Association between traditional cholesterol parameters, lipoprotein particle concentration, novel biomarkers and carotid plaques in retired National Football League players

Cardiovascular disease in retired NFL players: a systematic review

OBJECTIVE

Despite robust research endeavors exploring post-play health implications in former NFL players, the impact of former-player status on long-term cardiovascular health has not yet been elucidated. The purpose of this systematic review is to describe the available research on the cardiovascular health in former NFL players.

METHODS

Relevant studies were included from the PubMed, Scopus, and Embase databases. Studies were evaluated in accordance with PRISMA guidelines. Two independent reviewers conducted the title/abstract screenings and risk of bias determinations. The results of the studies were extracted for inclusion in the review.

RESULTS

Sixteen studies met inclusion criteria. Though evidence was discordant among studies, former NFL players appeared to possess more favorable metabolic profiles and decreased mortality compared to community controls. Of note, 90% of former players were found to be overweight or obese.

CONCLUSION

Though cardiovascular disease is the leading cause of death among former NFL players, they possess comparable metabolic and cardiovascular profiles to community controls. Further research is necessary to ascertain the impact of NFL play on cardiovascular health and develop tailored preventative care strategies for former players.

Effectiveness of red yeast rice on carotid atherosclerosis: A systematic review and meta-analysis

While several studies have demonstrated the preventive and therapeutic effects of red yeast rice (RYR), a traditional Chinese medicine, on carotid atherosclerosis through the reduction of low-density lipoprotein cholesterol (LDL-C) level and other risk factors, the evidence remains inconsistent. This study aimed to further evaluate the effects of RYR in carotid atherosclerosis. Several databases were searched for original trials of RYR for the treatment of carotid atherosclerosis that reported plaque indicators. Carotid plaque area (AREA), carotid plaque score (SCORE), and intima-media thickness (IMT) were set as the primary outcomes, while lipid profile and safety indicators were set as the secondary outcomes. Meta-analyses were performed on the randomized controlled trials (RCTs) using Comprehensive Meta-analysis software. Heterogeneity was evaluated using the I2 index and Q statistic. Subgroup, sensitivity, and dose-effect analyses were conducted. Twenty RCTs with 2217 patients were included. Compared to the control group, AREA (SMD = −0.855, 95%CI: −1.259 to −0.451, p < 0.001), IMT (SMD = −0.588, 95%CI: −0.792 to −0.384, p < 0.001), SCORE (SMD = −0.708, 95%CI: −1.135 to −0.282, p = 0.001), LDL-C (SMD = −0.938, 95%CI: −1.375 to −0.502, p < 0.001), triglyceride (SMD = −0.766, 95%CI: −0.980 to −0.551, p < 0.001), and total cholesterol (SMD = −0.858, 95%CI: −1.254 to −0.462, p < 0.001) were significantly decreased and HDL-C (SMD = 0.389, 95%CI: 0.044–0.733, p = 0.027) was significantly increased following RYR therapy. The indicators for safety were not significant and did not differ between the two groups (p > 0.050). Heterogeneities mainly existed for the treatment time or control group setting. Most results showed no changes in the sensitivity analysis. Dose-effect relationships were observed for all indicators except for TC and HDL-C. We concluded that RYR therapy showed considerable efficacy and an acceptable safety profile for the treatment of carotid atherosclerosis in the Chinese population.

The accelerated aging phenotype: The role of race and social determinants of health on aging

The pursuit to discover the fundamental biology and mechanisms of aging within the context of the physical and social environment is critical to designing interventions to prevent and treat its complex phenotypes. Aging research is critically linked to understanding health disparities because these inequities shape minority aging, which may proceed on a different trajectory than the overall population. Health disparities are characteristically seen in commonly occurring age-associated diseases such as cardiovascular and cerebrovascular disease as well as diabetes mellitus and cancer. The early appearance and increased severity of age-associated disease among African American and low socioeconomic status (SES) individuals suggests that the factors contributing to the emergence of health disparities may also induce a phenotype of 'premature aging' or 'accelerated aging' or 'weathering'. In marginalized and low SES populations with high rates of early onset age-associated disease the interaction of biologic, psychosocial, socioeconomic and environmental factors may result in a phenotype of accelerated aging biologically similar to premature aging syndromes with increased susceptibility to oxidative stress, premature accumulation of oxidative DNA damage, defects in DNA repair and higher levels of biomarkers of oxidative stress and inflammation. Health disparities, therefore, may be the end product of this complex interaction in populations at high risk. This review will examine the factors that drive both health disparities and the accelerated aging phenotype that ultimately contributes to premature mortality.

