long-term hormone replacement therapy on plasma homocysteine in postmenopausal women: a randomized controlled study

Prevalence and clinical correlates of hyperhomocysteinemia in Chinese urban population with hypertension

Context

The coexistence of hypertension and elevated homocysteine (Hcy) levels has a mutually reinforcing impact on the susceptibility to cardio-cerebrovascular disease.

Objective

The aim was to assess the prevalence, clinical correlation, and demographic characteristics of hyperhomocysteinemia (HHcy) within the Chinese urban population with hypertension.

Methods

A cohort of 473 individuals with hypertension were selected from four communities in Shenzhen, China. Demographic attributes, clinical profiles, and lifestyle behaviors were gathered and compared between individuals with and without HHcy. A logistic regression model was employed to examine potential factors associated with the prevalence of HHcy. Correlation between Hcy levels and clinical characteristics was assessed through multiple linear regression analysis.

Results

The prevalence of HHcy in the population with hypertension was 31.3%. In comparison to individuals without HHcy, those with HHcy exhibited a higher proportion of males, a higher prevalence of smoking and alcohol consumption, and a higher proportion of cases with the homozygous (TT) genotype at the MTHFR C677T polymorphism. Moreover, individuals with HHcy had lower levels of folic acid (FA), and lower fruit and vitamin B12 intake. Furthermore, the risk factors for HHcy were male (B = 1.430, OR = 4.179) and MTHFR (TT) (B = 1.086, OR = 2.961). In addition, the multiple linear regression analysis revealed a significant association between Hcy levels and gender (B = -2.784, P = 0.004), MTHFR genotypes (B = 1.410, P = 0.005), and FA levels (B = -0.136, P = 0.030).

Conclusion

The high prevalence of HHcy among hypertensive patients in this Chinese urban population underscores the necessity for interventions targeting modifiable risk factors such as dietary choices and lifestyle practices.

Onset and Recurrence Characteristics of Chinese Patients with Noncardiogenic Ischemic Stroke in Chinese Medicine Hospital

OBJECTIVE

To delineate the onset and recurrence characteristics of noncardiogenic ischemic stroke patients in China.

METHODS

A prospective, multicenter and registry study was carried out in 2,558 patients at 7 representative clinical sub-centers during November 3, 2016 to February 17, 2019. A questionnaire was used to collect information of patients regarding CM syndromes and constitutions and associated risk factors. Additionally, stroke recurrence was defined as a primary outcome indicator.

RESULTS

A total of 327 (12.78 %) patients endured recurrence events, 1,681 (65.72%) were men, and the average age was 63.33 ± 9.45 years. Totally 1,741 (68.06%) patients suffered first-ever ischemic stroke, 1,772 (69.27%) patients reported to have hypertension, and 1,640 (64.11%) of them reported dyslipidemia, 1,595 (62.35%) patients exhibited small-artery occlusion by The Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Specifically, 1,271 (49.69%) patients were considered as qi-deficient constitution, and 1,227 (47.97%) patients were determined as stagnant blood constitution. There were 1,303 (50.94%) patients diagnosed as blood stasis syndrome, 1,280 (50.04%) patients exhibited phlegm and dampness syndrome and 1,012 (39.56%) patients demonstrated qi deficiency syndrome. And 1,033 (40.38%) patients declared intracranial artery stenosis, and 478 (18.69%) patients reported carotid artery stenosis. The plaque in 1,508 (41.36%) patients were of mixed. Particularly, 41.09% of them demonstrated abnormal levels of glycated hemoglobin levels.

CONCLUSIONS

Recurrence in minor and small-artery stroke cannot be ignored. Hypertension, dyslipidemia, abnormal HbA1c, intracranial artery stenosis and carotid plaque were more common in stroke patients. Particularly, phlegm-dampness and blood stasis syndromes, as well as qi deficiency and blood stasis constitutions, were still the main manifestations of stroke. (Trial registration at ClinicalTrials.gov No. NCT03174535).

Does genistein lower plasma lipids and homocysteine levels in postmenopausal women? A meta-analysis

OBJECTIVE

To perform a meta-analysis examining the effects of genistein on homocysteine and lipid levels in postmenopausal women.

METHODS

We systematically searched the PubMed, MEDLINE, and Cochrane Library databases and the ClinicalTrials.gov website for studies. We performed a meta-analysis using weighted mean differences (WMD) and 95% confidence intervals in a random-effects model. We assessed between-study heterogeneity using the Cochran's Q and I(2) statistics.

RESULTS

Eight randomized, controlled trials with a total of 476 subjects were included in the meta-analysis. Compared with placebos, genistein was effective in reducing plasma levels of homocysteine (WMD, -0.58 μmol/l; p = 0.001), and increasing high density lipoprotein (HDL) cholesterol levels (WMD, 4.9 mg/dl; p = 0.0002). Subgroup analyses revealed that genistein significantly decreased the levels of low density lipoprotein (LDL) cholesterol (WMD, -16.90 mg/dl; p = 0.01), total cholesterol (WMD, -15.83 mg/dl; p = 0.008), and triglycerides (WMD, -46.58 mg/dl; p = 0.03) in postmenopausal women with metabolic syndrome, but had no significant effects in those with no metabolic syndrome.

CONCLUSIONS

Our meta-analysis demonstrates that genistein significantly reduces homocysteine levels and increases HDL cholesterol levels in postmenopausal women. Genistein also significantly decreases LDL cholesterol, total cholesterol and triglyceride levels in postmenopausal women with metabolic syndrome.

Gender differences in the risk factors for endothelial dysfunction in Chinese hypertensive patients: homocysteine is an independent risk factor in females

Objectives

Endothelial dysfunction plays a key role in the pathogenesis of cardiovascular disease. However, the gender-related differences in risk factors for endothelial dysfunction are controversial. We investigated the gender differences in the risk factor profiles for endothelial dysfunction in Chinese hypertensive patients.

Methods

Vascular endothelial functions in 213 hypertensive patients were measured by digital reactive hyperemia peripheral arterial tonometry (RH-PAT). Peripheral blood samples were collected, and the self-reported smoking and alcohol consumption status, age, body mass index, heart rate, blood pressure and drug administrations were recorded.

Results

RH-PAT indexes were attenuated in both male and female hypertensive patients [1.60 (1.38-2.02) vs. 1.63 (1.44-1.98)]. Multivariate logistic regression analysis identified plasma creatinine (p < 0.001), total cholesterol (p = 0.001), homocysteine (p = 0.002) and smoking (p < 0.001) as the independent factors correlated with gender (male). Multivariate linear regression analysis further identified homocysteine as the factor that is significantly and independently correlated with the decrease in the RH-PAT indexes in female patients (odds ratio: -0.166, 95% confidence interval: -0.292 to -0.040, p = 0.01). However, none of these four factors were correlated with the RH-PAT indexes in male patients.

