Sex differences in the effectiveness of statins after myocardial infarction

Simvastatin and dehydroepiandrosterone sulfate effects against hypoxic pulmonary hypertension are not additive

Pulmonary hypertension is a group of disorders characterized by elevated mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance. To test our hypothesis that combining two drugs useful in experimental pulmonary hypertension, statins and dehydroepiandrosterone sulfate (DHEA S), is more effective than either agent alone, we induced pulmonary hypertension in adult male rats by exposing them to hypoxia (10%O2) for 3 weeks. We treated them with simvastatin (60 mg/l) and DHEA S (100 mg/l) in drinking water, either alone or in combination. Both simvastatin and DHEA S reduced mPAP (froma mean±s.d. of 34.4±4.4 to 27.6±5.9 and 26.7±4.8 mmHg, respectively), yet their combination was not more effective (26.7±7.9 mmHg). Differences in the degree of oxidative stress (indicated by malondialdehydeplasma concentration),the rate of superoxide production (electron paramagnetic resonance), or blood nitric oxide levels (chemiluminescence) did not explain the lack of additivity of the effect of DHEA S and simvastatin on pulmonary hypertension. We propose that the main mechanism of both drugs on pulmonary hypertension could be their inhibitory effect on 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, which could explain their lack of additivity.

Simvastatin and dehydroepiandrosterone sulfate effects against hypoxic pulmonary hypertension are not additive

Pulmonary hypertension is a group of disorders characterized by elevated mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance. To test our hypothesis that combining two drugs useful in experimental pulmonary hypertension, statins and dehydroepiandrosterone sulfate (DHEA S), is more effective than either agent alone, we induced pulmonary hypertension in adult male rats by exposing them to hypoxia (10%O2) for 3 weeks. We treated them with simvastatin (60 mg/l) and DHEA S (100 mg/l) in drinking water, either alone or in combination. Both simvastatin and DHEA S reduced mPAP (froma mean±s.d. of 34.4±4.4 to 27.6±5.9 and 26.7±4.8 mmHg, respectively), yet their combination was not more effective (26.7±7.9 mmHg). Differences in the degree of oxidative stress (indicated by malondialdehydeplasma concentration),the rate of superoxide production (electron paramagnetic resonance), or blood nitric oxide levels (chemiluminescence) did not explain the lack of additivity of the effect of DHEA S and simvastatin on pulmonary hypertension. We propose that the main mechanism of both drugs on pulmonary hypertension could be their inhibitory effect on 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, which could explain their lack of additivity.

Sex Difference in Control of Low-Density Lipoprotein Cholesterol in Older Patients after Acute Coronary Syndrome

Objective. The main aim of this study is to examine the achievement of low-density lipoprotein cholesterol (LDL-C) targets in older patients after acute coronary syndrome (ACS), and the secondary aim is to examine sex difference in LDL-C target achievement. Methods. Patients aged ≥60 years with ACS admitted to a tertiary hospital in Vietnam were recruited from December 2019 to August 2020. LDL-C target achievement was defined as having an LDL-C goal of <1.8 mmol/L. Multivariate logistic regression was applied to investigate the predictive factors for LDL-C target achievement. Results. A total of 232 participants were included in this study (mean age 75.5 years, 40.1% were women). Participants had an average of three chronic conditions other than coronary heart disease. All participants were prescribed statin monotherapy at discharge (59.5% on high-intensity statins). After 3 months, 218 (94.0%) of the participants were on statin monotherapy, 14 (6.0%) were on statin combined with ezetimibe. The proportion of participants that achieved LDL-C target after 3 months was 56.5% (40.9% in women and 66.9% in men, p < 0.001). On univariate logistic regression, women were less likely to achieve their LDL-C target compared to men (unadjusted OR 0.34, 95% CI 0.20−0.59). This association was still significant in the adjusted model (adjusted OR 0.43, 95% CI 0.24−0.78). Other factors that were significantly associated with LDL-C target achievement included age, smoking, sedentary lifestyle, LDL-C level on admission, history of using statin before admission, and high-intensity statin prescribed at discharge. Conclusions. Our study found that nearly a half of older patients with ACS did not achieve their LDL-C target after 3 months, and suboptimal control of LDL-C was more common in women.

