Firefighter Obesity: A Public Safety Risk
|Tuesday, 03 May 2011|
By Kevin Spratlin
Reprinted with permission of Fire Engineering
Firefighters are at a significant risk of suffering fatal cardiovascular events related to the performance of their duties. Sudden cardiac death has consistently been the number-one cause of firefighter line-of-duty deaths (LODDs) each year in the United States.1
Firefighters are frequently called to provide aid to the communities they serve, whether it be to extinguish fires, mitigate hazardous materials scenes, perform rescues, or - increasingly more common - provide emergency medical care in the pre-hospital setting. Unhealthy firefighters, particularly those who are overweight and obese, potentially place the public’s safety in jeopardy if they are unable to successfully perform their physically rigorous jobs or are suddenly incapacitated because of an acute coronary event.
If fire departments are to continue their lifesaving mission, it is of critical importance that fire service leaders implement wellness and fitness initiatives within their departments to encourage firefighters to practice healthful living habits. They should include maintaining proper body weight and body mass index (BMI) values; keeping blood pressure, blood cholesterol, and blood glucose at normal levels; and undergoing periodic medical examinations for early recognition of underlying cardiovascular disease (CVD) risk factors.
Causes of Fatalities
The United States Fire Administration (USFA) reports that medical etiologies, particularly those which are cardiac in nature, are the leading cause of death in firefighters over age 35, whereas trauma is the leading cause of death for those under age 35.2 Statistics compiled by the National Fire Protection Association (NFPA) show that there were 1,148,850 firefighters, both career and volunteer, in the United States in 2008. (1)
My review of U.S. firefighting agencies also found that “departments protecting larger communities tend to have a higher proportion of firefighters in the age groups 30-39 and 40-49 than small communities.”3 This is the case within the Memphis (TN) Fire Department (MFD), which has approximately 1,850 sworn personnel and civilians. During a jobwide Firefighter Wellness class in 2009, firefighters were surveyed with an anonymous questionnaire. Of the 1,192 personnel who voluntarily responded, all but 160 (13 percent) reported that they were over the age of 30.4
Cardiovascular Disease and Fatalities
The line-of-duty deaths associated with cardiovascular disease often occurred following strenuous duties on emergency scenes. Some of the “biological-plausible explanations” given for these events included “the effects of heavy protective equipment, irregular physical exertion, gaseous and particulate smoke exposures, and physiological stressors on patients with underlying coronary heart disease (CHD).”5
Many of these fatal events could have been avoided through improved physical fitness, better nutrition regimens, and periodic medical monitoring of personnel by fire departments throughout the firefighters’ careers.6 However, because of the nature of their jobs, many firefighters spend considerable amounts of on-duty time waiting for emergencies to occur; many are sedentary instead of taking part in physical fitness activities. These periods of rest and light work around the station are often “punctuated by unpredictable and stressful bursts of high-intensity and potentially life-threatening activities,” which place significant stress on the cardiovascular system.7 In fact, heart rates often begin to race at the very beginning of the call, when firefighters are dispatched, as a result of an activation of the sympathetic nervous system and continue throughout the remainder of the call because of increased exertion.8
Other emergency responders, including police officers and emergency medical services (EMS) personnel, operate under similar adverse conditions, such as those that require physical exertion on dangerous emergency scenes, undergo similar preemployment screening such as physical agility tests, and are subjected to similar psychological stressors. Despite these similarities, the rate of deaths attributed to adverse cardiac events is disproportionally higher in firefighters. Specifically, cardiac events are responsible for 22 percent of the on-duty deaths of law enforcement officers and only 11 percent of emergency medical technicians and paramedics.9 Also, firefighters die of work-related cardiac events at a greater rate than members of other physically demanding professions such as construction.10
The NFPA points out that some 50 percent of the on-duty firefighters who die of cardiac events had preexisting cardiovascular disease.11 The prevalence of this potentially life-threatening medical condition in firefighters reflects that of the general population and is a significant contributor to morbidity and mortality among firefighters. There is a strong association between underlying risk factors and preexisting heart disease and on-duty firefighter coronary heart disease fatalities. (6, 1757)
Obesity Predisposed to CVD
One prominent CVD risk factor among firefighters is obesity, considered to be of “epidemic” proportions in the general population of the United States. In 2000, most U.S. adults - approximately 56.4 percent (65.5 percent of men and 47.6 of women) - were overweight, an increase of 61 percent since 1991.12 Another study found that one in two adults in the United States is overweight or obese.13 A decade later, yet another study found that obesity among U.S. adults had increased nearly 50 percent during the 1980s and 1990s and that the percentage of adults in the overweight and obese categories had reached nearly 70 percent of the nation’s population, which the authors said made obesity “a critical problem in the United States.”14
Each year, 300,000 U.S. adults die of obesity-related diagnoses. (12, 1195) Even more startling than the growth in obesity is the fact that “the distribution of BMI in the United States has shifted in a skewed fashion such that the proportion of the population with morbid obesity has increased by a greater extent than overweight and mild obesity.” (14, 1925)
