lunes, 30 de enero de 2012

CDC - NIOSH Science Blog – NFL Players Tackling Heart Disease

CDC - NIOSH Science Blog – NFL Players Tackling Heart Disease

NFL Players Tackling Heart Disease

A football player in a green jersey holding a football.Many football players are essentially paid to be big—really big—especially those whose job is to block or stop the big guys on the other team.  There is a good chance that these players weigh in at sizes that are classified as obese as defined by body mass index (BMI).  In the general population, high BMI generally correlates with high body fat, and we know that high body fat is a risk factor for death (mortality) and heart disease.  Is the same true for elite athletes, for whom high BMI may relate to increased muscularity rather than increased body fat?  What if the athlete plays a position where size simply matters, regardless of whether size is related to muscle or to body fat?   And what happens when former athletes are no longer conditioning at their playing-day levels?  Do professional football players die earlier than or more often from heart disease or cancer than the average American male?   New research from the National Institute for Occupational Safety and Health (NIOSH) helps answer these and other questions.
In 1994, NIOSH published research examining death rates and risk factors for former National Football League (NFL) players.1  At that time the research was based on all deaths that had occurred through 1991.   After following these players for an additional 16 years, NIOSH has just published new researchExternal Web Site Icon. on the topic in the American Journal of CardiologyExternal Web Site Icon.
The study included 3,439 retired NFL players from the 1959 through 1988 seasons.  The study found that:
  • Players had a much lower overall rate of death compared to men in the general U.S. population of similar age and racial mix. On average, NFL players are actually living longer than the average American male. Out of the 3,439 players in the study, 334 were deceased. Based on estimates from the general population, we anticipated roughly 625 deaths.
  • Players also had a much lower rate of cancer-related deaths compared to the general U.S. population. A total of 85 players died from cancer when we anticipated 146 cancer-related deaths based on estimates from the general population.
  • Players who had a playing-time BMI of 30 or more had twice the risk of death from heart disease compared to other players. Similar findings have been noted in other studies. Offensive and defensive linemen were more likely to have a BMI greater than 30. A BMI of 30 or more is considered obese in the general population whereas a healthy BMI is between 18.5-24.9.
  • African American players had a 69% higher risk of death from heart disease compared to Caucasian players.   The study controlled for player size and position and determined that those factors are not the reason for this difference.
  • Defensive linemen had a 42% higher risk of death from heart disease compared to men in the general population. A total of 41 defensive linemen died of heart disease, when we anticipated 29 deaths based on estimates from the general population.  Among the 41 defensive linemen who died of heart disease, 8 deaths were due to cardiomyopathy (a specific kind of heart disease that causes the heart to enlarge and can lead to heart failure). We anticipated fewer than two deaths from cardiomyopathy. We saw this increased risk only among the defensive linemen. 

What Does This Mean?

The fact that players live longer than the average American male is likely explained by several factors including previously documented low levels of cigarette smoking which is an important contributor to decreased mortality.2,3  Players’ body composition (more muscle mass) and high fitness levels likely also contribute to their longer life span  compared to the general U.S. population, especially given their increased size. The study did not attempt to contact retired players so we do not have information about whether players smoked or if they have a family history of heart disease, cholesterol, or diabetes. We also lack information on changes in players’ fitness and weight after retirement.
Different access to or compliance with improved medical therapies and prevention methods could be one explanation for the differences in cardiovascular-related deaths between offensive and defensive linemen and deserves further evaluation. Since 2000, cardiovascular disease deaths for defensive linemen, after accounting for differences in size, have been similar to other players.  This may indicate a positive impact from the increased media attention and expanded health promotion campaigns by the NFL and the NFL Players Association since the initial NIOSH report in 1994.2,3
Racial disparities in heart disease risk factors, illness and death are well documented in the general population4 and are partly explained by racial differences in socioeconomic status  (see HHS Office of Minority Health External Web Site Icon.).5 The racial disparity in heart disease deaths in NFL players is notable given players’ more similar socioeconomic status during their playing career and the absence of racial differences in hypertension or prehypertension (indicators of heart disease) in active NFL players. 3
Anabolic androgenic steroid use in athletes has been associated with various adverse cardiovascular outcomes including altered lipid profiles, atherosclerosis, and increased left ventricular dimensions and could contribute to CVD mortality in NFL players.6 A survey of 3,683 retired players found 9% reported anabolic steroid use while playing but offensive and defensive linemen were most likely to report use (16.3% and 14.8%, respectively). Reported usage for all players peaked in the 1980s at 20%.7

What Next?

The study found an association between weight (as expressed in BMI) and risk for heart disease.  Further research is needed to determine whether or to what degree the specific characteristics of a defensive lineman’s playing position, training regimen or post-playing lifestyle might contribute to risk for heart disease.
The decrease in risk for cardiovascular disease deaths for defensive linemen since 2000 would seem to indicate that attention to this issue can reduce risk for death.  We realize that professional athletes are physically unique compared to the general population. When players retire or stop playing due to injury, activity levels may decrease. This lack of activity may result in an increase in percentage of body fat, which places strain on the heart. Though football-related injuries may make it difficult to exercise regularly, it is important that players continue to be active to achieve or maintain a healthy weight. As with the general population, it is also important that players take steps to protect themselves from cardiovascular disease (see CDC guidelines) such as not smoking, eating right and receiving appropriate treatment for medical conditions like high blood pressure and diabetes.
After the 1994 study, the NFL started the NFL Retired Player Cardiovascular Screening Program which provides testing and monitoring for heart health at various locations across the country. Screenings like this as well as regular consultations with their doctors can help players monitor their health and take the necessary step to prevent illness and death.
Sherry Baron, MD, MPH, is the Coordinator for Occupational Health Disparities at NIOSH


  1. Baron S, Rinsky R. Health Hazard Evaluation Report, National Football League Players Mortality Study. Report No. HETA 88-085. Atlanta, GA: Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 1994.
  2. Miller MA, Croft LB, Belanger AR, Romero-Corral A, Somers VK, Roberts AJ, Goldman ME. Prevalence of metabolic syndrome in retired National Football League players. Am J Cardiol 2008;101:1281– 1284.
  3. Tucker AM, Vogel RA, Lincoln AE, Dunn RE, Ahrensfield DC, Allen TW, Castle LW, Heyer RA, Pellman EJ, Strollo PJ Jr, Wilson PW, Yates AP. Prevalence of cardiovascular disease risk factors among National Football League players. JAMA 2009;301:2111–2119.
  4. Mensah GA, Mokdad AH, Ford ES, Greenlund KJ, Croft JB. State of disparities in cardiovascular health in the United States. Circulation 2005;111:1233–1241.
  5. Williams DR, Mohammed SA, Leavell J, Collins C. Race, socioeconomic status, and health: complexities, ongoing challenges, and research opportunities. Ann N Y Acad Sci 2010;1186:69 –101. 
  6. Achar S, Rostamian A, Narayan SM. Cardiac and metabolic effects of anabolic-androgenic steroid abuse on lipids, blood pressure, left ventricular dimensions, and rhythm. Am J Cardiol 2010;106:893–901.
  7. Horn S, Gregory P, Guskiewicz KM. Self-reported anabolic-androgenic steroids use and musculoskeletal injuries: findings from the Center for the Study of Retired Athletes Health Survey of Retired NFL Players. Am J Phys Med Rehabil 2009;88:192–200.

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