Published online before print September 15, 2003, doi: 10.1161/01.CIR.0000091080.57509.E9
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(Circulation. 2003;108:1554.)
© 2003 American Heart Association, Inc.
Clinical Investigation and Reports |
Exercise Capacity and the Risk of Death in Women
The St James Women Take Heart Project
From the Department of Preventive Medicine (M.G., D.K.P., H.R.B.) and Department of Medicine (M.G.), Rush-Presbyterian-St Luke’s Medical Center, Chicago, Ill; Division of Cardiology (M.F.A.) and Department of Health Studies (D.S.L., R.A.T.), University of Chicago, Chicago, Ill; and Division of Cardiology (R.H.W., A.J.A-H.), St James Hospital, Chicago Heights, Ill.
Correspondence to Martha Gulati, MD, Rush Heart Institute, Rush-Presbyterian-St Luke’s Medical Center, 1725 West Harrison Ave, Suite 020, Chicago, IL 60612. E-mail Martha_Gulati{at}rush.edu
Received May 6, 2003; revision received July 15, 2003; accepted July 15, 2003.
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Abstract |
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Background— Cardiovascular disease is the leading cause of death among women and accounts for more than half of their deaths. Women have been underrepresented in most studies of cardiovascular disease. Reduced physical fitness has been shown to increase the risk of death in men. Exercise capacity measured by exercise stress test is an objective measure of physical fitness. The hypothesis that reduced exercise capacity is associated with an increased risk of death was investigated in a cohort of 5721 asymptomatic women who underwent baseline examinations in 1992.
Methods and Results— Information collected at baseline included medical and family history, demographic characteristics, physical examination, and symptom-limited stress ECG, using the Bruce protocol. Exercise capacity was measured in metabolic equivalents (MET). Nonfasting blood was analyzed at baseline. A National Death Index search was performed to identify all-cause death and date of death up to the end of 2000. The mean age of participants at baseline was 52±11 years. Framingham Risk Score–adjusted hazards ratios (with 95% CI) of death associated with MET levels of <5, 5 to 8, and >8 were 3.1 (2.0 to 4.7), 1.9 (1.3 to 2.9), and 1.00, respectively. The Framingham Risk Score–adjusted mortality risk decreased by 17% for every 1-MET increase.
Conclusions— This is the largest cohort of asymptomatic women studied in this context over the longest period of follow-up. This study confirms that exercise capacity is an independent predictor of death in asymptomatic women, greater than what has been previously established among men. The implications for clinical practice and health care policy are far reaching.
Key Words: exercise • epidemiology • mortality • women
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Introduction |
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Coronary artery disease (CAD) is the leading cause of death in both men and women in the United States. Women differ from men in their clinical presentation of CAD, their performance on diagnostic tests, and their prevalence of CAD. However, most of the available data on the noninvasive diagnosis of CAD are based on studies in men. Because the pretest likelihood of CAD, referral patterns and diagnostic ability of available tests probably differ for women, the clinical evaluation of women is difficult.1,2
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The standard exercise ECG is the most commonly used and the least costly noninvasive test to identify CAD. The value of the exercise ECG comes from the wealth of information that can be extracted from the test to provide important prognostic and diagnostic information.3 Epidemiologic studies have noted that exercise capacity is an independent predictor of cardiovascular events and all-cause death in men.4–11 Most studies examining the predictive value of exercise capacity have included almost exclusively male subjects4,5,7,8,10,11 or were retrospective studies.12 Also, most studies examining exercise capacity included only subjects with established CAD or cardiac symptoms.5,6,11–14 A prior study that included asymptomatic women showed an association between exercise capacity and death, but their extensive exclusion criteria limit the generalizability of their findings.15 Previous research has not evaluated all potential prognostic indicators from stress tests in asymptomatic women; therefore, the American College of Cardiology (ACC)/American Heart Association (AHA) Committee on Exercise Testing has identified this as an area in need of further study.3
In this study, we assess the prognostic value of exercise capacity in asymptomatic women. The aim of this paper is to determine whether exercise capacity is an independent predictor for all-cause death in asymptomatic women.
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Methods |
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This study was approved by St James Hospital and Rush-Presbyterian-St Luke’s Medical Center’s Institutional Review Board.
