Effect of homocysteine lowering on mortality and vascular disease in advanced chronic kidney disease and end-stage renal disease: a randomized controlled trial

Context  High plasma homocysteine levels are a risk factor for mortality and vascular disease in observational studies of patients with chronic kidney disease. Folic acid and B vitamins decrease homocysteine levels in this population but whether they lower mortality is unknown. Objective  To determine whether high doses of folic acid and B vitamins administered daily reduce mortality in patients with chronic kidney disease. Design, Setting, and Participants  Double-blind randomized controlled trial (2001-2006) in 36 US Department of Veterans Affairs medical centers. Median follow-up was 3.2 years for 2056 participants aged 21 years or older with advanced chronic kidney disease (estimated creatinine clearance 30 mL/min) (n = 1305) or end-stage renal disease (n = 751) and high homocysteine levels ( 15 µmol/L). Intervention  Participants received a daily capsule containing 40 mg of folic acid, 100 mg of pyridoxine hydrochloride (vitamin B₆), and 2 mg of cyanocobalamin (vitamin B₁₂) or a placebo. Main Outcome Measures  The primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke, amputation of all or part of a lower extremity, a composite of these 3 plus all-cause mortality, time to initiation of dialysis, and time to thrombosis of arteriovenous access in hemodialysis patients. Results  Mean baseline homocysteine level was 24.0 µmol/L in the vitamin group and 24.2 µmol/L in the placebo group. It was lowered 6.3 µmol/L (25.8%; P < .001) in the vitamin group and 0.4 µmol/L (1.7%; P = .14) in the placebo group at 3 months, but there was no significant effect on mortality (448 vitamin group deaths vs 436 placebo group deaths) (hazard ratio [HR], 1.04; 95% CI, 0.91-1.18). No significant effects were demonstrated for secondary outcomes or adverse events: there were 129 MIs in the vitamin group vs 150 for placebo (HR, 0.86; 95% CI, 0.67-1.08), 37 strokes in the vitamin group vs 41 for placebo (HR, 0.90; 95% CI, 0.58-1.40), and 60 amputations in the vitamin group vs 53 for placebo (HR, 1.14; 95% CI, 0.79-1.64). In addition, the composite of MI, stroke, and amputations plus mortality (P = .85), time to dialysis (P = .38), and time to thrombosis in hemodialysis patients (P = .97) did not differ between the vitamin and placebo groups. Conclusion  Treatment with high doses of folic acid and B vitamins did not improve survival or reduce the incidence of vascular disease in patients with advanced chronic kidney disease or end-stage renal disease. Trial Registration  clinicaltrials.gov Identifier: NCT00032435      

Effects of ranolazine on recurrent cardiovascular events in patients with non-ST-elevation acute coronary syndromes: the MERLIN-TIMI 36 randomized trial

Context  Ranolazine is a novel antianginal agent that reduces ischemia in patients with chronic angina but has not been studied in patients with acute coronary syndromes (ACS). Objective  To determine the efficacy and safety of ranolazine during long-term treatment of patients with non–ST-elevation ACS. Design, Setting, and Patients  A randomized, double-blind, placebo-controlled, multinational clinical trial of 6560 patients within 48 hours of ischemic symptoms who were treated with ranolazine (initiated intravenously and followed by oral ranolazine extended-release 1000 mg twice daily, n = 3279) or matching placebo (n = 3281), and followed up for a median of 348 days in the Metabolic Efficiency With Ranolazine for Less Ischemia in Non–ST-Elevation Acute Coronary Syndromes (MERLIN)-TIMI 36 trial between October 8, 2004, and February 14, 2007. Main Outcome Measures  The primary efficacy end point was a composite of cardiovascular death, myocardial infarction (MI), or recurrent ischemia through the end of study. The major safety end points were death from any cause and symptomatic documented arrhythmia. Results  The primary end point occurred in 696 patients (21.8%) in the ranolazine group and 753 patients (23.5%) in the placebo group (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.83-1.02; P = .11). The major secondary end point (cardiovascular death, MI, or severe recurrent ischemia) occurred in 602 patients (18.7%) in the ranolazine group and 625 (19.2%) in the placebo group (HR, 0.96; 95% CI, 0.86-1.08; P = .50). Cardiovascular death or MI occurred in 338 patients (10.4%) allocated to ranolazine and 343 patients (10.5%) allocated to placebo (HR, 0.99; 95% CI, 0.85-1.15; P = .87). Recurrent ischemia was reduced in the ranolazine group (430 [13.9%]) compared with the placebo group (494 [16.1%]; HR, 0.87; 95% CI, 0.76-0.99; P = .03). QTc prolongation requiring a reduction in the dose of intravenous drug occurred in 31 patients (0.9%) receiving ranolazine compared with 10 patients (0.3%) receiving placebo. Symptomatic documented arrhythmias did not differ between the ranolazine (99 [3.0%]) and placebo (102 [3.1%]) groups (P = .84). No difference in total mortality was observed with ranolazine compared with placebo (172 vs 175; HR, 0.99; 95% CI, 0.80-1.22; P = .91). Conclusions  The addition of ranolazine to standard treatment for ACS was not effective in reducing major cardiovascular events. Ranolazine did not adversely affect the risk of all-cause death or symptomatic documented arrhythmia. Our findings provide support for the safety and efficacy of ranolazine as antianginal therapy. Trial Registration  clinicaltrials.gov Identifier: NCT00099788      

High-risk patients with acute coronary syndromes treated with low-molecular-weight or unfractionated heparin: outcomes at 6 months and 1 year in the SYNERGY trial

