Clinton Brawner | Henry Ford Health System (original) (raw)
Papers by Clinton Brawner
Journal of the American College of Cardiology, 2016
Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with ... more Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with chronic heart failure (HF). However, few published studies have simultaneously compared the relative prognostic strength of multiple CPX variables. The study sought to describe the strength of the association among variables measured during a CPX test and all-cause mortality in patients with HF with reduced ejection fraction (HFrEF), including the influence of sex and patient effort, as measured by respiratory exchange ratio (RER). Among patients (n = 2,100, 29% women) enrolled in the HF-ACTION (HF-A Controlled Trial Investigating Outcomes of exercise traiNing) trial, 10 CPX test variables measured at baseline (e.g., peak oxygen uptake [Vo2], exercise duration, percent predicted peak Vo2 [%ppVo2], ventilatory efficiency) were examined. Over a median follow-up of 32 months, there were 357 deaths. All CPX variables, except RER, were related to all-cause mortality (all p < 0.0001). Both %ppVo2 and exercise duration were equally able to predict (Wald chi-square: ∼141) and discriminate (c-index: 0.69) mortality. Peak Vo2 (ml·kg(-1)·min(-1)) was the strongest predictor of mortality among men (Wald chi-square: 129) and exercise duration among women (Wald chi-square: 41). Multivariable analyses showed that %ppVo2, exercise duration, and peak Vo2 (ml·kg(-1)·min(-1)) were similarly able to predict and discriminate mortality. In men, a 10% 1-year mortality rate corresponded to a peak Vo2 of 10.9 ml·kg(-1)·min(-1) versus 5.3 ml·kg(-1)·min(-1) in women. Peak Vo2, exercise duration, and % ppVo2 carried the strongest ability to predict and discriminate the likelihood of death in patients with HFrEF. The prognosis associated with a given peak Vo2 differed by sex. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437).
Mayo Clinic Proceedings, 2016
To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) afte... more To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) after a first myocardial infarction (MI). 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. 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). Higher baseline EC was independently associated with a lower risk of early death after a first MI.
Medicine & Science in Sports & Exercise, 2006
Medicine & Science in Sports & Exercise, 2004
Circulation, Mar 10, 2015
JACC. Heart failure, 2015
The American Journal of Cardiology, 2015
Decreases in systolic blood pressure during exercise may predispose to arrhythmias such as atrial... more Decreases in systolic blood pressure during exercise may predispose to arrhythmias such as atrial fibrillation (AF) because of underlying abnormal autonomic tone. We examined the association between systolic blood pressure response and incident AF in 57,442 (mean age 54 ± 13 years, 47% women, and 29% black) patients free of baseline AF who underwent exercise treadmill stress testing from the Henry Ford ExercIse Testing project. Exercise systolic blood pressure response was examined as a categorical variable across clinically relevant categories (>20 mm Hg: referent; 1 to 20 mm Hg, and ≤0 mm Hg) and per 1-SD decrease. Cox regression, adjusting for demographics, cardiovascular risk factors, medications, history of coronary heart disease, history of heart failure, and metabolic equivalent of task achieved, was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between systolic blood pressure response and incident AF. Over a median follow-up of 5.0 years, a total of 3,381 cases (5.9%) of AF were identified. An increased risk of AF was observed with decreasing systolic blood pressure response (>20 mm Hg: HR 1.0, referent; 1 to 20 mm Hg: HR 1.09, 95% CI 0.99, 1.20; ≤0 mm Hg: HR 1.22, 95% CI 1.06 to 1.40). Similar results were obtained per 1-SD decrease in systolic blood pressure response (HR 1.08, 95% CI 1.04 to 1.12). The results were consistent when stratified by age, sex, race, hypertension, and coronary heart disease. In conclusion, our results suggest that a decreased systolic blood pressure response during exercise may identify subjects who are at risk for developing AF.