Participants
The St James Women Take Heart (WTH) Project comprises a volunteer cohort of women from the greater Chicago metropolitan area who responded to advertisements on television news and print media to participate in a study of heart disease in women during 1992. The target study enrollment was 5000. Inclusion criteria were age 35 years or older, a lack of symptomatic CAD, and the ability to walk on a treadmill at a moderate pace. Women were excluded if they had had typical anginal symptoms or myocardial infarction within the previous 3 months, had blood pressures of 
170/110 mm Hg before initiating the stress test, weighed >325 pounds (because of equipment limitations), or were pregnant; 5932 women met the inclusion criteria and were examined between May and July of 1992.
Our study-specific exclusion criteria excluded those who underwent a modified Bruce protocol stress test (n=109), because submaximal exercise testing does not accurately reflect physical fitness in the way that maximal exercise testing does.16 Women with self-reported CAD, previous percutaneous coronary angioplasty, coronary artery bypass graft, or congestive heart failure were also excluded from this analysis (n=91). We excluded 11 women because of incomplete data concerning cardiac risk factors.
After obtaining informed consent, participants provided data on demographics, lifestyle, behavioral variables, and medical history by self-administered questionnaire. Registered nurses performed physical examinations, which included height, weight, waist and hip measurements, blood pressure, radial pulse rate, and auscultation of the heart and lungs. Body mass index was calculated as weight in kilograms divided by height in meters squared. Blood pressure was measured by standard clinical procedures.17 Random urine and nonfasting blood samples were collected for laboratory analysis. Findings suggestive of congestive heart failure, valvular disease, or peripheral vascular disease were referred to the attending cardiologist. During the recording of the resting ECG, supine blood pressures were measured by cardiac technicians. Standing blood pressures were recorded before the stress test.
Framingham Risk Score
The Framingham Risk Score (FRS) has been described previously.18 The scoring for women is calculated by using a point system for total cholesterol, HDL, age, systolic blood pressure, diastolic blood pressure, the presence or absence of diabetes mellitus, and current smoking. The score ranges between -17 and +25, with higher scores indicating more cardiac risk factors.
We defined diabetes as either self-reported diabetes or nonfasting glucose level of 11 mmol/L.19
Exercise Testing
Participants underwent a symptom-limited treadmill test according to the Bruce protocol with exercise ECG measurements.20,21 Heart rate and blood pressure were measured, and a 12-lead ECG was recorded before exercise, at the end of each exercise stage, at peak exercise, and at 1-minute intervals during recovery. The test was discontinued for limiting symptoms (angina, dyspnea, and fatigue), abnormalities of rhythm or blood pressure, or marked and progressive ST-segment deviation. Target heart rates were not used as a predetermined end point.
Exercise capacity is expressed in units of metabolic equivalents (MET) and is an estimate of the maximal oxygen uptake for a given workload.22 A MET is a measure of ventilatory oxygen consumption expressed as multiples of basal resting requirements, where 1 MET is 1 unit of basal oxygen consumption, which equals 3.5 mL oxygen consumption per kilogram of body weight per minute for an average adult. The exercise capacity (in MET) is estimated by the speed and grade of the treadmill.23
Follow-Up
All-cause death was used as the end point. Deaths were identified by use of a National Death Index search, matching on date of birth and Social Security number and including all deaths through the year 2000.
Statistical Analyses
Descriptive analyses of all variables were examined. Population characteristics between those who met the primary end point (all-cause death) and the remaining participants were compared by using the 
2 test for categorical variables or the t test for continuous variables (2-sided). Exercise capacity (in MET) was modeled as a continuous variable and categorical variable. Exercise capacity was stratified as <5 MET, 5 to 8 MET, or >8 MET. This categorization was based on prior studies that showed decreased survival among those who achieved <5 MET and increased survival among those who are able achieve >8 MET when estimated either from exercise activities or a stress test.5,12,24
Person-time was calculated for each woman from date of test to date of death from any cause or December 31, 2000, whichever came first. Survival analysis was performed by means of Cox proportional-hazards regression models to determine the effect of exercise capacity on all-cause death, with exercise capacity analyzed as a continuous variable, adjusted for the FRS (as a continuous variable). Analysis of survival within the FRS tertiles for this cohort was performed with the use of the Cox proportional-hazards regression model. Survival was compared by categories of exercise capacity by means of Kaplan-Meier curves. The Cox proportional-hazards assumption was confirmed by visual inspection of the log(-log[survival]) curves. Statistical analyses were performed with the use of STATA 7.0.
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Results |
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Participant Characteristics
Study population characteristics are given in Table 1. A total of 5721 women met the inclusion criteria for this analysis. This was a predominantly white cohort (85.5%); 9.5% were black. The mean body mass index was 27.4±5.7 kg/m2. During the follow-up period, 3.2% (n=180) died. The mean (±SD) survival time was 8.4±0.67 years.