Sex-Specific Associations Between Serum Lipids, Antinuclear Antibodies, and Statin Use in National Health and Nutrition Examination Surveys 1999-2004

Lipid metabolism contributes to the regulation of leukocyte activity and immune responses, and may serve as a therapeutic target in the pathophysiology and clinical management of autoimmune disorders. In addition to lipid-lowering properties, statins have been shown to exert anti-inflammatory and immunomodulatory effects within the context of autoimmunity. Importantly, autoimmune incidence and lipid markers differ between men and women, suggesting that the relationship between lipid metabolism and immune function may vary by sex. Therefore, we investigated whether a predictive, sex-specific relationship exists between serum lipids, statin use, and antinuclear antibodies (ANA)—a routine clinical marker of autoimmunity and immune dysfunction—in U.S. men and women (>20 years old; n = 1,526) from the National Health and Nutrition Examination Survey (NHANES) 1999–2004. Within this population, a greater proportion of women were positive for ANA (ANA+) and had higher ANA titers, as compared to men. While we did not observe statistical differences in average total cholesterol, LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), or triglyceride levels in ANA positive (ANA+) vs. ANA negative (ANA–) men or women, we observed that a greater proportion of ANA+ women had high total cholesterol levels (>240 mg/dL) when compared to ANA+ men (13.0 vs. 9.0%), and that a greater percentage of ANA+ women had low HDL-C as compared to ANA+ men (29.2 vs. 19.6%). However, in logistic regression models, total cholesterol, LDL-C, and HDL-C levels were not able to predict ANA status, whereas elevated serum triglycerides (150 to < 200 mg/dL) were significantly less likely to be ANA+ vs. ANA– (OR 0.33; 95% CI 0.11–0.92) in men only. Interestingly, women who reported taking statins have significantly lower odds of being ANA+ (OR 0.25; 95% CI 0.09–0.76), whereas no significant association between statin use and ANA status was observed in men. Together, our findings provide novel insight into the relationship between lipid metabolism and autoimmunity by elucidating the limited, albeit sex-specific utility of routine clinical serum lipid levels to predict ANA status at the population level, while further identifying a sex-specific and protective role for statins in predicting ANA status in women.

Sex disparities in the effect of statins on lipid parameters: The PharmLines Initiative

Real-world evidence on a potential statin effect modification by sex is inconclusive, especially for the primary prevention of cardiovascular disease (CVD). We aimed to quantify the differences in the effect of statins on lipid parameters between men and women.The PharmLines Initiative linked the Lifelines Cohort Study and the IADB.nl prescription database. This database covers a representative population from the Netherlands. We selected participants aged ≥40 years at the index date: the date of the first prescription of any statin monotherapy in the study period 2006 to 2017. Multivariate regression modeling was used to compare the difference of the mean percentage change of lipid parameters (% mean difference [MD]) from baseline to follow-up measurement between the sexes.Out of 5366 statin users from approximately 50,000 participants available in the final linked database, 685 were statin initiators. At baseline, women had significantly higher levels of mean total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) than men (all P values <.01). At follow-up, women had a significantly higher mean percentage change of HDL-C compared to men (adjusted % MD 5.59, 95% confidence interval [CI] 2.42-8.75, P < .01). There was no significant sex difference in other parameters, nor in the proportion of men and women who achieved LDL-C ≤2.5 mmol/L.Statins appear to have a greater effect on increasing HDL-C levels in women than men while showing similar effect on other lipid parameters in both sexes. Men should not be treated differently than women.

Increasing likelihood of prescribing recommended lipid management: Primary care providers' participation in cardiology continuing medical education

OBJECTIVE

To explore whether participation in a series of cardiology continuing medical education (CME) activities affects primary care providers' (PCPs') lipid management for their patients.

