Impact of American-style football participation on vascular function

Concussion burden and later-life cardiovascular risk factors in former professional American-style football players

OBJECTIVE

Mid-life cardiovascular risk factors are associated with later cognitive decline. Whether repetitive head injury among professional athletes impacts cardiovascular risk is unknown. We investigated associations between concussion burden and postcareer hypertension, high cholesterol, and diabetes among former professional American-style football (ASF) players.

METHODS

In a cross-sectional study of 4080 professional ASF players conducted between January 2015 and March 2022, we used an mulitsymptom concussion symptom score (CSS) and the number of loss-of-consciousness (LOC) episodes as a single severe symptom to quantify football-related concussion exposure. Primary outcomes were hypertension, dyslipidemia, and diabetes, defined by current or recommended prescription medication use.

RESULTS

The prevalence of hypertension, high cholesterol, and diabetes among former players (52 ± 14 years of age) was 37%, 34%, and 9%. Concussion burden was significantly associated with hypertension (lowest vs. highest CSS quartile, odds ratio (OR) = 1.99; 95%CI: 1.33-2.98; p < 0.01) and high cholesterol (lowest vs. moderate CSS, OR = 1.46, 95%CI, 1.11-1.91; p < 0.01), but not diabetes. In fully adjusted models, the prevalence of multiple CVD was associated with CSS. These results were driven by younger former players (≤ 40 year of age) in which the odds of hypertension were over three times higher in those in the highest CSS quartile (OR = 3.29, 95%CI: 1.39-7.61; p = 0.01). Results were similar for LOC analyses.

INTERPRETATION

Prior concussion burden is associated with postcareer atherogenic cardiovascular risk profiles among former professional American football players.

Hypertension in Athletes: Clinical Implications and Management Strategies

Hypertension is a leading cardiovascular risk factor in athletes. Sport-specific behaviors including nonsteroidal anti-inflammatory use, stimulant use, and unhealthy diets may promote hypertension among athletes. Strength-trained athletes may be more susceptible to hypertension than endurance-trained athletes, although this may, in part, be due to body size differences and the more potent antihypertensive effects of aerobic exercise. With confirmed hypertension, young athletes require secondary hypertension evaluation while older athletes require full cardiovascular risk stratification. Calcium channel blockers and renin-angiotensin-system inhibitors are often preferred pharmacotherapy agents. Further selection of antihypertensives must include consideration of potential side effects and legality in specific sports.

Healthspan and chronic disease burden among young adult and middle-aged male former American-style professional football players

OBJECTIVE

To examine the relationships between age, healthspan and chronic illness among former professional American-style football (ASF) players.

METHODS

We compared age-specific race-standardised and body mass index-standardised prevalence ratios of arthritis, dementia/Alzheimer's disease, hypertension and diabetes among early adult and middle-aged (range 25-59 years) male former professional ASF players (n=2864) with a comparator cohort from the National Health and Nutrition Examination Survey and National Health Interview Survey, two representative samples of the US general population. Age was stratified into 25-29, 30-39, 40-49 and 50-59 years.

RESULTS

Arthritis and dementia/Alzheimer's disease were more prevalent among ASF players across all study age ranges (all p<0.001). In contrast, hypertension and diabetes were more prevalent among ASF players in the youngest age stratum only (p<0.001 and p<0.01, respectively). ASF players were less likely to demonstrate intact healthspan (ie, absence of chronic disease) than the general population across all age ranges.

CONCLUSION

These data suggest the emergence of a maladaptive early ageing phenotype among former professional ASF players characterised by premature burden of chronic disease and reduced healthspan. Additional study is needed to investigate these findings and their impact on morbidity and mortality in former ASF players and other athlete groups.

Metabolic Alterations Differentiating Cardiovascular Maladaptation from Athletic Training in American-Style Football Athletes

PURPOSE

Metabolomics identifies molecular products produced in response to numerous stimuli, including both adaptive (includes exercise training) and disease processes. We analyzed a longitudinal cohort of American-style football (ASF) athletes, who reliably acquire maladaptive cardiovascular (CV) phenotypes during competitive training, with high-resolution metabolomics to determine whether metabolomics can discriminate exercise-induced CV adaptations from early CV pathology.

METHODS

Matched discovery ( n = 42) and validation ( n = 40) multicenter cohorts of collegiate freshman ASF athletes were studied with longitudinal echocardiography, applanation tonometry, and high-resolution metabolomics. Liquid chromatography-mass spectrometry identified metabolites that changed ( P < 0.05, false discovery rate <0.2) over the season. Metabolites demonstrating similar changes in both cohorts were further analyzed in linear and mixed-effects models to identify those associated with left ventricular mass, tissue-Doppler myocardial E ' velocity (diastolic function), and arterial function (pulse wave velocity).

RESULTS

In both cohorts, 20 common metabolites changed similarly across the season. Metabolites reflective of favorable CV health included an increase in arginine and decreases in hypoxanthine and saturated fatty acids (heptadecanoate, arachidic acid, stearate, and hydroxydecanoate). In contrast, metabolic perturbations of increased lysine and pipecolate, reflective of adverse CV health, were also observed. Adjusting for player position, race, height, and changes in systolic blood pressure, weight, and pulse wave velocity, increased lysine ( β = 0.018, P = 0.02) and pipecolate ( β = 0.018, P = 0.02) were associated with increased left ventricular mass index. In addition, increased lysine ( β = -0.049, P = 0.01) and pipecolate ( β = -0.052, P = 0.008) were also associated with lower E ' (reduced diastolic function).

CONCLUSIONS

ASF athletes seem to develop metabolomic changes reflective of both favorable CV health and early CV maladaptive phenotypes. Whether metabolomics can discriminate early pathologic CV transformations among athletes is a warranted future research direction.

Updated Blood Pressure Guidelines: Implications for Athletes

PURPOSE OF REVIEW

To review the prevalence, short- and long-term impact of exercise on blood pressure, and the evaluation and treatment of hypertension in competitive athletes.