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The calculated FRS was normally distributed for this population, with a mean FRS of 6±6 U. The scores ranged from -12 to 20 U (Figure 1A). Comparing the surviving population with those who died, there was a statistically significant lower FRS in those alive than in those who died (mean FRS, 6±6 versus 9±5, P<0.0001) (Table 2). FRS tertiles strongly predicted survival in this cohort in Cox proportional-hazards regression (Figure 2A). The hazards ratios of death (with 95% CI) for the second and third tertiles compared with the first tertile (those with the lowest FRS) are 3.2 (1.9 to 5.4) and 6.7 (4.1 to 11.1), respectively (P
0.001). For each increasing tertile, the FRS predicts the 10-year CAD risk to be 3%, 4% to 8%, and 9%, respectively.18
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Exercise Test Results
The mean exercise capacity achieved was 8.0±2.7 MET. The distribution of the exercise capacity achieved in this cohort was normally distributed and ranged from 1.5 to 20.0 MET (Figure 1B). The mean exercise capacity achieved by those who died was significantly lower than that of the survivors (6.2±2.5 MET versus 8.0±2.7 MET, P<0.0001) (Table 2). Only 22% of those who died achieved the highest exercise capacity category (>8 MET) compared with 50% of those who survived (P<0.001); 6.1% of the cohort had significant ST-segment depression (1 mm), and the presence of ST-segment depression did not differ between those who survived and those who died (Table 2).
Predictors of Death
The FRS and exercise capacity achieved with stress testing are independent predictors of death, when included in the same model (Table 3). This analysis was not adjusted for age, because the FRS includes age and the correlation between age and the FRS was very high (r=0.74). There was no significant interaction between exercise capacity and the FRS (data not shown).
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For every increase in exercise capacity by 1 MET, the risk of death was reduced by 17% (P<0.001). Similarly, for every unit increase in the FRS, the risk of death increased by 9% (P<0.001). Because a lower exercise capacity may reflect subclinical disease, an analysis was performed in which women with early deaths (deaths before the 5th year) were excluded (not shown). The association between exercise capacity, the FRS, and death remained the same.
The survival curves for this cohort by exercise capacity categories, after adjusting for the FRS, are shown in Figure 2B. When compared with the >8 MET group, there were significant differences in the mortality rate among the categories, in which the hazards ratio of death (with 95% CI) was 1.9 (1.3 to 2.9) for the 5- to 8-MET group (P=0.002) and 3.1 (2.1 to 4.8) for the <5-MET group (P0.001). Adjustment for the FRS strengthened the association between exercise capacity and death (Figure 3).
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Discussion |
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We have shown that exercise capacity is a strong independent predictor of all-cause death in asymptomatic women, after adjusting for traditional cardiac risk factors. For each unit (1 MET) increase in exercise capacity, there was a 17% reduction in mortality rate.
Our data confirm the protective role of higher exercise capacity, even in the presence of established cardiac risk factors. Within this cohort of asymptomatic women, the risk of death doubled for those in the 5- to 8-MET exercise capacity category and tripled for those in the lowest (<5 MET) category when compared with the highest exercise capacity category and adjusted for the FRS.
The FRS18 and the Framingham Point Score (used in the Adult Treatment Panel III [ATP III] Report)19 are models used to predict the risk of cardiac disease in women. Both use a point system based on the presence or absence of cardiac risk factors to predict future cardiac events. These models, developed from the Framingham Heart Study25 and the Framingham Offspring Study,26 sum points for age, blood pressure, smoking status, total cholesterol (or LDL), and HDL. The difference between them is that the FRS incorporates diabetes into its score,18 whereas the ATP III guidelines state that the presence of diabetes is a cardiovascular disease equivalent.19 These prediction models are useful primary prevention devices that can estimate a person’s likelihood of future cardiac events, but neither model includes physical fitness (or lack thereof) as a cardiac risk factor within their model.
Our findings confirm that physical fitness, as measured by exercise capacity, is an independent risk factor for death in addition to other cardiac risk factors in asymptomatic women. Previous studies that have described this relation either did not include women4,5,7,10,27 or lacked the power to draw independent conclusions about women.6,12 Myers et al5 prospectively examined >6000 symptomatic men for a mean of 6.2 years. They found that for each 1-MET increase in exercise capacity, there was a 12% reduction in all-cause mortality rate. This study demonstrated the importance of physical fitness for symptomatic men, but our data show that exercise capacity is even more predictive in asymptomatic women.