Conclusions

There are gender-related differences in the risk factors for endothelial dysfunction in Chinese hypertensive patients. Homocysteine is an independent factor for endothelial dysfunction in female hypertensive patients.

What is the influence of hormone therapy on homocysteine and crp levels in postmenopausal women?

OBJECTIVE

To evaluate the influence of estrogen therapy and estrogen-progestin therapy on homocysteine and C-reactive protein levels in postmenopausal women.

METHODS

In total, 99 postmenopausal women were included in this double-blind, randomized clinical trial and divided into three groups: Group A used estrogen therapy alone (2.0 mg of 17β-estradiol), Group B received estrogen-progestin therapy (2.0 mg of 17 β-estradiol +1.0 mg of norethisterone acetate) and Group C received a placebo (control). The length of treatment was six months. Serum measurements of homocysteine and C-reactive protein were carried out prior to the onset of treatment and following six months of therapy.

RESULTS

After six months of treatment, there was a 20.7% reduction in homocysteine levels and a 100.5% increase in C-reactive protein levels in the group of women who used estrogen therapy. With respect to the estrogen-progestin group, there was a 12.2% decrease in homocysteine levels and a 93.5% increase in C-reactive protein levels.

CONCLUSION

Our data suggested that hormone therapy (unopposed estrogen or estrogen associated with progestin) may have a positive influence on decreasing cardiovascular risk due to a significant reduction in homocysteine levels.

MTHFR C677T polymorphism modifies the effect of HRT on metabolic parameters in postmenopausal women

OBJECTIVE

To assess the interaction of the MTHFR C677T polymorphism with changes in lipid and glucose metabolism effected by oral hormone replacement therapy (HRT) in postmenopausal women.

METHODS

In this open-label, prospective, interventional study, parameters of lipid and glucose metabolism, as well as homocysteine, were assessed in 97 postmenopausal women at baseline and 1 year after the initiation of HRT. Participants were stratified into three subgroups, according to the MTHFR C677T polymorphism (wild-type: CC genotype; heterozygous: CT genotype; homozygous for the mutant variable: TT genotype).

RESULTS

The TT genotype was associated with an elevation of total and low density lipoprotein (LDL) cholesterol, while CT and CC genotypes were associated with a reduction of total cholesterol and LDL cholesterol after 1 year of HRT (p = 0.032 for total cholesterol and p = 0.002 for LDL cholesterol). Women with the TT genotype had higher glucose levels in contrast to women with the CC genotype who had lower glucose levels after 1 year of HRT (p = 0.011). Additionally, CC carriers under HRT had a significant elevation of apolipoprotein A1 levels (p = 0.018), contrarily to CT and TT genotypes.

CONCLUSION

While HRT was associated with favorable changes in lipid and metabolic parameters in carriers of the CC genotype, this effect was not evident in carriers of the T allele. The MTHFR C677T polymorphism may modify the effect of HRT on lipid and metabolic parameters in postmenopausal women.

Hormone replacement therapy: relation to homocysteine and prooxidant-antioxidant status in healthy postmenopausal women

OBJECTIVES

Studies have consistently shown a lower cardiovascular risk in women who received postmenopausal hormone replacement therapy (HRT).

DESIGN AND METHODS

In this study, the effects of HRT were investigated on plasma total homocysteine (tHcy) and the oxidant-antioxidant status in postmenopausal women. 35 of postmenopausal receiving (2 mg estrodiol valerate + 1 mg cyproterone acetate) HRT group, the remaining 25 received orally placebo (NHRT group).

RESULTS

There was no significant change in plasma tHcy levels between HRT and NHRT groups. Malondialdehyde (MDA) and total thiol (t-SH) correlated significantly with tHcy (0.388 and 0.478, respectively) content, and there was a significant negative correlation between E2 level and glutathione transferase (GST) activity (-0.425) in HRT group. Superoxide dismutase (SOD) and HDL-C correlated significantly with t-SH level (0.339 and 0.336, respectively) in plasma after HRT.

CONCLUSION

Our results show that HRT is beneficial in the protection against oxidative damage, and prevents atherosclerotic complications.

Serum homocysteine and asymmetric dimethylarginine levels in patients with premature ovarian failure: a prospective controlled study

OBJECTIVE

To investigate serum homocysteine and asymmetric dimethylarginine (ADMA) levels in patients with premature ovarian failure (POF).

STUDY DESIGN

A total of 69 women, 32 with POF and 37 apparently healthy women were included in the study. Fasting blood samples were drawn to measure serum homocysteine and ADMA levels using ELISA method.

RESULTS

The study and control group had a mean age of 37.3 + 2.6, 37.5 + 2.5 years; a mean homocysteine level of 13.54 + 5.19, 12.71 + 3.99 mmol/l and a mean ADMA level of 1.32 + 0.27, 1.26 + 0.36 mmol/l, respectively. There were no statistically significant differences between the two groups in terms of homocysteine and ADMA levels (with p values of 0.465 and 0.423, respectively). A negative significant correlation was found between estradiol and ADMA (p <0.05).

CONCLUSION

Homocysteine and ADMA levels did not change in comparison with the control group, which suggests that estrogen deficiency in patients with POF does not have any effect on homocysteine and asymmetric dimethylarginine levels.

Intraindividual variability of homocysteine and related thiols concentrations in follicular fluid

PURPOSE

To determine intraindividual variability in concentrations of homocysteine and related thiols in follicular fluids of particular follicles after ovarian stimulation and assess the differences between follicles with/or without oocytes.

METHODS

HPLC-FD analysis of plasma and follicular fluid cysteine, homocysteine, cysteinylglycine and glutathione in women undergoing IVF.

RESULTS

In blood plasma, the homocysteine, cysteine, and cysteinylglycine concentrations decreased significantly during stimulation with rec FSH (p<0.001). We found significant differences in concentrations of cysteine and glutathione between follicles with or without retrieved oocytes. High intraindividual variability in concentrations of thiols was determined.

CONCLUSIONS

The concentration variability of thiols between single follicles is very high and we recommend mean at least from 3 follicles with/or without oocytes for characterization of each woman. It is the best to examine individual follicles for further research and analysis of fertility outcomes.

