Cardiorespiratory fitness attenuates risk for major adverse cardiac events in hyperlipidemic men and women independent of statin therapy: The Henry Ford ExercIse Testing Project

Fitness attenuates long-term cardiovascular outcomes in women with ischemic heart disease and metabolic syndrome

Background

The prevalence of metabolic syndrome continues to increase steadily while fitness remains relatively low. The contribution of fitness on longer-term cardiovascular outcomes and mortality in individuals with cardiovascular disease and metabolic syndrome remains unknown.

Design

Women's Ischemia Syndrome Evaluation (WISE) prospective cohort (enrolled 1996-2001) of women undergoing invasive coronary angiography with signs/symptoms of ischemic heart disease.

Methods

Investigated the association of fitness, defined as >7METs measured by self-reported Duke Activity Status Index (DASI), and both metabolic syndrome (ATPIII criteria) and dysmetabolism (ATPIII criteria and/or treated diabetes) with long-term cardiovascular outcomes and all-cause mortality risk.

Results

Among the 492 women followed for a median of 8.6 years (range 0-11 years), 19.5% were fit-metabolically healthy (reference), 14.4% fit-metabolic syndrome, 29.9% unfit-metabolically healthy, and 36.2% unfit-metabolic syndrome. Compared to reference, MACE risk was 1.52-fold higher in fit-metabolic syndrome women (HR 1.52, 95% CI 1.03-2.26) and 2.42-fold higher in unfit-metabolic syndrome women (HR 2.42, 95% CI 1.30-4.48). Compared to reference, mortality risk was 1.96-fold higher in fit-dysmetabolism (HR 1.96, 95% CI 1.29-3.00) and 3-fold higher in unfit-dysmetabolism women (HR 3.0, 95% CI 1.66-5.43).

Conclusions

In a high risk cohort of women with signs/symptoms of ischemic heart disease, unfit-metabolically healthy and fit-metabolically unhealthy women were at higher risk of long-term MACE and mortality compared to fit-metabolically healthy women; and women who were unfit and metabolically unhealthy were at the highest risk. Our study demonstrates that metabolic health and fitness play an important role in long term outcomes that warrants further investigation.

Registration

https://www.clinicaltrials.gov/ct2/show/NCT00000554 (NCT00000554).

Prognostic Interplay Between Coronary Artery Calcium Scoring and Cardiorespiratory FItness: The CAC-FIT Study

OBJECTIVE

To assess the incremental prognostic role of coronary artery calcium score (CACS) and exercise capacity (EC), two independent prognostic tests in the assessment of patients with coronary artery disease.

METHODS

The cohort consisted of patients who had clinically indicated exercise stress testing and CACS assessment from January 1, 2015, to September 30, 2021, with a median of 27 days between each other. Exercise capacity was defined by peak metabolic equivalents of task (METs) achieved during exercise stress test. The CACS was determined by the Agatston method. Patients were observed from the latest test date to incident major adverse cardiac events (inclusive of all-cause death, nonfatal myocardial infarction, late revascularization, and admission for heart failure).

RESULTS

There were a` total of 1932 patients in the study population (mean age, 56±12 years; 42% female, 48% hypertension, 21% diabetes, 48% dyslipidemia). Peak METs below 6 was achieved in 8% of patients, and the median (interquartile range) CACS was 9 (0-203). In multivariable Cox regression models, both CACS (1 unit increase in log CACS: hazard ratio, 1.19; 95% CI, 1.06 to 1.34; P=.003;) and EC (1 unit increase in peak METs: hazard ratio, 0.89; 95% CI, 0.81 to 0.97; P=.01) were independently associated with outcomes. Using CACS+EC added incremental prognostic value over clinical and fitness models (C index increase from 0.68 to 0.75; P=.015). Incident event rates increased across categories of CACS and EC.

CONCLUSION

Our analysis found that CACS and EC have complementary risk-stratifying roles in coronary artery disease.

Fitness and prostate cancer screening, incidence, and mortality: Results from the Henry Ford Exercise Testing (FIT) Project

BACKGROUND

The relation between cardiorespiratory fitness (CRF) and prostate cancer is not well established. The objective of this study was to determine whether CRF is associated with prostate cancer screening, incidence, or mortality.

METHODS

The Henry Ford Exercise Testing Project is a retrospective cohort study of men aged 40 to 70 years without cancer who underwent physician-referred exercise stress testing from 1995 to 2009. CRF was quantified in metabolic equivalents of task (METs) (<6 [reference], 6-9, 10-11, and ≥12 METs), estimated from the peak workload achieved during a symptom-limited, maximal exercise stress test. Prostate-specific antigen (PSA) testing, incident prostate cancer, and all-cause mortality were analyzed with multivariable adjusted Poisson regression and Cox proportional hazard models.