Epidemiologic studies have noted that exercise capacity is an independent predictor of cardiovascular events and all-cause death in men.4–12,15 The Lipid Research Clinics Trial4 and the Aerobics Center Longitudinal Study7,10 were able to demonstrate the association between physical fitness and death in asymptomatic men. Exercise scores that have been found to predict future cardiac events and death have included the duration of exercise (as a marker of exercise capacity) in the score, including the widely used Duke Treadmill Score.24,28–30
The only study before the St James WTH Project that included asymptomatic women comes from the Cooper Clinic.15 Stress testing was performed on persons presenting for a preventive medical examination, including 3120 women. They found a trend of increased survival for women achieving higher exercise capacity levels, but only the lowest fitness quintile was significantly different from the highest four quintiles combined, after adjusting for cardiac risk factors. In contrast to our study, this study excluded those with diabetes, hypertension, an abnormal ECG (either at rest or with exercise), or inability to achieve 85% age-predicted heart rate. The restrictive exclusion criteria limit the generalizability of their findings. The St James WTH Project only excluded women who had a history of heart disease; target heart rate was not an end point of our stress testing. Our analysis confirms the trend seen in that study and is the first to demonstrate the association between exercise capacity and death in asymptomatic women.
There is significant evidence showing that decreased physical activity is associated with cardiac events and death in both men and women.25,27,31,32 Unlike physical fitness, which can be objectively measured, physical activity is a behavior, and how well it correlates with exercise capacity has not been extensively validated.16,33–36 Two studies that focused on women were based on the Framingham Heart Study32 and the Women’s Health Initiative (WHI) Observational Study.31 The Framingham Heart Study demonstrated a relation between physical activity and all-cause death. The WHI Observational Study was able to show an association between physical activity and cardiac events but concluded that women who engaged in both walking and vigorous activity for at least 2.5 hours per week carried a similar risk reduction of cardiac events when compared with less active women. In both studies, physical activity was assessed by a questionnaire and was essentially an estimate of activity status. Maximal exercise testing is an objective measure of physical fitness and is more readily quantifiable than assessment of physical activity.16,34
There are limitations to our study. The voluntary nature of the cohort and the method by which women were recruited affected the demographic makeup of the cohort. Although the participants do not represent a random sample of women from the greater Chicago metropolitan area, estimates of the direction and strength of associations between the physiological variables of interest in this study should be valid for similar, community-dwelling populations of adult women in the United States seen in primary care settings, the population of interest. Also, exercise capacity was measured by using the speed and grade of the treadmill rather than by directly measuring the oxygen consumption, which is more accurate.37 Finally, our regression analyses demonstrate an association between exercise capacity and all-cause death, not causation. Nonetheless, it is clear that exercise capacity is a marker for risk of death.
The implications of our findings for clinical practice and health care policy are far reaching. The AHA and other such organizations want to find a noninvasive screening test that can predict cardiac risk in asymptomatic individuals to target primary prevention efforts.38,39 Currently, the ACC/AHA and other experts do not recommend using the standard exercise test for screening in asymptomatic individuals.3,40 However, our study has demonstrated the added value of stress testing asymptomatic women to assess a woman’s risk of death, in addition to traditional cardiac risk factors. We have demonstrated a clear clinical rationale for routine stress testing in asymptomatic women. Furthermore, the achieved exercise capacity should be interpreted and translated to the patient to provide important prognostic information.
Although our study did not test the hypothesis that improved physical fitness through training might improve prognosis, it is interesting to speculate that it might. A prospective study of 9777 asymptomatic men given a stress test at baseline and 5 years after found that individuals who either maintained or improved their exercise capacity had significantly lower all-cause and cardiovascular mortality rates than the "persistently unfit" men. Importantly, this study demonstrated a 7.9% decrease in all-cause mortality rate in men for an increase in treadmill time of 
1 MET.10 In myocardial infarction survivors followed for 19 years, an increased exercise capacity of 1 MET was associated with an 8% to 14% reduction in mortality rate.41 High levels of physical fitness, as reflected by the exercise capacity achieved on a maximal stress test, have been shown to be protective of all-cause death in asymptomatic women.
Whether exercise capacity can be easily translated into a level of physical activity is still unknown and is an area in need of further research. Currently, the Surgeon General,42 the American College of Sports Medicine, the Centers for Disease Control and Prevention,43 and the AHA44 recommend that everyone should engage in a physically active lifestyle and that adults should perform moderately intense physical activity for at least 30 minutes per day, preferably every day. In the absence of specific data about the relation between physical activity and exercise capacity, continuing to encourage current physical activity recommendations seems appropriate.
