Understanding the divergent data on postmenopausal hormone therapy

Hormone replacement therapy and myocardial infarction and stroke in postmenopausal Korean women

OBJECTIVE

This study aimed to investigate the association of hormone replacement therapy (HRT) use, type, duration and age of commencement with myocardial infarction (MI) and stroke in postmenopausal Korean women.

METHODS

This nested case-control study used data from the National Health Insurance Service database to analyze 2017 data from women aged ≥50 years and diagnosed with natural menopause between 2004 and 2007. Among 356,160 eligible women, 36,446 used HRT for ≥1 year and 319,714 did not (controls). These two groups were matched 1:1 for statistical analysis. Type and duration were categorized into three categories.

RESULTS

Women who started estrogen-progestogen therapy (EPT) or estrogen therapy (ET) in their 50s, or EPT or tibolone in their ≥60s exhibited a lower stroke risk than controls. MI risk was lower among women who used tibolone - regardless of duration - or EPT or ET for 1-3 years than among controls. Stroke risk was lower with tibolone use for ≥5 years or with EPT or ET use for 1-3 years or ≥5 years than non-users.

CONCLUSION

Our study may support the beneficial effect of HRT by showing that Korean postmenopausal women who used HRT at a relatively younger and healthier age had a relative benefit for MI and stroke.

Association between estrogen replacement therapy and heart failure in postmenopausal women: A systematic review and meta-analysis

BACKGROUND

Based on past epidemiological investigations, the cardiovascular role of estrogen replacement therapy (ERT) in postmenopausal women has always been controversial. The real efficacy of ERT for heart failure (HF) among postmenopausal women remains to be further investigated. This article is based on research into European and American populations.

PURPOSE

To determine the impact of estrogen replacement therapy on HF using meta-analysis.

METHODS AND MATERIAL

Electronic literature was searched on Web of Science, PubMed, and Embase databases to identify randomized controlled trials (RCTs) comparing the hospitalization for heart failure between ERT users and non-users among postmenopausal women. Pairs of reviewers screened eligible articles independently, extracted data, and evaluated the risk of bias. Summary relative risks were estimated for the composite endpoint of first hospitalized heart failure and admission to the hospital for heart failure.

RESULTS

A pooled study of five randomized controlled trials found that estrogen replacement therapy had no significant effect on the composite endpoint in postmenopausal women, with a relative risk of 1.02 (95% CI 0.94-1.10).

CONCLUSION

This systematic review demonstrated that estrogen replacement therapy did not significantly change the risk of first hospitalized heart failure and admission to the hospital for heart failure in postmenopausal women.

Measurements of Postmenopausal Serum Estradiol Levels and Cardiovascular Events: A Systematic Review

Background

Cardiovascular disease (CVD) is the leading cause of death among female patients and its likelihood increases following menopause. However, whether estradiol levels are related to CVD remains unknown. We aimed to determine the association between serum estradiol levels and cardiovascular (CV) events in postmenopausal females.

Methods

Electronic databases (MEDLINE, Embase) were searched systematically from inception to October 2022. Studies were eligible for inclusion if they included the following: (i) postmenopausal females; (ii) examination of the association between total serum estradiol levels and CV events (CV mortality, CVD, coronary heart disease, myocardial infarction, stroke, venous thromboembolism, heart failure, and CV hospitalization); (iii) original data (randomized controlled trial, quasi-experimental, cohort, case-control, or cross-sectional study). A narrative synthesis was completed because the data were not amenable to meta-analysis.

Results

Of the 9026 citations retrieved, 8 articles were included, representing a total of 5635 women. The risk-of-bias was fair, and considerable heterogeneity was present. In those not using menopausal hormone therapy, 3 studies demonstrated mixed results between estradiol levels and risk of coronary heart disease, and 1 study showed that higher estradiol levels were associated with an increased risk of myocardial infarction. No significant associations were present between estradiol levels and the remaining events (ie, CV mortality, heart failure, CVD, and stroke).

Conclusions

The association between serum estradiol levels and CV events in postmenopausal females remains unclear. Further studies assessing this association are warranted, given the elevated CVD risk in this population.

The VANCO Trial Findings Are Generalizable to a North American Trauma Registry

OBJECTIVES

To estimate the generalizability of treatment effects observed in the VANCO trial to a broader population of patients with tibial plateau or pilon fractures.

METHODS

Design and Setting: Clinical trial data from 36 United States trauma centers and Trauma Quality Programs registry data from more than 875 Level I-III trauma centers in the United States and Canada.Patient Selection Criteria: Patients enrolled in the VANCO trial treated with intrawound vancomycin powder from January 2015 to June 2017 and 31,924 VANCO-eligible TQP patients admitted in 2019 with tibial plateau and pilon fractures.Outcome Measure and Comparisons: Deep surgical site infection and gram-positive deep surgical site infection estimated in the TQP sample weighed by the inverse probability of trial participation.

RESULTS

The 980 patients in the VANCO trial were highly representative of 31,924 TQP VANCO-eligible patients (Tipton generalizability index 0.96). It was estimated that intrawound vancomycin powder reduced the odds of deep surgical infection by odds ratio (OR) = 0.46 (95% confidence interval [CI] 0.25-0.86) and gram-positive deep surgical infection by OR = 0.39 (95% CI, 0.18-0.84) within the TQP sample of VANCO-eligible patients. For reference, the trial average treatment effects for deep surgical infection and gram-positive deep surgical infection were OR = 0.60 (95% CI, 0.37-0.98) and OR = 0.44 (95% CI, 0.23-0.80), respectively.

CONCLUSIONS

This generalizability analysis found that the inferences of the VANCO trial generalize and might even underestimate the effects of intrawound vancomycin powder when observed in a wider population of patients with tibial plateau and pilon fractures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

An empirical comparison of the harmful effects for randomized controlled trials and non-randomized studies of interventions

Introduction: Randomized controlled trials (RCTs) are the gold standard to evaluate the efficacy of interventions (e.g., drugs and vaccines), yet the sample size of RCTs is often limited for safety assessment. Non-randomized studies of interventions (NRSIs) had been proposed as an important alternative source for safety assessment. In this study, we aimed to investigate whether there is any difference between RCTs and NRSIs in the evaluation of adverse events. Methods: We used the dataset of systematic reviews with at least one meta-analysis including both RCTs and NRSIs and collected the 2 × 2 table information (i.e., numbers of cases and sample sizes in intervention and control groups) of each study in the meta-analysis. We matched RCTs and NRSIs by their sample sizes (ratio: 0.85/1 to 1/0.85) within a meta-analysis. We estimated the ratio of the odds ratios (RORs) of an NRSI against an RCT in each pair and used the inverse variance as the weight to combine the natural logarithm of ROR (lnROR). Results: We included systematic reviews with 178 meta analyses, from which we confirmed 119 pairs of RCTs and NRSIs. The pooled ROR of NRSIs compared to that of RCTs was estimated to be 0.96 (95% confidence interval: 0.87 and 1.07). Similar results were obtained with different sample size subgroups and treatment subgroups. With the increase in sample size, the difference in ROR between RCTs and NRSIs decreased, although not significantly. Discussion: There was no substantial difference in the effects between RCTs and NRSIs in safety assessment when they have similar sample sizes. Evidence from NRSIs might be considered a supplement to RCTs for safety assessment.