RECENT FINDINGS

Due, in part, to inconsistencies in measurement and the definitions used, the true prevalence of hypertension is unknown as reports range from 0 to 83%. With recent changes in the blood pressure guidelines, the proportion of athletes that meet criteria for elevated blood pressure or stage 1 hypertension has increased dramatically with over one-third of collegiate and professional athletes meeting criteria for hypertension. Data consistently show that American-style football players, particularly linemen, display the highest rates of hypertension. These athletes typically have a larger body mass index, higher body fat percentage, and weight gain in serial follow-up. Many athletes with hypertension have traditional risk factors, and, to date, there is no evidence of a causal relationship between long-term sport participation and increased risk of developing hypertension. Many more athletes now meet criteria for hypertension, given the updated blood pressure guidelines. This should be taken as an opportunity for early intervention, as athletes are not immune to the development of cardiovascular risk factors and disease.

Hypertension and Ventricular-Arterial Uncoupling in Collegiate American Football Athletes

Background

Ventricular–arterial (VA) coupling is defined as the ratio between arterial elastance (EA) and left ventricular elastance (ELV). VA uncoupling, as occurs in hypertensive heart disease, is associated with adverse outcomes. This study sought to determine the relationship between American football (AF)–associated hypertension and VA uncoupling.

Methods and Results

This was a multicenter, longitudinal, and repeated measures observational study of collegiate AF athletes across 3 years of AF participation. Of 200 freshman athletes initially enrolled, 142 (67 Black [47%]/75 White [53%], 58 linemen [41%]/84 nonlinemen [59%]) were prospectively studied with echocardiography and applanation tonometry. Primary echocardiographic VA coupling outcome measures were EA/ELV and ΔEA/ELV, with increased EA/ELV indicating VA uncoupling. Adjusting for race and player position, AF athletes demonstrated increased EA/ELV (mean [95% CI]Δ, 0.10 [0.04–0.15]; P=0.001) and systolic blood pressure (SBP) (mean [95% CI]Δ, 11.4 [8.3–14.5] mm Hg, P<0.001) over their collegiate AF careers. In combination with longitudinal VA uncoupling, hypertension prevalence (including both stage 1 and 2) increased from 54% at baseline to 77% (44% stage 2) at the end of the study period (P<0.001). In multivariable mixed‐effects linear regression analysis, higher SBP (β=0.021, P=0.02), lower E′ (β=−0.010, P=0.03), and worse global longitudinal strain (β=0.036, P<0.001) were associated with higher EA/ELV. Increased SBP (ΔSBP, β=0.029, P=0.02) and worsened global longitudinal strain (Δglobal longitudinal strain, β=0.045, P<0.001) also predicted increased ΔEA/ELV.

Conclusions

VA uncoupling is associated with pathologically increased SBP and subclinical impairments in left ventricular systolic function in collegiate AF athletes, indicating a key mechanism underlying maladaptive cardiovascular phenotypes observed in this population. Future studies analyzing whether targeted clinical interventions improve VA coupling and health outcomes are warranted.

Left ventricular hypertrophy in athletes, a case-control analysis of interindividual variability

BACKGROUND

A variability in cardiac remodeling is observed in athletes regardless of age, sex, body size and sport participated. We sought to investigate whether other individual characteristics could affect the extent of Left ventricular hypertrophy (LVH).

METHODS

From 2120 consecutive Olympic athletes, those with LVH (defined as LV Wall thickness ≥ 13 mm) were matched 1:1 by age, gender, body surface area and type of sport with non-LVH Athletes. Clinical and Echocardiographic variables were compared.

RESULTS

48 athletes with LVH (2.3%) and 48 matched non-LVH athletes were identified. LVH Athletes had higher body weight (90 ± 18 vs 81 ± 11Kg; p = 0.006) body mass index (26 ± 2 vs 24 ± 2 Kg/m2; p < 0.001) and body fat percentage (15 ± 7% vs 12 ± 4%; p = 0.016) compared to non-LVH Athletes. They also had higher systolic (123 ± 1 vs 116 ± 11 mmHg; p = 0.002) and diastolic blood pressure (76 ± 8 vs 71 ± 9 mmHg; p = 0.002). On exercise testing, LVH Athletes reached a lower index workload (3.7 ± 0.9 vs 4.1 ± 0.8 W/Kg; p = 0.013) and a higher peak diastolic blood pressure (79 ± 10 vs 74 ± 11 mmHg; p = 0.012) than those without LVH. Binary logistic regression analysis showed that diastolic blood pressure (OR 1.052; 95% CI from 1.011 to 1.130; p = 0.020) and BMI (OR 1.220; 95% CI from 1.016 to 1.465; p = 0.033) had the strongest association with LVH as categorical variable.

CONCLUSIONS

Our study showed that increased blood pressure at rest and during exercise, together with larger body weight, body mass and fat percentage are associated with a higher degree of LVH, which is not associated with a greater physical performance and therefore possibly disproportionate to the sport activity.

Exercise-Induced Cardiovascular Adaptations and Approach to Exercise and Cardiovascular Disease: JACC State-of-the-Art Review

The role of the sports cardiologist has evolved into an essential component of the medical care of athletes. In addition to the improvement in health outcomes caused by reductions in cardiovascular risk, exercise results in adaptations in cardiovascular structure and function, termed exercise-induced cardiac remodeling. As diagnostic modalities have evolved over the last century, we have learned much about the healthy athletic adaptation that occurs with exercise. Sports cardiologists care for those with known or previously unknown cardiovascular conditions, distinguish findings on testing as physiological adaptation or pathological changes, and provide evidence-based and "best judgment" assessment of the risks of sports participation. We review the effects of exercise on the heart, the approach to common clinical scenarios in sports cardiology, and the importance of a patient/athlete-centered, shared decision-making approach in the care provided to athletes.