The St James WTH Project confirms that exercise capacity is an independent predictor of death in asymptomatic women, even greater than that previously established among men.5,10 We were able to show a 17% reduction in mortality rate for every 1-MET increase in exercise capacity. Our findings strongly suggest that in addition to targeting traditional cardiac risk factors as part of the primary prevention evaluation, we must also evaluate the exercise capacity achieved on a maximal stress to fully assess a woman’s prognosis.
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Acknowledgments |
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This study was supported by grants from AstraZeneca, DuPont Pharmaceuticals, the Irwin Foundation, Merck, Pfizer/Pharmacia, Siemans-Gammasonics, and St James Hospital. We acknowledge Dr Arfan Al-Hani, who designed the St James WTH Project. Without his foresight, enthusiasm, and dedication, this study would not exist. His death is a loss to the investigators and participants of this study, as well as to the medical community at large. We are also indebted to the participants of the St James WTH Project, whose continued contribution to the study of heart disease in women is immeasurable.
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Footnotes |
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Arfan J. Al-Hani is deceased. 
Dr Black serves as a consultant to AstraZeneca, Blovail, Bristol-Myers Squibb, MSD, and Pfizer and is on the speakers’ bureaus of AstraZeneca, Bristol-Myers Squibb, MSD, Novartis, and Pfizer.
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 M. Gulati, R. M. Cooper-DeHoff, C. McClure, B. D. Johnson, L. J. Shaw, E. M. Handberg, I. Zineh, S. F. Kelsey, M. F. Arnsdorf, H. R. Black, et al. Adverse Cardiovascular Outcomes in Women With Nonobstructive Coronary Artery Disease: A Report From the Women's Ischemia Syndrome Evaluation Study and the St James Women Take Heart Project Arch Intern Med, May 11, 2009; 169(9): 843 - 850. [Abstract] [Full Text] [PDF]
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C. J. Lavie, R. J. Thomas, R. W. Squires, T. G. Allison, and R. V. Milani Exercise Training and Cardiac Rehabilitation in Primary and Secondary Prevention of Coronary Heart Disease Mayo Clin. Proc., April 1, 2009; 84(4): 373 - 383. [Abstract] [Full Text] [PDF]
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 R. Arena, J. Myers, J. Abella, S. Pinkstaff, P. Brubaker, B. Moore, D. Kitzman, M. A. Peberdy, D. Bensimhon, P. Chase, et al. Determining the Preferred Percent-Predicted Equation for Peak Oxygen Consumption in Patients With Heart Failure Circ Heart Fail, March 1, 2009; 2(2): 113 - 120. [Abstract] [Full Text] [PDF]
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 P. Kokkinos, A. Manolis, A. Pittaras, M. Doumas, A. Giannelou, D. B. Panagiotakos, C. Faselis, P. Narayan, S. Singh, and J. Myers Exercise Capacity and Mortality in Hypertensive Men With and Without Additional Risk Factors Hypertension, March 1, 2009; 53(3): 494 - 499. [Abstract] [Full Text] [PDF]
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C. K. Martin, T. S. Church, A. M. Thompson, C. P. Earnest, and S. N. Blair Exercise Dose and Quality of Life: A Randomized Controlled Trial Arch Intern Med, February 9, 2009; 169(3): 269 - 278. [Abstract] [Full Text] [PDF]
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R. Arena, J. Myers, and M. Guazzi The Clinical Significance of Aerobic Exercise Testing and Prescription: From Apparently Healthy to Confirmed Cardiovascular Disease American Journal of Lifestyle Medicine, November 1, 2008; 2(6): 519 - 536. [Abstract] [PDF]
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 K. S. Courneya, L. W. Jones, C. J. Peddle, C. M. Sellar, T. Reiman, A. A. Joy, N. Chua, L. Tkachuk, and J. R. Mackey Effects of Aerobic Exercise Training in Anemic Cancer Patients Receiving Darbepoetin Alfa: A Randomized Controlled Trial Oncologist, September 1, 2008; 13(9): 1012 - 1020. [Abstract] [Full Text] [PDF]
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 J. Tompkins, P. R Bosch, R. Chenowith, J. L Tiede, and J. M Swain Changes in Functional Walking Distance and Health-Related Quality of Life After Gastric Bypass Surgery Physical Therapy, August 1, 2008; 88(8): 928 - 935. [Abstract] [Full Text] [PDF]