DESIGN

This retrospective cohort study used a database of participation in cardiology CME activities (2011 to 2017) linked to electronic medical records. Statistical analyses were completed using logistic regression with generalized estimating equations.

SETTING

Manitoba.

PARTICIPANTS

Patients receiving care from 225 PCPs participating in the Manitoba Primary Care Research Network.

MAIN OUTCOME MEASURES

Recommended lipid management was defined as prescription of statins (yes or no) among patients diagnosed with cardiovascular disease (CVD), patients diagnosed with diabetes mellitus (DM; 40 years or older), and patients diagnosed with chronic kidney disease (CKD; 50 years and older) in 2017. Treatment was identified using the ATC (Anatomical Therapeutic Chemical) system (ATC code C10AA or C10B).

RESULTS

After adjusting for relevant confounders, the odds of prescribing statins to patients with CVD, DM, or CKD among PCPs who did not participate in the cardiology CME activities were 50%, 55%, and 67% lower, respectively, than among PCPs who participated in 2 or more activities. The odds of prescribing statins to patients with CVD and DM among PCPs who participated in only 1 cardiology CME activity were also 67% and 63% lower, respectively, than among PCPs who participated in 2 or more activities.

CONCLUSION

Results suggested that PCPs who participated in 2 or more cardiology CME activities were more likely to prescribe recommended lipid management (statins) for adults with CVD, DM, or CKD.

Sex disparities and adverse cardiovascular and kidney outcomes in patients with chronic kidney disease: results from the KNOW-CKD

AIMS

Longitudinal studies of the association between sex and adverse clinical outcomes in patients with chronic kidney disease (CKD) are scarce. We assessed whether major outcomes may differ by sex among CKD patients.

METHODS

We analyzed a total of 1780 participants with non-dialysis CKD G1-5 from the KoreaN cohort study for Outcome in patients with Chronic Kidney Disease (KNOW-CKD). The primary outcome was a composite of non-fatal cardiovascular events or all-cause mortality. Secondary outcomes included fatal and non-fatal cardiovascular events, all-cause mortality, and a composite kidney outcome of ≥ 50% decline in estimated glomerular filtration rate from baseline or the onset of end-stage kidney disease.

RESULTS

There were 1088 (61%) men and 692 (39%) women in the study cohort. The proportion of smokers was significantly higher in men (24% vs. 3%). During 8430 person-years of follow-up, 201 primary outcome events occurred: 144 (13%) in men and 57 (8%) in women, with corresponding incidence rates of 2.9 and 1.7 per 100 person-years, respectively. In multivariable Cox models, men were associated with a 1.58-fold (95% CI 1.06-2.35) higher risk of composite outcome. Propensity score matching analysis revealed similar findings (HR 1.81; 95% CI 1.14-2.91). Risk of all-cause mortality was significantly higher in men of the matched cohort. However, there was no difference in the risk of CKD progression. In the subgroup with coronary artery calcium (CAC) measurements, men had a higher likelihood of CAC progression.

CONCLUSIONS

In Korean CKD patients, men were more likely to experience adverse cardiovascular events and death than women.

Impact of Statin Use on Dementia Incidence in Elderly Men and Women with Ischemic Heart Disease

This study aimed to determine the association between statins and the prevention of dementia according to sex differences in elderly patients with ischemic heart disease (IHD). We performed a nationwide retrospective cohort study using the Korean Health Insurance Review and Assessment Service database (2007–2015). Among the 264,036 eligible patients aged ≥65 years with IHD, statin users were compared with non–users by propensity score matching at a 1:1 ratio (71,587 in each group). The primary outcome was dementia risk by estimating hazard ratios (HRs) and 95% confidence intervals (CIs). Differential risks of dementia were assessed by sex in the subgroups of statin types, exposure duration, and patient age, implying that sex is an influential factor for the link between statin use and dementia incidence. Among seven commonly prescribed statins, rosuvastatin was associated with the greatest preventive effect on dementia incidence, with an adjusted HR of 0.82 (95% CI = 0.78–0.87). In a subgroup analysis organized by sex, the differential risk of dementia incidence was assessed in each statin group, implying that sex is an influential factor for the link between statin and dementia. This study suggests that appropriate statin use considering sex differences may have beneficial effects on the development of dementia.