Oral Contraceptives, Hormone Replacement Therapy, and Stroke Risk

BACKGROUND

Millions of women worldwide use exogenous hormones as oral contraceptives or hormone replacement therapy. Still, time-dependent and long-term consequences of exogenous hormones on stroke risk remains unclear.

METHODS

We examined the association between self-reported oral contraceptive and hormone replacement therapy use and stroke risk in 257 194 women from the UK Biobank, born between 1939 and 1970. Outcomes included any type of stroke, ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. Exposures were analyzed as time-varying variables in Cox regression models.

RESULTS

During first year of oral contraceptive use, an increased event rate of any stroke was observed (hazard ratio [HR], 2.49 [95% CI, 1.44-4.30]), while the hazards were found to be comparable during remaining years of use (HR, 1.00 [95% CI, 0.86-1.14]), compared with nonusers. Similarly, first year of hormone replacement therapy use was associated with higher hazard rates of any stroke (HR, 2.12 [95% CI, 1.66-2.70]), as well as cause-specific stroke, including ischemic stroke (HR, 1.93 [95% CI, 1.05-3.57]) and subarachnoid hemorrhage (HR, 2.17 [95% CI, 1.25-3.78]), which remained increased for any stroke during remaining years of use (HR, 1.18 [95% CI, 1.05-1.31]), and after discontinuation (HR, 1.16 [95% CI, 1.02-1.32]).

CONCLUSIONS

Oral contraceptive use and hormone replacement therapy were associated with an increased risk of stroke, especially during the first year of use, possibly due to immediate changes in hemostatic balance. This study provides new insights on the effects of hormone exposure on stroke risk and provide evidence of not only an overall risk but also a pronounced effects seen in the beginning of treatment.

The Association Between Route of Post-menopausal Estrogen Administration and Blood Pressure and Arterial Stiffness in Community-Dwelling Women

Background

Postmenopausal hormone therapy (HT) is associated with increased cardiovascular risk. Although the route of estrogen administration may play a role in mediating risk, previous studies have not controlled for concomitant progestin use.

Objective

To investigate the association between the route of estrogen therapy (oral or non-oral) HT use, without concomitant progestin, and blood pressure and arterial stiffness in postmenopausal women.

Methods

Systolic blood pressure [SBP], diastolic blood pressure [DBP]), arterial stiffness (aortic pulse wave velocity [aPWV] and augmentation index at 75 beats per minute [AIx]) were measured using a validated automated brachial cuff-based oscillometric approach (Mobil-O-Graph) in a community-dwelling sample of 328 women.

Results

Fifty-five participants (16.8%) were ever users (current and past use) of estrogen-only HT (oral [n = 16], transdermal [n = 20], vaginal [n = 19]), and 223 were never HT users (control). Ever use of oral estrogen was associated with increased SBP and DBP (Oral: SBP: 137 ± 4 mmHg, DBP: 79 ± 2 mmHg) compared to use of non-oral estrogen (transdermal: SBP: 118 ± 2 mmHg, DBP: 73 ± 1 mmHg; p < 0.01 & p = 0.012, respectively; vaginal: SBP: 123 ± 2 mmHg DBP: 73 ± 2 mmHg; p = 0.02 & p = 0.01, respectively.) and controls (SBP: 124 ± 1 mmHg, DBP: 74 ± 1 mmHg, p = 0.03, p = 0.02, respectively) after adjustment for covariates. aPWV was higher in oral estrogen ever users (9.9 ± 1 m/s) compared to non-oral estrogen (transdermal: 8.6 ± 0.3 m/s, p < 0.01; vaginal: 8.8 ± 0.7 m/s, p = 0.03) and controls (8.9 ± 0.5 m/s, p = 0.03) but these associations were no longer significant after adjustment for covariates. AIx was higher in oral estrogen (29 ± 2 %) compared to non-oral estrogen (transdermal: 16 ± 2 %; vaginal: 22 ± 1.7 %) but this association was no longer significant after adjustment for covariates (p = 0.92 vs. non-oral; p = 0.74 vs. control).

Conclusion

Ever use of oral estrogen was associated with increased SBP and DBP compared to non-oral estrogen use and no use. Given the cardiovascular risk associated with both menopause and increased blood pressure, further studies are required exploring the potential benefits of non-oral estrogen in postmenopausal women.

Early menopause is associated with increased risk of retinal vascular occlusions: a nationwide cohort study

This nationwide population-based cohort study evaluated the association between female reproductive factors and the incidence of retinal vein occlusion (RVO) and retinal artery occlusion (RAO) using data provided by the Korea National Health Insurance Service. A total of 2,289,347 postmenopausal women over 50 years of age who participated in both national health screening and cancer screening in 2013 or 2014 were included. Data on female reproductive factors, including age at menarche, age at menopause, parity, history of hormone replacement therapy, and oral contraceptive pill usage, were collected. Patients were followed up until December 2018, and incident cases of RVO and RAO were identified using registered diagnostic codes from claim data. During an average follow-up period of 4.90 years, 7461 and 1603 patients were newly diagnosed with RVO and RAO, respectively. In the multivariable-adjusted Cox proportional hazard model, patients who experienced menopause after 55 years of age had a lower risk of RVO and RAO development compared to those who had menopause before 45 years of age, with a hazard ratio (95% confidence interval) of 0.83 (0.76–0.95) for RVO and 0.80 (0.66‒0.98) for RAO. In conclusion, early menopause was an independent risk factor for future development of RVO and RAO.

Oral postmenopausal hormone therapy and genetic risk on venous thromboembolism: gene-hormone interaction results from a large prospective cohort study

OBJECTIVE

Oral postmenopausal hormone therapy (HT) has been shown to be associated with venous thromboembolism (VTE), but whether this association is modified by VTE-associated genetic susceptibility is unknown. We examined interactions between oral HT use and a genetic risk score (GRS) of VTE.