Context  The SYNERGY trial comparing enoxaparin and unfractionated heparin in high-risk patients with acute coronary syndromes (ACS) showed that enoxaparin was not inferior to unfractionated heparin in reducing death or nonfatal myocardial infarction (MI) at 30 days. Objective  To evaluate continued risk in this patient cohort through 6-month and 1-year follow-up. Design, Setting, and Patients  Overall, 9978 patients were randomized from August 2001 through December 2003 in 487 hospitals in 12 countries. Patients were followed up for 6 months and for 1 year. Main Outcome Measures  Six-month outcomes were death, nonfatal MI, revascularization procedures, stroke, and site-investigator–reported need for rehospitalization; 1-year outcome was all-cause death. Results  Six-month and 1-year follow-up data were available for 9957 (99.8%) and 9608 (96.3%) of 9978 patients, respectively; 541 patients (5.4%) had died at 6 months and 739 (7.4%) at 1 year. Death or nonfatal MI at 6 months occurred in 872 patients receiving enoxaparin (17.6%) vs 884 receiving unfractionated heparin (17.8%) (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.89-1.07; P = .65). In the subgroup of patients receiving consistent therapy, ie, only enoxaparin or unfractionated heparin during the index hospitalization (n = 6138), a reduction in death or nonfatal MI with enoxaparin was maintained at 180 days (HR, 0.85; 95% CI, 0.75-0.95; P = .006). Rehospitalization within 180 days occurred in 858 patients receiving enoxaparin (17.9%) and 911 receiving unfractionated heparin (19.0%) (HR, 0.94; 95% CI, 0.85-1.03; P = .17). One-year all-cause death rates were similar in the 2 treatment groups (380/4974 [7.6%] for enoxaparin vs 359/4948 [7.3%] for unfractionated heparin; HR, 1.06; 95% CI, 0.92-1.22; P = .44). One-year death rates in patients receiving consistent therapy were also similar (251/3386 [7.4%] for enoxaparin vs 213/2720 [7.8%] for unfractionated heparin; HR, 0.95; 95% CI, 0.79-1.14; P = .55). Conclusions  In the SYNERGY trial, patients continued to experience adverse cardiac events through long-term follow-up. The effect of enoxaparin on death or MI compared with that of unfractionated heparin at 6 months was similar to that observed at 30 days in the overall trial and in the consistent-therapy group. One-year death rates were also similar in both groups. High-risk patients with ACS remain susceptible to continued cardiac events despite aggressive therapies. ClinicalTrials.gov Identifier:  NCT00043784.      

High-dose atorvastatin vs usual-dose simvastatin for secondary prevention after myocardial infarction: the IDEAL study: a randomized controlled trial

Context  Evidence suggests that more intensive lowering of low-density lipoprotein cholesterol (LDL-C) than is commonly applied clinically will provide further benefit in stable coronary artery disease. Objective  To compare the effects of 2 strategies of lipid lowering on the risk of cardiovascular disease among patients with a previous myocardial infarction (MI). Design, Setting, and Participants  The IDEAL study, a prospective, randomized, open-label, blinded end-point evaluation trial conducted at 190 ambulatory cardiology care and specialist practices in northern Europe between March 1999 and March 2005 with a median follow-up of 4.8 years, which enrolled 8888 patients aged 80 years or younger with a history of acute MI. Interventions  Patients were randomly assigned to receive a high dose of atorvastatin (80 mg/d; n = 4439), or usual-dose simvastatin (20 mg/d; n = 4449). Main Outcome Measure  Occurrence of a major coronary event, defined as coronary death, confirmed nonfatal acute MI, or cardiac arrest with resuscitation. Results  During treatment, mean LDL-C levels were 104 (SE, 0.3) mg/dL in the simvastatin group and 81 (SE, 0.3) mg/dL in the atorvastatin group. A major coronary event occurred in 463 simvastatin patients (10.4%) and in 411 atorvastatin patients (9.3%) (hazard ratio [HR], 0.89; 95% CI, 0.78-1.01; P = .07). Nonfatal acute MI occurred in 321 (7.2%) and 267 (6.0%) in the 2 groups (HR, 0.83; 95% CI, 0.71-0.98; P = .02), but no differences were seen in the 2 other components of the primary end point. Major cardiovascular events occurred in 608 and 533 in the 2 groups, respectively (HR, 0.87; 95% CI, 0.77-0.98; P = .02). Occurrence of any coronary event was reported in 1059 simvastatin and 898 atorvastatin patients (HR, 0.84; 95% CI, 0.76-0.91; P<.001). Noncardiovascular death occurred in 156 (3.5%) and 143 (3.2%) in the 2 groups (HR, 0.92; 95% CI, 0.73-1.15; P = .47). Death from any cause occurred in 374 (8.4%) in the simvastatin group and 366 (8.2%) in the atorvastatin group (HR, 0.98; 95% CI, 0.85-1.13; P = .81). Patients in the atorvastatin group had higher rates of drug discontinuation due to nonserious adverse events; transaminase elevation resulted in 43 (1.0%) vs 5 (0.1%) withdrawals (P<.001). Serious myopathy and rhabdomyolysis were rare in both groups. Conclusions  In this study of patients with previous MI, intensive lowering of LDL-C did not result in a significant reduction in the primary outcome of major coronary events, but did reduce the risk of other composite secondary end points and nonfatal acute MI. There were no differences in cardiovascular or all-cause mortality. Patients with MI may benefit from intensive lowering of LDL-C without an increase in noncardiovascular mortality or other serious adverse reactions. Trial Registration  ClinicalTrials.gov Identifier: NCT00159835.      

Vitamin E in the primary prevention of cardiovascular disease and cancer: the Women's Health Study: a randomized controlled trial