Cardiovascular Risks Associated with Gender and Aging

The aging and elderly population are particularly susceptible to cardiovascular disease. Age is an independent risk factor for cardiovascular disease (CVD) in adults, but these risks are compounded by additional factors, including frailty, obesity, and diabetes. These factors are known to complicate and enhance cardiac risk factors that are associated with the onset of advanced age. Sex is another potential risk factor in aging adults, given that older females are reported to be at a greater risk for CVD than age-matched men. However, in both men and women, the risks associated with CVD increase with age, and these correspond to an overall decline in sex hormones, primarily of estrogen and testosterone. Despite this, hormone replacement therapies are largely shown to not improve outcomes in older patients and may also increase the risks of cardiac events in older adults. This review discusses current findings regarding the impacts of age and gender on heart disease.

Sex-Interacting mRNA- and miRNA-eQTLs and Their Implications in Gene Expression Regulation and Disease

Despite sex being an important epidemiological and physiological factor, not much is known about how sex works to interact with genotypes to result in different phenotypes. Both messenger RNA (mRNA) and microRNA (miRNA) may be differentially expressed between the sexes in different physiological conditions, and both may be differentially regulated between males and females. Using whole transcriptome data on lymphoblastoid cell lines from 338 samples of European origin, we tried to uncover genes differentially expressed between the two sexes and sex-interacting expression quantitative trait loci (ss-eQTLs). Two miRNAs were found to be differentially expressed between the two sexes, both of which were found to be functionally implicated in breast cancer. Using two stage linear regression analysis, 21 mRNA ss-eQTL and 3 miRNA ss-eQTLs were discovered. We replicated two of the mRNA ss-eQTLs (p < 0.1) using a separate dataset of gene expression data derived from monocytes. Three mRNA ss-eQTLs are in high linkage disequilibrium with variants also found to be associated with sexually dimorphic traits. Taken together, we believe the ss-eQTLs presented will assist researchers in uncovering the basis of sex-biased gene expression regulation, and ultimately help us understand the genetic basis of differences in phenotypes between sexes.

Gender Dictates the Relationship between Serum Lipids and Leukocyte Counts in the National Health and Nutrition Examination Survey 1999⁻2004

Dyslipidemias and leukocytosis are associated with cardiovascular disease and immune disorders. Mechanistic studies have shown lipoprotein metabolism to play a significant role in the regulation of atherosclerosis development and leukocyte activation, whereas lipid-lowering treatments have been shown to exert beneficial anti-inflammatory and immunomodulatory effects in clinical trials. However, the relationship between clinical markers of lipid metabolism and leukocyte counts has not been extensively evaluated at the population level. We aimed to determine whether clinical blood lipid measures are associated with leukocyte counts in the general U.S. population represented in the National Health and Nutrition Examination Survey (NHANES) 1999–2004, and whether differences exist between men and women (n = 5647). We observed a strong positive linear trend between serum triglycerides vs. blood lymphocyte and basophil counts in both men and women, whereas a positive trend between monocytes vs. triglycerides and lymphocytes vs. total cholesterol and LDL-cholesterol (LDL-C) was only detected in women. Conversely, HDL-C was inversely associated with a greater number of leukocyte subsets in men, whereas inverse trends between HDL-C vs. lymphocytes were observed in both men and women. In multiple regression models, a 10% increase in total cholesterol, LDL-C, and triglycerides was associated with a predicted 1.6%, 0.6%, and 1.4% increase in blood lymphocyte counts in women, respectively, whereas no relationship was observed in men. In both men and women, a 10% increase in triglycerides was additionally associated with higher lymphocyte, neutrophil, and basophil counts, whereas 10% increases in HDL-cholesterol were associated with significantly lower lymphocyte, neutrophil, eosinophil, and basophil counts in men, in addition to lower lymphocyte and monocyte counts in women. These findings suggest that clinical lipid markers may be used to predict blood leukocyte distributions, and that a gender-specific relationship exists between distinct classes of serum lipids and immune cell subsets.