METHOD

Eligible women were postmenopausal women who had data on oral HT use, VTE incidence between 1990 and 2012, and genetic data in the Nurses' Health Study. We built a GRS aggregating 16 VTE-related genetic variants. We used Cox regression to estimate associations of HT use with incident VTE and assessed interactions between HT use and VTE GRS. We also estimated incidence of VTE between age 50 and 79 years for groups of women defined by HT use and VTE GRS.

RESULTS

We identified 432 incident VTE cases. Current HT users were at higher risk of VTE than never users (HR: 1.9, 95% CI: 1.5-2.6), with slightly higher risk for estrogen plus progestin HT than estrogen only (HR: 2.4 vs 1.9). The GRS was associated with VTE risk (HR comparing 4th quartile to 1st: 2.0, 95% CI: 1.2-3.4). We did not observe significant multiplicative interactions between HT use and GRS. The estimated VTE risk difference (per 10,000 person-years) comparing 50-year-old current HT users to never users was 22.5 for women in the highest GRS quartile and 9.8 for women in the lowest GRS quartile.

CONCLUSION

The VTE GRS might inform clinical guidance regarding the balance of risks and benefits of HT use, especially among younger women.

Management of Cardiovascular Risk in Perimenopausal Women with Diabetes

Cardiovascular disease is the primary cause of mortality in women and men with diabetes. Due to age and worsening of risk factors over the menopausal transition, risk of coronary heart disease events increases in postmenopausal women with diabetes. Randomized studies have conflicted regarding the beneficial impact of estrogen therapy upon intermediate cardiovascular disease markers and events. Therefore, estrogen therapy is not currently recommended for indications other than symptom management. However, for women at low risk of adverse events, estrogen therapy can be used to minimize menopausal symptoms. The risk of adverse events can be estimated using risk engines for the calculation of cardiovascular risk and breast cancer risk in conjunction with screening tools such as mammography. Use of estrogen therapy, statins, and anti-platelet agents can be guided by such calculators particularly for younger women with diabetes. Risk management remains focused upon lifestyle behaviors and achieving optimal levels of cardiovascular risk factors, including lipids, glucose, and blood pressure. Use of pharmacologic therapies to address these risk factors, particularly specific hypoglycemic agents, may provide some additional benefit for risk prevention. The minimal benefit for women with limited life expectancy and risk of complications with intensive therapy should also be considered.

Estrogen activates endothelial exocytosis

Estrogen therapy is used to treat patients with post-menopausal symptoms, such as hot flashes and dyspareunia. Estrogen therapy also decreases the risk of fractures from osteoporosis in post-menopausal women. However, estrogen increases the risk of venous thromboembolic events, such as pulmonary embolism, but the pathways through which estrogen increase the risk of thromboembolism is unknown. Here, we show that estrogen elicits endothelial exocytosis, the key step in vascular thrombosis and inflammation. Exogenous 17β-estradiol (E2) stimulated endothelial exocytosis of Weibel-Palade bodies (WPBs), releasing von Willebrand factor (vWF) and interleukin-8 (IL-8). Conversely, the estrogen antagonist ICI-182,780 interfered with E2-induced endothelial exocytosis. The ERα agonist propyl pyrazole triol (PPT) but not the ERβ agonist diarylpropionitrile (DPN) induced vWF release, while ERα silencing counteracted vWF release by E2, suggesting that ERα mediates this effect. Exocytosis triggered by E2 occurred rapidly within 15 min and was not inhibited by either actinomycin D or cycloheximide. On the contrary, it was inhibited by the pre-treatment of U0126 or SB203580, an ERK or a p38 inhibitor, respectively, suggesting that E2-induced endothelial exocytosis is non-genomically mediated by the MAP kinase pathway. Finally, E2 treatment enhanced platelet adhesion to endothelial cells ex vivo, which was interfered with the pre-treatment of ICI-182,780 or U0126. Taken together, our data show that estrogen activates endothelial exocytosis non-genomically through the ERα-MAP kinase pathway. Our data suggest that adverse cardiovascular effects such as vascular inflammation and thrombosis should be considered in patients before menopausal hormone treatment.

Empirical use of causal inference methods to evaluate survival differences in a real-world registry vs those found in randomized clinical trials

With heighted interest in causal inference based on real-world evidence, this empirical study sought to understand differences between the results of observational analyses and long-term randomized clinical trials. We hypothesized that patients deemed "eligible" for clinical trials would follow a different survival trajectory from those deemed "ineligible" and that this factor could partially explain results. In a large observational registry dataset, we estimated separate survival trajectories for hypothetically trial-eligible vs ineligible patients under both coronary artery bypass surgery (CABG) and percutaneous coronary intervention (PCI). We also explored whether results would depend on the causal inference method (inverse probability of treatment weighting vs optimal full propensity matching) or the approach to combine propensity scores from multiple imputations (the "across" vs "within" approaches). We found that, in this registry population of PCI/CABG multivessel patients, 32.5% would have been eligible for contemporaneous RCTs, suggesting that RCTs enroll selected populations. Additionally, we found treatment selection bias with different distributions of propensity scores between PCI and CABG patients. The different methodological approaches did not result in different conclusions. Overall, trial-eligible patients appeared to demonstrate at least marginally better survival than ineligible patients. Treatment comparisons by eligibility depended on disease severity. Among trial-eligible three-vessel diseased and trial-ineligible two-vessel diseased patients, CABG appeared to have at least a slight advantage with no treatment difference otherwise. In conclusion, our analyses suggest that RCTs enroll highly selected populations, and our findings are generally consistent with RCTs but less pronounced than major registry findings.

Some statistical memes which sound correct but aren't quite: Application to the analysis of observational databases used in learning health systems

We consider four memes, correct within the context of randomized trials but requiring modification for the analysis of the observational databases typically associated with learning health systems: (a) the right answer always requires randomization; (b) a bigger database is always a better database; (c) statistical adjustment always works if based on a large enough database; and (d) always make a formal adjustment when testing multiple hypotheses. The rationale for these memes within the context of randomized trials is discussed, and the memes are restated in a fashion that is consistent with learning health systems.

Synaptic plasticity in hippocampal CA1 neurons and learning behavior in acute kidney injury, and estradiol replacement in ovariectomized rats

Background

Neurological complications may occur in patients with acute or chronic renal failure; however, in cases of acute renal failure, the signs and symptoms are usually more pronounced, and progressed rapidly. Oxidative stress and nitric oxide in the hippocampus, following kidney injury may be involved in cognitive impairment in patients with uremia. Although many women continue taking hormone therapy for menopausal symptom relief, but there are also some controversies about the efficacy of exogenous sex hormones, especially estrogen therapy alone, in postmenopausal women with kidney injury. Herein, to the best of our knowledge for the first time, spatial memory and synaptic plasticity at the CA1 synapse of a uremic ovariectomized rat model of menopause was characterized by estradiol replacement alone.

