Marine omega-3 fatty acid supplementation and prevention of cardiovascular disease: update on the randomized trial evidence

To date, the VITamin D and OmegA-3 TriaL (VITAL) is the only large-scale randomized trial of marine omega-3 fatty acid (n-3 FA) supplementation for cardiovascular disease (CVD) prevention in a general population unselected for elevated cardiovascular risk. We review the findings of VITAL, as well as results from recent secondary prevention trials and updated meta-analyses of n-3 FA trials in the primary and secondary prevention of CVD. In VITAL, a nationwide sample of 25 871 US adults aged 50 and older, including 5106 African Americans, were randomized in a 2 × 2 factorial design to n-3 FAs (1 g/day; 1.2:1 ratio of eicosapentaenoic to docosahexaenoic acid) and vitamin D3 (2000 IU/day) for a median of 5.3 years. Compared with an olive oil placebo, the n-3 FA intervention did not significantly reduce the primary endpoint of major CVD events [composite of myocardial infarction (MI), stroke, and CVD mortality; hazard ratio (HR) = 0.92 (95% confidence interval 0.80-1.06)] but did significantly reduce total MI [HR = 0.72 (0.59-0.90)], percutaneous coronary intervention [HR = 0.78 (0.63-0.95)], fatal MI [HR = 0.50 (0.26-0.97)], and recurrent (but not first) hospitalization for heart failure [HR = 0.86 (0.74-0.998)]. The intervention neither decreased nor increased risk of atrial fibrillation. African Americans derived the greatest treatment benefit for MI and for recurrent hospitalization for heart failure (P interaction < 0.05 for both outcomes). Meta-analyses that include VITAL and high-risk or secondary prevention n-3 FA trials show coronary, but generally not stroke, risk reduction. More research is needed to determine which individuals may be most likely to derive net benefit. (VITAL clinicaltrials.gov identifier: NCT01169259).

Design and baseline characteristics of participants in the COcoa Supplement and Multivitamin Outcomes Study (COSMOS)

Background Cocoa extract and multivitamins have been proposed to reduce the risk of cardiovascular disease (CVD) and cancer, respectively. However, few randomized clinical trials have tested their long-term effects on these outcomes. Methods The COcoa Supplement and Multivitamin Outcomes Study (COSMOS) is a randomized, double-blind, placebo-controlled, 2 × 2 factorial trial of a cocoa extract supplement and a multivitamin supplement to reduce the risk of CVD and cancer. Here we describe the pragmatic, hybrid design of the trial and baseline characteristics of the trial participants. Results The nationwide study population includes 21,442 U.S. women aged ≥65 years and men aged ≥60 years without baseline myocardial infarction (MI), stroke, or a recent (within the past 2 years) cancer diagnosis. Participants were randomized in a 2 × 2 factorial design to one of four groups: (1) cocoa extract (containing 500 mg/d flavanols, including 80 mg (-)-epicatechin) and a multivitamin (Centrum Silver©); (2) cocoa extract and multivitamin placebo; (3) multivitamin and cocoa extract placebo; or (4) both placebos. Randomization successfully distributed baseline demographic, clinical, behavioral, and dietary characteristics across treatment groups. Baseline biospecimens were collected from 6867 participants, with at least one follow-up biospecimen from 2142 participants. The primary outcome for the cocoa extract intervention is total CVD (a composite of MI, stroke, cardiovascular mortality, coronary revascularization, unstable angina requiring hospitalization, carotid artery surgery, and peripheral artery surgery); the primary outcome for the multivitamin intervention is total invasive cancer. Conclusion COSMOS will provide important information on the health effects of cocoa extract and multivitamin supplementation in older U.S. adults. Clinical Trials Registration: clinicaltrials.gov #NCT02422745.

The VITamin D and OmegA-3 TriaL (VITAL): Do Results Differ by Sex or Race/Ethnicity?

Whether vitamin D or marine omega-3 (n-3) fatty acid supplementation reduces risk of cancer or cardiovascular disease (CVD) in general populations at usual risk for these outcomes is relatively unexplored in randomized trials. The primary goal of the VITamin D and OmegA-3 TriaL (VITAL), a nationwide, randomized, placebo-controlled, 2 × 2 factorial trial of vitamin D₃ (2000 IU/day) and marine n-3 fatty acids (1 g/day) in the primary prevention of cancer and CVD among 25 871 US men aged ≥50 years and women aged ≥55 years, was to fill these knowledge gaps. Studying the influence of sex and race/ethnicity on treatment-related outcomes was a prespecified goal; such analyses help ensure that important effects are not missed and contribute to the foundation for developing targeted recommendations for supplement use. To enable investigation of potential sex- and race-specific treatment effects, trial investigators enrolled an even balance of men (n = 12 786) and women (n = 13 085) and oversampled African Americans (n = 5106). Significant or suggestive variation in intervention effects according to sex, race/ethnicity, and other participant characteristics was observed for some, though not all, outcomes. Additional research is needed to determine which individuals may be most likely to derive a net benefit from vitamin D or n-3 fatty acid supplementation. (VITAL clinicaltrials.gov identifier: NCT01169259).

Principal results of the VITamin D and OmegA-3 TriaL (VITAL) and updated meta-analyses of relevant vitamin D trials

Whether supplemental vitamin D reduces risk of cancer or cardiovascular disease (CVD) is relatively unexplored in randomized trial settings. The VITamin D and OmegA-3 TriaL (VITAL) was a nationwide, randomized, placebo-controlled, 2 × 2 factorial trial of daily vitamin D₃ (2000 IU) and marine omega-3 fatty acids (1 g) in the primary prevention of cancer and CVD among 25,871 U.S. men aged ≥50 and women aged ≥55, including 5106 African Americans. Median treatment duration was 5.3 years. Vitamin D did not significantly reduce the primary endpoint of total invasive cancer incidence (hazard ratio [HR] = 0.96 [95% confidence interval 0.88-1.06]) but showed a promising signal for reduction in total cancer mortality (HR = 0.83 [0.67-1.02]), especially in analyses that accounted for latency by excluding the first year (HR = 0.79 [0.63-0.99]) or first 2 years (HR = 0.75 [0.59-0.96]) of follow-up. Vitamin D did not significantly reduce the co-primary endpoint of major CVD events (HR = 0.97 [0.85-1.12]), other cardiovascular endpoints, or all-cause mortality (HR = 0.99 [0.87-1.12]). Updated meta-analyses that include VITAL and other recent vitamin D trials indicate a significant reduction in cancer mortality but not in cancer incidence or CVD endpoints. Additional research is needed to determine which individuals may be most likely to derive a net benefit from vitamin D supplementation. (VITAL clinicaltrials.gov identifier: NCT01169259).

