Higher omega-3 index is associated with more rapid heart rate recovery in healthy men and women

BACKGROUND

Previous studies have suggested that omega-3 polyunsaturated fatty acids (n-3 PUFA) can favorably influence cardiac autonomic tone. However, data regarding n-3 PUFA status and heart rate recovery (HRR) in healthy adults are sparse.

PURPOSE

To examine the association between n-3 PUFA status and HRR.

METHODS

Participants included 13,912 patients who underwent a comprehensive examination at the Cooper Clinic, Dallas TX. Fitness was determined from a maximal exercise test. HRR was calculated by subtracting the heart rate at 1, 3, and 5 min of an active recovery period from the maximal heart rate. Participants were categorized as having a low (<4%), normal (4-8%) or optimal (>8%) Omega-3 Index (O3I) (i.e., erythrocyte levels of eicosapentaenoic and docosahexaenoic acids). Multiple linear regression was used to model the association between O3I and HRR adjusting for age, maximal METs, body mass index, and smoking by sex.

RESULTS

Higher categories of O3I were associated with greater HRR at 1 min (men: 23.7, 23.9, 24.6 beats/min; women: 23.9, 24.6, 25.9 and 3 min (men: 52.4, 52.9, 53.6 beats/min; women: 51.9, 53.4, 54.6), p trend <0.01 for all. Corresponding HRR at 5 min were (men: 60.0, 60.2, 60.7 beats/min, p trend=0.09; women: 59.4, 60.8, 61.6, p trend <0.001). The HRR gradients across O3I categories were steeper in women than men at 1, 3, and 5 min (p<0.03 for all sex x O3I category interactions with HRR).

CONCLUSIONS

A direct relationship between HRR and O3I values was observed in both men and women, with a steeper gradient in women. These findings suggest a potential cardioprotective mechanism for n-3 PUFA.

The Association of Self-Reported Muscle-Strengthening Activities With Carotid Intima-Media Thickness in Older Adults: Cooper Center Longitudinal Study

The purpose of the current investigation was to examine the cross-sectional associations of participation in muscle-strengthening activities (MSAs) with carotid intima-media thickness (CIMT) among older adults. The data are from 2,557 older adult participants enrolled in an observational cohort who reported no history of cardiovascular disease. MSA was determined using a questionnaire. Carotid ultrasound was performed to measure the CIMT of the common carotid artery bilaterally. Logistic regression models were constructed to estimate the association of MSA with CIMT after adjustment for potential confounders. The participants were aged 68.6 ± 7.0 years, and the majority were male (71.7%) and White (96.5%); 18% had abnormal CIMT. Meeting the physical activity guidelines for MSA was inversely associated with abnormal CIMT after adjustment for age and sex. However, this observed inverse relation became statistically null after further adjustment for cardiovascular disease risk factors, including aerobic physical activity.

The Association of Physical Activity With Carotid Intima Media Thickening in a Healthy Older Population: Cooper Center Longitudinal Study

The purpose of this study was to examine the association between self-reported physical activity (PA) and mean common carotid artery intima-media thickness (CCA IMT) among older adults. The data are from 1,811 Cooper Center Longitudinal Study participants, who were aged ≥60 years, with no history of cardiovascular disease. A medical history questionnaire was used to assess PA. Carotid ultrasound was performed to measure CCA IMT and the presence of plaque and stenosis. Logistic regression models were constructed to estimate the association between PA and CCA IMT after adjustment for covariates. The participants were aged 69.2 ± 5.9 years, and the majority were male (73.3%) and White (96.7%). The odds ratio of abnormal thickening of CCA IMT was 0.72 (95% confidence interval [0.54, 0.96]) in physically active participants (≥500 metabolic equivalent·min/week) after adjustment for covariates. In the current study, meeting PA guidelines in older adulthood was associated with lower odds of abnormal thickening of CCA IMT.

Association of All-Cause and Cardiovascular Mortality With High Levels of Physical Activity and Concurrent Coronary Artery Calcification

Importance

Few data are available to guide clinical recommendations for individuals with high levels of physical activity in the presence of clinically significant coronary artery calcification (CAC).

Objective

To assess the association among high levels of physical activity, prevalent CAC, and subsequent mortality risk.