American journal of hypertension, Jan 25, 2015
Given that sympathetic tone is associated with hypertension, we sought to determine whether resti... more Given that sympathetic tone is associated with hypertension, we sought to determine whether resting heart rate (RHR), as a surrogate for cardiac autonomic function, was associated with incident hypertension. We analyzed 21,873 individuals without a history of hypertension who underwent a clinically indicated exercise stress test. Baseline RHR was assessed prior to testing and was categorized as <70, 70-85, and >85 beats-per-minute (bpm). Incident hypertension was defined by subsequent diagnosis codes for new-onset hypertension from three or more encounters. We tested for effect modification by age (<60 vs. ≥60 years), sex, race, and history of coronary heart disease (CHD). Mean (±SD) age was 49 (±12) years, 55% were men and 21% were Black. Compared to the lowest RHR (<70 bpm) category, patients in the highest category (>85 bpm) were younger, more likely to be female, heavier, diabetic, and achieve lower metabolic equivalents (METS). Over a median of 4 years follow-up,...
International Journal of Cardiology, 2015
Journal of the American Heart Association, 2015
The prognostic significance of modest elevations in exercise systolic blood pressure response has... more The prognostic significance of modest elevations in exercise systolic blood pressure response has not been extensively examined. We examined the association between systolic blood pressure response and all-cause death and incident myocardial infarction (MI) in 44 089 (mean age 53±13 years, 45% female, 26% black) patients who underwent exercise treadmill stress testing from the Henry Ford ExercIse Testing (FIT) Project (1991-2010). Exercise systolic blood pressure response was examined as a categorical variable (>20 mm Hg: referent; 1 to 20 mm Hg, and ≤0 mm Hg) and per 1 SD decrease. Cox regression was used to compute hazard ratios (HR) and 95% CI for the association between systolic blood pressure response and all-cause death and incident MI. Over a median follow-up of 10 years, a total of 4782 (11%) deaths occurred and over 5.2 years, a total of 1188 (2.7%) MIs occurred. In a Cox regression analysis adjusted for demographics, physical fitness, and cardiovascular risk factors, an...
American Heart Journal, 2015
We sought to evaluate the effect of cardiorespiratory fitness (CRF) in predicting mortality, myoc... more We sought to evaluate the effect of cardiorespiratory fitness (CRF) in predicting mortality, myocardial infarction (MI), and revascularization in patients with hyperlipidemia after stratification by gender and statin therapy. This retrospective cohort study included 33,204 patients with hyperlipidemia (57 ± 12 years old, 56% men, 25% black) who underwent physician-referred treadmill stress testing at the Henry Ford Health System from 1991 to 2009. Patients were stratified by gender, baseline statin therapy, and estimated metabolic equivalents from stress testing. We computed hazard ratios using Cox regression models after adjusting for demographics, cardiac risk factors, comorbidities, pertinent medications, interaction terms, and indication for stress testing. There were 4,851 deaths, 1,962 MIs, and 2,686 revascularizations over a median follow-up of 10.3 years. In men and women not on statin therapy and men and women on statin therapy, each 1-metabolic equivalent increment in CRF was associated with hazard ratios of 0.86 (95% CI 0.85-0.88), 0.83 (95% CI 0.81-0.85), 0.85 (95% CI 0.83-0.87), and 0.84 (95% CI 0.81-0.87) for mortality; 0.93 (95% CI 0.90-0.96), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.86-0.92), and 0.90 (95% CI 0.86-0.95) for MI; and 0.91 (95% CI 0.88-0.93), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.87-0.92), and 0.90 (95% CI 0.86-0.94) for revascularization, respectively. No significant interactions were observed between CRF and statin therapy (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; .23). Higher CRF attenuated risk for mortality, MI, and revascularization independent of gender and statin therapy in patients with hyperlipidemia. These results reinforce the prognostic value of CRF and support greater promotion of CRF in this patient population.