Association between race and maladaptive concentric left ventricular hypertrophy in American-style football athletes

OBJECTIVES

American-style football (ASF) athletes are at risk for the development of concentric left ventricular hypertrophy (C-LVH), an established cardiovascular risk factor in the general population. We sought to address whether black race is associated with acquired C-LVH in collegiate ASF athletes.

METHODS

Collegiate ASF athletes from two National Collegiate Athletic Association Division-I programmes were recruited as freshmen between 2014 and 2019 and analysed over 3 years. Demographics (neighbourhood family income) and repeated clinical characteristics and echocardiography were recorded longitudinally at multiple timepoints. A mixed-modelling approach was performed to evaluate acquired C-LVH in black versus white athletes controlling for playing position (linemen (LM) and non-linemen (NLM)), family income, body weight and blood pressure.

RESULTS

At baseline, black athletes (N=124) were more often NLM (72% vs 54%, p=0.005) and had lower median neighbourhood family income ($54 119 vs $63 146, p=0.006) compared with white athletes (N=125). While both black and white LM demonstrated similar increases in C-LVH over time, among NLM acquired C-LVH was more common in black versus white athletes (postseason year-1: N=14/89 (16%) vs N=2/68 (3%); postseason year-2: N=9/50 (18%) vs N=2/32 (6%); postseason year-3: N=8/33 (24%) vs N=1/13 (8%), p=0.005 change over time). In stratified models, black race was associated with acquired C-LVH in NLM (OR: 3.70, 95% CI 1.12 to 12.21, p=0.03) and LM was associated with acquired C-LVH in white athletes (OR: 3.40, 95% CI 1.03 to 11.27, p=0.048).

CONCLUSIONS

Independent of family income and changes in weight and blood pressure, black race was associated with acquired C-LVH among collegiate ASF NLM and LM was associated with acquired C-LVH in white athletes.

Exercise Training Duration and Intensity Are Associated With Thicker Carotid Intima-Media Thickness but Improved Arterial Elasticity in Active Children and Adolescents

Even though exercise generally has a positive effect on health, intensive exercise can have adverse effects on the vascular system of adults. This study aimed to investigate the association between training duration and intensity and vascular structure and function in 427 physically active children and adolescents (14.0 ± 1.94 years). In this study, we examined carotid intima-media thickness (cIMT), carotid diameter, and cIMT:diameter-ratio as parameters of carotid arterial structure and arterial compliance (AC), stiffness index β (β), elastic modulus (Ep), and carotid pulse wave velocity (PWVβ) as parameters of carotid arterial function with high-resolution ultrasound. We collected central systolic blood pressure (cSBP) and aortic pulse wave velocity (aPWV) as parameters of central arterial stiffness with an oscillometric device. We used the MoMo Physical Activity Questionnaire to record training duration and intensity. Training duration (p = 0.022) and intensity (p = 0.024) were associated with higher cIMT. Further, training duration was associated with lower central arterial stiffness (cSBP: p = 0.001; aPWV: p = 0.033) and improved AC (p < 0.001). Higher training intensity was related to improved AC (p < 0.001) and larger carotid diameter (p = 0.040). Boys presented thicker cIMT (p = 0.010), improved AC (p = 0.006), and lower central arterial stiffness (cSBP: p < 0.001; aPWV: p = 0.016) associated with higher training duration. Girls presented improved AC (p = 0.023) and lower Ep (p = 0.038) but higher β (p = 0.036) associated with higher training duration. Only boys demonstrated thicker cIMT (p = 0.016) and improved AC (p = 0.002) associated with higher training intensity. A quintile analyses of the training duration revealed thicker cIMT of children and adolescents in Q1 and Q5 than that in Q4 and Q5. Besides, Q1 showed lower cSBP compared to Q4 and Q5. Regarding training intensity, Q5 had thicker cIMT than Q2 and Q3. Although a higher training load is associated with thicker cIMT, the common carotid artery is also more elastic. This suggests that a higher training load leads to a functional adaptation of the carotid artery in youth.

Examining the relationship between arterial stiffness and swim-training volume in elite aquatic athletes

PURPOSE

Factors such as prone body position, hydrostatic pressure, and intermittent breath-holding subject aquatic athletes to unique physical and environmental stressors during swimming exercise. The relationship between exposure to aquatic exercise and both arterial stiffness and wave reflection properties is not well-understood. This study assessed central artery stiffness and wave reflection properties in elite pool-swimmers (SW), long-distance open-water swimmers (OW), and water polo players (WP) to examine the relationship between these variables and aquatic exercise.

METHODS

Athletes competing in SW, OW and WP events at the FINA World Championships were recruited. Carotid-femoral pulse wave velocity, and pulse wave analysis were used to quantify arterial stiffness, and central wave reflection properties.

RESULTS

Athletes undertook differing amounts of weekly swimming distance in training according to their discipline (SW: 40.2 ± 21.1 km, OW: 59.7 ± 28.4 km, WP: 11.4 ± 6.3 km; all p < 0.05). Pulse wave velocity (Males [SW: 6.0 ± 0.6 m/s, OW: 6.5 ± 0.8 m/s, WP: 6.7 ± 0.9 m/s], Females [SW: 5.4 ± 0.6 m/s, OW: 5.3 ± 0.5 m/s, WP: 5.2 ± 0.8 m/s; p = 0.4]) was similar across disciplines for females but was greater in male WP compared to male SW (p = 0.005). Augmentation index (Males [SW: - 3.4 ± 11%, OW: - 9.6 ± 6.4%, WP: 1.7 ± 10.9%], Females [SW: 3.5 ± 13.5%, OW: - 13.2 ± 10.7%, WP: - 2.8 ± 10.7%]) was lower in male OW compared to WP (p = 0.03), and higher in female SW compared to OW (p = 0.002). Augmentation index normalized to a heart rate of 75 bpm was inversely related to weekly swim distance in training (r = - 0.27, p = 0.004).

CONCLUSIONS

This study provides evidence that the central vasculature of elite aquatic athletes differs by discipline, and this is associated with training load.