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 M. S. LAUER and T. D. MILLER The exercise treadmill test: Estimating cardiovascular prognosis Cleveland Clinic Journal of Medicine, June 1, 2008; 75(6): 424 - 430. [Abstract] [Full Text] [PDF]
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P. Kokkinos, J. Myers, J. P. Kokkinos, A. Pittaras, P. Narayan, A. Manolis, P. Karasik, M. Greenberg, V. Papademetriou, and S. Singh Exercise Capacity and Mortality in Black and White Men Circulation, February 5, 2008; 117(5): 614 - 622. [Abstract] [Full Text] [PDF]
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P. N. Peterson, D. J. Magid, C. Ross, P. M. Ho, J. S. Rumsfeld, M. S. Lauer, E. E. Lyons, S. S. Smith, and F. A. Masoudi Association of Exercise Capacity on Treadmill With Future Cardiac Events in Patients Referred for Exercise Testing Arch Intern Med, January 28, 2008; 168(2): 174 - 179. [Abstract] [Full Text] [PDF]
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E. S.H. Kim, H. Ishwaran, E. Blackstone, and M. S. Lauer External Prognostic Validations and Comparisons of Age- and Gender-Adjusted Exercise Capacity Predictions J. Am. Coll. Cardiol., November 6, 2007; 50(19): 1867 - 1875. [Abstract] [Full Text] [PDF]
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L. W. Jones, M. J. Haykowsky, J. J. Swartz, P. S. Douglas, and J. R. Mackey Early Breast Cancer Therapy and Cardiovascular Injury J. Am. Coll. Cardiol., October 9, 2007; 50(15): 1435 - 1441. [Abstract] [Full Text] [PDF]
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 G. D. Harris and R. D. White Exercise Stress Testing in Patients With Type 2 Diabetes: When Are Asymptomatic Patients Screened? Clin. Diabetes, October 1, 2007; 25(4): 126 - 130. [Abstract] [Full Text] [PDF]
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L. W. Jones, M. Haykowsky, E. N. Pituskin, N. G. Jendzjowsky, C. R. Tomczak, R. G. Haennel, and J. R. Mackey Cardiovascular Reserve and Risk Profile of Postmenopausal Women After Chemoendocrine Therapy for Hormone Receptor Positive Operable Breast Cancer Oncologist, October 1, 2007; 12(10): 1156 - 1164. [Abstract] [Full Text] [PDF]
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R. Arena, J. Myers, M. A. Williams, M. Gulati, P. Kligfield, G. J. Balady, E. Collins, and G. Fletcher Assessment of Functional Capacity in Clinical and Research Settings: A Scientific Statement From the American Heart Association Committee on Exercise, Rehabilitation, and Prevention of the Council on Clinical Cardiology and the Council on Cardiovascular Nursing Circulation, July 17, 2007; 116(3): 329 - 343. [Full Text] [PDF]
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G. D. Harris A 52-Year-Old Woman With Hypertension and Diabetes Who Presents With Chest Pain Clin. Diabetes, July 1, 2007; 25(3): 115 - 118. [Full Text] [PDF]
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E. Ingelsson, M. G. Larson, R. S. Vasan, C. J. O'Donnell, X. Yin, J. N. Hirschhorn, C. Newton-Cheh, J. A. Drake, S. L. Musone, N. L. Heard-Costa, et al. Heritability, Linkage, and Genetic Associations of Exercise Treadmill Test Responses Circulation, June 12, 2007; 115(23): 2917 - 2924. [Abstract] [Full Text] [PDF]
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T. S. Church, C. P. Earnest, J. S. Skinner, and S. N. Blair Effects of Different Doses of Physical Activity on Cardiorespiratory Fitness Among Sedentary, Overweight or Obese Postmenopausal Women With Elevated Blood Pressure: A Randomized Controlled Trial JAMA, May 16, 2007; 297(19): 2081 - 2091. [Abstract] [Full Text] [PDF]
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 L. W. Jones, M. Haykowsky, C. J. Peddle, A. A. Joy, E. N. Pituskin, L. M. Tkachuk, K. S. Courneya, D. J. Slamon, and J. R. Mackey Cardiovascular Risk Profile of Patients with HER2/neu-Positive Breast Cancer Treated with Anthracycline-Taxane-Containing Adjuvant Chemotherapy and/or Trastuzumab Cancer Epidemiol. Biomarkers Prev., May 1, 2007; 16(5): 1026 - 1031. [Abstract] [Full Text] [PDF]
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 W. Shu, W. Lei, and S. Peng Recent development of ischaemic heart disease in sex difference Postgrad. Med. J., April 1, 2007; 83(978): 240 - 243. [Abstract] [Full Text] [PDF]