Gender in Endocrine Diseases: Role of Sex Gonadal Hormones

Gender- and sex- related differences represent a new frontier towards patient-tailored medicine, taking into account that theoretically every medical specialty can be influenced by both of them. Sex hormones define the differences between males and females, and the different endocrine environment promoted by estrogens, progesterone, testosterone, and their precursors might influence both human physiology and pathophysiology. With the term Gender we refer, instead, to behaviors, roles, expectations, and activities carried out by the individual in society. In other words, "gender" refers to a sociocultural sphere of the individual, whereas "sex" only defines the biological sex. In the last decade, increasing attention has been paid to understand the influence that gender can have on both the human physiology and pathogenesis of diseases. Even the clinical response to therapy may be influenced by sex hormones and gender, but further research is needed to investigate and clarify how they can affect the human pathophysiology. The path to a tailored medicine in which every patient is able to receive early diagnosis, risk assessments, and optimal treatments cannot exclude the importance of gender. In this review, we have focused our attention on the involvement of sex hormones and gender on different endocrine diseases.

Differences Between Women and Men in Phase I Cardiac Rehabilitation After Acute Myocardial Infarction: A Nationwide Population-Based Analysis

Although numerous studies have investigated gender-related differences in patients who have had an acute myocardial infarction (AMI), few studies have examined the gender-related differences among inpatients receiving Phase I inpatient cardiac rehabilitation following AMI.Using data from the Taiwan National Health Insurance Research Database, this study analyzed 6713 adult patients who received inpatient cardiac rehabilitation following AMI between 2002 and 2011. The differences in comorbidity, medical service use, and prognosis between the male and female patients were analyzed to determine whether the comorbidities affecting their prognoses differed.Female patients accounted for 23.18% of the sample, had a higher average age, and exhibited severe comorbidities; furthermore, they had significantly more days of hospitalization and days in an intensive care unit than did male patients. The gender-related differences in hospital mortality rate and 30-day mortality rate were nonsignificant, but female patients exhibited a significantly higher 1-year mortality rate. Moreover, the risk for 1-year mortality was higher among female patients with moderate or severe renal disease (odds ratio: 1.94, 95% confidence interval: 1.29-2.92) than among their male counterparts. However, the 1-year mortality rate for the female patients did not increase after all risk factors were adjusted.Gender-related differences in age, comorbidity, and prognosis were confirmed in AMI patients receiving Phase I inpatient cardiac rehabilitation. In addition, gender-related differences were observed in the comorbidity risk factors affecting prognosis. However, being female did not affect the prognosis.

Sex differences in long-term mortality after myocardial infarction: a systematic review

BACKGROUND

Studies of sex differences in long-term mortality after acute myocardial infarction have reported mixed results. A systematic review is needed to characterize what is known about sex differences in long-term outcomes and to define gaps in knowledge.

METHODS AND RESULTS

We searched the Medline database from 1966 to December 2012 to identify all studies that provided sex-based comparisons of mortality after acute myocardial infarction. Only studies with at least 5 years of follow-up were reviewed. Of the 1877 identified abstracts, 52 studies met the inclusion criteria, of which 39 were included in this review. Most studies included fewer than one-third women. There was significant heterogeneity across studies in patient populations, methodology, and risk adjustment, which produced substantial variability in risk estimates. In general, most studies reported higher unadjusted mortality for women compared with men at both 5 and 10 years after acute myocardial infarction; however, many of the differences in mortality became attenuated after adjustment for age. Multivariable models varied between studies; however, most reported a further reduction in sex differences after adjustment for covariates other than age. Few studies examined sex-by-age interactions; however, several studies reported interactions between sex and treatment whereby women have similar mortality risk as men after revascularization.

CONCLUSIONS

Sex differences in long-term mortality after acute myocardial infarction are largely explained by differences in age, comorbidities, and treatment use between women and men. Future research should aim to clarify how these differences in risk factors and presentation contribute to the sex gap in mortality.