Season-Long Heart-Rate Variability Tracking Reveals Autonomic Imbalance in American College Football Players

PURPOSE

To track cardiac-autonomic functioning, indexed by heart-rate variability, in American college football players throughout a competitive period.

METHODS

Resting heart rate (RHR) and the natural logarithm root mean square of successive differences (LnRMSSD) were obtained throughout preseason and ∼3 times weekly leading up to the national championship among 8 linemen and 12 nonlinemen. Seated 1-minute recordings were performed via mobile device and standardized for time of day and proximity to training.

RESULTS

Relative to preseason, linemen exhibited suppressed LnRMSSD during camp-style preparation for the playoffs (P = .041, effect size [ES] = -1.01), the week of the national semifinal (P < .001, ES = -1.27), and the week of the national championship (P = .005, ES = -1.16). As a combined group, increases in RHR (P < .001) were observed at the same time points (nonlinemen ES = 0.48-0.59, linemen ES = 1.03-1.10). For all linemen, RHR trended upward (positive slopes, R2 = .02-.77) while LnRMSSD trended downward (negative slopes, R2 = .02-.62) throughout the season. Preseason to postseason changes in RHR (r = .50, P = .025) and LnRMSSD (r = -.68, P < .001) were associated with body mass.

CONCLUSIONS

Heart-rate variability tracking revealed progressive autonomic imbalance in the lineman position group, with individual players showing suppressed values by midseason. Attenuated parasympathetic activation is a hallmark of impaired recovery and may contribute to cardiovascular maladaptations reported to occur in linemen following a competitive season. Thus, a descending pattern may serve as an easily identifiable red flag requiring attention from performance and medical staff.

Improved Carotid Elasticity but Altered Central Hemodynamics and Carotid Structure in Young Athletes

Young athletes most often exceed the physical activity recommendations of the World Health Organization. Therefore, they are of special interest for investigating cardiovascular adaptions to exercise. This study aimed to examine the arterial structure and function of young athletes 12-17 years old and compare these parameters to reference values of healthy cohorts. Carotid intima-media thickness (cIMT), carotid diameter, cIMT÷carotid diameter-ratio (cIDR), arterial compliance (AC), elastic modulus (Ep), β stiffness index (β), and carotid pulse wave velocity (PWVβ) were determined using ultrasound in 331 young athletes (77 girls; mean age, 14.6 ± 1.30 years). Central systolic blood pressure (cSBP) and aortic PWV (aPWV) were measured using the oscillometric device Mobil-O-Graph. Standard deviation scores (SDS) of all parameters were calculated according to German reference values. The 75th and 90th percentiles were defined as the threshold for elevated cIMT and arterial stiffness, respectively. Activity behavior was assessed with the MoMo physical activity questionnaire, and maximum power output with a standard cardiopulmonary exercise test. One-sample t-tests were performed to investigate the significant deviations in SDS values compared to the value "0". All subjects participated in competitive sports for at least 6 h per week (565.6 ± 206.0 min/week). Of the 331 young athletes, 135 (40.2%) had cIMT >75th percentile, 71 (21.5%) had cSBP >90th percentile, and 94 (28.4%) had aPWV>90th percentile. We observed higher cIMT SDS (p < 0.001), cIDR SDS (p = 0.009), and AC SDS (p < 0.001) but lower β SDS (p < 0.001), Ep SDS (p < 0.001), and PWVβ SDS (p < 0.001) compared to the reference cohort. The cSBP SDS (p < 0.001) and aPWV SDS (p < 0.001) were elevated. In conclusion, cIMT and cIDR were higher in young athletes than in a reference cohort. Furthermore, young athletes presented better carotid elasticity and lower arterial stiffness of the carotid artery. However, central arterial stiffness was higher compared to the reference cohort. The thickening of the carotid intima-media complex in combination with a reduction in arterial stiffness indicates a physiological adaptation to exercise in youth.

Brachial and central blood pressure and arterial stiffness in adult elite athletes

Purpose

Measures of arterial stiffness (AS) and central blood pressure (BP) are indicators for cardiovascular health and possess a high prognostic value in the prediction of cardiovascular events. The effects of physical training are widely unexplored in the context of competitive, high-performance sports. Therefore, we aimed to present possible reference values of brachial and central BP and of AS of adult elite athletes compared to a control group.

Methods

A total of 189 subjects participated in this cross-sectional study. Of these were 139 adult elite athletes (70 male, 69 female) performing on top-national and international level, and 50 control subjects (26 male, 24 female). Resting brachial and central BP and aortic pulse wave velocity (PWV) were measured and were compared in terms of sex, sport category, and age of the athletes.

Results

Results show no difference between athletes and controls in any parameter. Women exhibit lower brachial and central BP and AS values compared to men. PWV is positively correlated with age. Evaluation of the parameters according to the different sport categories showed that endurance athletes exhibit lower BP and PWV compared to other athletes.

Conclusions

This study presents brachial and central BP and PWV values of athletes, suggesting that high-performance sport does not negatively impact AS. The proposed reference values might support a more detailed evaluation of elite athlete’s cardiovascular and hemodynamic system and a better assignment to possible risk groups.

Under-appreciated and Overlooked Modes of Exercises on Key Vascular Functions

The arterial system has two primary functions. The conduit function is to transport adequate supply of oxygen and nutrients to the tissues, and the cushioning function is to buffer and cushion the pulsatile pressure exerted by intermittent ventricular contractions. The impairments in these two functions often result from physiological changes characterized by endothelial dysfunction and arterial stiffening. Habitual physical exercise has been advocated to combat these physiological dysfunctions. However, exercise is remarkably diverse, as it can be performed in different media (water, land or snow), seasons (winter or summer), and settings (individual, pair or team). In contrast to mainstream modes of exercise including walking and running, many of the alternative or "minor" forms of exercise have been under-researched by investigators in research fields and overlooked by clinicians and practitioners in clinical settings. It remains largely unknown whether these alternative forms of exercise are associated with favorable changes in arterial stiffness and endothelium-dependent vasodilation. The current review introduces and summarizes research investigations that evaluated the impacts of these under-appreciated and overlooked exercises and their impacts on key markers of vascular functions in humans.