Design, Setting, and Participants

The Cooper Center Longitudinal Study is a prospective observational study of patients from the Cooper Clinic, a preventive medicine facility. The present study included participants seen from January 13, 1998, through December 30, 2013, with mortality follow-up through December 31, 2014. A total of 21 758 generally healthy men without prevalent cardiovascular disease (CVD) were included if they reported their physical activity level and underwent CAC scanning. Data were analyzed from September 26, 2017, through May 2, 2018.

Exposures

Self-reported physical activity was categorized into at least 3000 (n = 1561), 1500 to 2999 (n = 3750), and less than 1500 (n = 16 447) metabolic equivalent of task (MET)-minutes/week (min/wk). The CAC scores were categorized into at least 100 (n = 5314) and less than 100 (n = 16 444) Agatston units (AU).

Main Outcomes and Measures

All-cause and CVD mortality collected from the National Death Index Plus.

Results

Among the 21 758 male participants, baseline mean (SD) age was 51.7 (8.4) years. Men with at least 3000 MET-min/wk were more likely to have prevalent CAC of at least 100 AU (relative risk, 1.11; 95% CI, 1.03-1.20) compared with those accumulating less physical activity. In the group with physical activity of at least 3000 MET-min/wk and CAC of at least 100 AU, mean (SD) CAC level was 807 (1120) AU. After a mean (SD) follow-up of 10.4 (4.3) years, 759 all-cause and 180 CVD deaths occurred, including 40 all-cause and 10 CVD deaths among those with physical activity of at least 3000 MET-min/wk. Men with CAC of less than 100 AU and physical activity of at least 3000 MET-min/wk were about half as likely to die compared with men with less than 1500 MET-min/wk (hazard ratio [HR], 0.52; 95% CI, 0.29-0.91). In the group with CAC of at least 100 AU, men with at least 3000 MET-min/wk did not have a significant increase in all-cause mortality (HR, 0.77; 95% CI, 0.52-1.15) when compared with men with physical activity of less than 1500 MET-min/wk. In the least active men, those with CAC of at least 100 AU were twice as likely to die of CVD compared with those with CAC of less than 100 AU (HR, 1.93; 95% CI, 1.34-2.78).

Conclusions and Relevance

This study suggests there is evidence that high levels of physical activity (≥3000 MET-min/wk) are associated with prevalent CAC but are not associated with increased all-cause or CVD mortality after a decade of follow-up, even in the presence of clinically significant CAC levels.

Functional Movement Screening Performance and Association With Key Health Markers in Older Adults

Farrell, SW, Pavlovic, A, Barlow, CE, Leonard, D, DeFina, JR, Willis, BL, DeFina, LF, and Haskell, WL. Functional movement screening performance and association with key health markers in older adults. J Strength Cond Res XX(X): 000-000, 2019-We examined Functional Movement Screening (FMS) performance and associations with key health markers among adults aged 55 years or older. Apparently healthy men (n = 425) and women (n = 158) completed a preventive medical examination between 2013 and 2018. Subjects were grouped by age and sex to determine mean scores for individual FMS items as well as total FMS score. We examined partial correlations between total FMS score and key health markers. We computed odds ratios (ORs) for having a total FMS score ≤14. The mean FMS scores for men and women were 11.7 ± 2.8 and 11.9 ± 2.3, respectively. Several differences were found between men who participated in FMS (takers) compared with FMS nontakers, whereas women FMS takers were generally similar to women FMS nontakers. After controlling for age, sex, and smoking, FMS scores were directly associated with physical activity (PA), cardiorespiratory fitness, frequency of resistance training, serum vitamin D, omega-3 index, low-density lipoprotein, and high-density lipoprotein (HDL)-cholesterol, and were inversely associated with body mass index (BMI), waist circumference (WC), blood glucose, HbA1c, and metabolic syndrome (p ≤ 0.02 for each). Adjusted OR for scoring ≤14 was significantly greater for those who were BMI and WC-obese, those with metabolic syndrome, those with low HDL-cholesterol, and those not meeting current PA guidelines. This study provides characteristics and mean values for FMS in a large older population and demonstrates that FMS performance is associated with key health markers. Prospective studies of older adults are needed to determine the utility of FMS in predicting future musculoskeletal injury and other chronic disease-related health outcomes.