Circulation, Jan 22, 2015
hn hns Ho opk pk pkins C Ciccarone Center for the Preven nt t tio o on of Heart Di i ise s s ase,... more hn hns Ho opk pk pkins C Ciccarone Center for the Preven nt t tio o on of Heart Di i ise s s ase, B Baltimore, MD; 5 Wayne S S Sta a ate University ty y, De Detr tr roi i oit t t, M M MI; I; I; 6 6 6 Ki i ing ng ng A A Ab bdul-A -A -Aziz Ca a ard d dia ia iac c C Ce Cen n nter r r, N N Nati ti io o ona al G G Gu u uard d H H He e ealt lt lth h h A Af Affa fa fair r rs,
Journal of the American College of Cardiology, 2015
Previous studies have shown that black patients have lower age-and sex-adjusted risk of incident ... more Previous studies have shown that black patients have lower age-and sex-adjusted risk of incident atrial fibrillation (AF) compared to whites. We examined whether these differences could be partially explained by cardiorespiratory fitness (CRF).
Journal of the American College of Cardiology, 2015
Diabetes care, Jan 12, 2015
Prior evidence has linked higher cardiorespiratory fitness with a lower risk of diabetes in ambul... more Prior evidence has linked higher cardiorespiratory fitness with a lower risk of diabetes in ambulatory populations. Using a demographically diverse study sample, we examined the association of fitness with incident diabetes in 46,979 patients from The Henry Ford ExercIse Testing (FIT) Project without diabetes at baseline. Fitness was measured during a clinician-referred treadmill stress test performed between 1991 and 2009. Incident diabetes was defined as a new diagnosis of diabetes on three separate consecutive encounters derived from electronic medical records or administrative claims files. Analyses were performed with Cox proportional hazards models and were adjusted for diabetes risk factors. The mean age was 53 years with 48% women and 27% black patients. Mean metabolic equivalents (METs) achieved was 9.5 (SD 3.0). During a median follow-up period of 5.2 years (interquartile range 2.6-8.3 years), there were 6,851 new diabetes cases (14.6%). After adjustment, patients achievin...
Mayo Clinic proceedings, 2015
To determine which routinely collected exercise test variables most strongly correlate with survi... more To determine which routinely collected exercise test variables most strongly correlate with survival and to derive a fitness risk score that can be used to predict 10-year survival. This was a retrospective cohort study of 58,020 adults aged 18 to 96 years who were free of established heart disease and were referred for an exercise stress test from January 1, 1991, through May 31, 2009. Demographic, clinical, exercise, and mortality data were collected on all patients as part of the Henry Ford ExercIse Testing (FIT) Project. Cox proportional hazards models were used to identify exercise test variables most predictive of survival. A "FIT Treadmill Score" was then derived from the β coefficients of the model with the highest survival discrimination. The median age of the 58,020 participants was 53 years (interquartile range, 45-62 years), and 28,201 (49%) were female. Over a median of 10 years (interquartile range, 8-14 years), 6456 patients (11%) died. After age and sex, pe...
Medicine and Science in Sports and Exercise, 2007
International Journal of Cardiology, 2015
To describe the effect of the duration of the data averaging interval on the calculated peak oxyg... more To describe the effect of the duration of the data averaging interval on the calculated peak oxygen uptake (VO 2 ) reported from a symptom-limited maximal exercise test in patients with heart failure. Methods: Maximal exercise test results from 275 patients diagnosed with stable heart failure due to left ventricular systolic dysfunction (ejection fraction b 45%; age: 45-75 years; peak VO 2 : 8.0-20.0 mL/kg/min), were examined. Sampling rates of 10, 20, 30 and 60 s were used to calculate peak VO 2 , which was identified as the highest interval value that occurred during the final minute of exercise or the first interval in immediate recovery. Results: Mean peak VO 2 (mL/kg/min) across the four sampling periods was as follows: 14.0 ± 3.0 (10 s), 13.7 ± 3.0 (20 s), 13.5 ± 3.0 (30 s) and 13.2 ± 2.9 (60 s) and there was a significant reduction with increasing averaging duration (p b 0.0001). Peak VO 2 was significantly different between the 10 s and 60 s sampling times (p b 0.0001). Peak respiratory exchange ratio (RER) was also significantly different between 10 and 60 s sampling rates (p b 0.0001). Sub-analyses showed peak VO 2 values in those people achieving RER N 1.05 to be + 0.8 ± 0.7 mL/kg/min higher than those who had not achieved RER values N 1.05; similar findings, + 0.8 ± 0.7 mL/kg/min, were seen in those patients achieving RER N 1.10 versus those who did not. Conclusions: Sampling rate method has a significant effect on calculated peak VO 2 and RER. We suggest that laboratories standardize their sampling rate method to ensure consistency.