Thrombophilia and the risk of thromboembolic events in women on oral contraceptives and hormone replacement therapy

Thrombophilia contributes to the risk of thrombosis in women using female hormones. The objective of the present study was to evaluate the prevalence of thrombophilia in women with thromboembolic events (TEEs) using oral contraceptives or hormone replacement therapy (HRT) and assess the contribution of a family history and the duration of hormone use in predicting thrombosis. A retrospective analysis was performed of the case records of women who developed a TEE while on oral contraceptives or HRT and were referred for thrombophilia evaluation over a 4-year period. Among 85 women who developed a TEE while on oral contraceptives or HRT, 65 had at least one additional thrombophilia risk factor. Of the 85 cases, 23 tested positive for more than two thrombophilias, 16 had factor V Leiden, five had the prothrombin gene G20210A polymorphism, 26 had antiphospholipid antibodies, 10 had elevated homocysteine, four had protein C deficiency, and seven had protein S deficiency. There were 64 TEE: 16 pulmonary emboli, 17 cerebrovascular events, 11 intra-abdominal thromboses, 13 deep venous thromboses, five cases of superficial thrombophlebitis, and two retinal vein thromboses. Of the 65 women, 37% had a positive family history of thrombosis. Approximately half of the women had been taking oral contraceptives or HRT for more than 1 year. There is a high prevalence of thrombophilia in women who developed a TEE while using oral contraceptives or HRT for more than 1 year. Family and personal history of thrombosis should be carefully evaluated in all women before initiating or continuing oral contraceptives or HRT, and a positive history may warrant a thrombophilia screening.

Homocysteine in pregnancy

The aim of this review is to evaluate the evidence for and against fasting plasma total homocysteine (tHcy) as a biomarker/risk factor of impaired reproductive function before and during pregnancy. Apart from nutritional and lifestyle factors, tHcy is also influenced by physiological factors specific to pregnancy such as hemodilution, increased glomerular filtration rate, and endocrinological changes. These lead to a considerable reduction under normal circumstances in tHcy by midpregnancy. Stimulating excess endogenous homocysteine production before and during pregnancy in animal experiments and adding exogenous homocysteine to cell cultures result in the impairment of reproductive and developmental processes from preconception throughout pregnancy and during subsequent development of the offspring. Different studies have confirmed that elevated tHcy is a risk factor for subfertility, congenital developmental defects, preeclampsia, and intrauterine growth retardation. There is conflicting evidence that elevated tHcy is a risk factor for miscarriage, gestational diabetes, premature rupture of the membranes, placental abruption, and offspring with Down syndrome. Prospective, sufficiently powered, studies from preconception/early pregnancy are required to determine whether tHcy is a risk factor for these pregnancy complications.

Homocysteine: biomarker or cause of adverse pregnancy outcome?

Total fasting plasma homocysteine (tHcy) is significantly reduced during early-mid normal pregnancy. Elevated tHcy during or outside of pregnancy has been associated with adverse pregnancy outcomes, affecting either the fetus or the evolution of the pregnancy. Examples of direct adverse effects on the fetus are neural tube defects, Down's syndrome, congenital heart defects and intrauterine growth retardation. Both fetal and maternal wellbeing can be affected by other adverse outcomes reported to be associated with elevated tHcy, such as recurrent spontaneous abortion, pre-eclampsia or placental vasculopathy. To date, endothelial activation of the placental vascularization system, apoptosis, toxicity and stimulation of uterine contractions have been proposed as possible modes of adverse action of homocysteine. The strength of the clinical evidence for a pathological role of elevated homocysteine in the evolution of pregnancy is examined in this review.

Efficacy of genistein aglycone on some cardiovascular risk factors and homocysteine levels: A follow-up study

BACKGROUND AND AIM

Recent evidence suggests that genistein aglycone may act beneficially on surrogate cardiovascular risk markers in postmenopausal women. We assessed the effects of genistein aglycone on some cardiovascular risk factors and homocysteine levels after 3-years of continued therapy in a cohort of osteopenic, postmenopausal women.

METHODS AND RESULTS

The parent study was a randomized, double-blind, placebo-controlled trial involving 389 postmenopausal women with low bone mass for 24 months. Subsequently, a subcohort (138 patients) continued therapy for an additional year. Participants received 54mg of genistein aglycone (n=71) or placebo (n=67), daily. Both arms received calcium and vitamin D(3) in therapeutic doses. Moreover, 4 weeks before randomization procedures and during our follow-up study, all patients received dietary instructions in an isocaloric fat-restricted diet. Blood lipid profiles, fasting glucose and insulin, insulin resistance (HOMA-IR), fibrinogen, osteoprotegerin (OPG) and homocysteine at baseline and after 24 and 36 months of treatment were measured. Compared to placebo, genistein significantly decreased fasting glucose and insulin, HOMA-IR, fibrinogen and homocysteine after 24 and 36 months of treatment. By contrast, isoflavone administration did not affect high-density lipoprotein cholesterol and triglycerides though serum OPG was higher in the genistein recipients. There were no differences in adverse events or discomfort between groups. Results on routine biochemical, liver function, and hematologic testing did not change over time in placebo or genistein group.

CONCLUSIONS

After 3-years of treatment, genistein aglycone plus calcium, vitamin D(3) and a healthy diet showed positive effects on some cardiovascular risk factors and homocysteine levels in a cohort of postmenopausal women with low bone mass.

Serum C-reactive protein and plasma homocysteine levels are associated with hormone therapy use and other factors: a population-based study of middle-aged Australian-born women

OBJECTIVE

To investigate the associations between C-reactive protein (CRP), homocysteine levels, use of hormone therapy (HT) and other factors.

METHODS

A 12-year prospective study of 438 Australian-born women (Melbourne Women's Midlife Health Project), who at baseline were aged 45-55 years, had menstruated in the previous 3 months and were not taking HT. Fasting blood was collected in the 11th follow-up year for CRP, homocysteine, estradiol and follicle stimulating hormone (FSH) levels. Physical measurements and face-to-face interviews obtained information on health and lifestyle variables.

RESULTS

A total of 258 women (mean age 60 years) participated in the 11th follow-up year. Multiple regression analysis found that CRP levels were positively associated with body mass index (p < 0.001), HT use (p < 0.01), and negatively associated with statin use (p < 0.005) and exercising (p < 0.05). In postmenopausal women currently not using HT (n = 173) and after adjusting for body mass index, exercise and smoking, CRP was negatively associated with FSH levels (beta = -0.32, p < 0.05). Homocysteine levels were positively associated with smoking (p < 0.001) and negatively associated with HT use (p < 0.05).

CONCLUSION

In middle-aged Australian-born women, HT use was associated with increased CRP and decreased homocysteine levels. High CRP levels were also associated with high relative weight, low exercise levels and no statin medication.

The effect of short-term estradiol therapy on clotting and inflammatory markers in older men receiving hormonal suppression therapy for prostate cancer

The cardio protective effect of estrogen in women has come under scrutiny as recent evidence from long-term trials has demonstrated negative findings. In contrast, the effect of endogenous sex hormones, specifically estrogen, on cardiovascular disease, inflammation and clotting parameters in men has not been well-studied. Men receiving androgen deprivation therapy for prostate cancer provide a unique model to study the effect of estrogen alone on inflammation and clotting factors. In a short-term randomized controlled trial of 17-beta estradiol (E(2)) versus placebo, we measured sex hormones, markers of inflammation including homocysteine (HC), C-reactive protein (CRP), interleukin-6 (IL-6) and coagulation factors including fibrinogen, plasminogen activator-inhibitor-1 (PAI-1) and anti-thrombin-III (AT-III) in 27 older men without bone metastases receiving androgen deprivation therapy or neoadjuvant treatment for prostate cancer. After 9 weeks of E(2) treatment, there was no difference in inflammation or clotting parameters between groups, but after 9 weeks of treatment AT-III increased in the E(2) treated group and decreased in the placebo group. CRP, homocysteine and IL-6 did not show any significant differences. We also evaluated the above parameters in 12 men 3 weeks after acute steroid withdrawal with androgen deprivation therapy and found no significant changes. We found an increase in AT-III in men receiving E(2) which may be related to gonadal steroid withdrawal, but no significant differences in other inflammatory or clotting factor parameters. While the current report is very preliminary in a small group of subjects, further studies are needed to determine the long-term effects of E(2) in this population of hypogonadal men.