Results

While estradiol replacement in ovariectomized rats without uremia, promotes synaptic plasticity, it has an impairing effect on spatial memory through hippocampal oxidative stress under uremic conditions, with no change on synaptic plasticity. It seems that exogenous estradiol potentiated the deleterious effect of acute kidney injury (AKI) with increasing hippocampal oxidative stress.

Conclusions

Although, estrogen may have some positive effects on cognitive function in healthy subjects, but its efficacy in menopause subjects under uremic states such as renal transplantation, needs to be further investigated in terms of dosage and duration.

Cardiovascular Disease Risk Across a Spectrum of Adverse Plasma Lipid Combinations by Gender and Glycemic Status

High triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) and high non-HDL-C levels are risk factors for cardiovascular disease (CVD). It is unclear whether the combinations of their adverse changes are related with CVD risk in different gender and diabetes status, particularly in Chinese population. This study aims to evaluate the CVD risk associated with different adverse lipid combinations. A total of 38,989 participants from Chinese Multicenter Longitudinal Health Management Cohorts (mean age 42 years; 62% male) without baseline CVD were followed up for incident CVD from 2007 to 2015. Participants with various combinations of baseline TG, non-HDL-C, and HDL-C levels within- or out of range according to Adult Treatment Panel III were grouped into 8 distinct lipid categories. Cox models estimated the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of different lipid categories for CVD. After multivariable adjustment, a low level of HDL-C combined with either a high level of non-HDL-C alone or TG alone were associated with increased CVD risk with adjusted HRs (95% CIs) of 1.77 (1.36 to 2.30) and 2.08 (1.30 to 3.34) in male participants. Diabetic participants with high non-HDL-C and low HDL-C levels (adjusted HR 2.93, 95% CI 1.15 to 7.46), and non-diabetic participants with high TG and low HDL-C levels (adjusted HR 1.73, 95% CI 1.33 to 2.26) had greater risk of incident CVD. These relations remained significant when limited analysis to participants with normal LDL-C levels of <3.4 mmol/L, indicating the various combinations of out-of-range lipid profiles other than LDL-C are associated with different CVD risk and the associations depend on gender and glycemic status.

The associations of lipids and lipid ratios with stroke: A prospective cohort study

Lipids and lipid ratios have been proven to be associated with cardiovascular disease; however, their relationships with stroke and stroke subtypes had not been fully understood. This study aims to assess the associations of lipids and lipid ratios with type-specific stroke and compare their predictive capacities for stroke occurrence. In this prospective cohort study, a total of 42 005 Chinese participants aged 20 to 80 who were free of stroke at baseline were included and selected into subgroups of stroke subtypes (ischemic, hemorrhagic, and total). Total stroke outcome included a combination of ischemic and hemorrhagic stroke. Over an average follow-up of 3.6 years, 781 participants developed stroke (623 ischemic and 158 hemorrhagic). In men, the highest TC/HDL-C quartile was significantly associated with increased ischemic stroke risk (multivariable-adjusted hazard ratio [HR], 1.52, 95% confidence interval [CI], 1.14-2.03) and total stroke risk (HR, 1.45, 95% CI, 1.12-1.87), and TC/HDL-C had the highest area under the receiver operating characteristic curve (AUC) for predicting ischemic (AUC, 0.868) and total stroke (AUC, 0.874). In women, the highest TG quartile was significantly associated with increased risk of ischemic (HR, 1.99, 95% CI, 1.11-3.59) and total stroke (HR, 1.85, 95% CI, 1.07-3.20), with AUCs of 0.850 and 0.861, respectively. No lipid variables were significantly associated with hemorrhagic stroke in both sex. In conclusion, TC/HDL-C ratio may better predict stroke risk in men, whereas TG was more valuable in predicting stroke risk in women. TC/HDL-C and TG may help to discriminate high stroke risk individuals and serve as potential targets for stroke prevention.

Exploring Selection Bias by Causal Frailty Models: The Magnitude Matters

Counter-intuitive associations appear frequently in epidemiology, and these results are often debated. In particular, several scenarios are characterized by a general risk factor that appears protective in particular subpopulations, for example, individuals suffering from a specific disease. However, the associations are not necessarily representing causal effects. Selection bias due to conditioning on a collider may often be involved, and causal graphs are widely used to highlight such biases. These graphs, however, are qualitative, and they do not provide information on the real life relevance of a spurious association. Quantitative estimates of such associations can be obtained from simple statistical models. In this study, we present several paradoxical associations that occur in epidemiology, and we explore these associations in a causal, frailty framework. By using frailty models, we are able to put numbers on spurious effects that often are neglected in epidemiology. We discuss several counter-intuitive findings that have been reported in real life analyses, and we present calculations that may expand the understanding of these associations. In particular, we derive novel expressions to explain the magnitude of bias in index-event studies.

Hormone therapy and clinical and surrogate cardiovascular endpoints in women with chronic kidney disease: a systematic review and meta-analysis

OBJECTIVE

Women with chronic kidney disease (CKD) experience kidney dysfunction-mediated premature menopause. The role of postmenopausal hormone therapy (HT) in this population is unclear. We sought to summarize current knowledge regarding use of postmenopausal HT and cardiovascular (CV) outcomes, and established surrogate measures of CV risk in women with CKD.

METHODS

This is a systematic review and meta-analysis of adult women with CKD. We searched electronic bibliographic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials) (inception to 2014 December), relevant conference proceedings, tables of contents of journals, and review articles. Randomized controlled trials and observational studies examining postmenopausal HT compared with either placebo or untreated control groups were included. The intervention of interest was postmenopausal HT, and the outcome measures were all-cause and CV mortality, nonfatal CV event (myocardial infarction, stroke), and surrogate measures of CV risk (serum lipids, blood pressure).

RESULTS

Of 12,482 references retrieved, four randomized controlled trials and two cohort studies (N = 1,666 participants) were identified. No studies reported on CV outcomes or mortality. Compared with placebo, postmenopausal HT was associated with decreased low-density lipoprotein cholesterol (-13.2 mg/dL [95% CI, -23.32 to -3.00 mg/dL]), and increased high-density lipoprotein (8.73 mg/dL [95% CI, 4.72-12.73 mg/dL]) and total cholesterol (7.96 mg/dL [95% CI, 0.07-15.84 mg/dL]). No associations were observed between postmenopausal HT triglyceride levels and blood pressure.

CONCLUSIONS

Studies examining the effect of postmenopausal HT on CV outcomes in women with CKD are lacking. Further prospective study of the role of postmenopausal HT in this high-risk group is required.