Vitamin D, Marine n-3 Fatty Acids, and Primary Prevention of Cardiovascular Disease Current Evidence

Whether marine omega-3 fatty acid (n-3 FA) or vitamin D supplementation can prevent cardiovascular disease (CVD) in general populations at usual risk for this outcome is unknown. A major goal of VITAL (Vitamin D and Omega-3 Trial) was to fill this knowledge gap. In this article, we review the results of VITAL, discuss relevant mechanistic studies regarding n-3 FAs, vitamin D, and vascular disease, and summarize recent meta-analyses of the randomized trial evidence on these agents. VITAL was a nationwide, randomized, placebo-controlled, 2×2 factorial trial of marine n-3 FAs (1 g/d) and vitamin D₃ (2000 IU/d) in the primary prevention of CVD and cancer among 25 871 US men aged ≥50 and women aged ≥55 years, including 5106 blacks. Median treatment duration was 5.3 years. Supplemental n-3 FAs did not significantly reduce the primary cardiovascular end point of major CVD events (composite of myocardial infarction, stroke, and CVD mortality; hazard ratio [HR], 0.92 [95% CI, 0.80-1.06]) but were associated with significant reductions in total myocardial infarction (HR, 0.72 [95% CI, 0.59-0.90]), percutaneous coronary intervention (HR, 0.78 [95% CI, 0.63-0.95]), and fatal myocardial infarction (HR, 0.50 [95% CI, 0.26-0.97]) but not stroke or other cardiovascular end points. For major CVD events, a treatment benefit was seen in those with dietary fish intake below the cohort median of 1.5 servings/wk (HR, 0.81 [95% CI, 0.67-0.98]) but not in those above (P interaction=0.045). For myocardial infarction, the greatest risk reductions were in blacks (HR, 0.23 [95% CI, 0.11-0.47]; P interaction by race, 0.001). Vitamin D supplementation did not reduce major CVD events (HR, 0.97 [95% CI, 0.85-1.12]) or other cardiovascular end points. Updated meta-analyses that include VITAL and other recent trials document coronary risk reduction from supplemental marine n-3 FAs but no clear CVD risk reduction from supplemental vitamin D. Additional research is needed to determine which individuals may be most likely to derive net benefit from supplementation. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01169259.

Menopausal Estrogen-Alone Therapy and Health Outcomes in Women With and Without Bilateral Oophorectomy: A Randomized Trial

BACKGROUND

Whether health outcomes of menopausal estrogen therapy differ between women with and without bilateral salpingo-oophorectomy (BSO) is unknown.

OBJECTIVE

To examine estrogen therapy outcomes by BSO status, with additional stratification by 10-year age groups.

DESIGN

Subgroup analyses of the randomized Women's Health Initiative Estrogen-Alone Trial. (ClinicalTrials.gov: NCT00000611).

SETTING

40 U.S. clinical centers.

PARTICIPANTS

9939 women aged 50 to 79 years with prior hysterectomy and known oophorectomy status.

INTERVENTION

Conjugated equine estrogens (CEE) (0.625 mg/d) or placebo for a median of 7.2 years.

MEASUREMENTS

Incidence of coronary heart disease and invasive breast cancer (the trial's 2 primary end points), all-cause mortality, and a "global index" (these end points plus stroke, pulmonary embolism, colorectal cancer, and hip fracture) during the intervention phase and 18-year cumulative follow-up.

RESULTS

The effects of CEE alone did not differ significantly according to BSO status. However, age modified the effect of CEE in women with prior BSO. During the intervention phase, CEE was significantly associated with a net adverse effect (hazard ratio for global index, 1.42 [95% CI, 1.09 to 1.86]) in older women (aged ≥70 years), but the global index was not elevated in younger women (P trend by age = 0.016). During cumulative follow-up, women aged 50 to 59 years with BSO had a treatment-associated reduction in all-cause mortality (hazard ratio, 0.68 [CI, 0.48 to 0.96]), whereas older women with BSO had no reduction (P trend by age = 0.034). There was no significant association between CEE and outcomes among women with conserved ovaries, regardless of age.

LIMITATIONS

The timing of CEE in relation to BSO varied; several comparisons were made without adjustment for multiple testing.

CONCLUSION

The effects of CEE did not differ by BSO status in the overall cohort, but some findings varied by age. Among women with prior BSO, in those aged 70 years or older, CEE led to adverse effects during the treatment period, whereas women randomly assigned to CEE before age 60 seemed to derive mortality benefit over the long term.

PRIMARY FUNDING SOURCE

The WHI program is funded by the National Heart, Lung, and Blood Institute; National Institutes of Health; and U.S. Department of Health and Human Services. Wyeth Ayerst donated the study drugs.

Marine n-3 Fatty Acids and Prevention of Cardiovascular Disease and Cancer

BACKGROUND

Higher intake of marine n-3 (also called omega-3) fatty acids has been associated with reduced risks of cardiovascular disease and cancer in several observational studies. Whether supplementation with n-3 fatty acids has such effects in general populations at usual risk for these end points is unclear.

METHODS

We conducted a randomized, placebo-controlled trial, with a two-by-two factorial design, of vitamin D₃ (at a dose of 2000 IU per day) and marine n-3 fatty acids (at a dose of 1 g per day) in the primary prevention of cardiovascular disease and cancer among men 50 years of age or older and women 55 years of age or older in the United States. Primary end points were major cardiovascular events (a composite of myocardial infarction, stroke, or death from cardiovascular causes) and invasive cancer of any type. Secondary end points included individual components of the composite cardiovascular end point, the composite end point plus coronary revascularization (expanded composite of cardiovascular events), site-specific cancers, and death from cancer. Safety was also assessed. This article reports the results of the comparison of n-3 fatty acids with placebo.