Weight Gain, Hypertension, and the Emergence of a Maladaptive Cardiovascular Phenotype Among US Football Players

Importance

Former US football athletes are at increased risk of cardiovascular (CV) morbidity and mortality compared with the general population and other professional athletes. However, responsible maladaptive CV phenotypes have not been fully characterized.

Objective

To address the emergence and progression of multiple independent factors associated with CV risk across serial years of collegiate US football participation.

Design, Setting, and Participants

Collegiate US football athletes from 2 National Collegiate Athletic Association Division I programs were recruited as freshmen between June 2014 and June 2017 and analyzed at multiple points throughout 3 complete years of collegiate US football participation (until January 2019). Excluded athletes were those who did not complete any season of US football training because of injury, illness, or leaving the team. Factors associated with CV risk assessed clinically, by transthoracic echocardiography, and by vascular applanation tonometry were recorded.

Exposures

The exposure of interest was seasonal US football exposure, including training, competition, and the training environment.

Main Outcomes and Measures

Primary outcome measures were left ventricular mass index and geometry (cardiac structure), early diastolic myocardial relaxation velocity (E'; diastolic function), and pulse-wave velocity (arterial stiffness).

Results

Of 186 individuals recruited as freshmen, 126 athletes were included in analyzed data. Collegiate US football athletes (62 white individuals [49%]; 63 black individuals [50%]; 77 nonlinemen [61%]; 49 linemen [39%]; 126 male individuals [100%]) weighed a mean (SD) of 101.1 (21.0) kg, with a mean systolic blood pressure of 129.1 (11.6) mm Hg at baseline of the freshman season. Adjusting for race, height, and player position, there were significant increases in weight (mean [SE] Δ, 4.74 [0.6] kg; P < .001), systolic blood pressure (mean [SE] Δ, 11.6 [1.6] mm Hg; P < .001), and pulse-wave velocity (mean [SE] Δ, 0.24 [0.09] m/s; P = .007), and significant declines in E' (mean [SE] Δ, -1.7 [0.3] cm/s; P < .001) across 3 years of US football participation. Weight gain was associated with both arterial stiffening (increased pulse-wave velocity, β = 0.01 [SE, 0.004]; P = .003) and the development of concentric left ventricular hypertrophy (odds ratio, 1.09 [95% CI, 1.05-1.14]; P < .001); increased systolic blood pressure was also associated with arterial stiffening (β = 0.01 [SE, 0.003]; P = .007) and the development of concentric left ventricular hypertrophy (odds ratio, 1.04 [95% CI, 1.01-1.07]; P = .02).

Conclusions and Relevance

Collegiate US football athletes who gain weight and develop increased systolic blood pressure levels are at risk for the development of a pathologic CV phenotype characterized by concentric left ventricular hypertrophy, arterial stiffening, and reduced left ventricular diastolic function. Future work aimed at optimizing CV health in this population, who are young but uniquely at risk, is warranted.

Nonsteroidal Anti-inflammatory Drugs and Cardiovascular Risk in American Football

INTRODUCTION

Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with adverse cardiovascular outcomes and reportedly overused in American-style football (ASF). However, assessment of ASF NSAID use in the context of cardiovascular risk has not been performed. We sought to characterize NSAID use patterns and the association with cardiovascular risk in a diverse cohort of high school and collegiate ASF athletes.

METHODS

A total of 226 ASF athletes, 60 endurance athletes, and 63 nonathletic controls were studied pre- and postseason with echocardiography, vascular applanation tonometry, and clinical data assessment. Qualitative NSAID use throughout the season was recorded at postseason.

RESULTS

ASF athletes gained weight (Δ0.86 ± 3.9 kg, P < 0.001), increased systolic blood pressure (SBP, Δ3.1 ± 12 mm Hg, P < 0.001) and pulse wave velocity (Δ0.2 ± 0.6 m·s, P < 0.001), and decreased E' (Δ-1.4 ± 2.8 cm·s, P < 0.001) across one athletic season. Seventy-seven percent (n = 173) of ASF athletes reported that sport-specific NSAID use began in middle school. ASF NSAID use was more frequent with "weekly" (n = 42.19%) and "daily" (n = 32.14%) use compared with endurance athletes (P < 0.001) and controls (P = 0.02). ASF NSAID use increased in parallel with postseason SBP and weights. "Daily" ASF NSAID users demonstrated the highest postseason SBP (137 ± 13 vs 128 ± 13 mm Hg, P = 0.002) and weight (109.0 ± 18.6 vs 95.8 ± 20.5 kg, P = 0.002) compared with "never/rare" users. Adjusting for player position, SBP, pulse wave velocity, and E', increased weight (odds ratio = 1.04, 95% confidence interval = 1.0-1.08, P = 0.037) was associated with more frequent NSAID use.

CONCLUSIONS

Habitual NSAID use commonly begins during adolescence, before full physical maturation, and is associated with cardiovascular risk, particularly increased weight, in ASF athletes. NSAID use frequency should be considered when risk stratifying high-risk ASF athletes.

A career in sport does not eliminate risk of cardiovascular disease: A systematic review and meta-analysis of the cardiovascular health of field-based athletes

OBJECTIVES

To determine the prevalence of cardiovascular disease (CVD) risk factors in current field-based athletes.

DESIGN

Meta-analysis.

METHODS

This review was conducted and reported in accordance with PRISMA and pre-registered with PROSPERO. Articles were retrieved via online database search engines, with no date or language restriction. Studies investigating current field-based athletes (>18years) for CVD risk factors according to the European Society of Cardiology and American Heart Association were screened. Full texts were screened using Covidence and Cochrane criteria. Eligible articles were critically appraised using the AXIS tool. Individual study estimates were assessed by random-effect meta-analyses to examine the overall effect.