Influence of anti-TNF therapy and homocysteine level on carotid intima-media thickness in rheumatoid arthritis patients

It is a well-known fact that disruptions in the immune system and systemic inflammation are associated with accelerated atherosclerosis in rheumatoid arthritis (RA) patients. Elevated levels of tumor necrosis factor α (TNF-α), a major pro-inflammatory cytokine, are involved in endothelial cell activation of medium and large arteries, leading to increased endothelial permeability, generation of superoxide anion radical and hydrogen peroxide, and decreased availability of nitric oxide (NO). The present study aims to determine the influence of anti-TNF therapy and homocysteine (Hcy) levels on the carotid intima-media thickness (IMT) in patients with RA. Assessments were performed on 115 patients diagnosed with RA on biological treatment to determine the evolution of IMT and Hcy levels. Carotid ultrasonography was used to assess the IMT, as a fast and easy tool for the prediction of cardiovascular events in patients with RA. The first measurement of IMT was noted as IMT1, followed by a second measurement after 1 year, noted as IMT2. The group of patients was divided into approximately three equal groups, each being treated with a different biological product, respectively, etanercept, adalimumab, and infliximab. In the 3 groups, after 1 year of anti-TNF-α therapy, IMT2 progression was significantly reduced compared to baseline. No significant differences were found among the three groups of treatment. A strong association was observed between IMT1-IMT2 in the etanercept group (P<0.001, r=0.758), in the adalimumab group (P<0.001, r=0.761) and in the infliximab group (P<0.001, r=0.829). The low level of Hcy2 after 12 months of anti-TNF-α therapy was significantly correlated with a decrease in IMT2 (P<0.001) in patients who had a high level of Hcy and IMT >0.9 mm at baseline. The results from the present study showed that biological treatment and the low level of homocysteinemia reduced the cardiovascular risk in RA, regardless of the treatment chosen (infliximab, adalimumab, or etanercept).

Biomarker Discovery in Atherosclerotic Diseases Using Quantitative Nuclear Magnetic Resonance Metabolomics

Despite great progress in the management of atherosclerosis (AS), its subsequent cardiovascular disease (CVD) remains the leading cause of morbidity and mortality. This is probably due to insufficient risk detection using routine lipid testing; thus, there is a need for more effective approaches relying on new biomarkers. Quantitative nuclear magnetic resonance (qNMR) metabolomics is able to phenotype holistic metabolic changes, with a unique advantage in regard to quantifying lipid-protein complexes. The rapidly increasing literature has indicated that qNMR-based lipoprotein particle number, particle size, lipid components, and some molecular metabolites can provide deeper insight into atherogenic diseases and could serve as novel promising determinants. Therefore, this article aims to offer an updated review of the qNMR biomarkers of AS and CVD found in epidemiological studies, with a special emphasis on lipoprotein-related parameters. As more researches are performed, we can envision more qNMR metabolite biomarkers being successfully translated into daily clinical practice to enhance the prevention, detection and intervention of atherosclerotic diseases.

Cardiovascular Health of Retired Field-Based Athletes: A Systematic Review and Meta-analysis

BACKGROUND

Retirement from elite sport participation is associated with decreased physical activity, depression, obesity, and ischemic heart disease. Although engagement in physical activity through sport is recognized as cardioprotective, an estimated one-quarter of deaths in American football players are associated with cardiovascular disease (CVD), predominately in players classified as obese.

PURPOSE

To systematically investigate the cardiovascular health profile of retired field-based athletes.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This review was conducted and reported in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and preregistered with PROSPERO. Four databases (PubMed, CINAHL, Embase, and Web of Science) were systematically searched from inception to October 2018 using MeSH terms and keywords. Inclusion criteria were retired field-based athletes, age >18 years, and at least 1 CVD risk factor according to the European Society of Cardiology and the American Heart Association. Review articles were not included. Control groups were not required for inclusion, but when available, an analysis was included. Eligible articles were extracted using Covidence. Methodological quality was assessed independently by 2 reviewers using the AXIS tool. The accuracy of individual study estimates was analyzed using a random-effects meta-analysis.