Effects of estrogen and estrogen-progestogen therapy on homocysteine levels and their correlation with carotid vascular resistance

OBJECTIVE

To evaluate the correlation between homocysteine levels and carotid vascular resistance in menopausal women submitted to estrogen and estrogen-progestogen therapy.

METHODS

Eighty-six women with a mean age of 52 years were enrolled in a prospective, randomized, double-blind, 6-month study. Patients were allocated to use one of three oral therapies: placebo (n = 26), micronized estradiol 2 mg/day (n = 30) or micronized estradiol 2 mg/day plus norethisterone acetate 1 mg/day (n = 30). Evaluation of homocysteine levels and Doppler sonography of the common carotid artery, used to calculate pulsatility index (PI), were carried out prior to initiating therapy and at the end of the study. The correlation between these two parameters was evaluated using Pearson's coefficient of correlation.

RESULTS

There was a significant reduction in homocysteine levels in the groups treated with estrogen alone or estrogen combined with norethisterone. PI was significantly lower only in users of estrogen alone; however, no significant correlation was found between homocysteine measurements and PI.

CONCLUSION

No significant correlation was found between homocysteine levels and carotid vascular resistance following hormone therapy.

A comparison of the effects of sequential transdermal versus continuous orally administered hormone replacement therapies on plasma total homocysteine levels in postmenopausal women: A randomized, placebo-controlled study

OBJECTIVE

The objective was to determine the effects of transdermal and oral hormone replacement therapies on plasma total homocysteine levels in postmenopausal women.

MATERIAL AND METHODS

One hundred and ten postmenopausal patients were enrolled in the study. Participants were randomized into three groups: in Group A (n = 31) oral continuous combined therapy and in Group B (n = 30) transdermal sequential hormone replacement therapy were given for 6 months. A placebo was administered orally to the control group (Group C, n = 30). Serum homocysteine levels were studied prior to and after 6 months of treatment in all groups.

RESULTS

There were no statistical significant differences in mean serum homocysteine levels among the groups prior to the study. The mean homocysteine levels after 6 months in Groups A-C were also similar.

CONCLUSIONS

Serum homocysteine levels alter with neither oral continuous nor sequential transdermal hormone replacement therapy.

Sleep disturbances, oxidative stress and cardiovascular risk parameters in postmenopausal women complaining of insomnia

OBJECTIVE

The aim of this work was to investigate cardiovascular risk factors and oxidative stress parameters as well as sleep disturbances in polysomnography recordings of 38 postmenopausal women with insomnia.

METHODS

Polysomnography recordings were performed on subjects for sleep analysis. Oxidative stress parameters were analyzed by measuring blood concentration of catalase, superoxide dismutase (SOD), thiobarbituric acid reactive substances (TBARS) and glutathione. For cardiovascular risk factors, we measured plasma levels of homocysteine, folic acid and vitamin B6.

RESULTS

Findings of polysomnography recordings revealed: 68% experienced decreased sleep efficiency, 50% had apnea, 7.8% had periodic leg movements and 2.6% had bruxism (involuntary gnashing and grinding of the teeth during sleep). Our results showed that the majority of our subjects presented normal concentrations of the parameters studied according to standards reached in our laboratory. The only notable exception was TBARS. In this case, only 21% displayed normal values. We also found inverse correlations between SOD activity and both age and time of menopause.

CONCLUSIONS

Although all women complained of insomnia, 50% of them demonstrated apnea during polysomnography recordings. Of the parameters measuring oxidative stress, only TBARS levels were increased in our sample. Some clinical data, such as time of onset of menopause, may be associated with the oxidative stress status of these women, probably due to the lack of estrogen and to sleep disturbances, such as apnea.

Effect of oral conjugated equine estrogen combined with medroxyprogesterone acetate on plasma homocysteine levels in postmenopausal women

Conjugated equine estrogen alone or combined with medroxyprogesterone acetate lowered homocysteine levels in postmenopausal women. Regardless of the dosage of progestin used, there was no impact on homocysteine metabolism after 3 years of therapy.

Association of the C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene with schizophrenia: association is significant in men but not in women

Schizophrenia is a complex and common psychiatric disorder with a polygenic inheritance. In our previous report, we showed an association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms and schizophrenia in patients from Bakirkoy in Istanbul, Turkey [Sazci, A., Ergul, E., Guzelhan, Y., Kaya, G., Kara, I., 2003. Methylenetetrahydrofolate reductase gene polymorphisms in patients with schizophrenia. Mol. Brain Res. 117, 104-107]. We wanted also independently to confirm this study in a gender-specific manner with schizophrenic patients from Erenkoy in Istanbul, Turkey. To investigate the role of the C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene in schizophrenia in a gender-specific manner, we analyzed the genotypes of MTHFR677 and MTHFR1298 of 297 schizophrenic patients and 341 healthy controls, using a polymerase chain reaction restriction fragment length polymorphism method. The MTHFR 677T allele was significantly distributed (chi2=7.312; P=0.026), between schizophrenic patients and healthy controls. The T677T genotype was overrepresented in the total schizophrenic patients (OR=1.938; 95%CI=1.133-3.315; chi2=5.996; P=0.014). Similarly, the T677T/A1298A compound genotype was the most significant one in the total schizophrenic patients (OR=2.397; 95% CI=1.327-4.330; chi2=8.821; P=0.003). The C1298C genotype was overrepresented in the total schizophrenic patients (OR=1.706; 95%CI=1.014-2.870; chi2=4.126; P=0.042). Likewise, the C677C/C1298C compound genotype was significant in the total schizophrenic patients (OR=1.689; 95%CI=0.985-2.894; chi2=3.695; P=0.055). When schizophrenic patients and healthy controls were stratified according to gender difference, the T677T genotype and T677T/A1298A compound genotype were significantly overrepresented (OR=2.184; 95% CI=1.069-4.462; chi2=4.767; P=0.029; OR=2.748; 95% CI=1.215-6.214; chi2=6.301; P=0.012, respectively) in men schizophrenic patients. However, neither the MTHFR C677T nor the A1298C polymorphisms are associated with schizophrenia in women. In conclusion, the MTHFR 677T allele and T677T, C1298C genotypes, and T677T/A1298A, C677C/C1298C compound genotypes are genetic risk factors for schizophrenia in men but not in women in a gender-specific manner.