RESULTS

This study was ascribed a 1b evidence level, according to the Oxford Centre for Evidence-based Medicine. 41 studies were identified, including 5546 athletes from four sports; American football; soccer; rugby and baseball mean ages: 18-28. Despite participation in sport, increased body mass was associated with increased total cholesterol, low-density lipoprotein, triglycerides, hypertension, systolic blood pressure, and decreased high-density lipoprotein. Linemen had increased prevalence of hypertension compared to non-athletes. Conflicting findings on fasting glucose were prevalent. There were inconsistencies in screening and reporting of CVD risk factors. Sport specific anthropometric demands were associated with elevated prevalence of CVD risk factors, most notably: elevated body mass; dyslipidemia; elevated systolic blood pressure and; glucose.

CONCLUSIONS

There are elevated levels of risk for CVD in some athletes, primarily football players. Lifestyle behaviours associated with elite athleticism, particularly football linemen potentially expose players to greater metabolic and CVD risk, which is not completely offset by sport participation.

Influence of Vigorous Physical Activity on Structure and Function of the Cardiovascular System in Young Athletes-The MuCAYA-Study

Objective: Moderate physical activity (PA) is associated with a reduced risk to develop cardiovascular disease. However, junior athletes exercise between 10 and 20 h a week with intensities exceeding moderate levels by far. In this regard, the cardiovascular system has to increase its work five to six times compared to moderate intensities. This may result in potentially pathological adaptations of the cardiovascular system. The underlying process of vascular adaptations to exercise is yet not fully understood and hardly investigated in junior athletes. An increased blood pressure and pulse wave velocity, ventricular hypertrophy, arrhythmia, and even sudden cardiac death (SCD) has been reported in adult athletes. Studies, examining the cardiovascular system in children, its association to intensity and type of exercise, are rare. Therefore, we present the study protocol of a prospective cross-sectional study that investigates the influence of PA on the cardiovascular system in young athletes.

Methods and Design: Children and adolescents, 7–18 years, presenting for their annual pre-participation screening at the Institute of Preventive Pediatrics, Faculty of Sports and Health Sciences, Technical University of Munich (TUM), are examined in this prospective cross-sectional study. Vascular parameters measured by ultrasound are carotid intima-media thickness (cIMT), vascular stiffness (AC, Ep, β, PWV β), and the vascular diameter (D) to calculate the IMT:Diameter-Ratio (IDR). Cardiac function is evaluated by a 12-lead ECG, and echocardiographic parameters (end-diastolic left ventricular diameter, left ventricular diastolic posterior wall thickness, diastolic septal thickness, left ventricular mass and relative wall thickness, ejection fraction, and shortening fraction). A cardiopulmonary exercise test is performed on a bicycle ergometer, muscular strength is assessed with the handgrip test, and physical activity with the MoMo questionnaire.

Discussion: It is essential to follow young athletes over the course of their career in order to detect pathophysiological changes in the myocardium as soon as possible. If these changes are preceded or followed by changes in vascular structure and function is not known yet. Therefore, we present the study protocol of the Munich Cardiovascular adaptations in young athletes study (MuCAYA-Study) which investigates the association between vascular and cardiac adaptation to intensive exercise in junior athletes.

Vascular health determinants in children

BACKGROUND

The epidemic of cardiovascular disease (CVD) in the twentieth century generated numerous population-based surveys. These results clearly demonstrate that many factors are causally related to the development of atherosclerosis. Eighty percent of the CVD can be explained by smoking, high blood pressure, deterioration of lipid and glucose metabolism and physical inactivity. CVD is a disease that becomes clinically apparent in adults. However, it is undisputed that this disease develops over a long period of time due to progressive, subclinical changes in the cardiovascular system. The early manifestation of arteriosclerosis correlates with traditional risk factors.

METHODS

This brief report focusses on determinates of vascular health. It describes non-invasive diagnostic methods such as oscillometric analysis of pulse wave velocity (PWV), ultrasound measurement of carotid structure and function as well as brachial endothelial function. Special attention is paid to possible correlations with physical activity, fitness and exercise.

RESULTS

Non-invasive diagnostic methods to determine vascular health are applicable in children. The influence of physical activity and the relationship between aerobic fitness and arterial compliance (AC) remain controversial. First results in young athletes demonstrated an increased carotid intima-media thickness (cIMT), by revealing arterial elasticity. The mechanism and determinants explaining these adaptations have not been fully explained in young healthy athletes.

CONCLUSIONS

Traditional cardiovascular risk factors act early in life and have a major impact on the development of atherosclerosis. The results underline that the prevention strategies and risk factor control should begin in childhood. The emphasis in the present report lied on the determination of vascular health, analyzing arterial structure and function, using non-invasive diagnostic methods. Vascular health and its relation to obesity, hypertension, physical activity and exercise were emphasized. The harmonization of knowledge and methods would greatly increase the comparability of existing results. To further elucidate the clinical relevance, the mechanisms linking arterial structure and compliance function with physical activity, fitness and exercise need further clinical investigation to enhance early preventive intervention strategies.

Temporal Changes in Cardiovascular Remodeling Associated with Football Participation

PURPOSE

American-style football (ASF) participation rates in the United States are highest among high school (HS) athletes. This study sought to compare the cardiovascular response to HS versus collegiate ASF participation.

METHODS

The ASF participants (HS, n = 61; collegiate, n = 87) were studied at preseason and postseason time points with echocardiography and applanation tonometry. Primary outcome variables included: left ventricular (LV) mass index, LV diastolic function (early relaxation velocity [E']), and arterial stiffness (pulse wave velocity [PWV]).