Quality of cardiovascular disease care in Ontario's primary care practices: a cross sectional study examining differences in guideline adherence by patient sex

Background

Women are disproportionately affected by cardiovascular disease, often experiencing poorer outcomes following a cardiovascular event. Evidence points to inequities in processes of care as a potential contributing factor. This study sought to determine whether any sex differences exist in adherence to process of care guidelines for cardiovascular disease within primary care practices in Ontario, Canada.

Methods

This is a secondary analysis of pooled cross-sectional baseline data collected through a larger quality improvement initiative known as the Improved Delivery of Cardiovascular Care (IDOCC). Chart abstraction was performed for 4,931 patients from 84 primary care practices in Eastern Ontario who had, or were at high risk of, cardiovascular disease. Measures examining adherence to guidelines associated with nine areas of cardiovascular care (coronary artery disease, peripheral vascular disease (PVD), stroke/transient ischemic attack, chronic kidney disease, diabetes, dyslipidemia, hypertension, smoking cessation, and weight management) were collected. Multivariable logistic regression analysis was performed to evaluate sex differences, adjusting for age, physician remuneration, and rurality.

Results

Women were significantly less likely to have their lipid profiles taken (OR = 1.17, 95% CI 1.03-1.33), be prescribed lipid lowering medication for dyslipidemia (OR = 1.54, 95% CI 1.20-1.97), and to be prescribed ASA following stroke (OR = 1.56, 95% CI 1.39-1.75). Women with PVD were significantly less likely to be prescribed ACE inhibitors and/or angiotensin receptor blockers (OR = 1.74, 95% CI 1.25-2.41) and lipid lowering medications (OR = 1.95, 95% CI 1.46-2.62) or ASA (OR = 1.59, 95% CI 1.43-1.78). However, women were more likely to have two blood pressure measurements taken and to be referred to a dietician or weight loss program. Male patients with diabetes were less likely to be prescribed glycemic control medication (OR = 0.84, 95% CI 0.74-0.86).

Conclusions

Sex disparities exist in the quality of cardiovascular care in Canadian primary care practices, which tend to favour men. Women with PVD have a particularly high risk of not receiving appropriate medications. Our findings indicate that improvements in care delivery should be made to address these issues, particularly with regard to the prescribing of recommended medications for women, and preventive measures for men.

Sex disparities in the quality of diabetes care: biological and cultural factors may play a different role for different outcomes: a cross-sectional observational study from the AMD Annals initiative

OBJECTIVE

To investigate the quality of type 2 diabetes care according to sex.

RESEARCH DESIGN AND METHODS

Clinical data collected during the year 2009 were extracted from electronic medical records; quality-of-care indicators were evaluated. Multilevel logistic regression analysis was applied to estimate the likelihood of women versus men to be monitored for selected parameters, to reach clinical outcomes, and to be treated with specific classes of drugs. The intercenter variability in the proportion of men and women achieving the targets was also investigated.

RESULTS

Overall, 415,294 patients from 236 diabetes outpatient centers were evaluated, of whom 188,125 (45.3%) were women and 227,169 (54.7%) were men. Women were 14% more likely than men to have HbA1c>9.0% in spite of insulin treatment (odds ratio 1.14 [95% CI 1.10-1.17]), 42% more likely to have LDL cholesterol (LDL-C)≥130 mg/dL (1.42 [1.38-1.46]) in spite of lipid-lowering treatment, and 50% more likely to have BMI≥30 kg/m2 (1.50 [1.50-1.54]). Women were less likely to be monitored for foot and eye complications. In 99% of centers, the percentage of men reaching the LDL-C target was higher than in women, the proportion of patients reaching the HbA1c target was in favor of men in 80% of the centers, and no differences emerged for blood pressure.

CONCLUSIONS

Women show a poorer quality of diabetes care than men. The attainment of the LDL-C target seems to be mainly related to pathophysiological factors, whereas patient and physician attitudes can play an important role in other process measures and outcomes.