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P. Kligfield and M. S. Lauer Exercise Electrocardiogram Testing: Beyond the ST Segment Circulation, November 7, 2006; 114(19): 2070 - 2082. [Full Text] [PDF]
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 L A Gondoni, A Liuzzi, A M Titon, O Taronna, F Nibbio, P Ferrari, and G Leonetti A simple tool to predict exercise capacity of obese patients with ischaemic heart disease Heart, July 1, 2006; 92(7): 899 - 904. [Abstract] [Full Text] [PDF]
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M. H. Shishehbor, D. Litaker, C. E. Pothier, and M. S. Lauer Association of Socioeconomic Status With Functional Capacity, Heart Rate Recovery, and All-Cause Mortality JAMA, February 15, 2006; 295(7): 784 - 792. [Abstract] [Full Text] [PDF]
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L. J. Shaw, C. N. Bairey Merz, C. J. Pepine, S. E. Reis, V. Bittner, S. F. Kelsey, M. Olson, B. D. Johnson, S. Mankad, B. L. Sharaf, et al. Insights From the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study: Part I: Gender Differences in Traditional and Novel Risk Factors, Symptom Evaluation, and Gender-Optimized Diagnostic Strategies J. Am. Coll. Cardiol., February 7, 2006; 47(3_Suppl_S): S4 - S20. [Abstract] [Full Text] [PDF]
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L. J. Shaw, M. B. Olson, K. Kip, S. F. Kelsey, B. D. Johnson, D. B. Mark, S. E. Reis, S. Mankad, W. J. Rogers, G. M. Pohost, et al. The Value of Estimated Functional Capacity in Estimating Outcome: Results From the NHBLI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study J. Am. Coll. Cardiol., February 7, 2006; 47(3_Suppl_S): S36 - S43. [Abstract] [Full Text] [PDF]
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E. Handberg, B. D. Johnson, C. B. Arant, T. R. Wessel, R. A. Kerensky, G. von Mering, M. B. Olson, S. E. Reis, L. Shaw, C. N. Bairey Merz, et al. Impaired Coronary Vascular Reactivity and Functional Capacity in Women: Results From the NHLBI Women's Ischemia Syndrome Evaluation (WISE) Study J. Am. Coll. Cardiol., February 7, 2006; 47(3_Suppl_S): S44 - S49. [Abstract] [Full Text] [PDF]
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M. R. Carnethon, M. Gulati, and P. Greenland Prevalence and Cardiovascular Disease Correlates of Low Cardiorespiratory Fitness in Adolescents and Adults JAMA, December 21, 2005; 294(23): 2981 - 2988. [Abstract] [Full Text] [PDF]
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 K. F. Hossack, F. Haas, N. M. Byrne, M. Rey, M. J. Pletcher, C. McCulloch, M. Gulati, L. J. Shaw, and M. F. Arnsdorf Nomogram for exercise capacity in women. N. Engl. J. Med., November 24, 2005; 353(21): 2301 - 2303. [Full Text] [PDF]
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 M. Maeder, T. Wolber, R. Atefy, M. Gadza, P. Ammann, J. Myers, and H. Rickli Impact of the Exercise Mode on Exercise Capacity: Bicycle Testing Revisited Chest, October 1, 2005; 128(4): 2804 - 2811. [Abstract] [Full Text] [PDF]
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S. Mora, R. F. Redberg, A. R. Sharrett, and R. S. Blumenthal Enhanced Risk Assessment in Asymptomatic Individuals With Exercise Testing and Framingham Risk Scores Circulation, September 13, 2005; 112(11): 1566 - 1572. [Abstract] [Full Text] [PDF]
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M. Gulati, H. R. Black, L. J. Shaw, M. F. Arnsdorf, C. N. B. Merz, M. S. Lauer, T. H. Marwick, D. K. Pandey, R. H. Wicklund, and R. A. Thisted The Prognostic Value of a Nomogram for Exercise Capacity in Women N. Engl. J. Med., August 4, 2005; 353(5): 468 - 475. [Abstract] [Full Text] [PDF]
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M. Lauer, E. S. Froelicher, M. Williams, and P. Kligfield Exercise Testing in Asymptomatic Adults: A Statement for Professionals From the American Heart Association Council on Clinical Cardiology, Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention Circulation, August 2, 2005; 112(5): 771 - 776. [Abstract] [Full Text] [PDF]