Hormone Therapy Use and Risk of Chronic Disease in the Nurses' Health Study: A Comparative Analysis With the Women's Health Initiative

Observational studies and randomized controlled trials of menopausal hormone therapy (HT) and chronic disease risk appear to have divergent results for cardiovascular disease. However, differences may be related to a modifying effect of age, time since menopause, and HT formulation. In the Nurses' Health Study (NHS) (enrolling during 1980-1994 and following participants until 2002), we investigated associations between the use of oral conjugated equine estrogens (CEE) (0.625 mg/day) plus medroxyprogesterone acetate (MPA) (<10 mg/day) or oral CEE alone and cardiovascular disease, cancer, all-cause mortality, and other major endpoints among postmenopausal women, aged 50-79 years at HT initiation. Among women aged 50-59 years at HT initiation, associations of CEE alone or CEE+MPA with most clinical outcomes were highly concordant between NHS and Women's Health Initiative (WHI). However, for myocardial infarction, results for CEE+MPA were in the direction of risk elevation in WHI and in the direction of risk reduction in NHS. When examined according to years since menopause onset (<10 years) rather than age group, results were nonsignificant and concordant for both studies. Because few women in the NHS initiated HT after age 60 years, we did not examine associations in this group. Discrepancies between NHS and WHI could largely be attributed to differences in the age structure of the populations and age at HT initiation.

Gender-Related Cardiovascular Risk in Healthy Middle-Aged Adults

Men tend to develop cardiovascular disease (CVD) earlier in life than women. Whether this difference is attributable only to gender is a matter of debate. The purpose of this study was to evaluate gender differences in cardiovascular risk in a large cohort of asymptomatic men and women and explore gender-related risk in prespecified risk factor subgroups. We investigated 14,966 asymptomatic men and women free of diabetes, hypertension, or ischemic heart disease who were annually screened. The primary end point of the present study was the occurrence of ischemic or cerebrovascular disease as composite end point. Multivariate Cox proportional hazards regression modeling was used to assess the gender difference regarding CVD and to examine the association between CVD risk factors and gender. Mean age of the study population was 47 ± 10 years and 30% were women. Kaplan-Meier survival analysis showed that at 6.2 ± 3.9 years' follow-up, the rate of CVD events was 6.1% among men compared with 1.8% among women (log-rank p <0.001). Consistently, multivariate analysis demonstrated that male gender was independently associated with a significant threefold increased risk for development of CVD events (hazard ratio 3.05, CI 2.25 to 4.14). The CVD risk associated with male gender was consistent in each risk subset analyzed, including older age, low high-density lipoprotein, impaired fasting glucose, and positive family history for ischemic heart disease (all p values for gender-by-risk factor interactions <0.05). Higher performance on treadmill test had a protective effect regarding CVD development in both men and women. In conclusions, healthy middle-aged men experienced increased risk for the development of CVD events compared with women independently of traditional CVD risk factors. However, better exercise capacity is associated with a protective effect.

Sex differences in associations between insulin resistance, heart rate variability, and arterial stiffness in healthy women and men: a physiology study

Diabetes confers greater cardiovascular risk to women than to men. Whether insulin-resistance-mediated risk extends to the healthy population is unknown. Measures of insulin resistance (fasting insulin, homeostatic model assessment, hemoglobin A1c, quantitative insulin sensitivity check index, glucose) were determined in 48 (56% female) healthy subjects. Heart rate variability (HRV) was calculated by spectral power analysis and arterial stiffness was determined using noninvasive applanation tonometry. Both were measured at baseline and in response to angiotensin II infusion. In women, there was a non-statistically significant trend towards increasing insulin resistance being associated with an overall unfavourable HRV response and increased arterial stiffness to the stressor, while men demonstrated the opposite response. Significant differences in the associations between insulin resistance and cardiovascular physiological profile exist between healthy women and men. Further studies investigating the sex differences in the pathophysiology of insulin resistance in cardiovascular disease are warranted.

Exogenous Hormone Use: Oral Contraceptives, Postmenopausal Hormone Therapy, and Health Outcomes in the Nurses' Health Study

OBJECTIVES

To review the contribution of the Nurses' Health Study (NHS) to our understanding of the complex relationship between exogenous hormones and health outcomes in women.

METHODS

We performed a narrative review of the publications of the NHS and NHS II from 1976 to 2016.

RESULTS

Oral contraceptive and postmenopausal hormone use were studied in relation to major health outcomes, including cardiovascular disease and cancer. Current or recent oral contraceptive use is associated with a higher risk of cardiovascular disease (mainly among smokers), melanoma, and breast cancer, and a lower risk of colorectal and ovarian cancer. Although hormone therapy is not indicated primarily for chronic disease prevention, findings from the NHS and a recent analysis of the Women's Health Initiative indicate that younger women who are closer to menopause onset have a more favorable risk-benefit profile than do older women from use of hormone therapy for relief of vasomotor symptoms.

CONCLUSIONS

With updated information on hormone use, lifestyle factors, and other variables, the NHS and NHS II continue to contribute to our understanding of the complex relationship between exogenous hormones and health outcomes in women.

Re-adopting classical nuclear receptors by cholesterol metabolites

Since the first cloning of the human estrogen receptor (ER) α in 1986 and the subsequent cloning of human ERβ, there has been extensive investigation of the role of estrogen/ER. Estrogens/ER play important roles not only in sexual development and reproduction but also in a variety of other functions in multiple tissues. Selective Estrogen Receptor Modulators (SERMs) are ER lignds that act as agonists or antagonists depending on the target genes and tissues, and until recently, only synthetic SERMs have been recognized. However, the discovery of the first endogenous SERM, 27-hydroxycholesterol (27HC), opened a new dimension of ER action in health and disease. In addition to the identification of 27HC as a SERM, oxysterols have been recently demonstrated as indirect modulators of ER through interaction with the nuclear receptor Liver X Receptor (LXR) β. In this review, the recent progress on these novel roles of oxysterols in ER modulation is summarized.

Point: incident exposures, prevalent exposures, and causal inference: does limiting studies to persons who are followed from first exposure onward damage epidemiology?

The idea that epidemiologic studies should start from first exposure onward has been advocated in the past few years. The study of incident exposures is contrasted with studies of prevalent exposures in which follow-up may commence after first exposure. The former approach is seen as a hallmark of a good study and necessary for causal inference. We argue that studying incident exposures may be necessary in some situations, but it is not always necessary and is not the preferred option in many instances. Conducting a study involves decisions as to which person-time experience should be included. Although studies of prevalent exposures involve left truncation (missingness on the left), studies of incident exposures may involve right censoring (missingness on the right) and therefore may not be able to assess the long-term effects of exposure. These considerations have consequences for studies of dynamic (open) populations that involve a mixture of prevalent and incident exposures. We argue that studies with prevalent exposures will remain a necessity for epidemiology. The purpose of this paper is to restore the balance between the emphasis on first exposure cohorts and the richness of epidemiologic information obtained when studying prevalent exposures.