RESULTS

A total of 25,871 participants, including 5106 black participants, underwent randomization. During a median follow-up of 5.3 years, a major cardiovascular event occurred in 386 participants in the n-3 group and in 419 in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI], 0.80 to 1.06; P=0.24). Invasive cancer was diagnosed in 820 participants in the n-3 group and in 797 in the placebo group (hazard ratio, 1.03; 95% CI, 0.93 to 1.13; P=0.56). In the analyses of key secondary end points, the hazard ratios were as follows: for the expanded composite end point of cardiovascular events, 0.93 (95% CI, 0.82 to 1.04); for total myocardial infarction, 0.72 (95% CI, 0.59 to 0.90); for total stroke, 1.04 (95% CI, 0.83 to 1.31); for death from cardiovascular causes, 0.96 (95% CI, 0.76 to 1.21); and for death from cancer (341 deaths from cancer), 0.97 (95% CI, 0.79 to 1.20). In the analysis of death from any cause (978 deaths overall), the hazard ratio was 1.02 (95% CI, 0.90 to 1.15). No excess risks of bleeding or other serious adverse events were observed.

CONCLUSIONS

Supplementation with n-3 fatty acids did not result in a lower incidence of major cardiovascular events or cancer than placebo. (Funded by the National Institutes of Health and others; VITAL ClinicalTrials.gov number, NCT01169259 .).

Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease

BACKGROUND

It is unclear whether supplementation with vitamin D reduces the risk of cancer or cardiovascular disease, and data from randomized trials are limited.

METHODS

We conducted a nationwide, randomized, placebo-controlled trial, with a two-by-two factorial design, of vitamin D₃ (cholecalciferol) at a dose of 2000 IU per day and marine n-3 (also called omega-3) fatty acids at a dose of 1 g per day for the prevention of cancer and cardiovascular disease among men 50 years of age or older and women 55 years of age or older in the United States. Primary end points were invasive cancer of any type and major cardiovascular events (a composite of myocardial infarction, stroke, or death from cardiovascular causes). Secondary end points included site-specific cancers, death from cancer, and additional cardiovascular events. This article reports the results of the comparison of vitamin D with placebo.

RESULTS

A total of 25,871 participants, including 5106 black participants, underwent randomization. Supplementation with vitamin D was not associated with a lower risk of either of the primary end points. During a median follow-up of 5.3 years, cancer was diagnosed in 1617 participants (793 in the vitamin D group and 824 in the placebo group; hazard ratio, 0.96; 95% confidence interval [CI], 0.88 to 1.06; P=0.47). A major cardiovascular event occurred in 805 participants (396 in the vitamin D group and 409 in the placebo group; hazard ratio, 0.97; 95% CI, 0.85 to 1.12; P=0.69). In the analyses of secondary end points, the hazard ratios were as follows: for death from cancer (341 deaths), 0.83 (95% CI, 0.67 to 1.02); for breast cancer, 1.02 (95% CI, 0.79 to 1.31); for prostate cancer, 0.88 (95% CI, 0.72 to 1.07); for colorectal cancer, 1.09 (95% CI, 0.73 to 1.62); for the expanded composite end point of major cardiovascular events plus coronary revascularization, 0.96 (95% CI, 0.86 to 1.08); for myocardial infarction, 0.96 (95% CI, 0.78 to 1.19); for stroke, 0.95 (95% CI, 0.76 to 1.20); and for death from cardiovascular causes, 1.11 (95% CI, 0.88 to 1.40). In the analysis of death from any cause (978 deaths), the hazard ratio was 0.99 (95% CI, 0.87 to 1.12). No excess risks of hypercalcemia or other adverse events were identified.

CONCLUSIONS

Supplementation with vitamin D did not result in a lower incidence of invasive cancer or cardiovascular events than placebo. (Funded by the National Institutes of Health and others; VITAL ClinicalTrials.gov number, NCT01169259 .).

Invited Commentary: The Framingham Offspring Study-A Pioneering Investigation Into Familial Aggregation of Cardiovascular Risk

Launched in 1948, the Framingham Heart Study was a seminal prospective cohort study of 5,209 adult residents of Framingham, Massachusetts, that was designed to uncover the determinants and natural history of coronary heart disease. Data from this original cohort established the cardiac threat posed by high blood pressure, high cholesterol, smoking, obesity, physical inactivity, diabetes, and other factors. In the late 1960s, investigators conceived the innovative idea of assembling a second cohort that comprised the adult children of the original study population (and these children's spouses). From 1971 to 1975, a total of 5,124 individuals were recruited to form the Offspring Cohort. Studying successive generations in this fashion provided an efficient method for examining secular trends in cardiovascular disease and its risk factors, as well as an opportunity to assess familial aggregation of risk without the threat of recall bias. In a paper published in the September 1979 issue of the Journal, then study director William Kannel et al. (Am J Epidemiol. 1979;110(3):281-290) described the sampling design of the Offspring Study and presented selected baseline characteristics of the cohort. The scientific questions addressed by this research provided the impetus for a decades-long effort-still in full force today both within the Framingham Study itself and in the broader cardiovascular epidemiologic community-to quantify the independent and synergistic effects of genetic, lifestyle, and other environmental factors on cardiovascular outcomes.

The Relationship Between Intimate Partner Violence and the Use of Addictive Substances in Poor and Homeless Single Mothers

This study examines the contributions of adult partner violence, childhood physical abuse and sexual molestation, post-traumatic stress disorder (PTSD), and partners'sub-stance use on poor women's use of addictive substances. Utilizing a longitudinal data set, researchers found that women with histories of partner violence had nearly three times the odds of using illegal drugs at follow-up. Reverse causation (i.e., substance use increases the likelihood of violent relationships) did not explain the association. Confounding by childhood sexual molestation and mediation by PTSD also did not fully account for the violence–drug use link. Partners' substance use was independently related to women's follow-up drug and alcohol use. Program and policy implications are reviewed

The timing hypothesis: Do coronary risks of menopausal hormone therapy vary by age or time since menopause onset?