Homocysteine and vitamin B12 status relate to bone turnover markers, broadband ultrasound attenuation, and fractures in healthy elderly people

Hyperhomocysteinemia may contribute to the development of osteoporosis. The relationship of Hcy and vitamin B12 with bone turnover markers, BUA, and fracture incidence was studied in 1267 subjects of the Longitudinal Aging Study Amsterdam. High Hcy and low vitamin B12 concentrations were significantly associated with low BUA, high markers of bone turnover, and increased fracture risk.

INTRODUCTION

Hyperhomocysteinemia may contribute to the development of osteoporosis. Vitamin B12 is closely correlated to homocysteine (Hcy). The main objective of our study was to examine the association of Hcy and vitamin B12 status and the combined effect of these two with broadband ultrasound attenuation (BUA), bone turnover markers, and fracture.

MATERIALS AND METHODS

Subjects were 615 men and 652 women with a mean age of 76 +/- 6.6 (SD) years of the Longitudinal Aging Study Amsterdam (LASA). At baseline (1995/1996), blood samples were taken after an overnight fast for dairy products. Plasma Hcy was measured with IMx, serum vitamin B12 with competitive immunoassay (IA) luminescence, serum osteocalcin (OC) with immunoradiometric assay (IRMA), and urinary excretion of deoxypyridinoline (DPD) with competitive IA and corrected for creatinine (Cr) concentration. CVs were 4%, 5%, 8%, and 5%, respectively. BUA was assessed in the heel bone twice in both the right and left calcaneus. Mean BUA value was calculated from these four measurements. CV was 3.4%. After baseline measurements in 1995, a 3-year prospective follow-up of fractures was carried out until 1998/1999. Subjects were grouped by using two different approaches on the basis of their vitamin B12 concentration, normal versus low (<200 pM) or lowest quartile (Q1) versus normal quartiles (Q2-Q4), and Hcy concentration, normal versus high (>15 microM) or highest quartile (Q4) versus normal quartiles (Q1-Q3). Analysis of covariance was performed to calculate mean values of BUA, OC, and DPD/Cr(urine) based on the specified categories of Hcy and vitamin B12 and adjusted for several confounders (potential confounders were age, sex, body weight, body height, current smoking [yes/no], mobility, cognition). The relative risk (RR) of any fracture was assessed with Cox regression analysis. Quartiles were used when Hcy and vitamin B12 were separately studied in their relationship with fracture incidence.

RESULTS

Fourteen percent of the men and 9% of the women had high Hcy (>15 microM) and low vitamin B12 (<200 pM) concentrations. Women with vitamin B12 levels <200 pM and Hcy concentrations >15 microM had lower BUA, higher DPD/Cr, and higher OC concentrations than their counterparts. In men, no differences were found between the different Hcy and vitamin B12 categories in adjusted means of BUA, OC, or DPD/Cr(urine). Twenty-eight men and 43 women sustained a fracture during the 3-year follow-up period. The adjusted RR for fractures (95% CI) for men with high Hcy and/or low vitamin B12 concentrations was 3.8 (1.2-11.6) compared with men with normal Hcy and vitamin B12 concentrations. Women with high Hcy and/or low vitamin B12 concentrations had an adjusted RR for fractures of 2.8 (1.3-5.7).

CONCLUSIONS

High Hcy and low vitamin B12 concentrations were significantly associated with low BUA, high markers of bone turnover, and increased fracture risk.

Effects of two continuous hormone therapy regimens on C-reactive protein and homocysteine

OBJECTIVE

To compare the effects of two continuous hormone therapy (HT) regimens on the cardiovascular risk markers, C-reactive protein (CRP) and homocysteine.

DESIGN

A prospective study in which 43 postmenopausal women were randomly assigned to either tibolone 2.5 mg/day (n = 20) or 0.625 mg/day conjugated equine estrogens (CEE) plus continuous medroxyprogesterone acetate (MPA) 5 mg/day (n = 23). Serum levels of CRP, homocysteine, vitamin B12, and folate were determined before and during 12 weeks of therapy.

RESULTS

C-reactive protein levels were increased by tibolone (76%; P < 0.001) and CEE+MPA (81%; P < 0.001). Neither tibolone nor CEE+MPA had any significant effect on homocysteine levels, but there was a significant difference between the effects of treatment over time (P = 0.046). Both tibolone and CEE+MPA reduced vitamin B12 levels (11%; P < 0.001, and 8%; P < 0.01, respectively), but had no statistically significant effect on folate levels. Individual changes in homocysteine levels were negatively associated with changes in vitamin B12 levels (r = -0.68; P < 0.01) after tibolone therapy.

CONCLUSION

Both tibolone and CEE plus MPA increased CRP levels and reduced levels of vitamin B12. Neither therapy had any significant effect on homocysteine levels. Further long-term studies into the effect of HRT on these markers, and the relationship to cardiovascular disease risk, are required.

Effects of traditional Chinese medicines on serum lipid profiles and homocysteine in the ovariectomized rats

To investigate the effects of the traditional Chinese medicines, kuei-lu-erh-hsien-chiao and chia-wei-hsiao-yao-san, on the cardiovascular systems of mimic menopausal rats, five groups were formed: group 1 (the control group) was given a sham operation and received distilled water, while groups 2, 3, 4 and 5 were ovariectomized and received distilled water, kuei-lu-erh-hsien-chiao, chia-wei-hsiao-yao-san and 17-beta-estradiol, respectively, for4 months. Our results demonstrated that the mean differences of the estrogen levels in groups 3 or 5 were significantly higher than those of group 2. These data suggest that there might be some estrogen-like substances in kuei-lu-erh-hsien-chiao. However, the function of these estrogen-like substances was unknown. The mean differences of the triglyceride (TG) levels, high-density lipoprotein cholesterol (HDL-C) levels, low-density lipoprotein cholesterol (LDL-C) levels, and the ratios of TC/HDL-C and LDL-C/HDL-C in groups 1, 3, 4 and 5 were not significantly different from those in group 2. The mean differences of the total cholesterol (TC) levels in group 5 were significantly higher than those in group 2 (p < 0.05), but no obvious difference of the TC levels was found between groups 2 and 4. Nevertheless, the mean differences of the homocysteine (Hcy) levels in groups 4 and 5 were statistically lower than those of group 2. Therefore, administration of chia-wei-hsiao-yao-san declines the Hcy levels in OVX rats and does not affect the TC levels in these animals. In conclusion, our results indicate that chia-wei-hsiao-yao-san shows a more profound effect than 17-beta-estradiol in the prevention of atherosclerosis in these OVX rats.