Context  Basic research provides plausible mechanisms and observational studies suggest that apparently healthy persons, who self-select for high intakes of vitamin E through diet or supplements, have decreased risks of cardiovascular disease and cancer. Randomized trials do not generally support benefits of vitamin E, but there are few trials of long duration among initially healthy persons. Objective  To test whether vitamin E supplementation decreases risks of cardiovascular disease and cancer among healthy women. Design, Setting, and Participants  In the Women’s Health Study conducted between 1992 and 2004, 39 876 apparently healthy US women aged at least 45 years were randomly assigned to receive vitamin E or placebo and aspirin or placebo, using a 2 x 2 factorial design, and were followed up for an average of 10.1 years. Intervention  Administration of 600 IU of natural-source vitamin E on alternate days. Main Outcome Measures  Primary outcomes were a composite end point of first major cardiovascular event (nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death) and total invasive cancer. Results  During follow-up, there were 482 major cardiovascular events in the vitamin E group and 517 in the placebo group, a nonsignificant 7% risk reduction (relative risk [RR], 0.93; 95% confidence interval [CI], 0.82-1.05; P = .26). There were no significant effects on the incidences of myocardial infarction (RR,  1.01; 95% CI, 0.82-1.23; P = .96) or stroke (RR, 0.98; 95% CI, 0.82-1.17; P = .82), as well as ischemic or hemorrhagic stroke. For cardiovascular death, there was a significant 24% reduction (RR, 0.76; 95% CI, 0.59-0.98; P = .03). There was no significant effect on the incidences of total cancer (1437 cases in the vitamin E group and 1428 in the placebo group; RR, 1.01; 95% CI, 0.94-1.08; P = .87) or breast (RR, 1.00; 95% CI, 0.90-1.12; P = .95), lung (RR, 1.09; 95% CI, 0.83-1.44; P = .52), or colon cancers (RR, 1.00; 95% CI, 0.77-1.31; P = .99). Cancer deaths also did not differ significantly between groups. There was no significant effect of vitamin E on total mortality (636 in the vitamin E group and 615 in the placebo group; RR, 1.04; 95% CI, 0.93-1.16; P = .53). Conclusions  The data from this large trial indicated that 600 IU of natural-source vitamin E taken every other day provided no overall benefit for major cardiovascular events or cancer, did not affect total mortality, and decreased cardiovascular mortality in healthy women. These data do not support recommending vitamin E supplementation for cardiovascular disease or cancer prevention among healthy women.      

Effects of reviparin, a low-molecular-weight heparin, on mortality, reinfarction, and strokes in patients with acute myocardial infarction presenting with ST-segment elevation

Context  Although reperfusion therapy, aspirin, -blockers, and angiotensin-converting enzyme inhibitors reduce mortality when used early in patients with acute myocardial infarction (MI), mortality and morbidity remain high. No antithrombotic or newer antiplatelet drug has been shown to reduce mortality in acute MI. Objective  To evaluate the effects of reviparin, a low-molecular-weight heparin, when initiated early and given for 7 days in addition to usual therapy on the primary composite outcome of death, myocardial reinfarction, or strokes at 7 and 30 days. Design, Setting, and Patients  A randomized, double-blind, placebo-controlled trial (Clinical Trial of Reviparin and Metabolic Modulation in Acute Myocardial Infarction Treatment Evaluation [CREATE]) of 15 570 patients with ST-segment elevation or new left bundle-branch block, presenting within 12 hours of symptom onset at 341 hospitals in India and China from July 2001 through July 2004. Intervention  Reviparin or placebo subcutaneously twice daily for 7 days. Main Outcome Measure  Primary composite outcome of death, myocardial reinfarction, or stroke at 7 and 30 days. Results  The primary composite outcome was significantly reduced from 854 (11.0%) of 7790 patients in the placebo group to 745 (9.6%) of 7780 in the reviparin group (hazard ratio [HR], 0.87; 95% CI, 0.79-0.96; P = .005). These benefits persisted at 30 days (1056 [13.6%] vs 921 [11.8%] patients; HR, 0.87; 95% CI, 0.79-0.95; P = .001) with significant reductions in 30-day mortality (877 [11.3%] vs 766 [9.8%]; HR, 0.87; 95% CI, 0.79-0.96; P = .005) and reinfarction (199 [2.6%] vs 154 [2.0%]; HR, 0.77; 95% CI, 0.62-0.95; P = .01), and no significant differences in strokes (64 [0.8%] vs 80 [1.0%]; P = .19). Reviparin treatment was significantly better when it was initiated very early after symptom onset at 7 days (<2 hours: HR, 0.70; 95% CI, 0.52-0.96; P = .03; 30/1000 events prevented; 2 to <4 hours: HR, 0.81; 95% CI, 0.67-0.98; P = .03; 21/1000 events prevented; 4 to <8 hours: HR, 0.85; 95% CI, 0.73-0.99; P = .05; 16/1000 events prevented; and 8 hours: HR, 1.06; 95% CI, 0.86-1.30; P = .58; P = .04 for trend). There was an increase in life-threatening bleeding at 7 days with reviparin and placebo (17 [0.2%] vs 7 [0.1%], respectively; P = .07), but the absolute excess was small (1 more per 1000) vs reductions in the primary outcome (18 fewer per 1000) or mortality (15 fewer per 1000). Conclusions  In patients with acute ST-segment elevation or new left bundle-branch block MI, reviparin reduces mortality and reinfarction, without a substantive increase in overall stroke rates. There is a small absolute excess of life-threatening bleeding but the benefits outweigh the risks.      

Effect of folic acid and B vitamins on risk of cardiovascular events and total mortality among women at high risk for cardiovascular disease: a randomized trial

Christine M. Albert, MD, MPH; Nancy R. Cook, ScD; J. Michael Gaziano, MD, MPH; Elaine Zaharris, BA; Jean MacFadyen, BA; Eleanor Danielson, MIA; Julie E. Buring, ScD; JoAnn E. Manson, MD, DrPH

JAMA. 2008;299(17):2027-2036.

Context  Recent randomized trials among patients with preexisting cardiovascular disease (CVD) have failed to support benefits of B-vitamin supplementation on cardiovascular risk. Observational data suggest benefits may be greater among women, yet women have been underrepresented in published randomized trials.

Objective  To test whether a combination of folic acid, vitamin B₆, and vitamin B₁₂ lowers risk of CVD among high-risk women with and without CVD.

Design, Setting, and Participants  Within an ongoing randomized trial of antioxidant vitamins, 5442 women who were US health professionals aged 42 years or older, with either a history of CVD or 3 or more coronary risk factors, were enrolled in a randomized, double-blind, placebo-controlled trial to receive a combination pill containing folic acid, vitamin B₆, and vitamin B₁₂ or a matching placebo, and were treated for 7.3 years from April 1998 through July 2005.

Intervention  Daily intake of a combination pill of 2.5 mg of folic acid, 50 mg of vitamin B₆, and 1 mg of vitamin B₁₂.

Main Outcome Measures  A composite outcome of myocardial infarction, stroke, coronary revascularization, or CVD mortality.