RESULTS

In total, 22,827 men were included, of whom 739 developed prostate cancer, with a median follow-up of 7.5 years. Men who had high fitness (≥12 METs) had an 28% higher risk of PSA screening (95% CI, 1.2-1.3) compared with those who had low fitness (<6 METs. After adjusting for PSA screening, fitness was associated with higher prostate cancer incidence (men aged <55 years, P = .02; men aged >55 years, P ≤ .01), but not with advanced prostate cancer. Among the men who were diagnosed with prostate cancer, high fitness was associated with a 60% lower risk of all-cause mortality (95% CI, 0.2-0.9).

CONCLUSIONS

Although men with high fitness are more likely to undergo PSA screening, this does not fully account for the increased incidence of prostate cancer seen among these individuals. However, men with high fitness have a lower risk of death after a prostate cancer diagnosis, suggesting that the cancers identified may be low-risk with little impact on long-term outcomes.

The Interplay of the Global Atherosclerotic Cardiovascular Disease Risk Scoring and Cardiorespiratory Fitness for the Prediction of All-Cause Mortality and Myocardial Infarction: The Henry Ford ExercIse Testing Project (The FIT Project)

Cardiorespiratory fitness (CRF) is inversely associated with atherosclerotic cardiovascular disease (ASCVD) risk. It is unclear whether the prognostic value of CRF differs by baseline estimated ASCVD risk. We studied a retrospective cohort of patients without known heart failure or myocardial infarction (MI) who underwent treadmill stress testing. CRF was measured by metabolic equivalents of task (METs) and ASCVD risk was calculated using the Pooled Cohorts Equations. Multivariable-adjusted Cox regressions analyses examined the association between METs and incident all-cause mortality and MI outcomes stratified by baseline ASCVD risk. The C-index evaluated risk discrimination while net reclassification improvement evaluated reclassification with CRF added to the ASCVD risk score. Our study population consisted of 57,999 patients of mean age 53 (13) years, 49% women, 64% white, 29% black. Over a median follow-up 11 years (interquartile range 8 to 14 years) there were 6,670 (11%) deaths, while there were 1,757 (3.0%) MIs over a median follow-up of 6 years (interquartile range 3 to 8 years). Among patients with ASCVD risk ≥20%, those with METs ≥12 had a 77% lower risk of all-cause mortality (Hazard ratio 0.23 95% confidence interval = 0.20, 0.27) and 67% lower risk of MI (Hazard ratio 0.33 95% confidence interval = 0.24, 0.46) compared to METs <6. Similar results were obtained for those with ASCVD risk <5%. Addition of METs to ASCVD risk score improved the C-statistic from 0.778 to 0.798 for all-cause mortality and 0.726 to 0.733 for MI (both p <0.001). Addition of METs to ASCVD risk score significantly reclassified risk of all-cause mortality (p <0.001) but not MI (p = 0.052). In conclusion, CRF is inversely associated with risk of all-cause mortality and MI at all levels of ASCVD risk, and provides incremental risk discrimination and reclassification beyond the ASCVD risk score.

Cardiorespiratory Fitness, Coronary Artery Calcium, and Cardiovascular Disease Events in a Cohort of Generally Healthy Middle-Age Men: Results From the Cooper Center Longitudinal Study

BACKGROUND

A robust literature demonstrates that coronary artery calcification (CAC) and cardiorespiratory fitness (CRF) are independent predictors of cardiovascular disease (CVD) events. Much less is known about the joint associations of CRF and CAC with CVD risk. In the setting of high CAC, high versus low CRF has been associated with decreased CVD events. The goal of this study was to assess the effect of continuous levels of CRF on CVD risk in the setting of increasing CAC burden.

METHODS

We studied 8425 men without clinical CVD who underwent preventive medicine examinations that included an objective measurement of CRF and CAC between 1998 and 2007. There were 383 CVD events during an average follow-up of 8.4 years. Parametric proportional hazards regression models based on a Gompertz mortality rule were used to estimate total CVD incidence rates at 70 years of age as well as hazard ratios for the included covariates.

RESULTS

CVD events increased with increasing CAC and decreased with increasing CRF. Adjusting for CAC level (scores of 0, 1-99, 100-399, and ≥400), for each additional MET of fitness, there was an 11% lower risk for CVD events (hazard ratio, 0.89; 95% confidence interval, 0.84-0.94). When CAC and CRF were considered together, there was a strong association between continuous CRF and CVD incidence rates in all CAC groups.