RESULTS

High school (17.1 ± 0.4 yr) and collegiate ASF participants (18 ± 0.4 yr) experienced similar LV hypertrophy (ΔLV mass HS = 10.5 ± 10 vs collegiate = 11.2 ± 13.6 g·m, P = 0.97). Among HS participants, increases in LV mass were associated with stable diastolic tissue velocities (ΔE' = -0.3 ± 2.9 cm·s, P = 0.40) and vascular function (ΔPWV = -0.1 ± 0.6 m·s, P = 0.13). In contrast, collegiate participants demonstrated a higher burden of concentric LV hypertrophy (21/87, 24% vs 7/61, 11%, P = 0.026) with concomitant reductions in diastolic tissue velocities (ΔE': -2.0 ± 2.7 cm·s, P < 0.001) and increased arterial stiffness (ΔPWV: Δ0.2 ± 0.6 m·s, P = 0.003), changes that were influenced by linemen who had the highest post-season weight (124 ± 10 kg) and systolic blood pressure ([SBP], 138.8 ± 11 mm Hg). In multivariable analyses adjusting for age and ethnicity, body mass was an independent predictor of post-season PWV (β estimate = 0.01, P = 0.04) and E' (β estimate = -0.04, P = 0.05), whereas SBP was an independent predictor of postseason LV mass index (β estimate = 0.18, P = 0.01) and PWV (β estimate = 0.01, P = 0.007).

CONCLUSIONS

The transition from HS to college represents an important physiologic temporal data point after which differential ASF cardiovascular phenotypes manifest. Future work aimed to clarify underlying mechanisms, and the long-term clinical implications of these findings is warranted.

Weight Gain and Health Affliction Among Former National Football League Players

BACKGROUND

Professional American-style football players are among the largest athletes across contemporary sporting disciplines. Weight gain during football participation is common, but the health implications of this early-life weight gain remain incompletely understood. We sought to define weight trajectories of former professional American-style football athletes and to establish their relationship with 5 common health afflictions (cardiovascular disease, cardiometabolic disease, neurocognitive impairment, sleep apnea, and chronic pain).

METHODS

A health survey was distributed to former National Football League (NFL) players. Former players reported body weight at 4 time points (high school, college, professional, and time of survey response) as well as maximal retirement weight. Logistic regression was used to assess associations between weight gain during football participation and health affliction.

RESULTS

In this cohort of former NFL players (n = 3,506, age 53 ± 14 years), mean weight increase from high school to time of survey response was 40 ± 36 pounds, with the majority of weight gain occurring during periods of football participation (high-school-to-college and college-to-professional). The prevalence of health afflictions ranged from 9% (cardiovascular disease) to 28% (chronic pain). Weight gain during football participation was independently associated with risk of multiple later-life health afflictions in models adjusted for football exposure, lifestyle variables, and post-career weight gain.

CONCLUSIONS

Early-life weight gain among American-style football athletes is common and is associated with risk of adverse health profiles during later-life. These findings establish football-associated weight gain as a key predictor of post-career health and raise important questions about the central role of targeted weight gain in this population.

Sleep-Disordered Breathing and Cardiovascular Correlates in College Football Players

This study sought to determine the cardiovascular physiologic correlates of sleep-disordered breathing (SDB) in American-style football (ASF) participants using echocardiography, vascular applanation tonometry, and peripheral arterial tonometry. Forty collegiate ASF participants were analyzed at pre- and postseason time points with echocardiography and vascular applanation tonometry. WatchPAT (inclusive of peripheral arterial tonometry) used to assess for SDB was then performed at the postseason time point. Twenty-two of 40 (55%) ASF participants demonstrated SDB with an apnea-hypopnea index (pAHI) ≥5. ASF participants with SDB were larger (109 ± 20 vs 92 ± 14 kg, p = 0.004) and more likely linemen position players (83% vs 50%, p = 0.03). Compared with those without SDB, ASF participants with SDB demonstrated relative impairments in left ventricular diastolic and vascular function as reflected by lower lateral e' (14 ± 3 vs 17 ± 3 cm/s, p = 0.007) and septal e' (11 ± 2 vs 13 ± 2 cm/s, p = 0.009) tissue velocities and higher pulse wave velocity (5.4 ± 0.9 vs 4.8 ± 0.5 m/s, p = 0.02). In the total cohort, there were significant positive correlations between pAHI and pulse wave velocity (r = 0.42, p = 0.008) and inverse correlations between pAHI and the averaged e' tissue velocities (r = -0.42, p = 0.01). In conclusion, SDB is highly prevalent in youthful collegiate ASF participants and associated with relative impairments in cardiac and vascular function. Targeted efforts to identify youthful populations with SDB, including ASF participants, and implement SDB treatment algorithms, represent important future clinical directives.

Exercise and Competitive Sport: Physiology, Adaptations, and Uncertain Long-Term Risks

OPINION STATEMENT

The benefits of regular and moderate exercise training on cardiovascular outcomes have been well established. In addition, strenuous exercise training leads to corollary cardiac structural and functional adaptations that are sport-specific and facilitate athletic performance. In this review, the normal physiologic and hemodynamic changes that occur during exercise and the subsequent differential exercise-induced cardiac remodeling patterns that develop will be discussed. Paradoxically, recent data have raised concern about the long-term impact of higher doses of physical activity and exercise on mortality and cardiovascular health outcomes. We will discuss important aspects of these controversial data and review the supporting evidence as well as the limitations of prior research. Specifically, we will address the association between high levels of exercise and relative reductions in overall mortality, increased risk of atrial fibrillation, arrhythmogenic cardiac remodeling, and accelerated coronary artery calcifications. For the practitioner, this review aims to detail these contemporary sports cardiology controversies and highlights the critical need to incorporate shared decision making with the athlete in dealing with the uncertainties that exist. Finally, we will discuss key "athlete-specific" variables that should be considered in the design of future important research in this arena.