RESULTS

This review yielded 13 studies. A total of 4350 male retired field-based athletes from 2 sports (football and soccer; age range, 42.2-66 years) were included. Eight studies compared retired athletes with control groups. Retired athletes had elevated systolic blood pressure in 4 of 6 studies; approximately 50% of studies found greater high-density lipoprotein, approximately 80% found lower triglyceride levels, and all studies found greater low-density lipoprotein for retired athletes compared with controls. The prevalence and severity of coronary artery calcium and carotid artery plaque were similar to controls. Retired linemen had double the prevalence of cardiometabolic syndrome compared with nonlinemen.

CONCLUSION

The overall findings were mixed. Inconsistencies in the reporting of CVD risk factors and methodological biases reduced the study quality. Retired athletes had a comparable CVD risk profile with the general population. Retired athletes with an elevated body mass index had an increased prevalence and severity of risk factors. Significant gaps remain in understanding the long-term cardiovascular effects of elite athleticism.

Lipoprotein particle number and size predict vascular structure and function better than traditional lipids in adolescents and young adults

BACKGROUND

In adults, dyslipidemia is associated with higher carotid thickness and arterial stiffness, predictors of cardiovascular events. In young subjects, lipid concentrations have not been consistently associated with vascular measures.

OBJECTIVE

The objective of the study was to compare nuclear magnetic resonance (NMR) measures of lipoprotein particle number (low-density lipoprotein [LDL] particle, low-density lipoprotein [HDL] particle, very low-density lipoprotein [VLDL] particle) and size (LDL size, HDL size, and VLDL size) to determine if they were associated with vascular measures more strongly than lipid concentrations (LDL cholesterol, HDL cholesterol, and triglyceride [TG]).

METHODS

We evaluated 214 lean (L), 228 obese (O), and 214 diabetic (T2DM) subjects aged 10 to 24 years (33% male and 39% Caucasian). Cardiovascular risk factors, vascular structure, and arterial stiffness were measured. General linear models were constructed including demographics, risk factors, and traditional or NMR lipid parameters. A composite vascular function score was developed as the outcome in receiver operator characteristic scores for determining which lipid parameter was superior in predicting vascular damage.

RESULTS

Risk factors worsened from L to O to T. However, LDL cholesterol was similar in O and T, whereas LDL size differentiated the 3 groups (T > O > L, P ≤ .0001). Models demonstrated the superiority of NMR values, which entered for all but 1 vascular outcome and explained more of the variance than traditional lipid concentrations. Receiver operator characteristic curves demonstrated that NMR values were superior in predicting vascular outcomes. Models stratified by race were similar but cutpoints predicting vascular outcomes differed by race for TG, TG/HDL, and VLDL.

CONCLUSION

Lipoprotein particle number and size are more strongly related to vascular structure and function than traditional lipid values. NMR lipid measures may be a better indicator of risk for target organ damage than traditional lipid measures in adolescents and young adults.

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.

A longitudinal study examining the effects of a season of American football on lipids and lipoproteins

Background

Dyslipidemia is one factor cited for increased risk of cardiovascular disease (CVD) in American football players. However, American football players undergo physical conditioning which is known to influence lipids. This study examined if the physical activity of an American football season is associated with changes in lipids and if a relationship exists between lipids and body composition.

Methods

Fourteen division I freshmen American football players had blood drawn prior to summer training (T1), end of competition (T2), and end of spring training (T3). Samples were analyzed for total cholesterol (TCHL), HDL-C, LDL-C, and triglycerides (TG). Body composition was assessed via dual-x-ray absorptiometry. National Cholesterol Education Program (NCEP) lipid categorization was used to characterize participants. Pearson correlations were computed to determine relationships.

Results

Body mass increased T2 (p = 0.008) as a result of increase in fat mass (p = 0.005) and remained high despite a decrease T3. Lean mass did not differ significantly at any time. No significant time effects were observed for lipids measured. The number of participants presenting with risk factors attributed to dyslipidemia varied. By T3, no participant was categorized as “low” for HDL-C. TCHL was moderately correlated (r = 0.60) with fat mass at T1; whereas a moderate correlation (r = −0.57) was observed between BMI and HDL-C at T2. TG was strongly correlated with fat mass at each time point (T1, r = 0.83; T2, r = 0.94; T3, r = 0.70).

Conclusion

The physical activity associated with a season of football results in little change in blood lipids and CVD risk. Further, TG are strongly related to fat mass. Future research should focus on examining the cause of dyslipidemia in American football players.