Traditional signs and symptoms commonly attributed to hypogonadism do not correlate with testosterone levels: the Cooper Center Longitudinal Study Experience

Evidence suggests that substantial testosterone therapy is occurring without checking levels of testosterone, presumably based on the presence of symptoms alone. We sought to explore the relationship between total testosterone level and non-specific symptoms, metabolic abnormalities, and sexual dysfunction associated with hypogonadism. This cross-sectional study included 2994 generally healthy men aged 50-79 years examined at a preventive medicine clinic in Dallas, TX from January 2012 to March 2016. Symptoms of hypogonadism were assessed. Screening morning total testosterone levels were measured and categorized into low (<250 ng/dL), low normal (250-399 ng/dL), and normal (≥400 ng/dL). Multiple logistic regression models were used to test the associations between total testosterone and signs and symptoms of hypogonadism. When considering symptoms and signs of hypogonadism, only decreased libido (OR 1.31, 95% CI 1.00 to 1.70), fasting glucose ≥100 mg/dL (OR 1.47, CI 1.15 to 1.88), and hemoglobin A1c over 6% (OR 1.47, 95% CI 1.06 to 2.03) were associated with increased odds of low testosterone after adjustment for age, body mass index, and cardiorespiratory fitness. Testosterone levels were not associated with fatigue, depression, or erectile dysfunction in our study (p>0.6). In this preventive medicine cohort, symptoms commonly attributed to testosterone deficiency were not associated with low total testosterone levels.

Cardiorespiratory Fitness, Different Measures of Adiposity, and Cardiovascular Disease Mortality Risk in Women

Background: Associations among cardiorespiratory fitness (CRF), different adiposity exposures, and cardiovascular disease (CVD) mortality in women are not well defined. Materials and Methods: A total of 19,838 women completed a baseline examination between 1971 and 2013. Measures included body mass index (BMI), waist circumference (WC), waist-to-height (W:HT) ratio, skinfold-derived percent body fat (% Fat), and CRF estimated from a maximal treadmill test. CRF categories were low (quintile 1), moderate (quintiles 2-3), and high (quintiles 4-5); standard cut points were used for adiposity exposures. Hazard ratios (HRs) were estimated using Cox regression. Results: During a mean follow-up period of 19.2 ± 10.3 years, 391 cardiovascular deaths occurred. HRs (95% confidence interval) for CVD in moderate and low CRF groups, using high CRF as the referent, were 1.87 (1.46-2.38) and 2.54 (1.93-3.35), respectively (p trend <0.001). HRs of obese women within each adiposity exposure were higher when compared with normal-weight women (p ≤ 0.03). Joint associations of CRF × adiposity showed a positive trend in CVD mortality across decreasing categories of CRF within each category of W:HT and % Fat, as well as within the normal and overweight BMI categories and the normal WC category (p ≤ 0.03 for each). Conclusion: Higher levels of CRF are associated with lower CVD mortality risk in women, and predict lower risk of CVD mortality in normal-weight women and in obese women. Using different measures of adiposity to predict CVD mortality risk in women may be misleading unless CRF is taken into account. These results support the American Heart Association (AHA) recommendation for including CRF as a clinical vital sign.

Metabolic Syndrome and Cognitive Impairment among High Socioeconomic, Nondemented Older US Adults

OBJECTIVES

Nondemented cognitive impairment (CI) presents opportunities for early interventions among individuals at risk for dementia. Identification of modifiable determinants is paramount to the development of effective clinical interventions. Metabolic syndrome (MetS) was theorized as a risk factor, but current research yields inconsistent findings. Few studies have examined the association between MetS and CI among US populations, and global results may be ungeneralizable. We investigated the MetS-CI association among high socioeconomic, nondemented older US adults, examining the roles of sociodemographic, clinical, behavioral, and genetic factors.

DESIGN

Cross-sectional.

SETTING

Cooper Clinic of Dallas, Texas: Cooper Center Longitudinal Study (2009-2017).

PARTICIPANTS

A total of 5200 dementia-free older adult Cooper Clinic patients.

MEASUREMENTS

CI was detected with a Montreal Cognitive Assessment (MoCA) score lower than 26. MetS was established based on National Cholesterol Education Program Adult Treatment Panel guidelines. Unadjusted and multivariable log-binomial regression were used to assess the MetS-CI association, with modification assessment by age, sex, education, cardiorespiratory fitness (CRF), and apolipoprotein-ε4 carrier status (APOE-ε4).