Presentation, management, and outcomes of ischaemic heart disease in women

Scientific interest in ischaemic heart disease (IHD) in women has grown considerably over the past 2 decades. A substantial amount of the literature on this subject is centred on sex differences in clinical aspects of IHD. Many reports have documented sex-related differences in presentation, risk profiles, and outcomes among patients with IHD, particularly acute myocardial infarction. Such differences have often been attributed to inequalities between men and women in the referral and treatment of IHD, but data are insufficient to support this assessment. The determinants of sex differences in presentation are unclear, and few clues are available as to why young, premenopausal women paradoxically have a greater incidence of adverse outcomes after acute myocardial infarction than men, despite having less-severe coronary artery disease. Although differential treatment on the basis of patient sex continues to be described, the extent to which such inequalities persist and whether they reflect true disparity is unclear. Additionally, much uncertainty surrounds possible sex-related differences in response to cardiovascular therapies, partly because of a persistent lack of female-specific data from cardiovascular clinical trials. In this Review, we assess the evidence for sex-related differences in the clinical presentation, treatment, and outcome of IHD, and identify gaps in the literature that need to be addressed in future research efforts.

Bias in observational studies of prevalent users: lessons for comparative effectiveness research from a meta-analysis of statins

Randomized clinical trials (RCTs) are usually the preferred strategy with which to generate evidence of comparative effectiveness, but conducting an RCT is not always feasible. Though observational studies and RCTs often provide comparable estimates, the questioning of observational analyses has recently intensified because of randomized-observational discrepancies regarding the effect of postmenopausal hormone replacement therapy on coronary heart disease. Reanalyses of observational data that excluded prevalent users of hormone replacement therapy led to attenuated discrepancies, which begs the question of whether exclusion of prevalent users should be generally recommended. In the current study, the authors evaluated the effect of excluding prevalent users of statins in a meta-analysis of observational studies of persons with cardiovascular disease. The pooled, multivariate-adjusted mortality hazard ratio for statin use was 0.77 (95% confidence interval (CI): 0.65, 0.91) in 4 studies that compared incident users with nonusers, 0.70 (95% CI: 0.64, 0.78) in 13 studies that compared a combination of prevalent and incident users with nonusers, and 0.54 (95% CI: 0.45, 0.66) in 13 studies that compared prevalent users with nonusers. The corresponding hazard ratio from 18 RCTs was 0.84 (95% CI: 0.77, 0.91). It appears that the greater the proportion of prevalent statin users in observational studies, the larger the discrepancy between observational and randomized estimates.

Breakout session: Gender and ethnic disparities in pain management

BACKGROUND

Pain management is a complex and evolving topic. Treatment of pain must account for biochemical as well as social and economic factors. Sex, gender, and ethnic differences exist in the pathophysiology, diagnosis, and provision of care for patients with pain.

QUESTIONS/PURPOSES

We sought to identify the sex, gender, and ethnic disparities leading to care inequalities with respect to pain management. Our purposes were to (1) clarify the state of where we are now, (2) outline ways to approach where we need to go, and (3) generate solutions for how we get there. WHERE ARE WE NOW?: Studies are beginning to uncover the biologic mechanisms underlying the pain response in sex, gender, and ethnic subgroups. Patient characteristics that increase the risk of postoperative pain are being identified. WHERE DO WE NEED TO GO?: Much work needs to be done in medical education with respect to sex, gender, and ethnic disparities in pain management. Research efforts must better describe differences in physiology of pain, incidence of pain, coping strategies, patient-doctor relationships, and gender/ethnic-specific modes of care for the patient with pain. HOW DO WE GET THERE?: Future work will involve combined efforts with pain/anesthesia specialty societies, developing a disparities and pain management curriculum for medical providers, endorsing health literacy, performing high-quality Level I/II research, and exploring systems processes in pain management in the acute hospital setting.