The Women's Health Initiative (WHI), a landmark randomized trial of menopausal hormone therapy (HT) for prevention of chronic disease in postmenopausal women aged 50-79, established that such therapy neither prevents coronary heart disease (CHD) nor yields a favorable balance of benefits and risks in such women as a whole. However, a nuanced look at the data from this trial, considered alongside other evidence, suggests that timing of HT initiation affects the relation between such therapy and coronary risk, as well as its overall benefit-risk balance. Estrogen may have a beneficial effect on the heart if started in early menopause, when a woman's arteries are likely to be relatively healthy, but a harmful effect if started in late menopause, when those arteries are more likely to show signs of atherosclerotic disease. However, even if HT-associated relative risks are constant across age or time since menopause onset, the low absolute risk of CHD in younger or recently menopausal women translates into low attributable risks in this group. Thus, HT initiation for relief of moderate to severe vasomotor symptoms in early menopausal patients who have a favorable coronary profile remains a viable option.

Baseline characteristics of participants in the VITamin D and OmegA-3 TriaL (VITAL)

Evidence for a role of supplemental vitamin D and marine omega-3 fatty acids in preventing cancer and cardiovascular disease (CVD) remains inconclusive and insufficient to inform nutritional recommendations for primary prevention. The VITamin D and Omega-A 3 TriaL (VITAL) is an ongoing nationwide, randomized, double-blind, placebo-controlled clinical trial designed to fill this knowledge gap. The study population consists of 25,874 U.S. adults without cancer or CVD at baseline, who were selected only on age (men aged ≥50 and women aged ≥55), with an oversampling of African Americans (n=5,107). In a 2 × 2 factorial design, participants were randomized to one of four supplement groups: [1] active vitamin D3 (cholecalciferol; 2000 IU/d) and active marine omega-3 fatty acids (Omacor® fish oil, eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA], 1g/d); [2] active vitamin D and omega-3 placebo; [3] vitamin D placebo and active marine omega-3 fatty acids; or [4] vitamin D placebo and omega-3 placebo. The mean length of the randomized treatment period will be 5 years. The randomization was successful, as evidenced by similar distributions of baseline demographic, health, and behavioral characteristics across treatment groups. The similar distribution of known potential confounders across treatment groups strongly suggests that unmeasured or unknown potential confounders are also equally distributed. VITAL is expected to provide important information on the benefit-risk balance of vitamin D and omega-3 fatty acid supplementation when taken for the primary prevention of cancer and CVD.

Prospective Analysis of Health and Mortality Risk in Veteran and Non-Veteran Participants in the Women's Health Initiative

BACKGROUND

The health of postmenopausal women veterans is a neglected area of study. A stronger empirical evidence base is needed, and would inform the provision of health care for the nearly 1 million U.S. women veterans currently 50 years of age or older. To this end, the present work compares salient health outcomes and risk of all-cause mortality among veteran and non-veteran participants of the Women's Health Initiative (WHI).

METHODS

This study features prospective analysis of long-term health outcomes and mortality risk (average follow-up, 8 years) among the 3,706 women veterans and 141,009 non-veterans who participated in the WHI Observational Study or Clinical Trials. Outcome measurements included confirmed incident cases of cardiovascular disease (CVD), cancer, diabetes, hip fractures, and all-cause mortality.

RESULTS

We identified 17,968 cases of CVD, 19,152 cases of cancer, 18,718 cases of diabetes, 2,817 cases of hip fracture, and 13,747 deaths. In Cox regression models adjusted for age, sociodemographic variables, and health risk factors, veteran status was associated with significantly increased risk of all-cause mortality (hazard ratio [HR], 1.13; 95% CI, 1.03-1.23), but not with risk of CVD (HR, 1.00; 95% CI, 0.90-1.11), cancer (HR, 1.04; 95% CI, 0.95-1.14), hip fracture (HR, 1.16; 95% CI, 0.94-1.43), or diabetes (HR, 1.00; 95% CI, 0.89-1.1).

CONCLUSIONS

Women veterans' postmenopausal health, particularly risk for all-cause mortality, warrants further consideration. In particular, efforts to identify and address modifiable risk factors associated with all-cause mortality are needed.

Biomarkers of cardiovascular disease risk in women

Cardiovascular disease (CVD), including coronary heart disease and stroke, is the leading cause of death among U.S. women and men. Established cardiovascular risk factors such as smoking, diabetes, hypertension, and elevated total cholesterol, and risk prediction models based on such factors, perform well but do not perfectly predict future risk of CVD. Thus, there has been much recent interest among cardiovascular researchers in identifying novel biomarkers to aid in risk prediction. Such markers include alternative lipids, B-type natriuretic peptides, high-sensitivity troponin, coronary artery calcium, and genetic markers. This article reviews the role of traditional cardiovascular risk factors, risk prediction tools, and selected novel biomarkers and other exposures in predicting risk of developing CVD in women. The predictive role of novel cardiovascular biomarkers for women in primary prevention settings requires additional study, as does the diagnostic and prognostic utility of cardiac troponins for acute coronary syndromes in clinical settings. Sex differences in the clinical expression and physiology of metabolic syndrome may have implications for cardiovascular outcomes. Consideration of exposures that are unique to, or more prevalent in, women may also help to refine cardiovascular risk estimates in this group.

Oral contraceptives and menopausal hormone therapy: relative and attributable risks of cardiovascular disease, cancer, and other health outcomes

PURPOSE

To summarize the relative risks (RRs) and attributable risks (ARs) of major health outcomes associated with use of combined oral contraceptives (OCs) and menopausal hormone therapy (HT).

METHODS

For OCs, measures of association are from meta-analyses of observational studies. For HT, these measures are from the Women's Health Initiative, a large randomized trial of HT for chronic disease prevention in postmenopausal women aged 50 to 79 years.

RESULTS

Current OC use increases risks of venous thromboembolism and ischemic stroke. However, women of reproductive age are at low baseline risk, so the ARs are small. OC use also increases risk of breast and liver cancer and reduces risk of ovarian, endometrial, and colorectal cancer; the net effect is a modest reduction in total cancer. The Women's Health Initiative results show that HT does not prevent coronary events or overall chronic disease in postmenopausal women as a whole. Subgroup analyses suggest that timing of HT initiation influences the relation between such therapy and coronary risk, and its overall risk-benefit balance, with more favorable effects (on a relative scale) in younger or recently menopausal women than in older women or those further past the menopausal transition. However, even if the RR do not vary by these characteristics, the low absolute baseline risks of younger or recently menopausal women translate into low ARs in this group.