RESULTS

MetS was not associated with CI when adjusting for age, sex, minority status, education, and marital status (prevalence ratio [PR] = 1.09; 95% confidence interval = .97-1.23) or when additionally adjusting for body mass index, CRF, alcohol consumption, current smoking status, and APOE-ε4 (PR = 1.07; 95% confidence interval = .80-1.45). The association was not modified by age, sex, CRF, or APOE-ε4 (P for interaction >.05).

CONCLUSION

In contrast with some global and US studies, MetS and CI were not associated among our study population of nondemented older US adults. MetS may not be a suitable intervention target for poor cognitive outcomes among high socioeconomic older US adults, although separate MetS components may have different recommendations. Future studies should explore more diverse older US populations. If replicated, these findings would inform clinical efforts to reduce the burden of poor cognitive outcomes in the United States.

The association of midlife cardiorespiratory fitness with later life carotid atherosclerosis: Cooper Center Longitudinal Study

BACKGROUND AND AIMS

While numerous cross-sectional studies have demonstrated an inverse relationship between cardiorespiratory fitness (CRF) and carotid atherosclerosis in middle age, much less is known about the association of midlife CRF with carotid atherosclerosis in later life.

METHODS

We studied 1094 participants, free of cardiovascular disease, who completed a maximal exercise test (GXT) for an objective measure of CRF between ages 40 and 59 and carotid ultrasound after the age of 59, with at least five years between studies. Carotid intima media thickness was measured. Assessments were also made regarding the presence of plaque and percent stenosis in four regions: common carotid, bulb, internal carotid and external carotid arteries. Multivariable logistic regression models were constructed to estimate the association of CRF with carotid artery disease.

RESULTS

At the time of GXT and carotid scan, participants were aged 50.7 ± 5.7 years and 69.3 ± 6.4 years, respectively. Almost half of participants had high midlife CRF (48.6%); 41.3% and 10.1% had moderate and low CRF, respectively. Over a mean follow-up period of 18.6 ± 8.5 years, the odds of having carotid artery disease in later life in the high CRF group was 0.50 (95% CI: 0.29-0.87) compared with the low CRF group. Each 1 MET increase in CRF was associated with 10% lower odds of having carotid artery disease (OR = 0.89, 95% CI: 0.80-0.98).

CONCLUSIONS

Midlife CRF was inversely associated with carotid artery disease measured almost two decades later. This may represent a mechanistic link between high midlife CRF and reduced risk of stroke in later life.

Association of Midlife Cardiorespiratory Fitness With Incident Depression and Cardiovascular Death After Depression in Later Life

IMPORTANCE

Cardiorespiratory fitness (hereinafter referred to as fitness) as estimated by exercise testing is a modifiable risk factor independently associated with chronic diseases, cardiovascular disease (CVD) events, and mortality, but the association of fitness at midlife with incidence of later-life depression and the risk of CVD mortality after a depression diagnosis is unknown.

OBJECTIVE

To determine whether fitness measured in midlife would be inversely associated with later-life CVD mortality with antecedent depression.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study at a single-center, community-based preventive medicine clinic was performed as part of the Cooper Center Longitudinal Study. Data were collected from January 13, 1971, through December 31, 2009, and analyzed from October 6, 2015, through August 14, 2017. Participants included generally healthy men and women who presented for preventive medicine examinations at midlife and who were eligible for Medicare from 1999 to 2010. Those with a self-reported history of depression, myocardial infarction, or stroke at examination were excluded.

EXPOSURES

Objective midlife fitness estimated from results of treadmill exercise testing.

MAIN OUTCOMES AND MEASURES

Depression diagnosis from Medicare claims files using established algorithms and CVD mortality from National Death Index records.

RESULTS

A total of 17 989 participants (80.2% men) with a mean (SD) age of 50.0 (8.7) years were included. After 117 218 person-years of Medicare follow-up, 2701 depression diagnoses, 610 deaths due to CVD without prior depression, and 231 deaths due to CVD after depression were observed. A high level of fitness in midlife was associated with a 16% lower risk of depression (hazard ratio [HR], 0.84; 95% CI, 0.74-0.95) compared with a low level of fitness. A high fitness level was also associated with a 61% lower risk of death due to CVD without depression (HR, 0.39; 95% CI, 0.31-0.48) compared with a low level of fitness. After a diagnosis of depression, a high fitness level was associated with a 56% lower risk of death due to CVD (HR, 0.44; 95% CI, 0.31-0.64) compared with a low fitness level.