Results  Compared with placebo, a total of 796 women experienced a confirmed CVD event (406 in the active group and 390 in the placebo group). Patients receiving active vitamin treatment had similar risk for the composite CVD primary end point (226.9/10 000 person-years vs 219.2/10 000 person-years for the active vs placebo group; relative risk [RR], 1.03; 95% confidence interval [CI], 0.90-1.19; P = .65), as well as for the secondary outcomes including myocardial infarction (34.5/10 000 person-years vs 39.5/10 000 person-years; RR, 0.87; 95% CI, 0.63-1.22; P = .42), stroke (41.9/10 000 person-years vs 36.8/10 000 person-years; RR, 1.14; 95% CI, 0.82-1.57; P = .44), and CVD mortality (50.3/10 000 person-years vs 49.6/10 000 person-years; RR, 1.01; 95% CI, 0.76-1.35; P = .93). In a blood substudy, geometric mean plasma homocysteine level was decreased by 18.5% (95% CI, 12.5%-24.1%; P < .001) in the active group (n = 150) over that observed in the placebo group (n = 150), for a difference of 2.27 µmol/L (95% CI, 1.54-2.96 µmol/L).

Conclusion  After 7.3 years of treatment and follow-up, a combination pill of folic acid, vitamin B₆, and vitamin B₁₂ did not reduce a combined end point of total cardiovascular events among high-risk women, despite significant homocysteine lowering.

Trial Registration  clinicaltrials.gov Identifier: NCT00000541

     

Effects of fondaparinux on mortality and reinfarction in patients with acute ST-segment elevation myocardial infarction: the OASIS-6 randomized trial

Context  Despite many therapeutic advances, mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) remains high. The role of additional antithrombotic agents is unclear, especially among patients not receiving reperfusion therapy. Objective  To evaluate the effect of fondaparinux, a factor Xa inhibitor, when initiated early and given for up to 8 days vs usual care (placebo in those in whom unfractionated heparin [UFH] is not indicated [stratum 1] or unfractionated heparin for up to 48 hours followed by placebo for up to 8 days [stratum 2]) in patients with STEMI. Design, Setting, and Participants  Randomized double-blind comparison of fondaparinux 2.5 mg once daily or control for up to 8 days in 12 092 patients with STEMI from 447 hospitals in 41 countries (September 2003-January 2006). From day 3 through day 9, all patients received either fondaparinux or placebo according to the original randomized assignment. Main Outcome Measures  Composite of death or reinfarction at 30 days (primary) with secondary assessments at 9 days and at final follow-up (3 or 6 months). Results  Death or reinfarction at 30 days was significantly reduced from 677 (11.2%) of 6056 patients in the control group to 585 (9.7%) of 6036 patients in the fondaparinux group (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.77-0.96; P = .008); absolute risk reduction, 1.5%; 95% CI, 0.4%-2.6%). These benefits were observed at 9 days (537 [8.9%] placebo vs 444 [7.4%] fondaparinux; HR, 0.83; 95% CI, 0.73-0.94; P = .003, and at study end (857 [14.8%] placebo vs 756 [13.4%] fondaparinux; HR, 0.88; 95% CI, 0.79-0.97; P = .008). Mortality was significantly reduced throughout the study. There was no heterogeneity of the effects of fondaparinux in the 2 strata by planned heparin use. However, there was no benefit in those undergoing primary percutaneous coronary intervention. In other patients in stratum 2, fondaparinux was superior to unfractionated heparin in preventing death or reinfarction at 30 days (HR, 0.82; 95% CI, 0.66-1.02; P = .08) and at study end (HR, 0.77; 95% CI, 0.64-0.93; P = .008). Significant benefits were observed in those receiving thrombolytic therapy (HR, 0.79; P = .003) and those not receiving any reperfusion therapy (HR, 0.80; P = .03). There was a tendency to fewer severe bleeds (79 for placebo vs 61 for fondaparinux; P = .13), with significantly fewer cardiac tamponade (48 vs 28; P = .02) with fondaparinux at 9 days. Conclusion  In patients with STEMI, particularly those not undergoing primary percutaneous coronary intervention, fondaparinux significantly reduces mortality and reinfarction without increasing bleeding and strokes. Trial Registration  ClinicalTrials.gov Identifier NCT00064428      

Effect of antihypertensive agents on cardiovascular events in patients with coronary disease and normal blood pressure: the CAMELOT study: a randomized controlled trial

Context  The effect of antihypertensive drugs on cardiovascular events in patients with coronary artery disease (CAD) and normal blood pressure remains uncertain. Objective  To compare the effects of amlodipine or enalapril vs placebo on cardiovascular events in patients with CAD. Design, Setting, and Participants  Double-blind, randomized, multicenter, 24-month trial (enrollment April 1999-April 2002) comparing amlodipine or enalapril with placebo in 1991 patients with angiographically documented CAD (>20% stenosis by coronary angiography) and diastolic blood pressure <100 mm Hg. A substudy of 274 patients measured atherosclerosis progression by intravascular ultrasound (IVUS). Interventions  Patients were randomized to receive amlodipine, 10 mg; enalapril, 20 mg; or placebo. IVUS was performed at baseline and study completion. Main Outcome Measures  The primary efficacy parameter was incidence of cardiovascular events for amlodipine vs placebo. Other outcomes included comparisons of amlodipine vs enalapril and enalapril vs placebo. Events included cardiovascular death, nonfatal myocardial infarction, resuscitated cardiac arrest, coronary revascularization, hospitalization for angina pectoris, hospitalization for congestive heart failure, fatal or nonfatal stroke or transient ischemic attack, and new diagnosis of peripheral vascular disease. The IVUS end point was change in percent atheroma volume. Results  Baseline blood pressure averaged 129/78 mm Hg for all patients; it increased by 0.7/0.6 mm Hg in the placebo group and decreased by 4.8/2.5 mm Hg and 4.9/2.4 mm Hg in the amlodipine and enalapril groups, respectively (P<.001 for both vs placebo). Cardiovascular events occurred in 151 (23.1%) placebo-treated patients, in 110 (16.6%) amlodipine-treated patients (hazard ratio [HR], 0.69; 95% CI, 0.54-0.88 [P = .003]), and in 136 (20.2%) enalapril-treated patients (HR, 0.85; 95% CI, 0.67-1.07 [P = .16]. Primary end point comparison for enalapril vs amlodipine was not significant (HR, 0.81; 95% CI, 0.63-1.04 [P = .10]). The IVUS substudy showed a trend toward less progression of atherosclerosis in the amlodipine group vs placebo (P = .12), with significantly less progression in the subgroup with systolic blood pressures greater than the mean (P = .02). Compared with baseline, IVUS showed progression in the placebo group (P<.001), a trend toward progression in the enalapril group (P = .08), and no progression in the amlodipine group (P = .31). For the amlodipine group, correlation between blood pressure reduction and progression was r = 0.19, P = .07. Conclusions  Administration of amlodipine to patients with CAD and normal blood pressure resulted in reduced adverse cardiovascular events. Directionally similar, but smaller and nonsignificant, treatment effects were observed with enalapril. For amlodipine, IVUS showed evidence of slowing of atherosclerosis progression.      