The effect of the phytoestrogen genistein and hormone replacement therapy on homocysteine and C-reactive protein level in postmenopausal women

BACKGROUND

The aim of the study was to evaluate the effect, in postmenopausal women, of the phytoestrogen genistein and hormone replacement therapy (HRT) on circulating two independent factors of cardiovascular risk: homocysteine and C-reactive protein (CRP).

METHODS

Ninety healthy postmenopausal women, from 50 to 60 years of age, were randomly assigned to receive genistein (n = 30; 54 mg/die) or continuous combined estrogen/progestin therapy (17-beta-estradiol 1 mg plus norethisterone acetate 0.5 mg) or placebo. Plasma homocysteine and serum CRP were measured at baseline and after 6 months of treatment.

RESULTS

In the genistein group, plasma homocysteine and serum CRP showed no statistically significant difference from baseline (homocysteine: 11.36 +/- 0.39 micromol/l; CRP: 1.73 +/- 0.31 mg/l) to 6 months treatment (homocysteine: 10.72 +/- 0.46 micromol/l; CRP: 2.13 +/- 0.45 mg/l), without any significant difference versus the placebo group (homocysteine: 11.25 +/- 0.43 micromol/l; CRP: 1.74 +/- 0.22 mg/l). In the HRT group there was a slight, but not significant reduction, of plasma homocysteine mean value from baseline (11.21 +/- 0.44 micromol/l) to 6 months treatment (10.45 +/- 0.38 micromol/l); whereas CRP mean value at the end of treatment (3.30 +/- 0.55 mg/l) was significantly higher from baseline (1.61 +/- 0.25 mg/l) (P < 0.01). However, after 6 months, no significant difference existed with the other two groups.

CONCLUSIONS

The phytoestrogen genistein, after 6 months treatment, does not modify the independent cardiovascular risk linked to circulating homocysteine or CRP level. Our experience confirms critical increase of CRP serum level after HRT treatment, but not plasma homocysteine significant variation.

Intranasal 17β-estradiol treatment and Vitamin B12, folate and homocysteine in menopause

OBJECTIVE

This study assessed the effect of intranasal administration of 17beta-estradiol (Aerodiol) on plasma levels of homocysteine, Vitamin B12 and folate in postmenopausal women.

METHODS

In all, 26 symptomatic postmenopausal women who had undergone hysterectomy and oophorectomy at least 12 months previously participated in this 6-month randomized prospective clinical study. Menopause was determined by serum FSH level >30 microIU/ml and serum estradiol concentration <30 pg/ml. Intranasal 17beta-estradiol treatment was given once daily at a standard daily dose of 300 microg to 16 women, and 10 did not receive any treatment.

RESULTS

In the group receiving intranasal 17beta-estradiol, mean (+/-S.D.) plasma homocysteine level decreased significantly from pre-treatment values (from 16.68+/-4.33 to 14.15+/-1.18 nmol/ml, p=0.029) and the mean folate level increased (from 4.11+/-0.80 to 5.64+/-1.87 ng/ml, p=0.012). Vitamin B12 levels showed a tendency towards increasing. In the treated group, significant negative correlations were observed between homocysteine and folate values (r=-0.586, p=0.017) and between homocysteine and Vitamin B12 values (r=-0.672, p=0.004). No significant changes were observed in the untreated group.

CONCLUSION

The reduction in plasma homocysteine levels observed after 6 months' treatment with intranasal 17beta-estradiol may reflect an alteration in folate and Vitamin B12 homeostasis.

The Effect of Hormone Replacement Therapy and Simvastatin on Plasma Homocysteine

BACKGROUND

Homocysteine may be an independent risk factor for coronary artery disease (CAD), and the risk is at least as strong for women as for men. Homocysteine levels are lower in women compared with men, and homocysteine is lower during pregnancy and higher during menopause.

PURPOSE

To investigate the effects of hormone replacement therapy (HRT), simvastatin, and their combination on plasma homocysteine levels, we treated 16 postmenopausal, hypercholesterolemic women with CAD with HRT (0.625 mg conjugated equine estrogens [CEE] combined continuously with 2.5 mg medroxyprogesterone), 20 mg simvastatin, and their combination in a randomized, placebo-controlled study. Each treatment period was 8 weeks long, with a 4-week washout interval. Plasma homocysteine levels were evaluated at the end of each treatment period.

RESULTS

Only HRT, alone and in combination with simvastatin, significantly reduced homocysteine levels compared with placebo (11.82 +/- 0.74 and 12.22 +/- 0.71 vs 13.58 +/- 0.83 micromol/L, respectively, p < 0.05). Simvastatin had no effect (13.02 +/- 0.94 micromol/L), and the combination therapy was not better that monotherapy with HRT.

CONCLUSIONS

Oral HRT reduces homocysteine plasma levels, whereas simvastatin has no effect. If confirmed by randomized, prospective studies with clinical end points, HRT may be considered for women with mild hypercholesterolemia and high homocysteine levels.

Are effects of MTHFR (C677T) genotype on BMD confined to women with low folate and riboflavin intake? Analysis of food records from the Danish osteoporosis prevention study

We have previously found BMD and fracture risk to be significantly associated with the MTHFR (C677T) polymorphism in healthy postmenopausal women in the first years after menopause. Since then, other cohort studies have suggested that sufficient intake of riboflavin and/or folate may have the potential to prevent development of low BMD in women with the TT genotype. This could to some extent explain why this polymorphism is associated with low BMD or fracture in some study populations and not in others. It would also indicate that fractures associated with the TT genotype could be preventable by vitamin B supplementation. We have, therefore, reviewed baseline food record data from our original study to determine if BMD and fracture associations with the MTHFR genotype depended on the intake of folate, riboflavin, or other members of the vitamin B complex, associated with homocysteine metabolism. We analyzed genotype, BMD, and dietary records from 1700 healthy postmenopausal women who participated in the DOPS study. For the assessment of fracture risk, we used longitudinal observations from 854 women in the control group who remained compliant with their initial allocation of no treatment. Riboflavin intake was significantly correlated with femoral neck (FN) BMD in women with the TT genotype (r = 0.24, P < 0.01). FN and lumbar spine (LS) BMD were only associated with the MTHFR genotype in the lowest quartile of riboflavin intake. At the FN, similar threshold effects were shown for folate, vitamin B12, and vitamin B6. Among these vitamin B complex members, stepwise regression analysis identified riboflavin as the only significant predictor of FN BMD in the TT genotype. In conclusion, we confirm reports that BMD in the MTHFR TT genotype is only significantly reduced in the lowest quartile of riboflavin, B12, B6, and folate intake, at least at the time of menopause. Vitamin B supplementation would only be expected to benefit BMD in about 2% of the population, i.e., those with the TT genotype and low vitamin B intake.