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 O. J. Kemi, P. M. Haram, J. P. Loennechen, J.-B. Osnes, T. Skomedal, U. Wisloff, and O. Ellingsen Moderate vs. high exercise intensity: Differential effects on aerobic fitness, cardiomyocyte contractility, and endothelial function Cardiovasc Res, July 1, 2005; 67(1): 161 - 172. [Abstract] [Full Text] [PDF]
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J. H. Mieres, L. J. Shaw, A. Arai, M. J. Budoff, S. D. Flamm, W. G. Hundley, T. H. Marwick, L. Mosca, A. R. Patel, M. A. Quinones, et al. Role of Noninvasive Testing in the Clinical Evaluation of Women With Suspected Coronary Artery Disease: Consensus Statement From the Cardiac Imaging Committee, Council on Clinical Cardiology, and the Cardiovascular Imaging and Intervention Committee, Council on Cardiovascular Radiology and Intervention, American Heart Association Circulation, February 8, 2005; 111(5): 682 - 696. [Abstract] [Full Text] [PDF]
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 R. O. Bonow Update in Cardiology Ann Intern Med, October 19, 2004; 141(8): 628 - 634. [Full Text] [PDF]
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G. J. Balady, M. G. Larson, R. S. Vasan, E. P. Leip, C. J. O'Donnell, and D. Levy Usefulness of Exercise Testing in the Prediction of Coronary Disease Risk Among Asymptomatic Persons as a Function of the Framingham Risk Score Circulation, October 5, 2004; 110(14): 1920 - 1925. [Abstract] [Full Text] [PDF]
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M. K. Aktas, V. Ozduran, C. E. Pothier, R. Lang, and M. S. Lauer Global Risk Scores and Exercise Testing for Predicting All-Cause Mortality in a Preventive Medicine Program JAMA, September 22, 2004; 292(12): 1462 - 1468. [Abstract] [Full Text] [PDF]
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T. R. Wessel, C. B. Arant, M. B. Olson, B. D. Johnson, S. E. Reis, B. L. Sharaf, L. J. Shaw, E. Handberg, G. Sopko, S. F. Kelsey, et al. Relationship of Physical Fitness vs Body Mass Index With Coronary Artery Disease and Cardiovascular Events in Women JAMA, September 8, 2004; 292(10): 1179 - 1187. [Abstract] [Full Text] [PDF]
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 J. A. Laukkanen, S. Kurl, R. Salonen, R. Rauramaa, and J. T. Salonen The predictive value of cardiorespiratory fitness for cardiovascular events in men with various risk profiles: a prospective population-based cohort study Eur. Heart J., August 2, 2004; 25(16): 1428 - 1437. [Abstract] [Full Text] [PDF]
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B. T. Levy, A. J. Hartz, P. A. James, M. Gulati, D. K. Pandey, M. F. Arnsdorf, D. S. Lauderdale, R. A. Thisted, R. H. Wicklund, and H. R. Black Exercise Capacity and the Risk of Death in Women * Response Circulation, May 25, 2004; 109(20): e224 - e224. [Full Text] [PDF]
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A. Fowler-Brown, M. Pignone, M. Pletcher, J. A. Tice, S. F. Sutton, and K. N. Lohr Exercise Tolerance Testing To Screen for Coronary Heart Disease: A Systematic Review for the Technical Support for the U.S. Preventive Services Task Force Ann Intern Med, April 6, 2004; 140(7): W-9 - W-24. [Abstract] [Full Text] [PDF]
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M. R. Carnethon, S. S. Gidding, R. Nehgme, S. Sidney, D. R. Jacobs Jr, and K. Liu Cardiorespiratory Fitness in Young Adulthood and the Development of Cardiovascular Disease Risk Factors JAMA, December 17, 2003; 290(23): 3092 - 3100. [Abstract] [Full Text] [PDF]
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 Exercise Testing Results Predict Mortality in Women Journal Watch Women's Health, December 9, 2003; 2003(1209): 4 - 4. [Full Text]
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D. B. Mark and M. S. Lauer Exercise Capacity: The Prognostic Variable That Doesn't Get Enough Respect Circulation, September 30, 2003; 108(13): 1534 - 1536. [Full Text] [PDF]
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A. Fowler-Brown, M. Pignone, M. Pletcher, J. A. Tice, S. F. Sutton, and K. N. Lohr Exercise Tolerance Testing To Screen for Coronary Heart Disease: A Systematic Review for the Technical Support for the U.S. Preventive Services Task Force Ann Intern Med, April 6, 2004; 140(7): W-9 - W-24. [Abstract] [Full Text] [PDF]
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