CONCLUSIONS

OC and HT can safely be used for contraception and treatment of vasomotor symptoms, respectively, by healthy women at low baseline risk for cardiovascular disease and breast cancer.

Oral contraceptives and menopausal hormone therapy: relative and attributable risks of cardiovascular disease, cancer, and other health outcomes

PURPOSE

To summarize the relative risks (RRs) and attributable risks (ARs) of major health outcomes associated with use of combined oral contraceptives (OCs) and menopausal hormone therapy (HT).

METHODS

For OCs, measures of association are from meta-analyses of observational studies. For HT, these measures are from the Women's Health Initiative, a large randomized trial of HT for chronic disease prevention in postmenopausal women aged 50 to 79 years.

RESULTS

Current OC use increases risks of venous thromboembolism and ischemic stroke. However, women of reproductive age are at low baseline risk, so the ARs are small. OC use also increases risk of breast and liver cancer and reduces risk of ovarian, endometrial, and colorectal cancer; the net effect is a modest reduction in total cancer. The Women's Health Initiative results show that HT does not prevent coronary events or overall chronic disease in postmenopausal women as a whole. Subgroup analyses suggest that timing of HT initiation influences the relation between such therapy and coronary risk, and its overall risk-benefit balance, with more favorable effects (on a relative scale) in younger or recently menopausal women than in older women or those further past the menopausal transition. However, even if the RR do not vary by these characteristics, the low absolute baseline risks of younger or recently menopausal women translate into low ARs in this group.

CONCLUSIONS

OC and HT can safely be used for contraception and treatment of vasomotor symptoms, respectively, by healthy women at low baseline risk for cardiovascular disease and breast cancer.

Menopausal hormone therapy and cardiovascular disease risk: utility of biomarkers and clinical factors for risk stratification

BACKGROUND

Menopausal hormone therapy (HT) continues to have a clinical role in symptom management, but identifying women for whom benefits will outweigh the risks remains a challenge. Although hormone therapy (HT) is the most effective strategy for ameliorating vasomotor and other symptoms, randomized clinical trials show an unfavorable balance of benefits and risks for many women. However, closer examination of data from these trials suggests that it may be possible to classify women as better or worse candidates for HT by using individual risk stratification.

CONTENT

Data from 2 landmark trials-the Women's Health Initiative (WHI) and the Heart and Estrogen/progestin Replacement Study (HERS)-suggest an important role for clinical characteristics, serum biomarkers, genomic markers, and gene-environment interactions in developing a personalized approach to the prediction of risk for cardiovascular disease (CVD) events for women while on HT. The available data suggest several characteristics of women who are optimal candidates for HT use: younger age (<60 years), recent onset of menopause (<10 years), favorable lipid profile (LDL cholesterol <130 mg/dL or LDL/HDL cholesterol ratio <2.5), absence of metabolic syndrome, and absence of factor V Leiden genotype. The identification of other characteristics is an area of active investigation. In addition, women at high risk for venous thromboembolism should avoid systemic HT or choose a transdermal rather than oral delivery route.

SUMMARY

Personalized medicine-i.e., the use of the specific biological profile of an individual to guide the choice of treatment-is highly relevant for clinical decision-making regarding HT and offers promise for improved treatment efficacy and safety.

Physical Activity and Health in Women

Medical authorities advise US adults to perform a minimum of 30 minutes of moderate-intensity aerobic physical activity on most days of the week to improve health and reduce risk for many chronic conditions. New findings from epidemiologic studies suggest that physical activity not only reduces the risk of developing coronary heart disease, stroke, and type 2 diabetes but also may prevent certain cancers (including colon and breast cancer), osteoporotic fracture, falls, cognitive decline, mood disturbances, and adverse pregnancy outcomes. Physical activity is important for regulating body weight, but many cardiometabolic benefits of exercise are independent of such regulation. This article reviews recent epidemiologic evidence on physical activity with respect to a variety of health outcomes in women and concludes with guidance for clinicians seeking to boost activity levels in sedentary patients. However, additional research is needed on features of individual- and community-based interventions and policies that successfully promote healthful levels of physical activity.

The VITamin D and OmegA-3 TriaL (VITAL): rationale and design of a large randomized controlled trial of vitamin D and marine omega-3 fatty acid supplements for the primary prevention of cancer and cardiovascular disease

Data from laboratory studies, observational research, and/or secondary prevention trials suggest that vitamin D and marine omega-3 fatty acids may reduce risk for cancer or cardiovascular disease (CVD), but primary prevention trials with adequate dosing in general populations (i.e., unselected for disease risk) are lacking. The ongoing VITamin D and OmegA-3 TriaL (VITAL) is a large randomized, double-blind, placebo-controlled, 2 x 2 factorial trial of vitamin D (in the form of vitamin D(3) [cholecalciferol], 2000 IU/day) and marine omega-3 fatty acid (Omacor fish oil, eicosapentaenoic acid [EPA]+docosahexaenoic acid [DHA], 1g/day) supplements in the primary prevention of cancer and CVD among a multi-ethnic population of 20,000 U.S. men aged ≥ 50 and women aged ≥ 55. The mean treatment period will be 5 years. Baseline blood samples will be collected in at least 16,000 participants, with follow-up blood collection in about 6000 participants. Yearly follow-up questionnaires will assess treatment compliance (plasma biomarker measures will also assess compliance in a random sample of participants), use of non-study drugs or supplements, occurrence of endpoints, and cancer and vascular risk factors. Self-reported endpoints will be confirmed by medical record review by physicians blinded to treatment assignment, and deaths will be ascertained through national registries and other sources. Ancillary studies will investigate whether these agents affect risk for diabetes and glucose intolerance; hypertension; cognitive decline; depression; osteoporosis and fracture; physical disability and falls; asthma and other respiratory diseases; infections; and rheumatoid arthritis, systemic lupus erythematosus, thyroid diseases, and other autoimmune disorders.