Why Ineffective Psychotherapies Appear to Work: A Taxonomy of Causes of Spurious Therapeutic Effectiveness

The past 40 years have generated numerous insights regarding errors in human reasoning. Arguably, clinical practice is the domain of applied psychology in which acknowledging and mitigating these errors is most crucial. We address one such set of errors here, namely, the tendency of some psychologists and other mental health professionals to assume that they can rely on informal clinical observations to infer whether treatments are effective. We delineate four broad, underlying cognitive impediments to accurately evaluating improvement in psychotherapy-naive realism, confirmation bias, illusory causation, and the illusion of control. We then describe 26 causes of spurious therapeutic effectiveness (CSTEs), organized into a taxonomy of three overarching categories: (a) the perception of client change in its actual absence, (b) misinterpretations of actual client change stemming from extratherapeutic factors, and (c) misinterpretations of actual client change stemming from nonspecific treatment factors. These inferential errors can lead clinicians, clients, and researchers to misperceive useless or even harmful psychotherapies as effective. We (a) examine how methodological safeguards help to control for different CSTEs, (b) delineate fruitful directions for research on CSTEs, and (c) consider the implications of CSTEs for everyday clinical practice. An enhanced appreciation of the inferential problems posed by CSTEs may narrow the science-practice gap and foster a heightened appreciation of the need for the methodological safeguards afforded by evidence-based practice.

Assessing potentially time-dependent treatment effect from clinical trials and observational studies for survival data, with applications to the Women's Health Initiative combined hormone therapy trial

For risk and benefit assessment in clinical trials and observational studies with time-to-event data, the Cox model has usually been the model of choice. When the hazards are possibly non-proportional, a piece-wise Cox model over a partition of the time axis may be considered. Here, we propose to analyze clinical trials or observational studies with time-to-event data using a certain semiparametric model. The model allows for a time-dependent treatment effect. It includes the important proportional hazards model as a sub-model and can accommodate various patterns of time-dependence of the hazard ratio. After estimation of the model parameters using a pseudo-likelihood approach, simultaneous confidence intervals for the hazard ratio function are established using a Monte Carlo method to assess the time-varying pattern of the treatment effect. To assess the overall treatment effect, estimated average hazard ratio and its confidence intervals are also obtained. The proposed methods are applied to data from the Women's Health Initiative. To compare the Women's Health Initiative clinical trial and observational study, we use the propensity score in building the regression model. Compared with the piece-wise Cox model, the proposed model yields a better model fit and does not require partitioning of the time axis.

The effect of hormone therapy on all-cause and cardiovascular mortality in women with chronic kidney disease: protocol for a systematic review and meta-analysis

BACKGROUND

Chronic kidney disease affects approximately one in ten North Americans and is associated with a high risk of cardiovascular disease. Chronic kidney disease in women is characterized by an abnormal sex hormone profile and low estradiol levels. Since low estradiol levels are associated with an increased cardiovascular risk in healthy women, our objective is to determine the effect of hormone therapy on all-cause mortality, cardiovascular mortality, and cardiovascular morbidity in women with chronic kidney disease.

METHODS/DESIGN

Studies examining hormone therapy for adult women with chronic kidney disease will be included. The primary outcome is all-cause or cardiovascular mortality and morbidity. We will search electronic bibliographic databases (MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL)) along with relevant conference proceedings, table of contents of journals, and review articles. Two investigators will independently screen identified abstracts and select observational cohort studies, case-control studies, and randomized controlled trials examining hormone therapy in women with chronic kidney disease. These investigators will also independently abstract data from relevant full-text journal articles and assess risk of bias. Where possible, these data will be summarized using pooled or combined estimates for the risk ratio or hazard ratio of all-cause mortality, cardiovascular mortality, and cardiovascular morbidity in women with chronic kidney disease with and without hormone therapy. A random effects model will be used, and meta-regression and subgroup analyses will be used to explore potential source of heterogeneity.

DISCUSSION

Given the high burden of cardiovascular disease in women with chronic kidney disease, this study will help guide clinical practice by summarizing current evidence on the use of hormone therapy for prevention of all-cause mortality, cardiovascular mortality, and cardiovascular morbidity in this population.

SYSTEMATIC REVIEW REGISTRATION

The final protocol was registered with PROSPERO ( CRD42014014566) .

Synthetic gestagens exert differential effects on arterial thrombosis and aortic gene expression in ovariectomized apolipoprotein E-deficient mice

BACKGROUND AND PURPOSE

Combined hormone replacement therapy with oestrogens plus the synthetic progestin medroxyprogesterone acetate (MPA) is associated with an increased risk of thrombosis. However, the mechanisms of this pro-thrombotic effect are largely unknown. The purpose of this study was to: (i) compare the pro-thrombotic effect of MPA with another synthetic progestin, norethisterone acetate (NET-A), (ii) determine if MPA's pro-thrombotic effect can be antagonized by the progesterone and glucocorticoid receptor antagonist mifepristone and (iii) elucidate underlying mechanisms by comparing aortic gene expression after chronic MPA with that after NET-A treatment.

EXPERIMENTAL APPROACH

Female apolipoprotein E-deficient mice were ovariectomized and treated with placebo, MPA, a combination of MPA + mifepristone or NET-A for 90 days on a Western-type diet. Arterial thrombosis was measured in vivo in a photothrombosis model. Aortic gene expression was analysed using microarrays; GeneOntology and KEGG pathway analyses were conducted.

KEY RESULTS

MPA's pro-thrombotic effects were prevented by mifepristone, while NET-A did not affect arterial thrombosis. Aortic gene expression analysis showed, for the first time, that gestagens induce similar effects on a set of genes potentially promoting thrombosis. However, in NET-A-treated mice other genes with potentially anti-thrombotic effects were also affected, which might counterbalance the effects of the pro-thrombotic genes.

CONCLUSIONS AND IMPLICATIONS

The pro-thrombotic effects of synthetic progestins appear to be compound-specific, rather than representing a class effect of gestagens. Furthermore, the different thrombotic responses elicited by MPA and NET-A might be attributed to a more balanced, 'homeostatic' gene expression induced in NET-A- as compared with MPA-treated mice.