Relation between playing position and coronary artery calcium scores in retired National Football League players

Retired National Football League (NFL) linemen have an increased prevalence of risk factors for atherosclerosis and have an increased risk of cardiovascular death compared with nonlinemen and the general population. We evaluated whether playing in lineman position is independently associated with an increased risk of the presence and severity of subclinical atherosclerosis. Players were categorized as linemen if they reported playing on the offensive or defensive line during their careers. Subclinical atherosclerosis was assessed using coronary artery calcium (CAC) scores in 931 retired NFL players (310 linemen, 621 nonlinemen). CAC scores were evaluated for absence of subclinical atherosclerosis (CAC = 0), presence of mild subclinical atherosclerosis (CAC 1 to 100), and moderate to severe subclinical atherosclerosis (CAC ≥100). We performed multivariate logistic regression to determine whether the lineman position is independently associated with the presence and severity of subclinical atherosclerosis. Linemen were noted to have a lesser likelihood of absence of subclinical atherosclerosis (CAC = 0, 33.8% vs 41.7%, p = 0.02), a similar likelihood of mild subclinical atherosclerosis (CAC 1 to 100, 33.2% vs 31.8%, p = 0.7), and a greater likelihood of moderate to severe subclinical atherosclerosis (CAC >100, 32.9% vs 26.4%, p = 0.04) compared with nonlinemen. Adjusting for demographic and metabolic covariates, lineman status remained independently associated with mild subclinical atherosclerosis (CAC 1 to 100, odds ratio [OR] 1.41, 95% confidence interval [CI] 1.05 to 2.2, p = 0.04) and moderate to severe subclinical atherosclerosis (CAC ≥100, OR 1.67, 95% CI 1.05 to 2.2). The association was attenuated after adjustment for race (CAC 1 to 100, OR 1.24, 95% CI 0.82 to 1.8; CAC >100, OR 1.59, 95% CI 1.01 to 2.49). In conclusion, lineman status in retired NFL players is associated with presence and severity of subclinical atherosclerosis, which is partly explained by race.

The correlation between serum lipid profile with carotid intima-media thickness and plaque

Background

It is indicated that non-HDL cholesterol and lipid ratios, including total/HDL cholesterol and LDL/HDL cholesterol ratios, are risk indicators with greater predictive value for coronary atherosclerotic progression or regression compared with conventional lipid profile. However, there have been few reports about the correlation between serum lipid profile with carotid intima-media thickness (IMT) and plaque in Chinese general people.

Methods

We examined 402 subjects without apparent diseases in a cross-sectional study (mean age 50.16 years; 36.07% female). Demographics, anthropometrics, and laboratory data were collected. The presence of carotid plaque and intima-media thickness were evaluated by ultrasonography.

Results

Univariate correlations showed carotid IMT was correlated with LDL-C (r = 0.137, p = 0.009), non-LDL-C levels (r = 0.140, p = 0.008) and LDL-C/HDL-C ratio (r = 0.169, p = 0.001). After adjustment for potential covariates, LDL-C/HDL-C ratio (β = 0.132, p < 0.001) were independent variables that interacted on carotid IMT. Other risk factors including age and systolic blood pressure were independently associated with carotid IMT. LDL-C levels, non-HDL-C levels, TC/HDL-C and LDL-C/HDL-C ratios were significantly higher, but HDL-C levels were significantly lower in subjects with carotid plaque than those without it. The subsequent multiple logistic regression analysis showed that LDL-C (OR; 1.325, 95% CI; 1.046-1.821, p = 0.033) and HDL-C levels (OR; 0.093, 95% CI; 0.038-0.227, p < 0.001) were significantly associated with the presence of carotid plaque after adjustment of age. Furthermore, LDL-C combined with HDL-C levels showed the highest area under the curve (0.788, 95% CI; 0.740–0.837, p < 0.001).

Conclusions

Serum LDL-C/HDL-C ratio represents as an independent index associated with increased carotid IMT and LDL-C combined with HDL-C levels may be useful markers for predicting the presence of carotid plaque in the Chinese general population.

Lipoprotein (a): gene genie

PURPOSE OF REVIEW

Despite being both the longest known and the most prevalent genetic risk marker for atherosclerotic cardiovascular disease (CVD), little progress has been made in agreeing a role for lipoprotein (a) [Lp(a)] in clinical practice and developing therapies with specific Lp(a)-lowering activity. We review barriers to progress, and discuss areas of controversy which are important to future research.