Physical activity and cardiovascular disease prevention in women: a review of the epidemiologic evidence

Epidemiologic studies suggest that as little as 30minutes of moderate-intensity physical activity per day can lower the risk of developing cardiovascular disease in women. Sedentary individuals who become physically active even at older ages derive cardiovascular benefits. Physical activity appears to slow the initiation and progression of CVD through salutary effects not only on adiposity but also on insulin sensitivity, glycemic control, incident type 2 diabetes, blood pressure, lipids, endothelial function, hemostasis, and inflammatory defense systems. Public health initiatives that promote moderate increases in physical activity may offer the best balance between efficacy and feasibility to improve cardiovascular health in sedentary populations.

Does vitamin D protect against cardiovascular disease?

Because of its role in maintaining bone density, vitamin D has long been recognized as critical to the health of women, a group at disproportionate risk of osteoporosis. Recent data from epidemiologic and laboratory studies suggest that vitamin D may also protect against the development of cardiovascular and other chronic diseases. Because three quarters of US women (and men) have suboptimal vitamin D status, many experts advocate increasing daily recommended intakes from 200-600 IU to at least 1,000 IU, which may indeed be a prudent strategy. However, data from large randomized clinical trials testing sufficiently high doses of this vitamin for cardiovascular disease prevention--as well as to assess the overall balance of benefits and risks of such supplementation--are needed.

Reassessing Benefits and Risks of Hormone Therapy

Recent randomized clinical trials of postmenopausal hormone therapy have informed clinical decision making and provided insights that help identify appropriate candidates for treatment. A decline in the use of hormone therapy began precipitously in 2002 with publication of data from the Women's Health Initiative. This review examines the scientific literature surrounding this major change in practice and comments on the equilibrating process now taking place. Notably, the incidence of most of the medical conditions adversely affected by hormone therapy increases with age. As a result, recently menopausal women—those most interested in using hormone therapy—are at lower absolute risk of adverse events than older women. A critical mass of data now suggests that age and time since menopause may also modify relative risks of selected outcomes with use of hormone therapy, but this warrants further study. Duration of hormone therapy use also appears to influence risk, with the occurrence of certain outcomes (such as venous thrombosis) being highest in the first 1 or 2 years of hormone therapy use and others (such as breast cancer) increasing with longer duration of hormone therapy use. The conflicting results for some outcomes from the estrogen arm and the estrogen-progestin arm of the Women's Health Initiative suggest that progestins influence risk of several diseases, particularly breast cancer. Quantifying the benefits and risks of estrogen and estrogen-progestin by age group makes it possible to discuss pros and cons of hormone therapy in a more clinically relevant manner with patients. Hormone therapy remains a viable short-term option for the management of moderate to severe vasomotor symptoms in recently menopausal women who are in generally good health. However, due to known risks, it should not be initiated or continued for the express purpose of preventing cardiovascular disease or other chronic diseases.

Invited commentary: hormone therapy and risk of coronary heart disease why renew the focus on the early years of menopause?

After the initial report from the Women's Health Initiative estrogen-progestin trial, which found that menopausal hormone therapy was associated with an increased risk of coronary heart disease in the overall cohort (age range: 50-79 years; mean age: 63 years), researchers took a closer look at the data from this and other studies, focusing on the timing of initiation of such therapy. The results suggest that hormone therapy may have a beneficial effect on the heart if started in early menopause, when a woman's arteries are still likely to be relatively healthy, but a harmful effect if started in late menopause, when advanced atherosclerosis may be present. The implication of the timing hypothesis for clinical practice is not that recently menopausal women be given hormone therapy for coronary heart disease prevention but rather that clinicians can be reassured about cardiac risks when considering short-term use of hormone therapy for vasomotor symptom relief in such women. The reduction in vasomotor symptoms must be weighed against other risks and benefits of treatment, but coronary disease is typically not a major factor in the equation for women who are recently menopausal.

Social engagement and depressive symptoms in late life: longitudinal findings

OBJECTIVE

The purpose is to investigate whether social engagement protects against depressive symptoms in older adults.

METHOD

Three waves of data from a representative cohort study of community-dwelling adults aged 65 years and above from the New Haven Established Populations for the Epidemiologic Study of the Elderly are examined using random effects models.

RESULTS

Social engagement (an index combining social and productive activity) is associated with lower CES-D scores after adjustment for age, sex, time, education, marital status, health and functional status, and fitness activities. This association is generally constant with time, suggesting a cross-sectional association. In addition, social engagement is associated with change in depressive symptoms, but only among those with CES-D scores below 16 at baseline.

DISCUSSION

Social engagement is independently associated with depressive symptoms cross-sectionally. A longitudinal association is seen only among those not depressed at baseline.

Postmenopausal hormone therapy: new questions and the case for new clinical trials

Observational studies suggest that postmenopausal hormone therapy (HT) prevents coronary heart disease, whereas randomized clinical trials have not confirmed a cardioprotective effect. Although observational studies may have overestimated the coronary benefit conferred by postmenopausal hormone use, there are other plausible explanations for the apparent discrepancy between previous results and the less favorable findings from clinical trials such as the large Women's Health Initiative. There is now a critical mass of data to support the hypothesis that age or time since menopause may importantly influence the benefit-risk ratio associated with HT, especially with respect to cardiovascular outcomes, and that the method of administration, dose, and formulation of exogenous hormones may also be relevant. Although the weight of the evidence indicates that older women and those with subclinical or overt coronary heart disease should not take HT, estrogen remains the most effective treatment currently available for vasomotor symptoms, and its effects on the development of coronary disease in newly postmenopausal women remain unclear. Moreover, effects of HT on quality of life and cognitive function in recently postmenopausal women merit further study. These unresolved clinical issues provide the rationale for the design of the Kronos Early Estrogen Prevention Study, a 5-year randomized trial that will evaluate the effectiveness of low-dose oral estrogen and transdermal estradiol in preventing progression of atherosclerosis in recently postmenopausal women.