2-methoxyestradiol inhibits atorvastatin-induced rounding of human vascular smooth muscle cells

The cardiovascular benefits of statins, including atorvastatin (ATV), have been reported to be gender-dependent, but the underlying mechanism is unclear. In this study we examine whether estrogen and its metabolite, 2-methoxyestradiol (2ME), affect the rounding response of human vascular smooth muscle cells (SMCs) induced by ATV. Twenty-four hour treatment with ATV (10-100 microM) induced rounding of cultured human SMCs. Addition of 2ME (1-20 microM), but not 17beta-estradiol, for 2 h induced re-spreading of rounded cells. Our further studies showed that the effects of 2ME were mimicked by microtubule-disrupting drugs and inhibited by taxol. Inhibition of RhoA and ROCK (Rho-kinase) by C3-toxin and H-1152, respectively, blocked 2ME effects. 2ME effects were also blocked by treatment with either actin-interfering drugs, such as cytochalasin D and jasplakinolide, or myosin inhibitor blebbistatin. ML-7 and -9, the inhibitors for myosin light chain kinase, inhibited 2ME effect as well. ATV treatment induced a decrease of F-actin content and Thr18/Ser19 dual phosphorylation of myosin regulatory light chain (MRLC), which was rescued by 2ME or mevalonate. The rescue effects of 2ME on F-actin content and MRLC dual phosphorylation were abolished by taxol or H-1152. In addition, kinesin Eg5 inhibitor monastrol and dynein inhibitor erythro-9-3-(2-hydroxynonyl) adenine (EHNA) significantly blocked 2ME effects. Finally, our results revealed that 2ME inhibited the migration of SMCs induced by ATV (0.1 microM) in wound healing assay and Boyden chamber assay. In summary, our data show that 2ME, but not estrogen, inhibits ATV-induced rounding of human SMCs through induction of microtubule disassembly and activation of the Rho-ROCK-actinomyosin pathway.

Sex/gender medicine. The biological basis for personalized care in cardiovascular medicine

Sex differences in morbidity and mortality associated with cardiovascular disease have been recognized by the medical community for decades. Investigation into the underlying biological basis of these differences was largely neglected by the scientific community until a report released by the Institute of Medicine in the United States in 2001 "Exploring the Biological Contributions to Human Health: Does Sex Matter?" Recommendations from this report included the need for more accurate use of the terms "sex" and "gender", better tools and resources to study the biological basis of sex differences, integration of findings from different levels of biological organization and continued synergy between basic and clinical researchers. Ten years after the Institute's report, this review evaluates some of the sex differences in cardiovascular disease, reviews new approaches to study sex differences and emphasizes areas where further research is required. In the era of personalized medicine, the study of the biological basis of sex differences promises to optimize preventive, diagnostic and therapeutic strategies for cardiovascular disease in men and women, but will require diligence by the scientific and medical communities to remember that sex does matter.

Review: Prevention of coronary heart disease in women

Objective Coronary heart disease (CHD) mortality is higher in women than in men and misdiagnosis of CHD in women is one of the reasons for this, with differences in the presentation of CHD between men and women being a cause for the misdiagnosis. This review discusses the need for evidence-based guidelines to diagnose and treat CHD in women.

Methods Reviews, randomized controlled trials, and other studies pertinent to the topic were obtained using electronic search strategies, such as MEDLINE and Cochran Library, as well as manual selection. Sources selected were limited to those that discussed CHD, with specific emphasis placed on sources that focused on CHD in women. Selected studies were then assessed for quality of data and relevance via analysis of the study's methodology, results, and data. Results of selected studies were then stratified using a rating system devised to determine the quality of results using the scientific evidence provided for them. The references of the selected studies were then used to obtain and analyze additional studies in the same manner.

Results Control of lifestyle factors such as smoking, physical activity, diet, and weight are all necessary in women to control CHD, as is the maintenance of healthy lipid levels and blood pressure. Angiotensin-converting enzyme inhibitors and antiplatelets can help aid lifestyle changes in CHD management for women while hormone therapy and vitamin E have no proven benefits in CHD management.

Conclusions New gender- and evidence-based guidelines for the prevention of CHD in women need to be developed and adopted by physicians so that prevention, diagnosis, and treatment of CHD is made more effective.