Hormone replacement therapy and incidence of Alzheimer disease in older women: the Cache County Study

Context  Previous studies have shown a sex-specific increased risk of Alzheimer disease (AD) in women older than 80 years. Basic neuroscience findings suggest that hormone replacement therapy (HRT) could reduce a woman's risk of AD. Epidemiologic findings on AD and HRT are mixed. Objective  To examine the relationship between use of HRT and risk of AD among elderly women. Design, Setting, and Participants  Prospective study of incident dementia among 1357 men (mean age, 73.2 years) and 1889 women (mean age, 74.5 years) residing in a single county in Utah. Participants were first assessed in 1995-1997, with follow-up conducted in 1998-2000. History of women's current and former use of HRT, as well as of calcium and multivitamin supplements, was ascertained at the initial contact. Main Outcome Measure  Diagnosis of incident AD. Results  Thirty-five men (2.6%) and 88 women (4.7%) developed AD between the initial interview and time of the follow-up (3 years). Incidence among women increased after age 80 years and exceeded the risk among men of similar age (adjusted hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.22-3.86). Women who used HRT had a reduced risk of AD (26 cases among 1066 women) compared with non-HRT users (58 cases among 800 women) (adjusted HR, 0.59; 95% CI, 0.36-0.96). Risk varied with duration of HRT use, so that a woman's sex-specific increase in risk disappeared entirely with more than 10 years of treatment (7 cases among 427 women). Adjusted HRs were 0.41 (95% CI, 0.17-0.86) for HRT users compared with nonusers and 0.77 (95% CI, 0.31-1.67) compared with men. No similar effect was seen with calcium or multivitamin use. Almost all of the HRT-related reduction in incidence reflected former use of HRT (9 cases among 490 women; adjusted HR, 0.33 [95% CI, 0.15-0.65]). There was no effect with current HRT use (17 cases among 576 women; adjusted HR, 1.08 [95% CI, 0.59-1.91]) unless duration of treatment exceeded 10 years (6 cases among 344 women; adjusted HR, 0.55 [95% CI, 0.21-1.23]). Conclusions  Prior HRT use is associated with reduced risk of AD, but there is no apparent benefit with current HRT use unless such use has exceeded 10 years.      

Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials

Context  The role and dose of oral vitamin D supplementation in nonvertebral fracture prevention have not been well established. Objective  To estimate the effectiveness of vitamin D supplementation in preventing hip and nonvertebral fractures in older persons. Data Sources  A systematic review of English and non-English articles using MEDLINE and the Cochrane Controlled Trials Register (1960-2005), and EMBASE (1991-2005). Additional studies were identified by contacting clinical experts and searching bibliographies and abstracts presented at the American Society for Bone and Mineral Research (1995-2004). Search terms included randomized controlled trial (RCT), controlled clinical trial, random allocation, double-blind method, cholecalciferol, ergocalciferol, 25-hydroxyvitamin D, fractures, humans, elderly, falls, and bone density. Study Selection  Only double-blind RCTs of oral vitamin D supplementation (cholecalciferol, ergocalciferol) with or without calcium supplementation vs calcium supplementation or placebo in older persons (60 years) that examined hip or nonvertebral fractures were included. Data Extraction  Independent extraction of articles by 2 authors using predefined data fields, including study quality indicators. Data Synthesis  All pooled analyses were based on random-effects models. Five RCTs for hip fracture (n = 9294) and 7 RCTs for nonvertebral fracture risk (n = 9820) met our inclusion criteria. All trials used cholecalciferol. Heterogeneity among studies for both hip and nonvertebral fracture prevention was observed, which disappeared after pooling RCTs with low-dose (400 IU/d) and higher-dose vitamin D (700-800 IU/d), separately. A vitamin D dose of 700 to 800 IU/d reduced the relative risk (RR) of hip fracture by 26% (3 RCTs with 5572 persons; pooled RR, 0.74; 95% confidence interval [CI], 0.61-0.88) and any nonvertebral fracture by 23% (5 RCTs with 6098 persons; pooled RR, 0.77; 95% CI, 0.68-0.87) vs calcium or placebo. No significant benefit was observed for RCTs with 400 IU/d vitamin D (2 RCTs with 3722 persons; pooled RR for hip fracture, 1.15; 95% CI, 0.88-1.50; and pooled RR for any nonvertebral fracture, 1.03; 95% CI, 0.86-1.24). Conclusions  Oral vitamin D supplementation between 700 to 800 IU/d appears to reduce the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/d is not sufficient for fracture prevention.      

Postmenopausal hormone therapy and risk of cardiovascular disease by age and years since menopause