Historically, patients with heart failure were advised to avoid exertion due to fear that the add... more Historically, patients with heart failure were advised to avoid exertion due to fear that the added myocardial stress would worsen heart function. However, between 1979 and 1991,~ve uncontrolled trials demonstrated that moderate exercise training can partially reverse the exercise intolerance common among patients with heart failure. Since 1991, numerous randomized exercise trials demonstrated a 12% to 33% improvement in exercise capacity, as measured by oxygen consumption. The mechanisms by which this improvement occurs are now being studied. Potential mechanisms include improved cardiac output due to increases in both peak stroke volume and reversal of chronotropic incompetence; improved regional blood _ow to the metabolically more active skeletal muscle; and partial reversal of skeletal muscle histochemical abnormalities such as increased oxidative enzymes and a "re-shift" iñ ber type toward increased type I~bers. Improved sympathetic function has also been noted with exercise training, evidenced by decreased norepinephrine spillover and increased heart rate variability. Exercise training can be of bene~t in selected patients with stable New York Heart Association class II or III heart failure.
Cardiac Rehabilitation, 2007
Journal of the American College of Cardiology, 2016
Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with ... more Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with chronic heart failure (HF). However, few published studies have simultaneously compared the relative prognostic strength of multiple CPX variables. The study sought to describe the strength of the association among variables measured during a CPX test and all-cause mortality in patients with HF with reduced ejection fraction (HFrEF), including the influence of sex and patient effort, as measured by respiratory exchange ratio (RER). Among patients (n = 2,100, 29% women) enrolled in the HF-ACTION (HF-A Controlled Trial Investigating Outcomes of exercise traiNing) trial, 10 CPX test variables measured at baseline (e.g., peak oxygen uptake [Vo2], exercise duration, percent predicted peak Vo2 [%ppVo2], ventilatory efficiency) were examined. Over a median follow-up of 32 months, there were 357 deaths. All CPX variables, except RER, were related to all-cause mortality (all p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001). Both %ppVo2 and exercise duration were equally able to predict (Wald chi-square: ∼141) and discriminate (c-index: 0.69) mortality. Peak Vo2 (ml·kg(-1)·min(-1)) was the strongest predictor of mortality among men (Wald chi-square: 129) and exercise duration among women (Wald chi-square: 41). Multivariable analyses showed that %ppVo2, exercise duration, and peak Vo2 (ml·kg(-1)·min(-1)) were similarly able to predict and discriminate mortality. In men, a 10% 1-year mortality rate corresponded to a peak Vo2 of 10.9 ml·kg(-1)·min(-1) versus 5.3 ml·kg(-1)·min(-1) in women. Peak Vo2, exercise duration, and % ppVo2 carried the strongest ability to predict and discriminate the likelihood of death in patients with HFrEF. The prognosis associated with a given peak Vo2 differed by sex. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437).
Mayo Clinic Proceedings, 2016
To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) afte... more To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) after a first myocardial infarction (MI). 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. 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&amp;amp;amp;amp;amp;lt;.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&amp;amp;amp;amp;amp;lt;.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&amp;amp;amp;amp;amp;lt;.001; 365 days: OR, 0.91; 95% CI, 0.87-0.94; P&amp;amp;amp;amp;amp;lt;.001). Higher baseline EC was independently associated with a lower risk of early death after a first MI.