Menopausal hormone treatment cardiovascular disease: another look at an unresolved conundrum

Cardiovascular disease (CVD) is the most common cause of death in women. Before the Women's Health Initiative (WHI) hormone trials, evidence favored the concept that menopausal hormone treatment (MHT) protects against CVD. WHI studies failed to demonstrate CVD benefit, with worse net outcomes for MHT versus placebo in the population studied. We review evidence regarding the relationship between MHT and CVD with consideration of mechanisms and risk factors for atherogenesis and cardiac events, results of observational case-control and cohort studies, and outcomes of randomized trials. Estrogen effects on CVD risk factors favor delay or amelioration of atherosclerotic plaque development but may increase risk of acute events when at-risk plaque is present. Long-term observational studies have shown ∼40% reductions in risk of myocardial infarction and all-cause mortality. Analyses of data from randomized control trials other than the WHI show a ∼30% cardioprotective effect in recently menopausal women. Review of the literature as well as WHI data suggests that younger and/or more recently menopausal women may have a better risk-benefit ratio than older or remotely menopausal women and that CVD protection may only occur after >5 years; WHI women averaged 63 years of age (12 years postmenopausal) and few were studied for >6 years. Thus, a beneficial effect of long-term MHT on CVD and mortality is still an open question and is likely to remain controversial for the foreseeable future.

Estrogen and the female heart

Estrogen has a plethora of effects in the cardiovascular system. Studies of estrogen and the heart span human clinical trials and basic cell and molecular investigations. Greater understanding of cell and molecular responses to estrogens can provide further insights into the findings of clinical studies. Differences in expression and cellular/intracellular distribution of the two main receptors, estrogen receptor (ER) α and β, are thought to account for the specificity and differences in responses to estrogen. Much remains to be learned in this area, but cellular distribution within the cardiovascular system is becoming clearer. Identification of GPER as a third ER has introduced further complexity to the system. 17β-estradiol (E2), the most potent human estrogen, clearly has protective properties activating a signaling cascade leading to cellular protection and also influencing expression of the protective heat shock proteins (HSP). E2 protects the heart from ischemic injury in basic studies, but the picture is more involved in the whole organism and clinical studies. Here the complexity of E2's widespread effects comes into play and makes interpretation of findings more challenging. Estrogen loss occurs primarily with aging, but few studies have used aged models despite clear evidence of differences between the response to estrogen deficiency in adult and aged animals. Thus more work is needed focusing on the effects of aging vs. estrogen loss on the cardiovascular system.

Postmenopausal hormone therapy and coronary heart disease in early postmenopausal women

In women, cardiovascular disease (CVD) accounts for about half of all deaths in Western countries. It is generally accepted that endogenous estrogen protects premenopausal women from CVD. However, whether postmenopausal hormone therapy (HT) confers cardiovascular benefit or harm remains controversial. One of the most pronounced factors modifying the cardiovascular effects of HT is age or time since menopause at the initiation of HT. Recently also the impact of hot flushes on CVD risk and the outcomes of HT has gained attention. This review summarizes the newest data regarding HT and CVD in recently postmenopausal women aged 50-59 years in light of the results from older HT trials. The aim is to help clinicians counsel their patients regarding the individual risks and benefits associated with HT use in this age group, where HT use is most prevalent.

Applications of propensity score methods in observational comparative effectiveness and safety research: where have we come and where should we go?

Propensity score (PS) methods have proliferated in recent years in observational studies in general and in observational comparative effectiveness research (CER) in particular. PS methods are an important set of tools for estimating treatment effects in observational studies, enabling adjustment for measured confounders in an easy-to-understand and transparent way. This article demonstrates how PS methods have been used to address specific CER questions from 2001 through to 2012 by identifying six impactful studies from this period. This article also discusses areas for improvement, including data infrastructure, and a unified set of guidelines in terms of PS implementation and reporting, which will boost confidence in evidence generated through observational CER using PS methods.

An analytic framework for aligning observational and randomized trial data: Application to postmenopausal hormone therapy and coronary heart disease

We describe a conceptual analytic framework for aligning observational and randomized controlled trial (RCT) data. The framework allows one to 1) use observational data to estimate treatment effects comparable to their RCT counterparts, 2) properly include early events that occur soon after treatment initiation in the analysis of observational data, 3) estimate various treatment effects that are of clinical and scientific relevance while appropriately adjusting for time-varying confounders in both the RCT and observational analyses, 4) assess the generalizability of RCT findings in the more diverse populations generally found in the observational data, and 5) combine both types of data to study associations that cannot be addressed by one study or a single dataset. We describe the theoretical application of this framework to the Women's Health Initiative data to examine the relation between postmenopausal hormone therapy and coronary heart disease. The analytic framework can be tailored to specific exposure-outcome associations and data sources, and may be refined as more is learned about its strengths and limitations.

Postmenopausal hormone therapy is not associated with risk of all-cause dementia and Alzheimer's disease

The relationship of postmenopausal hormone therapy with all-cause dementia and Alzheimer's disease dementia has been controversial. Given continued interest in the role of hormone therapy in chronic disease prevention and the emergence of more prospective studies, we conducted a systematic review to identify all epidemiologic studies meeting prespecified criteria reporting on postmenopausal hormone therapy use and risk of Alzheimer's disease or dementia. A systematic search of Medline and Embase through December 31, 2012, returned 15 articles meeting our criteria. Our meta-analysis of any versus never use did not support the hypothesis that hormone therapy reduces risk of Alzheimer's disease (summary estimate = 0.88, 95% confidence interval: 0.66, 1.16). Exclusion of trial findings did not change this estimate. There were not enough all-cause dementia results for a separate meta-analysis, but when we combined all-cause dementia results (n = 3) with Alzheimer's disease results (n = 7), the summary estimate remained null (summary estimate = 0.94, 95% confidence interval: 0.71, 1.26). The limited explorations of timing of use-both duration and early initiation-did not yield consistent findings. Our findings support current recommendations that hormone therapy should not be used for dementia prevention. We discuss trends in hormone therapy research that could explain our novel findings and highlight areas where additional data are needed.

Timing hypothesis for postmenopausal hormone therapy: its origin, current status, and future

OBJECTIVE

This work aims to review preclinical/clinical cardiovascular studies that led to randomized trials of the risks and benefits of postmenopausal hormone therapy (HT), the pathobiological basis for the timing hypothesis, and subset analyses of randomized trials that tend to support the timing hypothesis; to elaborate experimental data that might inform the results of recent trials; and to summarize evidence regarding how early is early enough for the initiation of HT.

METHODS

This work used interpretive literature review.