Context  The timing of initiation of hormone therapy may influence its effect on cardiovascular disease. Objective  To explore whether the effects of hormone therapy on risk of cardiovascular disease vary by age or years since menopause began. Design, Setting, and Participants  Secondary analysis of the Women's Health Initiative (WHI) randomized controlled trials of hormone therapy in which 10 739 postmenopausal women who had undergone a hysterectomy were randomized to conjugated equine estrogens (CEE) or placebo and 16 608 postmenopausal women who had not had a hysterectomy were randomized to CEE plus medroxyprogesterone acetate (CEE + MPA) or placebo. Women aged 50 to 79 years were recruited to the study from 40 US clinical centers between September 1993 and October 1998. Main Outcome Measures  Statistical test for trend of the effect of hormone therapy on coronary heart disease (CHD) and stroke across categories of age and years since menopause in the combined trials. Results  In the combined trials, there were 396 cases of CHD and 327 cases of stroke in the hormone therapy group vs 379 cases of CHD and 239 cases of stroke in the placebo group. For women with less than 10 years since menopause began, the hazard ratio (HR) for CHD was 0.76 (95% confidence interval [CI], 0.50-1.16); 10 to 19 years, 1.10 (95% CI, 0.84-1.45); and 20 or more years, 1.28 (95% CI, 1.03-1.58) (P for trend = .02). The estimated absolute excess risk for CHD for women within 10 years of menopause was –6 per 10 000 person-years; for women 10 to 19 years since menopause began, 4 per 10 000 person-years; and for women 20 or more years from menopause onset, 17 per 10 000 person-years. For the age group of 50 to 59 years, the HR for CHD was 0.93 (95% CI, 0.65-1.33) and the absolute excess risk was –2 per 10 000 person-years; 60 to 69 years, 0.98 (95% CI, 0.79-1.21) and –1 per 10 000 person-years; and 70 to 79 years, 1.26 (95% CI, 1.00-1.59) and 19 per 10 000 person-years (P for trend = .16). Hormone therapy increased the risk of stroke (HR, 1.32; 95% CI, 1.12-1.56). Risk did not vary significantly by age or time since menopause. There was a nonsignificant tendency for the effects of hormone therapy on total mortality to be more favorable in younger than older women (HR of 0.70 for 50-59 years; 1.05 for 60-69 years, and 1.14 for 70-79 years; P for trend = .06). Conclusions  Women who initiated hormone therapy closer to menopause tended to have reduced CHD risk compared with the increase in CHD risk among women more distant from menopause, but this trend test did not meet our criterion for statistical significance. A similar nonsignificant trend was observed for total mortality but the risk of stroke was elevated regardless of years since menopause. These data should be considered in regard to the short-term treatment of menopausal symptoms. Trial Registration  clinicaltrials.gov Identifier: NCT00000611      

Long-term efficacy of platelet glycoprotein IIb/IIIa integrin blockade with eptifibatide in coronary stent intervention

Context  In the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial, treatment with eptifibatide, a platelet glycoprotein IIb/IIIa integrin blocker, was found to reduce the ischemic complications of nonurgent coronary stent implantation at 48 hours and 30 days. Objective  To determine whether eptifibatide treatment continues to provide durable, long-term benefit after coronary stent intervention. Design and Setting  The ESPRIT trial was a randomized, double-blind, placebo-controlled, parallel-group, crossover-permitted trial conducted from June 1999 through February 2000 at 92 tertiary care centers in the United States and Canada. Participants  A total of 2064 patients scheduled to undergo nonurgent percutaneous coronary intervention with stent implantation. Intervention  Patients were randomly assigned to receive placebo (n = 1024) or eptifibatide (two 180-µg/kg boluses, 10 minutes apart, with a continuous infusion of 2.0 µg/kg per minute; n = 1040), started immediately before stent implantation and continued for 18 to 24 hours. Patients also received aspirin, heparin, and a thienopyridine. Main Outcome Measures  Composite rates of death or myocardial infarction (MI) and death, infarction, or target vessel revascularization during the 12 months after enrollment. Results  Complete follow-up data were available for 988 patients given eptifibatide (95.0%) and 976 patients given placebo (95.3%). By 12 months, the composite of death or MI had occurred in 8.0% of eptifibatide-treated patients and in 12.4% of placebo-treated patients (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.48-0.83; P = .001). The composite rate of death, MI, or target vessel revascularization was 17.5% in eptifibatide-treated patients vs 22.1% in placebo-treated patients (HR, 0.76; 95% CI, 0.63-0.93; P = .007). Conclusions  Long-term outcomes of nonurgent coronary stent implantation appear to be improved through blockade of the platelet glycoprotein IIb/IIIa integrin with eptifibatide.      

Effects of conjugated equine estrogens on breast cancer and mammography screening in postmenopausal women with hysterectomy

Context  The Women's Health Initiative Estrogen-Aone trial comparing conjugated equine estrogens (CEE) with placebo was stopped early because of an increased stroke incidence and no reduction in risk of coronary heart disease. Preliminary results suggesting possible reduction in breast cancers warranted more detailed analysis. Objective  To determine the effects of CEE on breast cancers and mammographic findings. Design, Setting, and Participants  Following breast cancer risk assessment, 10 739 postmenopausal women aged 50 to 79 years with prior hysterectomy were randomized to CEE or placebo at 40 US clinical centers from 1993 through 1998. Mammography screenings and clinical breast examinations were performed at baseline and annually. All breast cancers diagnosed through February 29, 2004, are included. Intervention  A dose of 0.625 mg/d of CEE or an identical-appearing placebo. Main Outcome Measures  Breast cancer incidence, tumor characteristics, and mammogram findings. Results  After a mean (SD) follow-up of 7.1 (1.6) years, the invasive breast cancer hazard ratio (HR) for women assigned to CEE vs placebo was 0.80 (95% confidence interval [CI], 0.62-1.04; P = .09) with annualized rates of 0.28% (104 cases in the CEE group) and 0.34% (133 cases in the placebo group). In exploratory analyses, ductal carcinomas (HR, 0.71; 95% CI, 0.52-0.99) were reduced in the CEE group vs placebo group; however, the test for interaction by tumor type was not significant (P = .054). At 1 year, 9.2% of women in the CEE group had mammograms with abnormalities requiring follow-up vs 5.5% in the placebo group (P<.001), a pattern that continued through the trial to reach a cumulative percentage of 36.2% vs 28.1%, respectively (P<.001); however, this difference was primarily in assessments requiring short interval follow-up. Conclusions  Treatment with CEE alone for 7.1 years does not increase breast cancer incidence in postmenopausal women with prior hysterectomy. However, treatment with CEE increases the frequency of mammography screening requiring short interval follow-up. Initiation of CEE should be based on consideration of the individual woman's potential risks and benefits. Trial Registration  clinicaltrials.gov Identifier: NCT00000611      

Conjugated equine estrogens and incidence of probable dementia and mild cognitive impairment in postmenopausal women: Women's Health Initiative Memory Study