Medicine & Science in Sports & Exercise, 2006
Medicine & Science in Sports & Exercise, 2004
Circulation, Mar 10, 2015
JACC. Heart failure, 2015
The American Journal of Cardiology, 2015
Decreases in systolic blood pressure during exercise may predispose to arrhythmias such as atrial... more Decreases in systolic blood pressure during exercise may predispose to arrhythmias such as atrial fibrillation (AF) because of underlying abnormal autonomic tone. We examined the association between systolic blood pressure response and incident AF in 57,442 (mean age 54 ± 13 years, 47% women, and 29% black) patients free of baseline AF who underwent exercise treadmill stress testing from the Henry Ford ExercIse Testing project. Exercise systolic blood pressure response was examined as a categorical variable across clinically relevant categories (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;20 mm Hg: referent; 1 to 20 mm Hg, and ≤0 mm Hg) and per 1-SD decrease. Cox regression, adjusting for demographics, cardiovascular risk factors, medications, history of coronary heart disease, history of heart failure, and metabolic equivalent of task achieved, was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between systolic blood pressure response and incident AF. Over a median follow-up of 5.0 years, a total of 3,381 cases (5.9%) of AF were identified. An increased risk of AF was observed with decreasing systolic blood pressure response (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;20 mm Hg: HR 1.0, referent; 1 to 20 mm Hg: HR 1.09, 95% CI 0.99, 1.20; ≤0 mm Hg: HR 1.22, 95% CI 1.06 to 1.40). Similar results were obtained per 1-SD decrease in systolic blood pressure response (HR 1.08, 95% CI 1.04 to 1.12). The results were consistent when stratified by age, sex, race, hypertension, and coronary heart disease. In conclusion, our results suggest that a decreased systolic blood pressure response during exercise may identify subjects who are at risk for developing AF.
American journal of hypertension, Jan 25, 2015
Given that sympathetic tone is associated with hypertension, we sought to determine whether resti... more Given that sympathetic tone is associated with hypertension, we sought to determine whether resting heart rate (RHR), as a surrogate for cardiac autonomic function, was associated with incident hypertension. We analyzed 21,873 individuals without a history of hypertension who underwent a clinically indicated exercise stress test. Baseline RHR was assessed prior to testing and was categorized as <70, 70-85, and >85 beats-per-minute (bpm). Incident hypertension was defined by subsequent diagnosis codes for new-onset hypertension from three or more encounters. We tested for effect modification by age (<60 vs. ≥60 years), sex, race, and history of coronary heart disease (CHD). Mean (±SD) age was 49 (±12) years, 55% were men and 21% were Black. Compared to the lowest RHR (<70 bpm) category, patients in the highest category (>85 bpm) were younger, more likely to be female, heavier, diabetic, and achieve lower metabolic equivalents (METS). Over a median of 4 years follow-up,...
International Journal of Cardiology, 2015
Journal of the American Heart Association, 2015
The prognostic significance of modest elevations in exercise systolic blood pressure response has... more The prognostic significance of modest elevations in exercise systolic blood pressure response has not been extensively examined. We examined the association between systolic blood pressure response and all-cause death and incident myocardial infarction (MI) in 44 089 (mean age 53±13 years, 45% female, 26% black) patients who underwent exercise treadmill stress testing from the Henry Ford ExercIse Testing (FIT) Project (1991-2010). Exercise systolic blood pressure response was examined as a categorical variable (>20 mm Hg: referent; 1 to 20 mm Hg, and ≤0 mm Hg) and per 1 SD decrease. Cox regression was used to compute hazard ratios (HR) and 95% CI for the association between systolic blood pressure response and all-cause death and incident MI. Over a median follow-up of 10 years, a total of 4782 (11%) deaths occurred and over 5.2 years, a total of 1188 (2.7%) MIs occurred. In a Cox regression analysis adjusted for demographics, physical fitness, and cardiovascular risk factors, an...