The effect of hormone therapy on plasma homocysteine levels: a randomized clinical trial*

OBJECTIVE

An elevated plasma homocysteine level is a risk factor for cardiovascular diseases. Hormone therapy (HT) may reduce fasting plasma homocysteine levels. We studied 80 postmenopausal women to determine the effect of medroxyprogesterone acetate (MPA) combined with conjugated equine estrogens (CEE) on fasting plasma homocysteine levels.

DESIGN

In a randomized, double blind, prospective, placebo-controlled study, we randomly assigned 80 healthy postmenopausal women between CEE 0.625 mg/d combined with MPA 2.5 mg/d (n = 20), CEE 0.625 mg/d combined with MPA 5 mg/d (n = 20), unopposed CEE 0.625 mg/d (n = 20), and placebo (n = 20) all given for a duration of 6 months. Fasting plasma homocysteine levels were measured before and at the end of the treatment.

RESULTS

Before treatment, plasma homocysteine concentrations were similar in all groups. After 6 months of unopposed CEE, the mean fasting plasma homocysteine levels decreased by 19.02% when compared with baseline levels (P < 0.05). The mean fasting plasma homocysteine concentrations decreased by 17.63% and 19.56% from baseline in both the CEE plus MPA 2.5 mg/d and CEE plus MPA 5 mg/d groups, respectively (P < 0.05 for each group). In contrast, plasma homocysteine levels increased by 11.66% in the placebo group. The homocysteine lowering effect did not differ significantly among the three groups of women receiving unopposed CEE alone and CEE plus MPA at two different doses.

CONCLUSION

Six months of estrogen therapy (ET) and combined estrogen-progestogen therapy (EPT) significantly lower fasting plasma homocysteine levels in healthy postmenopausal women with equal efficacy.

MTHFR Polymorphisms, Diet, HRT, and Breast Cancer Risk: The Multiethnic Cohort Study

Methylenetetrahydrofolate reductase (MTHFR) is a key regulatory enzyme in the metabolism of folate, a nutrient which has recently been found to be inversely related to breast cancer in women who drink alcohol. Two common variants in the MTHFR gene (C677T and A1298C) have been associated with a reduced activity of this enzyme, thereby increasing the availability of folate for thymidylate and purine synthesis. We investigated the relationship of these variants with invasive breast cancer in a case-control study of 1,189 cases and 2,414 controls nested within the Multiethnic Cohort Study. The Multiethnic Cohort Study is a large prospective study of men and predominantly postmenopausal women of Japanese, White, African American, Latino, and Native Hawaiian origin, residing in Hawaii and Los Angeles. We found an overall nonsignificant, weak inverse association between breast cancer risk and the 677TT genotype and no association with the 1298C variant. The odds ratio [OR and 95% confidence interval (95% CI)] for the 677CC, 677CT, and 677TT genotypes were 1.00, 0.98 (0.83-1.15), and 0.86 (0.67-1.09), respectively. Those for the 1298AA, 1298AC, and 1298CC genotypes were 1.00, 0.93 (0.79-1.08), and 1.20 (0.88-1.65), respectively. However, the inverse association with the 677TT genotype was stronger (OR, 0.62; 95% CI 0.39-0.98) among women who were on hormone replacement therapy (HRT) at baseline, and the increased breast cancer risk due to HRT was not observed in women with the 677TT genotype. An increased breast cancer risk was suggested for alcohol intake &gt;10 g/d, when compared with nondrinkers, but only among HRT users with the 677CC genotype (OR, 1.51; 95% CI, 0.96-2.37). Folate intake exhibited no modifying effect on the genotype-breast cancer relationship. These findings suggest that the MTHFR 677TT genotype may confer a 40% decreased breast cancer risk in postmenopausal women using HRT. This is consistent with the role of MTHFR in facilitating the flow of folate for thymidylate and purine synthesis and with the increased nucleic acid need resulting from the hyperproliferative effect of HRT on mammary epithelial cells.

Homocysteine levels in newly admitted schizophrenic patients

We previously found a marked elevation of plasma homocysteine in young male schizophrenic patients in hospital. It seemed important to determine if this finding is already present in newly admitted schizophrenic patients. Serum homocysteine levels were studied in 184 consecutively admitted schizophrenic patients and 305 control subjects from an employee screening program. Homocysteine levels were markedly increased in this population of newly admitted schizophrenic patients, especially in young males. Newly admitted male schizophrenic patients have elevated homocysteine levels that cannot be explained on the basis of poor hospital nutrition. Smoking may raise homocysteine by 1-2 microM/L but this is not a large enough effect to explain our findings.

Effect of oral or transdermal hormone replacement therapy on homocysteine levels: a randomized clinical trial

OBJECTIVE

Aim of this randomized trial was evaluate the effect on homocysteine plasma levels of two different hormone replacement therapy (HRT) formulations in a group of late postmenopausal women.

METHODS

Eligible for this study were women: in postmenopause since 5 years or more (confirmed from FSH level > or = 40 mIU/l); with body mass index (BMI) < or = 35; without endocrine, hepatic or renal diseases; not current users of vitamin B or folic acid supplements; not users of any lipid-lowering drugs and sex steroids in the 6 months before trial entry. Group A: oral estradiol valerate 2 mg per day per oral normegestrol acetate 2.5 mg per day (n = 98) for 12 months; Group B: a weekly patch releasing estradiol (50 microg per day) per oral normegestrol acetate 2.5 mg per day (n = 101) for 12 months.

RESULTS

The mean values of the homocysteine levels in the group A and B at baseline, 3, 6 and 12 months were 7.9 and 9.1, 8.7 and 8.9, 9.3 and 10.2, 9.6 and 10.2, respectively, the differences between the two treatments were not statistically significant (time by treatment interaction, P = 0.32). Otherwise, the changes of homocysteine level at the four visits was statistically significant (P = 0.0001) in both groups. In particular, in the oral treatment group homocysteine levels increased from baseline of 10.5% at 3 months, of 17.2% after 6 months of therapy and of 21.9% at the end of the study; in the transdermal group, after a little decrease at 3 months (1.5%), the increases were of 12.1 and 12.9%, respectively.

CONCLUSIONS

This study does not show any different effect of oral and transdermal treatment with estradiol plus normegestrol acetate on homocysteine levels. Further it does not support previous suggestion of a lowering effect of HRT on plasma homocysteine.

Effects of oral and transdermal 17 beta-estradiol combined with progesterone on homocysteine metabolism in postmenopausal women: a randomised placebo-controlled trial

Mild hyperhomocysteinemia is a risk factor for both ischaemic heart disease and venous thromboembolism. The effects of transdermal estrogen replacement therapy (ERT) on homocysteine metabolism in postmenopausal women have scarcely been investigated. This clinical trial aimed to estimate the effects of combined hormone replacement therapy on the fasting total homocysteine levels according to the estrogen route of administration. We enrolled 196 postmenopausal women, who were randomly allocated to receive on a continuous basis either 1mg of 17 beta-estradiol orally (n = 63) or 50 microg transdermally (n = 68) per day, both combined with a daily intake of 100 mg progesterone, or placebo (n = 65) over a period of 6 months. Neither oral nor transdermal ERT significantly affected total plasma homocysteine levels or red-blood cell folate levels. However, oral ERT significantly decreased plasma vitamin B12 levels compared to placebo (mean relative variation difference over 6 months between oral ERT and placebo: -11.7% (95%CI, -21 to -2%) whereas transdermal ERT did not display any significant effects. Our data show that transdermal ERT as well as low dose of oral ERT does not significantly affect the homocysteine metabolism. This finding does not support a role for transdermal estrogen in the prevention of ischaemic heart disease in postmenopausal women.