…[T]he prevalence of a BMI (self-reported) of 40 or greater (about 100 lbs. overweight) quadrupled from about 1 in 200 adult Americans to 1 in 50; the prevalence of a BMI of 50 or greater increased by a factor of 5, from about 1 in 2000 to 1 in 400. In contrast, obesity based on a BMI roughly doubled during the same period, from about 1 in 10 to 1 in 5.15
There is a strong correlation between obesity and hypertension. One study suggests: “Control of overweight would eliminate 48 percent of hypertension in whites and 28 percent in blacks.”16 This same study further pointed out that “for each decline of 1 mm Hg in diastolic blood pressure, the risk of myocardial infarction decreases an estimated 2-3 percent.” This greater risk of suffering a cardiac event is caused by a thickening of the heart’s ventricular wall and a resultant larger heart volume. These conditions are more prevalent in patients who are both overweight and hypertensive. (16, 2586)
Multiple other adverse health consequences are considered to be secondary to obesity. Among them are gallbladder diseases, respiratory dysfunction such as obstructive sleep apnea, and certain forms of cancerous pathologies.17 A higher incidence of osteoarthritis has also been identified among the overweight and obese.18 The risk of developing diabetes, gallstones, hypertension, heart disease, and stroke increased in proportion to the degree of overweight among both women and men, who were compared to same-sex peers with BMIs reflecting normal weight.19
As measured by the National Heart, Lung, and Blood Institute (www.nhlbisupport.com/bmi/bminojs.htm), adults are considered overweight when the BMI is between 25 and 29.9 and obese when it is 30 or greater. This site has a calculator that computes your BMI. You simply put in your height and weight in the spaces designated, and your BMI is immediately computed.
There are some limitations when using BMI as a value for determining normal vs. abnormal body size. For example, body proportions (relative leg length or relative sitting height) affect BMI: Individuals with shorter legs can have BMI values higher by as much as five units.20 Also, BMI fails to distinguish between excess body weight caused by body fat and that caused by bone and muscle mass; it does not define fat distribution, which is another important consideration in obesity-related risk factors.21
Obesity Among Firefighters
The incidence of obesity among firefighters often surpasses that of the general population.
A two-year study of a small group of MFD firefighters found an alarmingly high rate of weight gain among young firefighters. Nineteen members of fire recruit class #90, which was hired and began basic firemanship and emergency medical training in October 2008, were weighed and had BMI values calculated during their training at the Memphis Fire Training Academy and periodically over the two years since their induction into the fire service. These 19 firefighters were below the threshold age of 45 identified in the study by Soteriades et al., since the City of Memphis requires that fire recruits be between the ages of 21 and 35 on their date of hire. (5) On average, these 19 firefighters gained 11.1 pounds and saw BMI values increase by 2.4 over the two-year period.25 Of this group, three lost a few pounds, and the remaining 16 gained - some considerably - including three who gained more than 30 pounds each.
Since obesity is considered a major CVD risk factor, many overweight and obese firefighters are predisposed to a higher incidence of adverse cardiac events than their normal-weight peers. In a study of 332 Massachusetts firefighters, Soteriades et al. found that obese firefighters were more likely to have medical histories of hypertension and low levels of so-called “good cholesterol,” whereas those firefighters classified as extremely obese “had an average of 2.1 CVD risk factors (excluding obesity) in contrast to 1.5 CVD risk factors for normal-weight firefighters.” (6, 1756)
CVD risk factors in addition to obesity are commonly considered to be hypertension, defined as resting blood pressure greater than or equal to 140/90 millimeters of mercury (mm Hg) and a previous diagnosis of hypertension or treatment with prescribed antihypertensive medications; current cigarette smoking or smoking within the previous 12-month period; high blood cholesterol, a previous diagnosis of high blood cholesterol, or treatment with lipid-lowering pharmacotherapy; and diabetes mellitus, previous diagnosis of diabetes or treatment with insulin or other hypoglycemic medications. (5)
Job Performance and Weight
As determined by researchers at Auburn University’s Human Performance Laboratory, excess body weight adversely affects firefighters’ abilities to perform their duties. A study of Montgomery, Alabama, firefighters found that “... added weight and body fat affected performance of firefighters on the fireground ... there was a direct relationship between added body weight and decreased physical performance. Additionally, as body weight increased, efficiency decreased and fatigue set in faster.”26
Firefighters unable to fulfill their duties because of poor physical conditioning, such as obesity, place not just themselves at risk but also their fellow emergency responders. “A firefighter at less than optimal health can affect crew safety by various means, including a rapid rate of air consumption or the inability to move/carry hose or climb.”27 The respiratory function of obese firefighters is impaired by “a decrease in residual lung volume associated with increased abdominal pressure on the diaphragm,” particularly when fat is distributed through the visceral area, as is found commonly in men. (16) These overweight firefighters, who are often breathing at a faster rate than their fit peers, especially during rigorous activity, are often forced to exit toxic environments much more quickly because of their need to change air bottles on their self-contained breathing apparatus (SCBA). This limits their ability to perform their duties in a time-efficient manner.