American Heart Journal, 2015
We sought to evaluate the effect of cardiorespiratory fitness (CRF) in predicting mortality, myoc... more We sought to evaluate the effect of cardiorespiratory fitness (CRF) in predicting mortality, myocardial infarction (MI), and revascularization in patients with hyperlipidemia after stratification by gender and statin therapy. This retrospective cohort study included 33,204 patients with hyperlipidemia (57 ± 12 years old, 56% men, 25% black) who underwent physician-referred treadmill stress testing at the Henry Ford Health System from 1991 to 2009. Patients were stratified by gender, baseline statin therapy, and estimated metabolic equivalents from stress testing. We computed hazard ratios using Cox regression models after adjusting for demographics, cardiac risk factors, comorbidities, pertinent medications, interaction terms, and indication for stress testing. There were 4,851 deaths, 1,962 MIs, and 2,686 revascularizations over a median follow-up of 10.3 years. In men and women not on statin therapy and men and women on statin therapy, each 1-metabolic equivalent increment in CRF was associated with hazard ratios of 0.86 (95% CI 0.85-0.88), 0.83 (95% CI 0.81-0.85), 0.85 (95% CI 0.83-0.87), and 0.84 (95% CI 0.81-0.87) for mortality; 0.93 (95% CI 0.90-0.96), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.86-0.92), and 0.90 (95% CI 0.86-0.95) for MI; and 0.91 (95% CI 0.88-0.93), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.87-0.92), and 0.90 (95% CI 0.86-0.94) for revascularization, respectively. No significant interactions were observed between CRF and statin therapy (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; .23). Higher CRF attenuated risk for mortality, MI, and revascularization independent of gender and statin therapy in patients with hyperlipidemia. These results reinforce the prognostic value of CRF and support greater promotion of CRF in this patient population.
Circulation, Jan 22, 2015
hn hns Ho opk pk pkins C Ciccarone Center for the Preven nt t tio o on of Heart Di i ise s s ase,... more hn hns Ho opk pk pkins C Ciccarone Center for the Preven nt t tio o on of Heart Di i ise s s ase, B Baltimore, MD; 5 Wayne S S Sta a ate University ty y, De Detr tr roi i oit t t, M M MI; I; I; 6 6 6 Ki i ing ng ng A A Ab bdul-A -A -Aziz Ca a ard d dia ia iac c C Ce Cen n nter r r, N N Nati ti io o ona al G G Gu u uard d H H He e ealt lt lth h h A Af Affa fa fair r rs,
Journal of the American College of Cardiology, 2015
Previous studies have shown that black patients have lower age-and sex-adjusted risk of incident ... more Previous studies have shown that black patients have lower age-and sex-adjusted risk of incident atrial fibrillation (AF) compared to whites. We examined whether these differences could be partially explained by cardiorespiratory fitness (CRF).
Journal of the American College of Cardiology, 2015
Diabetes care, Jan 12, 2015
Prior evidence has linked higher cardiorespiratory fitness with a lower risk of diabetes in ambul... more Prior evidence has linked higher cardiorespiratory fitness with a lower risk of diabetes in ambulatory populations. Using a demographically diverse study sample, we examined the association of fitness with incident diabetes in 46,979 patients from The Henry Ford ExercIse Testing (FIT) Project without diabetes at baseline. Fitness was measured during a clinician-referred treadmill stress test performed between 1991 and 2009. Incident diabetes was defined as a new diagnosis of diabetes on three separate consecutive encounters derived from electronic medical records or administrative claims files. Analyses were performed with Cox proportional hazards models and were adjusted for diabetes risk factors. The mean age was 53 years with 48% women and 27% black patients. Mean metabolic equivalents (METs) achieved was 9.5 (SD 3.0). During a median follow-up period of 5.2 years (interquartile range 2.6-8.3 years), there were 6,851 new diabetes cases (14.6%). After adjustment, patients achievin...