Effect of hormone replacement therapy and tibolone on serum total homocysteine levels in postmenopausal women

OBJECTIVE

To assess the effect of continuous combined hormone replacement therapy (HRT) or tibolone on serum total homocysteine (tHcy) levels in postmenopausal women.

STUDY DESIGN

Ninety-five postmenopausal women aged 41-68 years were included in the study. Seventy-three women with climacteric complaints, osteopenia or osteoporosis received either conjugated equine estrogens 0.625 mg combined with medroxyprogesterone acetate 5 mg (CEE/MPA, n=31) or tibolone 2.5 mg (n=42). Twenty-two healthy women, matched for chronological and menopausal age, served as controls. Serum tHcy levels were assessed at baseline, 6, 12 and 18 months.

RESULTS

No difference was recorded between groups regarding demographic characteristics or mean baseline serum tHcy. Serum tHcy levels decreased significantly in the CEE/MPA compared to baseline (change at 18 months: -3.9%, P<0.05). The magnitude of the decrease was higher in the subgroup of women with baseline tHcy levels above the median (change at 18 months: -15.0%, P<0.01). No change in tHcy levels was detected in the tibolone group throughout the study period, either in the whole group (change at 18 months: 1.9%, NS) or in the subgroup with baseline tHcy levels above the median (change at 18 months: -3.23%, NS).

CONCLUSION

Continuous CEE/MPA reduces tHcy especially in women with high pretreatment tHcy levels. Tibolone has no effect on serum tHcy levels at least during the first 18 months of therapy. Larger studies with longer follow-up are required to confirm these results.

Positive impact of hormone replacement therapy on the fibrinolytic system: a long-term randomized controlled study in healthy postmenopausal women

BACKGROUND

The mechanisms by which postmenopausal hormone replacement therapy (HRT) may influence risk of cardiovascular disease are still unclear. Impaired fibrinolytic function is associated with an enhanced risk of cardiovascular disease and therefore the effect of HRT on fibrinolysis may be of importance.

OBJECTIVES

To investigate the prolonged effect of HRT on the fibrinolytic system and to determine whether two common polymorphisms in the plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (t-PA) genes modulate this effect.

METHODS

Healthy postmenopausal women (n = 248) were randomized to HRT (n = 122) or no substitution (n = 126) 5 years prior to investigation.

RESULTS

Significantly higher values of t-PA activity and lower values of PAI-1 activity and PAI-1 antigen were found in the HRT group compared with the control group. This effect was independent of smoking and without influence from the two common polymorphisms PAI-1 -675(4G/5G) and t-PA intron8ins311. Furthermore, no difference between opposed estrogen (with norethisterone acetate as the gestagen component) and unopposed estrogen therapy was found. Both an intention-to-treat and a per-protocol analysis were performed and similar results were obtained.

CONCLUSIONS

Long-term treatment with HRT in healthy postmenopausal women was found to be associated with a beneficial fibrinolytic profile. This effect was found independent of smoking status, opposed and unopposed estrogen therapy had equal effect, and no influence of the two common polymorphisms PAI-1-675(4G/5G) and t-PA intron8ins311 was found. This effect of HRT on fibrinolytic capacity may be one of the beneficial effects of HRT in relation to cardiovascular diseases.

Effect of long-term hormone replacement therapy on tissue factor pathway inhibitor and thrombin activatable fibrinolysis inhibitor in healthy postmenopausal women: a randomized controlled study

It was recently reported from the Women's Health Initiative that healthy women using combined hormone replacement therapy (HRT) for 5 years have an increased cardiovascular risk. We hypothesize that the increased risk is confined to subgroups of atherosclerotic women. Such women may have higher arterial tissue factor expression and higher thrombin formation, and changes in tissue factor pathway coagulation inhibitor (TFPI) and thrombin activatable fibrinolysis inhibitor (TAFI) may be deleterious. Healthy postmenopausal women (n = 719) were randomized to hormone therapy [n = 357; opposed (n = 290) and unopposed (n = 67)] or no treatment (n = 362). Plasma TFPI and TAFI and the TFPI -287T/C and TAFI -438G/A polymorphisms were measured 5-6 years after randomization. Concentrations of TFPI were significantly lower in the hormone group than in the control group (P < 0.001) and in all genotypes of the TFPI polymorphism. Overall, concentrations of TAFI did not differ between the two groups but were reduced by hormone therapy in homozygotes for the rare TAFI -438 A allele (P < 0.05). The hormone effects on TFPI and TAFI were similar in smokers and non-smokers and in women using unopposed and opposed therapy. The observed decrease in TFPI may contribute to the increased cardiovascular risk associated with HRT.

A common methylenetetrahydrofolate reductase (C677T) polymorphism is associated with low bone mineral density and increased fracture incidence after menopause: longitudinal data from the Danish osteoporosis prevention study

A polymorphism in the gene encoding methylenetetrahydrofolate reductase (MTHFR) has recently been associated with bone mineral density (BMD) in postmenopausal Japanese women. It is not known whether this effect is also present in European populations and whether it is caused by lower peak bone mass or accelerated postmenopausal bone loss. MTHFR genotyping was done in 1748 healthy postmenopausal Danish women participating in a prospective study of risk factors for osteoporosis. At the time of enrollment, 3-24 months after last menstrual period, the less prevalent genotype (TT, 8.7% of the population) was associated with significantly lower BMD at the femoral neck (ANOVA, p < 0.05), total hip (p < 0.01), and spine (p < 0.05 adjusted for lifestyle covariates, p = 0.06 without adjustment). The mean difference was between 0.1 and 0.3 SD, depending on measurement site. MTHFR genotype added significantly to prediction of BMD by weight and age. Fracture incidence was increased more than 2-fold in subjects with the TT genotype (risk ratio [RR], 2.6; 95% CI 1.2-5.6). This remained significant when the Cox analysis was controlled for BMD (RR, 2.4; 95% CI 1.1-5.2). No differences in serum osteocalcin, bone-specific alkaline phosphatase, and 25-OH-vitamin D were found between genotypes. The response to hormone replacement therapy (HRT) did not differ, but the association of the TT genotype with reduced BMD was maintained at the total hip after 5 years of HRT. The MTHFR TT genotype is associated with low BMD and increased fracture incidence in early postmenopausal women.