Context  The Women's Health Initiative Memory Study (WHIMS) previously found increased risk for dementia and no effect on mild cognitive impairment (MCI) in women treated with conjugated equine estrogens (CEE) plus medroxyprogesterone acetate (MPA). Objective  To determine the effects of CEE alone and CEE plus MPA on incidence of probable dementia and MCI in older women. Design, Setting, and Participants  Randomized, double-blind, placebo-controlled clinical trials of CEE (estrogen-alone trial) or CEE plus MPA (estrogen plus progestin trial) in community-dwelling women aged 65 to 79 years, conducted from June 1995 to July 8, 2002 (estrogen plus progestin; n = 4532), or to February 29, 2004 (estrogen-alone; n = 2947), in 39 of the 40 WHI clinical centers. Interventions  In the estrogen-alone trial, 1 daily tablet containing either 0.625 mg/d of CEE vs matching placebo; in the estrogen plus progestin trial, 1 daily tablet containing CEE (0.625 mg/d) plus MPA (2.5 mg/d) vs matching placebos. Main Outcome Measures  Probable dementia and MCI. Results  In the estrogen-alone trial, 47 participants were diagnosed with probable dementia, of whom 28 were assigned to CEE and 19 to placebo (hazard ratio [HR], 1.49; 95% confidence interval [CI], 0.83-2.66). Incidence rates for probable dementia in the estrogen-alone trial were statistically similar to those in the estrogen plus progestin trial (45 vs 22 per 10 000 person-years for CEE plus MPA vs placebo, respectively; P = .11). When data were pooled per the original WHIMS protocol, the overall HR for probable dementia was 1.76 (95% CI, 1.19-2.60; P = .005). After excluding participants with baseline Modified Mini-Mental State Examination scores at or below the screening cut point, the HR was 1.77 (95% CI, 0.74-4.23; P = .20) in the estrogen-alone trial and 2.19 (95% CI, 1.25-3.84; P = .006) in the pooled trials. In the estrogen-alone trial, 76 participants were diagnosed with MCI in the CEE group vs 58 in the placebo group (HR, 1.34; 95% CI, 0.95-1.89). In the combined trial data, the HR was similar (1.25; 95% CI, 0.97-1.60). In the estrogen-alone trial, 93 participants receiving CEE were diagnosed with either probable dementia or MCI vs 69 receiving placebo (HR, 1.38; 95% CI, 1.01-1.89; P = .04). Conclusions  Estrogen therapy alone did not reduce dementia or MCI incidence and increased the risk for both end points combined. Pooling data for estrogen alone and estrogen plus progestin resulted in increased risks for both end points. Use of hormone therapy to prevent dementia or cognitive decline in women 65 years of age or older is not recommended.      

Regression of electrocardiographic left ventricular hypertrophy during antihypertensive treatment and the prediction of major cardiovascular events

Context  Electrocardiographic left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular (CV) morbidity and mortality. However, the predictive value of changes in the magnitude of electrocardiographic LVH criteria during antihypertensive therapy remains unclear. Objective  To test the hypothesis that lesser severity of electrocardiographic LVH during antihypertensive treatment is associated with decreased CV morbidity and mortality, independent of blood pressure levels and reduction and treatment modality. Design, Setting, and Participants  Double-blind, randomized, parallel-group study conducted in 1995-2001 among 9193 men and women with hypertension aged 55 through 80 years (mean, 67 years), with electrocardiographic LVH by Cornell voltage-duration product or Sokolow-Lyon voltage criteria and enrolled in the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) study. Interventions  Losartan- or atenolol-based treatment regimens, with follow-up assessments for at least 4 (mean, 4.8 [SD, 0.9]) years. Main Outcome Measure  Composite end point of CV death, myocardial infarction (MI), or stroke in relation to severity of electrocardiographic LVH determined at baseline and on subsequent electrocardiograms obtained at 1 or more annual revisits. Results  Cardiovascular death, nonfatal MI, or stroke occurred in 1096 patients (11.9%). In Cox regression models controlling for treatment type, baseline Framingham risk score, baseline and in-treatment blood pressure, and severity of baseline electrocardiographic LVH by Cornell product and Sokolow-Lyon voltage, less-severe in-treatment LVH by Cornell product and Sokolow-Lyon voltage were associated with 14% and 17% lower rates, respectively, of the composite CV end point (adjusted hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.82-0.90; P<.001 for every 1050-mm x ms [1-SD] decrease in Cornell product; and HR, 0.83; 95% CI, 0.78-0.88; P<.001 for every 10.5-mm [1-SD] decrease in Sokolow-Lyon voltage). In parallel analyses, lower Cornell product and Sokolow-Lyon voltage were each independently associated with lower risks of CV mortality (HR, 0.78; 95% CI, 0.73-0.83; P<.001; and HR, 0.80; 95% CI, 0.73-0.87; P<.001, respectively), MI (HR, 0.90; 95% CI, 0.82-0.98; P=.01; and HR, 0.90; 95% CI, 0.81-1.00; P = .04), and stroke (HR, 0.90; 95% CI, 0.84-0.96; P=.002; and HR, 0.81; 95% CI, 0.75-0.89; P<.001). Conclusions  Less-severe electrocardiographic LVH by Cornell product and Sokolow-Lyon voltage criteria during antihypertensive therapy is associated with lower likelihoods of CV morbidity and mortality, independent of blood pressure lowering and treatment modality in persons with essential hypertension. Antihypertensive therapy targeted at regression or prevention of electrocardiographic LVH may improve prognosis.      

Effects of a 5-lipoxygenase-activating protein inhibitor on biomarkers associated with risk of myocardial infarction: a randomized trial