Epidemiological evidence for the role of physical activity in reducing risk of type 2 diabetes and cardiovascular disease

Epidemiological studies suggest that physically active individuals have a 30-50% lower risk of developing type 2 diabetes than do sedentary persons and that physical activity confers a similar risk reduction for coronary heart disease. Risk reductions are observed with as little as 30 min of moderate-intensity activity per day. Protective mechanisms of physical activity include the regulation of body weight; the reduction of insulin resistance, hypertension, atherogenic dyslipidemia, and inflammation; and the enhancement of insulin sensitivity, glycemic control, and fibrinolytic and endothelial function. Public health initiatives promoting moderate increases in physical activity may offer the best balance between efficacy and feasibility to improve metabolic and cardiovascular health in largely sedentary populations.

High-sensitivity C-reactive protein: clinical importance

High-sensitivity C-reactive protein (hsCRP) is a marker of inflammation that predicts incident myocardial infarction, stroke, peripheral arterial disease, and sudden cardiac death among healthy individuals with no history of cardiovascular disease, and recurrent events and death in patients with acute or stable coronary syndromes. hsCRP confers additional prognostic value at all levels of cholesterol, Framingham coronary risk score, severity of the metabolic syndrome, and blood pressure, and in those with and without subclinical atherosclerosis. hsCRP levels of less than 1, 1 to 3, and greater than 3 mg/L are associated with lower, moderate, and higher cardiovascular risks, respectively. This article summarizes epidemiologic data on the relation between CRP and atherothrombotic disease and provides clinical guidelines for hsCRP screening in cardiovascular risk assessment.

The Women's Antioxidant Cardiovascular Study: Design and Baseline Characteristics of Participants

BACKGROUND

The evidence for a potential benefit of antioxidant vitamins and folic acid in cardiovascular disease (CVD) prevention is derived from laboratory, clinical, and observational epidemiological studies but remains inconclusive. Large-scale randomized trials with clinical end points are necessary to minimize confounding and provide unbiased estimates of the balance of benefits and risks, yet data from such trials are scarce, especially among women.

METHODS

The Women's Antioxidant Cardiovascular Study (WACS) is a randomized, double-blind, placebo-controlled trial testing whether antioxidant vitamins and a folic acid/vitamin B(6)/vitamin B(12) combination prevent future cardiovascular events among women with preexisting CVD or >or=3 CVD risk factors. This paper describes the design of the trial and baseline characteristics of participants, evaluates the success of randomization, and addresses the generalizability of future findings.

RESULTS

In a factorial design, 8171 U.S. female health professionals aged >or=40 years were randomized to vitamin E, vitamin C, beta-carotene, or placebos. Of these women, 5442 were also subsequently randomized to folic acid/vitamin B(6)/vitamin B(12) or placebo. The randomization was successful, as evidenced by similar distributions of baseline demographic, health, and behavioral characteristics across treatment groups. The clinical profile of participants was similar to that observed in another large trial of women with CVD.

CONCLUSIONS

The similar distribution of known potential confounders across treatment groups provides reassurance that unmeasured or unknown potential confounders are also equally distributed. Although a definitive conclusion regarding generalizability requires additional trials in diverse populations, there is little biological basis for supposing that the benefit-risk balance differs in other high-risk women.

Physical Activity and Cardiovascular Disease Prevention in Women: How Much Is Good Enough?

Epidemiologic data suggest that 30 min x d(-1) of brisk walking can reduce cardiovascular disease incidence in women and men. In a sedentary society, public health initiatives that promote moderate increases in physical activity may represent the optimal balance between efficacy, feasibility, and safety to achieve the desired cardioprotective effect.

Characteristics of the Modified Mini-Mental State Exam among elderly persons

This study assesses psychometric properties of the Modified Mini-Mental State Exam (3MS) and present population norms and demographic risk factors for low 3MS scores. The subjects were 885 persons aged 65 and older who took the 3MS as part of the Stirling County Study, a population-based longitudinal study of adult residents of a county in Atlantic Canada. 3MS scores were not dependent on the specific rater who scored the test; thus, the 3MS is free of rater bias. Interrater reliability was high (intraclass correlation coefficient=0.98), as was internal consistency (coefficient alpha=0.91). Test-retest reliability over 3 years was 0.78. One third of subjects tested as cognitively impaired. Risk factors for low scores include older age, less education, male gender, and examination in French. The correlation between 3MS and Mini Mental State Exam scores was 0.95. The 3MS can be used as an epidemiologic measure of global cognitive performance among elderly persons.

Physical activity and the prevention of cardiovascular disease

This article summarizes recent evidence on the role of physical activity in the prevention of overt and subclinical vascular disease. Epidemiologic data suggest that as little as 30 minutes per day of moderate-intensity physical activity, including brisk walking, reduces the incidence of clinical cardiovascular events in men and women. Regular exercise may also retard the progression of asymptomatic coronary and peripheral arteriosclerosis. Cardioprotective mechanisms of physical activity include reducing adiposity, blood pressure, diabetes incidence, dyslipidemia, and inflammation, and enhancing insulin sensitivity, glycemic control, fibrinolysis, and endothelial function. In a sedentary society such as the United States, public health initiatives that promote moderate increases in activity represent the optimal balance between efficacy and feasibility to achieve desired improvements in cardiovascular health.

Does vitamin E supplementation prevent cardiovascular events?

In recent years, vitamin E has been investigated as a cardioprotective agent. Experimental studies have identified potential mechanisms by which vitamin E may inhibit the development of atherosclerosis, and observational studies of individuals without coronary disease suggest that vitamin E intake may prevent future cardiovascular events. Secondary prevention trials to date have demonstrated little benefit from vitamin E supplementation. It remains possible, however, that supplementation may be useful among certain high-risk groups, including those with nutritional deficiencies. Limited data from completed primary prevention trials also indicate minimal cardioprotection from vitamin E, but large-scale trials now in progress may yet show benefit. Results from ongoing trials will contribute powerfully to the totality of evidence on which to formulate both appropriate clinical recommendations for individual patients and a rational public health policy for the population as a whole. At this time, there is insufficient evidence for issuing a public health recommendation to use vitamin E supplements to prevent cardiovascular disease (CVD). Rather, increased intake of fruits, vegetables, and other antioxidant-rich foods should be promoted as part of a healthy diet because they provide nutritional benefits beyond any potential antioxidant effect. Moreover, even if found to reduce CVD risk, vitamin supplement use should be considered an adjunct, not an alternative, to established cardioprotective measures, such as smoking abstention, avoidance of obesity, adequate physical activity, and control of high blood pressure and hyperlipidemia.