CONCLUSIONS AND RELEVANCE

Midlife fitness is associated with a lower risk of later-life depression, CVD mortality, and CVD mortality after incident later-life depression. These findings suggest the importance of midlife fitness in primary prevention of depression and subsequent CVD mortality in older age and should encourage physicians to consider fitness and physical activity in promoting healthy aging.

The association between serum vitamin d level and cognitive function in older adults: Cooper Center Longitudinal Study

Low blood level of vitamin D and low physical activity have been linked to the development of cognitive impairment in older adults. The purpose of the present study was to examine the relationship between serum vitamin D and cognition as measured via the Montreal Cognitive Assessment (MoCA) in a healthy, older population. The study sample consisted of 4358 patients from the Cooper Clinic in Dallas, TX. All participants underwent a maximal graded exercise test to determine cardiorespiratory fitness (CRF). Cognitive impairment was defined as a MoCA score <25. Low vitamin D status was defined as serum 25-hydroxyvitamin D <30 ng/mL. Multivariable logistic regression analysis was employed to evaluate the association between vitamin D blood level and MoCA score. A low MoCA score was directly associated with higher age (OR: 1.75, 95% CI: 1.53, 1.99), and inversely associated with female sex (OR: 0.63, 95% CI: 0.51, 0.77), and years of education (OR: 0.87, 95% CI: 0.84, 0.91). When controlling for significant predictors (age, sex, and education), the low vitamin D group had a significantly greater likelihood of having a low MoCA score (OR: 1.26, 95% CI: 1.04, 1.51). The vitamin D effect remained significant when CRF was added to the model (OR: 1.23, 95% CI: 1.02, 1.48). In conclusion, low vitamin D was shown to be associated with cognitive impairment. Therefore, preventive measures such as vitamin D supplementation may play a protective role in memory loss and/or age-associated cognitive decline.

The Relationship between Cardiorespiratory Fitness and Montreal Cognitive Assessment Scores in Older Adults

BACKGROUND

Relatively little is known regarding the association between objective measures of physical function such as cardiorespiratory fitness (CRF) and cognitive function tests in healthy older adults.

OBJECTIVE

To evaluate the relationship between CRF and cognitive function in adults aged 55 and older.

METHODS

Between 2008 and 2017, 4,931 men and women underwent a comprehensive preventive physical exam at the Cooper Clinic in Dallas, Texas. CRF was determined by duration of a maximal treadmill exercise test. Cognitive function was evaluated with the Montreal Cognitive Assessment (MoCA). In a multivariate model, adjusted odds ratios with 95% confidence intervals for MoCA scores < 26 (i.e., cognitive impairment) were determined by using CRF as both a continuous and a categorical variable.

RESULTS

The mean age of the sample was 61.0 ± 6.0 years; mean maximal MET values were 10.0 ± 2.2. Mean MoCA scores were 26.9 ± 2.2; 23.4% of the sample had MoCA scores indicative of cognitive impairment. The odds ratio for cognitive impairment was 0.93 (0.88-0.97) per 1-MET increment in CRF. When examined as a categorical variable, and using the lowest CRF quintile as the referent, there was a significantly reduced likelihood for cognitive impairment across the remaining ordered CRF categories (p trend = 0.004).

CONCLUSION

The association between CRF and MoCA score in older adults suggests that meeting or exceeding public health guidelines for physical activity is likely to increase CRF in low fit individuals, maintain CRF in those with a moderate to high level of CRF, and thereby help to maintain cognitive function in healthy older adults.

Type 2 diabetes is associated with loss of HDL endothelium protective functions

Aims/Hypothesis

One of the hallmarks of diabetes is impaired endothelial function. Previous studies showed that HDL can exert protective effects on endothelium stimulating NO production and protecting from inflammation and suggested that HDL in obese people with diabetes and dyslipidemia may have lower endothelial protective function. We aimed to investigate whether type 2 diabetes impairs HDL endothelium protective functions in people with otherwise normal lipid profile.

Methods

In a case-control study (n = 41 per group) nested in the Cooper Center Longitudinal Study we tested the ability of HDL to protect endothelium by stimulating endothelial nitric oxide synthase activity and suppressing NFκB-mediated inflammatory response in endothelial cells. In parallel we measured HDL protein composition, sphinogosine-1-phosphate and P-selectin.