Mayo Clinic proceedings, 2015
To determine which routinely collected exercise test variables most strongly correlate with survi... more To determine which routinely collected exercise test variables most strongly correlate with survival and to derive a fitness risk score that can be used to predict 10-year survival. This was a retrospective cohort study of 58,020 adults aged 18 to 96 years who were free of established heart disease and were referred for an exercise stress test from January 1, 1991, through May 31, 2009. Demographic, clinical, exercise, and mortality data were collected on all patients as part of the Henry Ford ExercIse Testing (FIT) Project. Cox proportional hazards models were used to identify exercise test variables most predictive of survival. A "FIT Treadmill Score" was then derived from the β coefficients of the model with the highest survival discrimination. The median age of the 58,020 participants was 53 years (interquartile range, 45-62 years), and 28,201 (49%) were female. Over a median of 10 years (interquartile range, 8-14 years), 6456 patients (11%) died. After age and sex, pe...
Medicine and Science in Sports and Exercise, 2007
International Journal of Cardiology, 2015
To describe the effect of the duration of the data averaging interval on the calculated peak oxyg... more To describe the effect of the duration of the data averaging interval on the calculated peak oxygen uptake (VO 2 ) reported from a symptom-limited maximal exercise test in patients with heart failure. Methods: Maximal exercise test results from 275 patients diagnosed with stable heart failure due to left ventricular systolic dysfunction (ejection fraction b 45%; age: 45-75 years; peak VO 2 : 8.0-20.0 mL/kg/min), were examined. Sampling rates of 10, 20, 30 and 60 s were used to calculate peak VO 2 , which was identified as the highest interval value that occurred during the final minute of exercise or the first interval in immediate recovery. Results: Mean peak VO 2 (mL/kg/min) across the four sampling periods was as follows: 14.0 ± 3.0 (10 s), 13.7 ± 3.0 (20 s), 13.5 ± 3.0 (30 s) and 13.2 ± 2.9 (60 s) and there was a significant reduction with increasing averaging duration (p b 0.0001). Peak VO 2 was significantly different between the 10 s and 60 s sampling times (p b 0.0001). Peak respiratory exchange ratio (RER) was also significantly different between 10 and 60 s sampling rates (p b 0.0001). Sub-analyses showed peak VO 2 values in those people achieving RER N 1.05 to be + 0.8 ± 0.7 mL/kg/min higher than those who had not achieved RER values N 1.05; similar findings, + 0.8 ± 0.7 mL/kg/min, were seen in those patients achieving RER N 1.10 versus those who did not. Conclusions: Sampling rate method has a significant effect on calculated peak VO 2 and RER. We suggest that laboratories standardize their sampling rate method to ensure consistency.
Historically, patients with heart failure were advised to avoid exertion due to fear that the add... more Historically, patients with heart failure were advised to avoid exertion due to fear that the added myocardial stress would worsen heart function. However, between 1979 and 1991,~ve uncontrolled trials demonstrated that moderate exercise training can partially reverse the exercise intolerance common among patients with heart failure. Since 1991, numerous randomized exercise trials demonstrated a 12% to 33% improvement in exercise capacity, as measured by oxygen consumption. The mechanisms by which this improvement occurs are now being studied. Potential mechanisms include improved cardiac output due to increases in both peak stroke volume and reversal of chronotropic incompetence; improved regional blood _ow to the metabolically more active skeletal muscle; and partial reversal of skeletal muscle histochemical abnormalities such as increased oxidative enzymes and a "re-shift" iñ ber type toward increased type I~bers. Improved sympathetic function has also been noted with exercise training, evidenced by decreased norepinephrine spillover and increased heart rate variability. Exercise training can be of bene~t in selected patients with stable New York Heart Association class II or III heart failure.
Cardiac Rehabilitation, 2007