RECENT FINDINGS

Epidemiological and genetic studies have supported a causal role for Lp(a) in accelerated atherosclerosis, independent of other risk factors. Progress continues to be made in the understanding of Lp(a) metabolism, and Lp(a) levels, rather than apolipoprotein (a) isoform size, have been shown to be more closely related to CVD risk. Selective Lp(a) apheresis has offered some evidence that Lp(a)-lowering can improve cardiovascular end-points.

SUMMARY

We have acquired a great deal of knowledge about Lp(a), but this has not yet led to reductions in CVD. This is at least partially due to disagreement over Lp(a) measurement methodologies, its physiological role and the importance of the elevations seen in renal diseases, diabetes mellitus and familial hypercholesterolaemia. Renewed focus is required to bring assays into clinical practice to accompany new classes of therapeutic agents with Lp(a)-lowering effects.

Laboratory validation of a low density lipoprotein apolipoprotein-B assay

OBJECTIVES

Numerous publications have shown strong association between CHD risk and either apolipoprotein B (Apo-B) or low density lipoprotein (LDL) particle number (LDL-P). It is however unknown if Apo-B or LDL-P has a stronger predictive ability for future CHD. This uncertainty may be due to the inability of current Apo-B assays to separate the contribution of very low-density lipoprotein particles from the total Apo-B concentration. As such we have performed a laboratory validation of the Maine Standards LDL Apo-B assay on the Roche Cobas 6000 analyzer.

DESIGN AND METHODS

Imprecision, linear range, and limit of quantitation studies were performed using quality control materials. Plasma samples collected for lipid profile analysis were analyzed via the LDL Apo-B assay and compared to the LDL cholesterol (LDL-C) concentration determined via direct LDL assay and Friedewald equation.

RESULTS

The LDL Apo-B within-run imprecision was 2.3% at 62 mg/dL and 2.2% at 109 mg/dL. The within-laboratory imprecision was 9.7% at 57 mg/dl and 6.1% at 104 mg/dL. Linear regression analysis of LDL Apo-B versus calculated and measured LDL-c resulted in equations of LDL Apo-B=0.620∗(LDL)+45.4, R=0.9063 and LDL-Apo-B=0.607∗(LDL)+38.8, R=0.9393, respectively. Bias plot analyses revealed that at low LDL-C concentration, there was a tendency for a higher than anticipated LDL Apo-B concentration.

CONCLUSIONS

The Maine Standards LDL Apo-B assay is a precise automated assay and comparison of LDL Apo-B to LDL-c concentration demonstrates that low LDL-C concentrations may still carry residual risk of CHD due to increased concentration of small dense LDL particles.

Neck circumference is not associated with subclinical atherosclerosis in retired National Football League players

BACKGROUND

Neck circumference (NC) is associated with metabolic syndrome (MetS) in the general population. It is not known if NC is associated with MetS and subclinical atherosclerosis in retired National Football League (NFL) players.

HYPOTHESIS

We hypothesized that NC is associated with MetS and subclinical atherosclerosis (assessed as coronary artery calcium [CAC] and carotid artery plaque [CAP]) in retired NFL players.

METHODS

NC was measured midway between the midcervical spine and midanterior neck in 845 retired NFL players. CAC presence was defined as total CAC score >0. CAP was defined as carotid plaque of at least 50% greater than that of the surrounding vessel wall, with a minimal thickness of at least 1.2 mm on carotid ultrasound. Logistic regression analysis was used for the association of NC with CAC or CAP.

RESULTS

Of the participants, 21% had MetS. CAC and CAP were present in 62% and 56%, respectively. Those with MetS had a higher median NC than those without MetS (17 vs 16 inches, P < 0.0001). NC was not associated with the presence of CAC or CAP in an unadjusted model and after adjusting for age, race, and cardiometabolic risk factors (odds ratio [OR]: 1.11, 95% confidence interval [CI]: 0.94-1.31 for CAC; OR: 0.96, 95% CI: 0.82-1.12 for CAP per 1-standard deviation increase in NC [3.8 inches]). The results were similar when the predictor variable was NC indexed to body mass index.

CONCLUSIONS

In retired NFL players with a high prevalence of CAC and CAP, NC was not associated with coronary or carotid subclinical atherosclerosis. NC may not be the most appropriate risk marker for atherosclerosis.