Prevalence and Management of Systemic Hypertension in Athletes

The aim of the present study was to evaluate the prevalence, determinants, and clinical management of systemic hypertension in a large cohort of competitive athletes: 2,040 consecutive athletes (aged 25 ± 6 years, 64% men) underwent clinical evaluation including blood test, electrocardiogram, exercise test, echocardiography, and ophthalmic evaluation. Sixty-five athletes (3%) were identified with hypertension (men = 57; 87%) including 5 with a secondary cause (thyroid dysfunction in 3, renal artery stenosis in 1, and drug induced in 1). The hypertensive athletes had greater left ventricular hypertrophy and showed more often a concentric pattern than normotensive ones. Moreover, they showed a mildly reduced physical performance and were characterized by a higher cardiovascular risk profile compared with normotensive athletes. Multivariate logistic regression analysis showed that family hypertension history (odds ratio 2.05; 95% confidence interval 1.21 to 3.49; p = 0.008) and body mass index (odds ratio 1.32; 95% confidence interval 1.23 to 1.40; p <0.001) were the strongest predictors of hypertension. Therapeutic intervention included successful lifestyle modification in 57 and required additional pharmacologic treatment in 3 with essential hypertension. Secondary hypertension was treated according to the underlying disorder. After a mean follow-up of 18 ± 6 months, all hypertensive athletes had achieved and maintained optimal control of the blood pressure, without restriction to sport participation. In conclusion, the prevalence of hypertension in athletes is low (3%) and largely related to family history and overweight. In the vast majority of hypertensives, lifestyle modifications were sufficient to achieve an optimal control of blood pressure values.

Upper normal values of blood pressure response to exercise in Olympic athletes

BACKGROUND

Exercise test is widespread performed in athletes to assess cardiovascular adaptations during effort; however, scarce information exists relative to the behavior of blood pressure during exercise in athletes. We sought to define the normal values and upper limits of blood pressure response to exercise in a large population of elite, healthy athletes.

METHODS

A total of 1,876 healthy, normotensive elite athletes (aged 25 ± 6 years, 64% male) underwent a comprehensive clinical evaluation including maximal bicycle exercise test.

RESULTS

At maximum exercise, the systolic blood pressure increased significantly (Δ = +69 ± 18 mm Hg; P< .001), whereas diastolic blood pressure showed minimal change (Δ = +1 ± 7 mm Hg; P= .001). The upper reference values were 220 mm Hg in male and 200 mm Hg in female athletes for systolic blood pressure, and 85 mm Hg in male and 80 mm Hg in female for diastolic blood pressure. A subgroup of 142 athletes (7.5%) showed high blood pressure response to exercise, that is, increase in systolic and/or diastolic blood pressure above the 95th percentile. Multivariate logistic regression analysis showed that endurance and mixed sport disciplines, body mass index, and baseline systolic blood pressure were the strongest determinants for high blood pressure response to exercise.

CONCLUSION

The gender-specific reference values for systolic and diastolic blood pressure at maximum exercise in athletes were defined. A small subset (7.5%) of athletes showed higher blood pressure response, in the absence of target organ disease or metabolic abnormalities, and associated with superior physical performance and larger cardiac remodeling.

Vascular Health in American Football Players: Cardiovascular Risk Increased in Division III Players

Studies report that football players have high blood pressure (BP) and increased cardiovascular risk. There are over 70,000 NCAA football players and 450 Division III schools sponsor football programs, yet limited research exists on vascular health of athletes. This study aimed to compare vascular and cardiovascular health measures between football players and nonathlete controls. Twenty-three athletes and 19 nonathletes participated. Vascular health measures included flow-mediated dilation (FMD) and carotid artery intima-media thickness (IMT). Cardiovascular measures included clinic and 24 hr BP levels, body composition, VO2 max, and fasting glucose/cholesterol levels. Compared to controls, football players had a worse vascular and cardiovascular profile. Football players had thicker carotid artery IMT (0.49 ± 0.06 mm versus 0.46 ± 0.07 mm) and larger brachial artery diameter during FMD (4.3 ± 0.5 mm versus 3.7 ± 0.6 mm), but no difference in percent FMD. Systolic BP was significantly higher in football players at all measurements: resting (128.2 ± 6.4 mmHg versus 122.4 ± 6.8 mmHg), submaximal exercise (150.4 ± 18.8 mmHg versus 137.3 ± 9.5 mmHg), maximal exercise (211.3 ± 25.9 mmHg versus 191.4 ± 19.2 mmHg), and 24-hour BP (124.9 ± 6.3 mmHg versus 109.8 ± 3.7 mmHg). Football players also had higher fasting glucose (91.6 ± 6.5 mg/dL versus 86.6 ± 5.8 mg/dL), lower HDL (36.5 ± 11.2 mg/dL versus 47.1 ± 14.8 mg/dL), and higher body fat percentage (29.2 ± 7.9% versus 23.2 ± 7.0%). Division III collegiate football players remain an understudied population and may be at increased cardiovascular risk.

The toll of the gridiron: damage-associated molecular patterns and hypertension in American football

American football has unequivocally been linked to elevations in blood pressure and hypertension, especially in linemen. However, the mechanisms of this increase cannot be attributed solely to increased body weight and associated cardiometabolic risk factors (e.g.,dyslipidemia or hyperglycemia). Therefore, understanding the etiology of football-associated hypertension is essential for improving the quality of life in this mostly young population, as well as for lowering the potential for chronic disease in the future. We propose that inflammatogenic damage-associated molecular patterns (DAMPs) released into the circulation from football-induced musculoskeletal trauma activate pattern-recognition receptors of the innate immune system-specifically, high mobility group box 1 protein (HMGB1) and mitochondrial (mt)DNA which activate Toll-like receptor (TLR)4 and -9, respectively. Previously, we observed that circulating levels of these 2 DAMPs are increased in hypertension, and activation of TLR4 and -9 causes endothelial dysfunction and hypertension. Therefore, our novel hypothesis is that musculoskeletal injury from repeated hits in football players, particularly in linemen, leads to elevated circulating HMGB1 and mtDNA to activate TLRs on endothelial cells leading to impaired endothelium-dependent vasodilation, increased vascular tone, and hypertension.