Context  Myocardial infarction (MI) is the leading cause of death in the world. Variants in the 5-lipoxygenase–activating protein (FLAP) gene are associated with risk of MI. Objective  To determine the effect of an inhibitor of FLAP on levels of biomarkers associated with MI risk. Design, Setting, and Patients  A randomized, prospective, placebo-controlled, crossover trial of an inhibitor of FLAP (DG-031) in MI patients who carry at-risk variants in the FLAP gene or in the leukotriene A₄ hydrolase gene. Of 268 patients screened, 191 were carriers of at-risk variants in FLAP (87%) or leukotriene A₄ hydrolase (13%). Individuals were enrolled in April 2004 and were followed up by designated cardiologists from a university hospital in Iceland until September 2004. Interventions  Patients were first randomized to receive 250 mg/d of DG-031, 500 mg/d of DG-031, 750 mg/d of DG-031, or placebo. After a 2-week washout period, patients received DG-031 if they had received placebo first or placebo if they had received DG-031 first. Treatment periods lasted for 4 weeks. Main Outcome Measures  Changes in levels of biomarkers associated with risk of MI. Results  In response to 750 mg/d of DG-031, production of leukotriene B₄ was significantly reduced by 26% (95% confidence interval [CI], 10%-39%; P = .003) and myeloperoxidase was significantly reduced by 12% (95% CI, 2%-21%; P = .02). The higher 2 doses of DG-031 produced a nonsignificant reduction in C-reactive protein (16%; 95% CI, –2% to 31%; P = .07) at 2 weeks. However, there was a more pronounced reduction (25%; 95% CI, 5%-40%; P = .02) in C-reactive protein at the end of the washout period that persisted for another 4 weeks thereafter. The FLAP inhibitor DG-031 was well tolerated and was not associated with any serious adverse events. Conclusion  In patients with specific at-risk variants of 2 genes in the leukotriene pathway, DG-031 led to significant and dose-dependent suppression of biomarkers that are associated with increased risk of MI events.      

Prophylactic Oral Amiodarone for the Prevention of Arrhythmias that Begin Early After Revascularization, Valve Replacement, or Repair: PAPABEAR: a randomized controlled trial

Context  Atrial tachyarrhythmias after cardiac surgery are associated with adverse outcomes and increased costs. Previous trials of amiodarone prophylaxis, while promising, were relatively small and yielded conflicting results. Objective  To determine whether a brief perioperative course of oral amiodarone is an effective and safe prophylaxis for atrial tachyarrhythmias after cardiac surgery overall and in important subgroups. Design, Setting, and Patients  Double-blind randomized controlled trial of 601 patients listed for nonemergent coronary artery bypass graft (CABG) surgery and/or valve replacement/repair surgery between February 1, 1999, and September 26, 2003, at a tertiary care hospital. The patients were followed up for 1 year. Intervention  Oral amiodarone (10 mg/kg daily) or placebo administered 6 days prior to surgery through 6 days after surgery (13 days). Randomization was stratified for subgroups defined by age, type of surgery, and use of preoperative -blockers. Main Outcome Measure  Incidence of atrial tachyarrhythmias lasting 5 minutes or longer that prompted therapy by the sixth postoperative day. Results  Atrial tachyarrhythmias occurred in fewer amiodarone patients (48/299; 16.1%) than in placebo patients (89/302; 29.5%) overall (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.34-0.69; P<.001); in patients younger than 65 years (19 [11.2%] vs 36 [21.1%]; HR, 0.51 [95% CI, 0.28-0.94]; P = .02); in patients aged 65 years or older (28 [21.7%] vs 54 [41.2%]; HR, 0.45 [95% CI, 0.27-0.75]; P<.001); in patients who had CABG surgery only (22 [11.3%] vs 46 [23.6%]; HR, 0.45 [95% CI, 0.26-0.79]; P = .002); in patients who had valve replacement/repair surgery with or without CABG surgery (25 [23.8%] vs 44 [44.1%]; HR, 0.51 [95% CI, 0.31-0.84; P = .008); in patients who received preoperative -blocker therapy (27 [15.3%] vs 42 [25.0%]; HR, 0.58 [95% CI, 0.34-0.99]; P = .03); and in patients who did not receive preoperative -blocker therapy (20 [16.3%] vs 48 [35.8%]; HR, 0.40 [95% CI, 0.22-0.71]; P<.001), respectively. Postoperative sustained ventricular tachyarrhythmias occurred less frequently in amiodarone patients (1/299; 0.3%) than in placebo patients (8/302; 2.6%) (P = .04). Dosage reductions of blinded therapy were more common in amiodarone patients (34/299; 11.4%) than in placebo patients (16/302; 5.3%) (P = .008). There were no differences in serious postoperative complications, in-hospital mortality, or readmission to the hospital within 6 months of discharge or in 1-year mortality. Conclusion  Oral amiodarone prophylaxis of atrial tachyarrhythmias after cardiac surgery is effective and may be safe overall and in important patient subgroups. Clinical Trials Registration  ClinicalTrials.gov Identifier: NCT00251706      

Association between estrogen receptor alpha gene variation and cardiovascular disease

Context  Estrogen and related hormone therapies activate estrogen receptors, which in turn regulate genes for several cardiovascular disease (CVD) risk factors. Relatively little is known, however, about the impact of genetic variation in estrogen receptor (ESR1) on CVD risk. Objective  To investigate whether the ESR1 c.454-397T>C polymorphism is associated with CVD risk. Design, Setting, and Participants  Prospective study of 1739 unrelated men and women from the population-based offspring cohort of the Framingham Heart Study, who were followed up from 1971 to 1998. Main Outcome Measures  Total atherosclerotic CVD events, defined as recognized or unrecognized myocardial infarction (MI), angina pectoris, coronary insufficiency, intermittent claudication, coronary heart disease death, or atherothrombotic stroke (n = 178); major atherosclerotic CVD, defined as recognized acute MI, coronary insufficiency, coronary heart disease death, or atherothrombotic stroke (n = 83); and recognized acute MI (n = 59). Results  Twenty percent of participants (n = 352) were homozygous for the ESR1 c.454-397C allele. After adjustment for covariates (age, sex, body mass index, hypertension, diabetes mellitus, total cholesterol, high-density lipoprotein cholesterol, and cigarette smoking), the CC genotype was significantly associated with major atherosclerotic CVD, with an odds ratio of 2.0 (95% confidence interval [CI], 1.3-3.2; P = .004) compared with individuals with the CT or TT genotypes. Participants with the CC genotype had 3.0-fold greater odds of MI (95% CI, 1.7-5.2; P<.001) compared with those with the CT or TT genotype. The results remained significant when analyses were restricted to men; too few women had events to study them separately. Conclusions  Individuals with the common ESR1 c.454-397CC genotype have a substantial increase in risk of MI. Whether ESR1 c.454-397T>C is causally related to MI risk or in linkage disequilibrium with 1 or more causal variants remains to be determined. These findings support the importance of estrogen receptors in CVD susceptibility, especially in men. Estrogen receptor variation also has potential to explain recent conflicting data regarding the effects of hormone therapy on CVD susceptibility in women.