Public safety may be jeopardized because of firefighters who are not healthy enough to function on emergency scenes that necessitate significant physical exertion. (6, 1756) Better physical conditioning among firefighters will lead to safer emergency scenes: “Individuals with greater physical capacity are better prepared to deal with adverse firefighting conditions such as aerobically challenging physical labor, physical and chemical exposures, and often unpredictable work hours.” (22)
Overweight firefighters are also at a higher risk of suffering illness and injuries secondary to heat stress, especially when you consider the physiological demands associated with wearing approximately 50 pounds of structural firefighting thermal protective clothing and SCBA in elevated ambient temperature environments. These firefighters are often working at physically exertional tasks such as crawling through hot, smoky environments or advancing hoselines to the seat of fires, resulting in an increased risk of personnel suffering heat disorders. (6, 1757)
The protective clothing worn by firefighters, often called turnout gear, is designed to protect them from the toxic environment and short-term flame contact found on fire scenes. Unfortunately, it may also have the unavoidable side effect of causing firefighters to develop elevated core body temperatures and resultant increased cardiovascular strain as the heart rate increases secondary to exertion.28 This taxing of the cardiopulmonary system occurs as a result of the body’s attempt to cool itself by pumping additional blood to the skin’s surface to promote heat exchange outward to the environment. The turnout gear often serves to inhibit the body’s intrinsic thermoregulatory mechanism by limiting water vapor permeability, which would aid in cooling the body.29
Heat disorders that may occur include heat cramps, heat stress, or - worst of all - heat stroke, considered a life-threatening emergency. A firefighter who experiences any degree of heat stress needs to be removed from active fire suppression activities to formal rehabilitation, including rehydration by oral or intravenous means and medical evaluation. The stricken firefighter should be transported by ambulance for physician evaluation if warranted.
A U.S. military study has shown a correlation between obesity and heat stress, confirming the increased incidence of exertional heat illnesses among overweight Marine Corps recruits involved in physical activities such as running. (30) While evaluating recruits involved in training exercises at the U.S. Marine Corps Recruit Depot at Parris Island, South Carolina, researchers determined that recruits with BMI values at or above 22 kg/m2 were at an eightfold risk of experiencing exertional heat illnesses as compared to fellow recruits with BMI values less than 22 kg/m2. Furthermore, “only one-fifth (18 percent) of male recruits met these criteria for high risk, but they accounted for nearly half (47 percent) of the exertional heat illness cases occurring during the 12-week basic training course.” (30)
The Economic Costs of Obesity
Significant increased economic costs are associated with obesity. Researchers from the federal Centers for Disease Control and Prevention calculate that the cost of obesity-related treatments in the United States is as much as $147 billion per year, or 9.1 percent of all annual medical costs. Also, based on the 2006 study, obese persons spent 42 percent more for medical care than persons of normal weight.31
Reducing the incidence of obesity among firefighters by improving their physical condition could result in substantial cost savings for fire departments that implement wellness initiatives for their personnel. A two-year study by the University of the Pacific in Stockton, California, involving 39 firefighters resulted in one department’s saving $68,741, attributed to a reduction in absenteeism secondary to on-the-job injuries. As part of the study, the firefighters participated in physical activities including “a 5-10 minute warm-up, a minimum of 20 minutes of cardiovascular exercise, strength training, and stretching.”32 Lost time from duty-related injuries dropped by a staggering 447 percent following the implementation of the wellness program, which translated into a decreased amount of absenteeism and lower workers’ compensation premiums.
One of the most important steps toward improved firefighter health and lowered obesity rates is the implementation of comprehensive wellness and fitness initiatives. These programs should include periodic medical screenings for early detection of CVD risk factors; required on-duty physical fitness programs; and, most importantly, a strong commitment from management and labor to develop a healthier and fitter firefighting force.
It is also imperative for fire service leaders to mandate formal rehabilitation on the fireground and other emergency scenes to allow firefighters to recuperate from the significant physiological strains placed on them during emergency operations, which necessitate significant exertion such as during fire suppression activities. A designated safety officer, empowered by the incident commander, should be on scene during major operations to keep the firefighters’ best interests at heart and remove cardiovascular-compromised personnel from active operations.33
The increasing incidence of unfit, overweight firefighters places the public’s safety at risk when these firefighters are unable to perform at optimal levels during stressful emergency situations. Embracing wellness and fitness programs as well as formal on-scene rehabilitation will help keep firefighters healthier, allowing them to more fully accomplish the fire service’s primary missions of life safety, incident stabilization, and property conservation.
Kevin Spratlin, BPS, NREMT-P, is a firefighter/paramedic and training instructor with the Memphis (TN) Fire Department. He has been a member of the fire service since 1992 and involved in EMS since 1995.
Kevin Spratlin, “Firefighter Obesity: A Public Safety Risk,” Fire Engineering, Vol. 164, No. 1, January 1, 2011, pp. 20-28.