Socioeconomic status and mortality among the elderly: findings from four US communities

The effect of socioeconomic status (SES) on mortality was examined in the community-dwelling elderly. Data were obtained from four population-based studies that enrolled elderly residents of four US communities (East Boston, Massachusetts; New Haven, Connecticut; east-central Iowa; and the Piedmont region of North Carolina) and followed them for 9 years, starting in 1982 or 1986. Higher SES, whether measured by education, by household income, or by occupational prestige, was generally associated with lower mortality. However, the pattern of findings varied by gender and by community. For men, all three SES indicators were associated with mortality in the majority of cohorts. For women, this was true only for income. SES-mortality associations were attenuated but not eliminated after adjustment for behavior and health status. SES-mortality associations were stronger in New Haven and North Carolina than in East Boston and Iowa. The latter communities are more homogeneous with respect to ethnicity, urbanization, and occupational history than the former. Future research should investigate the relative validity of traditional SES measures for men and women and develop more balanced assessment methods. These findings also suggest that it is important to consider not only individual characteristics but also community attributes that mediate or modify the pathways through which socioeconomic conditions may influence health.

Cognitive impairment and mortality in the community-dwelling elderly

The effects on mortality of cognitive impairment and 3-year declines in cognitive function were examined among community-dwelling adults aged 68 years or more. Data were taken from a population-based cohort study that enrolled noninstitutionalized elderly residents of New Haven, Connecticut, and followed them by conducting in-home interviews in 1982, 1985, 1988, and 1994. The cognitive function of 1,997 respondents was assessed by using the 30-point Mini-Mental State Examination in 1985; 1,372 respondents (86% of those alive) were retested in 1988. Responses were classified as high normal (28-30), low normal (24-27), mild impairment (18-23), or severe impairment (0-17); cognitive decline was defined as a transition to a lower category. After control for multiple potential confounders, both severe and mild cognitive impairment were strongly predictive of subsequent mortality among respondents aged less than 80 years. Upon closer examination, the elevated mortality risk was observed primarily among respondents whose cognitive decline was recent rather than among those whose cognitive performance was compromised but stable. Among respondents aged 80 years or more, declines to severe cognitive impairment were predictive of mortality, but it was not clear whether the decline per se signaled an unfavorable prognosis not accounted for by the resulting impairment level. Cognitive declines, especially those in the young elderly, have a marked adverse impact on survival.

Social disengagement and incident cognitive decline in community-dwelling elderly persons

BACKGROUND

Social engagement, which is defined as the maintenance of many social connections and a high level of participation in social activities, has been thought to prevent cognitive decline in elderly persons. However, few longitudinal studies of this relation have been done.

OBJECTIVE

To determine the relation between social disengagement and incident cognitive decline in community-dwelling elderly persons.

DESIGN

Cohort study.

SETTING

New Haven, Connecticut.

PARTICIPANTS

2812 noninstitutionalized elderly persons (65 years of age or older) who were interviewed in their homes in 1982, 1985, 1988, and 1994.

MEASUREMENTS

A global social disengagement scale was constructed from the following indicators: presence of a spouse, monthly visual contact with three or more relatives or friends, yearly nonvisual contact with 10 or more relatives or friends, attendance at religious services, group membership, and regular social activities. Cognitive function was assessed with the Short Portable Mental Status Questionnaire. Response to the questionnaire was scored as high, medium, or low. Cognitive decline was defined as a transition to a lower category.

RESULTS

Compared with persons who had five or six social ties, those who had no social ties were at increased risk for incident cognitive decline after adjustment for age, initial cognitive performance, sex, ethnicity, education, income, housing type, physical disability, cardiovascular profile, sensory impairment, symptoms of depression, smoking, alcohol use, and level of physical activity. The 3-year odds ratio was 2.24 (95% CI, 1.40 to 3.58; P < 0.001), the 6-year odds ratio was 1.91 (CI, 1.14 to 3.18; P = 0.01), and the 12-year odds ratio was 2.37 (CI, 1.07 to 4.88; P = 0.03).

CONCLUSION

Social disengagement is a risk factor for cognitive impairment among elderly persons.

Depressive symptomatology and incident cognitive decline in an elderly community sample

BACKGROUND

It is not known whether depression is a cause or consequence of progressive cognitive decline. We assessed the relationship between depressive symptoms and subsequent cognitive decline in the community-dwelling elderly population.

METHODS

Data were from a population-based cohort study that enrolled 2812 noninstitutionalized elderly residents of New Haven, Conn, and followed them with in-home visits in 1982, 1985, 1988, and 1994. Cognitive function was assessed with the Short Portable Mental Status Questionnaire (SPMSQ). Response to the SPMSQ was scored as high, medium, and low, and cognitive decline was defined as a transition to a lower category. Depressive symptoms were measured with the Center for Epidemiological Studies Depression Scale.

RESULTS

An elevated level of depressive symptoms was associated with an increased risk of incident cognitive decline among medium SPMSQ performers (3-year odds ratio [OR], 1.72; 95% confidence interval [CI], 1.04-2.82, P=.03; 6-year OR, 2.40; 95% CI, 1.33-4.34; P=.004; 12-year OR, 1.65; 95% CI, 0.62-4.38; P=.31) but not among high performers (3-year OR, 0.93; 95% CI, 0.62-1.39; P=.71; 6-year OR, 1.03; 95% CI, 0.67-1.58; P=.90; 12-year OR, 1.26; 95% CI, 0.59-2.71; P=.55), after adjustment for age, sex, race, education, income, housing type, functional disability, cardiovascular profile, and alcohol use.

CONCLUSIONS

Depressive symptoms, particularly dysphoric mood, presage future cognitive losses among elderly persons with moderate cognitive impairments. However, the data do not provide support for the hypothesis that depressive symptoms are associated with the onset or rate of cognitive decline among cognitively intact elderly persons.