Results

Despite similar levels of plasma HDL-C the HDL in individuals with type 2 diabetes lost almost 40% of its ability to stimulate eNOS activity (P<0.001) and 20% of its ability to suppress TNFα-dependent NFκB-mediated inflammatory response in endothelial cells (P<0.001) compared to non-T2D controls despite similar BMI and lipid profile (HDL-C, LDL-C, TC, TG). Significantly, the ability of HDL to stimulate eNOS activity was negatively associated with plasma levels of P-selectin, an established marker of endothelial dysfunction (r = −0.32, P<0.001). Furthermore, sphingosine-1-phosphate (S1P) levels were decreased in diabetic plasma (P = 0.017) and correlated with HDL-mediated eNOS activation.

Conclusions/Interpretations

Collectively, our data suggest that HDL in individuals with type 2 diabetes loses its ability to maintain proper endothelial function independent of HDL-C, perhaps due to loss of S1P, and may contribute to development of diabetic complications.

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.

Moderate to High Levels of Cardiorespiratory Fitness Attenuate the Effects of Triglyceride to High-Density Lipoprotein Cholesterol Ratio on Coronary Heart Disease Mortality in Men

OBJECTIVE

To examine the prospective relationships among cardiorespiratory fitness (CRF), fasting blood triglyceride to high density lipoprotein cholesterol ratio (TG:HDL-C), and coronary heart disease (CHD) mortality in men.

METHODS

A total of 40,269 men received a comprehensive baseline clinical examination between January 1, 1978, and December 31, 2010. Their CRF was determined from a maximal treadmill exercise test. Participants were divided into CRF categories of low, moderate, and high fit by age group and by TG:HDL-C quartiles. Hazard ratios for CHD mortality were computed using Cox regression analysis.

RESULTS

A total of 556 deaths due to CHD occurred during a mean ± SD of 16.6±9.7 years (669,678 man-years) of follow-up. A significant positive trend in adjusted CHD mortality was shown across decreasing CRF categories (P for trend<.01). Adjusted hazard ratios were significantly higher across increasing TG:HDL-C quartiles as well (P for trend<.01). When grouped by CRF category and TG:HDL-C quartile, there was a significant positive trend (P=.04) in CHD mortality across decreasing CRF categories in each TG:HDL-C quartile.

CONCLUSION

Both CRF and TG:HDL-C are significantly associated with CHD mortality in men. The risk of CHD mortality in each TG:HDL-C quartile was significantly attenuated in men with moderate to high CRF compared with men with low CRF. These results suggest that assessment of CRF and TG:HDL-C should be included for routine CHD mortality risk assessment and risk management.

Lifelong Physical Activity Regardless of Dose Is Not Associated With Myocardial Fibrosis

BACKGROUND

Recent reports have suggested that long-term, intensive physical training may be associated with adverse cardiovascular effects, including the development of myocardial fibrosis. However, the dose-response association of different levels of lifelong physical activity on myocardial fibrosis has not been evaluated.

METHODS AND RESULTS

Seniors free of major chronic illnesses were recruited from predefined populations based on the consistent documentation of stable physical activity over >25 years and were classified into 4 groups by the number of sessions/week of aerobic activities ≥30 minutes: sedentary (group 1), <2 sessions; casual (group 2), 2 to 3 sessions; committed (group 3), 4 to 5 sessions; and Masters athletes (group 4), 6 to 7 sessions plus regular competitions. All subjects underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging, including late gadolinium enhancement assessment of fibrosis. Ninety-two subjects (mean age 69 years, 27% women) were enrolled. No significant differences in age or sex were seen between groups. Median peak oxygen uptake was 25, 26, 32, and 40 mL/kg/min for groups 1, 2, 3, and 4, respectively. Cardiac magnetic resonance imaging demonstrated increasing left ventricular end-diastolic volumes, end-systolic volumes, stroke volumes, and masses with increasing doses of lifelong physical activity. One subject in group 2 had late gadolinium enhancement in a noncoronary distribution, and no subjects in groups 3 and 4 had evidence of late gadolinium enhancement.

CONCLUSIONS

A lifelong history of consistent physical activity, regardless of dose ranging from sedentary to competitive marathon running, was not associated with the development of focal myocardial fibrosis.