CONCLUSIONS

In a large cohort of generally healthy men, there is an attenuation of CVD risk at all CAC levels with higher CRF.

Cardiorespiratory Fitness and Cardiovascular Disease Prevention: an Update

PURPOSE OF REVIEW

Cardiovascular diseases account for nearly one third of all deaths globally. Improving exercise capacity and cardiorespiratory fitness (CRF) has been an important target to reduce cardiovascular events. In addition, the American Heart Association defined decreased physical activity as the fourth risk factor for coronary artery disease. Multiple large cohort studies have evaluated the impact of CRF on outcomes. In this review, we will discuss the role of CRF in reducing cardiovascular morbidity and mortality.

RECENT FINDINGS

Recent data suggest that CRF has an important role in reducing not only cardiovascular and all-cause mortality, but also incident myocardial infarction, hypertension, diabetes, atrial fibrillation, heart failure, and stroke. Most recently, its role in cancer prevention started to emerge. CRF protective effects have also been seen in patients with prior comorbidities like prior coronary artery disease, heart failure, depression, end-stage renal disease, and stroke. The prognostic value of CRF has been demonstrated in various patient populations and cardiovascular conditions. Higher CRF is associated with improved survival and decreased incidence of cardiovascular diseases (CVD) and other comorbidities including hypertension, diabetes, heart failure, and atrial fibrillation.

Prognostic value of exercise capacity among men undergoing pharmacologic treatment for erectile dysfunction: The FIT Project

BACKGROUND

Vascular erectile dysfunction (ED) has been identified as a potentially useful risk factor for predicting future cardiovascular events, particularly in younger men. Because these men typically score more favorably on traditional cardiovascular disease risk assessment tools, there exists a gap in knowledge for how to most appropriately identify those men who would benefit from more aggressive treatments. To date, no studies have examined the impact of fitness on cardiovascular outcomes in men with ED. This study sought to examine the prognostic impact of maximal exercise capacity on cardiovascular-related outcomes in men ages 40 to 60 years being treated for ED.

HYPOTHESIS

We hypothesized that there would be an independent association between higher baseline fitness level and lower cardiovascular events.

METHODS

We analyzed 1152 men with pharmacy claims file-confirmed active pharmacologic treatment for ED from the Henry Ford Exercise Testing (FIT) Project (1991-2009). All patients were free of coronary heart disease and heart failure, and underwent clinician-referred exercise stress testing, with fitness measured in metabolic equivalents of task (METs). Multivariable Cox proportional hazard models adjusted for traditional cardiovascular risk factors were used to study the association between fitness and all-cause mortality, major adverse cardiovascular events (MACE) (defined as myocardial infarction or revascularization), and incident type 2 diabetes mellitus.

RESULTS

The mean age of the population was 53 years, with 39% African Americans. In multivariable analysis, each 1 MET of fitness was associated with a 16% lower risk of death (hazard ratio [HR]: 0.84, 95% confidence interval [CI]: 0.76-0.94, P = 0.002), and a nonsignificant reduction in MACE (HR: 0.89, 95% CI: 0.79-1.003, P = 0.048), and incident diabetes (HR: 0.92, 95% CI: 0.85-1.01, P = 0.129).

CONCLUSIONS

Higher baseline fitness is associated with improved cardiovascular prognosis in a population of middle-aged men treated for ED.

Effect of Beta-Blocker Therapy, Maximal Heart Rate, and Exercise Capacity During Stress Testing on Long-Term Survival (from The Henry Ford Exercise Testing Project)

Whether lower heart rate thresholds (defined as the percentage of age-predicted maximal heart rate achieved, or ppMHR) should be used to determine chronotropic incompetence in patients on beta-blocker therapy (BBT) remains unclear. In this retrospective cohort study, we analyzed 64,549 adults without congestive heart failure or atrial fibrillation (54 ± 13 years old, 46% women, 29% black) who underwent clinician-referred exercise stress testing at a single health care system in Detroit, Michigan from 1991 to 2009, with median follow-up of 10.6 years for all-cause mortality (interquartile range 7.7 to 14.7 years). Using Cox regression models, we assessed the effect of BBT, ppMHR, and estimated exercise capacity on mortality, with adjustment for demographic data, medical history, pertinent medications, and propensity to be on BBT. There were 9,259 deaths during follow-up. BBT was associated with an 8% lower adjusted achieved ppMHR (91% in no BBT vs 83% in BBT). ppMHR was inversely associated with all-cause mortality but with significant attenuation by BBT (per 10% ppMHR HR: no BBT: 0.80 [0.78 to 0.82] vs BBT: 0.89 [0.87 to 0.92]). Patients on BBT who achieved 65% ppMHR had a similar adjusted mortality rate as those not on BBT who achieved 85% ppMHR (p >0.05). Estimated exercise capacity further attenuated the prognostic value of ppMHR (per-10%-ppMHR HR: no BBT: 0.88 [0.86 to 0.90] vs BBT: 0.95 [0.93 to 0.98]). In conclusion, the prognostic value of ppMHR was significantly attenuated by BBT. For patients on BBT, a lower threshold of 65% ppMHR may be considered for determining worsened prognosis. Estimated exercise capacity further diminished the prognostic value of ppMHR particularly in patients on BBT.