RESULTS

Preclinical and large observational studies provided what was considered at the time to be convincing evidence that HT provided protection against progressing coronary artery atherosclerosis. Those findings prompted three randomized, placebo-controlled, prospective trials to determine the risks and benefits of HT. None provided any evidence that HT had any beneficial effects on preexisting coronary artery atherosclerosis. Monkey studies provided clear evidence that HT was effective in slowing the progression of coronary artery atherosclerosis only when administered soon after surgical menopause and that benefit was lost if estrogen therapy was delayed until the plaques had become complicated. The phenomenon was referred to as the "timing hypothesis," and evidence for its translation into postmenopausal women was sought in subset analyses of data from the Women's Health Initiative and from newly planned prospective trials.

CONCLUSIONS

Current data are both supportive and not supportive of the timing hypothesis. However, evidence indicating that estrogens administered in the perimenopausal transition or early in menopause are not harmful to the cardiovascular system and, when given for a few years for the treatment of menopausal symptoms, may slow the progression of atherosclerosis and reduce the postmenopausal cardiovascular disease burden seems convincing.

Estrogen therapy, independent of timing, improves cardiac structure and function in oophorectomized mRen2.Lewis rats

OBJECTIVE

mRen2.Lewis rats exhibit exacerbated increases in blood pressure, left ventricular (LV) remodeling, and diastolic impairment after the loss of estrogens. In this same model, depletion of estrogens has marked effects on the cardiac biopterin profile concomitant with suppressed nitric oxide release. With respect to the establishment of overt systolic hypertension after oophorectomy (OVX), we assessed the effects of timing long-term 17β-estradiol (E2) therapy on myocardial function, myocardial structure, and the cardiac nitric oxide system.

METHODS

OVX (n = 24) or sham operation (Sham; n = 13) was performed in 4-week-old female mRen2.Lewis rats. After randomization, OVX rats received E2 immediately (OVX + E2-early; n = 7), E2 at 11 weeks of age (OVX + E2-late; n = 8), or no E2 at all (OVX; n = 9).

RESULTS

E2-early was associated with lower body weight, less hypertension-related cardiac remodeling, and decreased LV filling pressure compared with OVX rats without E2 supplementation. E2-late similarly attenuated the adverse effects of ovarian hormone loss on tissue Doppler-derived LV filling pressures and perivascular fibrosis, and significantly improved myocardial relaxation or mitral annular velocity (e'). Early and late exposures to E2 decreased dihydrobiopterin, but only E2-late yielded significant increases in cardiac nitrite concentrations.

CONCLUSIONS

Although there are some similarities between E2-early and E2-late treatments in relation to preservation of diastolic function and cardiac structure after OVX, the lusitropic potential of E2 is most consistent with late supplementation. The cardioprotective effects of E2-late are independent of blood pressure and may have occurred through regulation of cardiac biopterins and nitric oxide production.

The role of personalized medicine in identifying appropriate candidates for menopausal estrogen therapy

Menopausal estrogen therapy has a complex balance of benefits and risks and is no longer routinely recommended for the majority of women during or after the transition to menopause. Recent findings from the Women's Health Initiative (WHI) and other studies suggest that a woman's clinical and biological characteristics may modify her health outcomes on hormone therapy (HT) and that some women may be more appropriate candidates for therapy than others. An emerging body of evidence suggests that it may be possible to identify women who are more likely to have favorable outcomes and less likely to have adverse events on HT, as well as to tailor the optimal dose, formulation, and route of delivery of treatment, by the use of individual risk stratification and a personalized approach. Several clinical characteristics that have been proposed for this purpose include a woman's age, time since menopause, symptom severity, baseline vascular health, risk for breast cancer, biomarker levels, and genetic predisposition. The underlying rationale for personalized medicine, that each person has a unique biologic profile that can help to guide the choice of therapy, applies well to HT decision making and holds promise for improved treatment efficacy and safety. This report, which focuses on vascular health, reviews the evidence on the role of such markers in tailoring the use of hormone therapy to appropriate candidates, with the ultimate goal of developing a personalized risk:benefit prediction model that takes into account clinical and genetic factors, "patient-centered" outcomes including sense of well being and quality of life, and other variables. The proposed personalized approach to HT decision making has the potential to improve the quality of health care.

Relationships of coronary heart disease with 27-hydroxycholesterol, low-density lipoprotein cholesterol, and menopausal hormone therapy

BACKGROUND

Menopausal hormone therapy (MHT) increases the risk of coronary heart disease (CHD) in older women with elevated low-density lipoprotein (LDLC) levels. The endogenous estrogen receptor antagonist 27-hydroxycholesterol (27OHC) is correlated with LDLC levels and may block the beneficial effects of estrogen on the cardiovascular system.

METHODS AND RESULTS

We conducted a nested case-control study in the Women's Health Initiative trials of 350 CHD cases and 813 matched controls to explore potential mediation by 27OHC of the dependence of the CHD risk elevation with MHT on LDLC. Baseline levels of 27OHC were not associated with CHD risk when LDLC was included in the multivariable models. The odds ratio for CHD associated with increased LDLC was 1.15 (95% confidence interval, 1.08-1.23) and was unchanged at 1.14 (95% confidence interval, 1.07-1.22) when 27OHC was added to the model. Baseline 27OHC did not interact with MHT on CHD risk (P=0.81). In contrast, LDLC levels modified the effect of MHT on CHD risk (P for interaction=0.02), and adding 27OHC did not affect this result. With the use of log scales, the effect of MHT on CHD increased linearly with increasing level of baseline LDLC, with a transition from no risk to increased risk at ≈3.36 mmol/L (130 mg/dL).

CONCLUSIONS

This study found that 27OHC does not independently increase the risk of CHD, does not modify the increased risk of CHD resulting from MHT, and does not mediate the interaction of LDLC with MHT. Measuring blood lipids may aid in counseling individual women about initiating MHT and cardiovascular risk mitigation.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000611.

Sex and atopy influences on the natural history of rhinitis

PURPOSE OF REVIEW

Rhinitis is a common condition associated with significant under-recognized morbidity and impaired quality of life. The natural history of rhinitis is poorly characterized. Better understanding of its natural history and associated risk factors would improve the ability to effectively manage rhinitis in clinical practice. This review focuses on the current research findings on the natural history of rhinitis and how that is influenced by atopy and sex.

RECENT FINDINGS

Recent work from the Isle of Wight Birth Cohort Study has demonstrated that the prevalence of atopic rhinitis increases steadily in the first 18 years of life in both sexes. However, nonatopic rhinitis behaves differently during adolescence. Its prevalence decreases in boys but continues to increase in girls resulting in a female predominance after puberty. Numerous recent studies have proposed potential roles for sex-related and adipose-related hormonal changes in influencing the course of allergic disease. Further research is needed to establish mechanisms that could underlie such findings.

SUMMARY

Rhinitis becomes increasingly common through childhood, with prevalence during adolescence being mediated by differential effects of sex and atopy. Mechanisms to explain these findings await elucidation.