Submaximal fitness and mortality risk reduction in coronary heart disease: a retrospective cohort study of community-based exercise rehabilitation

OBJECTIVES

To examine the association between submaximal cardiorespiratory fitness (sCRF) and all-cause mortality in a cardiac rehabilitation (CR) cohort.

DESIGN

Retrospective cohort study of participants entering CR between 26 May 1993 and 16 October 2006, followed up to 1 November 2013 (median 14 years, range 1.2-19.4 years).

SETTING

A community-based CR exercise programme in Leeds, West Yorkshire, UK.

PARTICIPANTS

A cohort of 534 men (76%) and 136 women with a clinical diagnosis of coronary heart disease (CHD), aged 22-82 years, attending CR were evaluated for the association between baseline sCRF and all-cause mortality. 416 participants with an exercise test following CR (median 14 weeks) were examined for changes in sCRF and all-cause mortality.

MAIN OUTCOME MEASURES

All-cause mortality and change in sCRF expressed in estimated metabolic equivalents (METs).

RESULTS

Baseline sCRF was a strong predictor of all-cause mortality; compared to the lowest sCRF group (<5 METs for women and <6 METs for men), mortality risk was 41% lower in those with moderate sCRF (HR 0.59; 95% CI 0.42 to 0.83) and 60% lower (HR 0.40; 95% CI 0.25 to 0.64) in those with higher sCRF levels (≥7 METs women and ≥8 METs for men). Although improvement in sCRF at 14 weeks was not associated with a significant mortality risk reduction (HR 0.91; 95% CI 0.79 to 1.06) for the whole cohort, in those with the lowest sCRF (and highest all-cause mortality) at baseline, each 1-MET improvement was associated with a 27% age-adjusted reduction in mortality risk (HR 0.73; 95% CI 0.57 to 0.94).

CONCLUSIONS

Higher baseline sCRF is associated with a reduced risk of all-cause mortality over 14 years in adults with CHD. Improving fitness through exercise-based CR is associated with significant risk reduction for the least fit.

High Exercise Capacity Attenuates the Risk of Early Mortality After a First Myocardial Infarction: The Henry Ford Exercise Testing (FIT) Project

OBJECTIVE

To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) after a first myocardial infarction (MI).

PATIENTS AND METHODS

This retrospective cohort study included 2061 patients without a history of MI (mean age, 62±12 years; 38% [n=790] women; 56% [n=1153] white) who underwent clinical treadmill stress testing in the Henry Ford Health System from January 1, 1991, through May 31, 2009, and suffered MI during follow-up (MI event proportion, 3.4%; mean time from the exercise test to MI, 6.1±4.3 years). Exercise capacity was categorized on the basis of peak metabolic equivalents (METs) achieved: less than 6, 6 to 9, 10 to 11, and 12 or more METs. Early mortality was defined as all-cause mortality within 28, 90, or 365 days of MI. Multivariable logistic regression models were used to assess the effect of EC on the risk of mortality at each time point post-MI adjusting for baseline demographic characteristics, cardiovascular risk factors, medication use, indication for stress testing, and year of MI.

RESULTS

The 28-day EM rate was 10.6% overall, and 13.9%, 10.7%, 6.9%, and 6.0% in the less than 6, 6 to 9, 10 to 11, and 12 or more METs categories, respectively (P<.001). Patients who died were more likely to be older, be less fit, be nonobese, have treated hypertension, and have a longer duration from baseline to incident MI (P<.05). Adjusted regression analyses revealed a decreased risk of EM with increasing EC categories. A 1-MET higher EC was associated with an 8% to 10% lower risk of mortality across all time points (28 days: odds ratio [OR], 0.92; 95% CI, 0.87-0.98; P=.006; 90 days: OR, 0.90; 95% CI, 0.86-0.95; P<.001; 365 days: OR, 0.91; 95% CI, 0.87-0.94; P<.001).

CONCLUSION

Higher baseline EC was independently associated with a lower risk of early death after a first MI.