IAFC 150 anniversary logo

The Number-One Killer of Firefighters: Cardiovascular Disease

 Do you have an annual physical? What if we told you that you’re probably already being tested to determine if you have a high risk for developing significant cardiovascular disease? What is your health care provider doing with the information?

Firefighters = Elevated Stress Hormone Levels

It’s the job—almost every aspect of our jobs teaches us to respond chemically to perform physically: fight or flight hormones. Fortunately, those hormones do make us perform better, faster, stronger.

But there’s a downside. Those hormones also are catabolic—they break us down—and they adversely affect the insulin, “master metabolic hormone.”

Stress hormones appear to affect insulin! You lack energy. It’s getting harder to exercise, and when you do, you’re not recovering. You’ve been sick more and you’re getting fat around the middle.

Insulin resistance (IR) and the problems associated with it represent the single most important public health problem we face. About 30% of all Americans have insulin resistance. This silent killer is related to lipid (fat) metabolism disorders.

In almost all cases, without lifestyle modification and medical treatment, IR will develop into type-2 diabetes mellitus, heart disease or hypertension, which may predispose you to stroke and other very serious problems.

What Is Insulin?

Insulin is a hormone made and released by beta cells of the pancreas, with many functions related to your metabolism. When you eat food, especially carbs, your blood sugar level increases. A normally functioning pancreas releases insulin in response to higher sugar levels in your blood.

Insulin is your cells’ gatekeeper; it allows sugar to enter the cell, and without it, glucose can’t enter cells to be used as fuel. Your body, particularly the brain, prefers glucose for fuel, but excess amounts of sugar and insulin over time, as in IR, can severely disrupt the body’s machinery.

When insulin levels are low, fat as free fatty acids (FFA) leaves fat cells to be used as fuel; when insulin levels are high, fat is stored. When these cells become insulin resistant, the pancreas releases more insulin to keep sugar levels in a normal range.

In the face of excess insulin, the insulin-resistant cells begin to leak FFAs, so FFA levels go up. In a normal situation, without IR, fat is deposited when insulin is secreted and FFA levels remain low.

What Is Insulin Resistance?

Insulin resistance occurs when your body’s insulin can’t overcome the resistance of the target cells and properly lower your blood sugar levels. The result is that blood sugar and blood insulin levels rise.

The following are risk factors for developing insulin resistance:

  • Weight gain or being overweight
  • Lack of exercise/sedentary lifestyle
  • Genetics
  • Smoking
  • Possible high catecholamine levels (adrenal stress)

Insulin resistance can be found in many other conditions beyond diabetes mellitus, including

  • Cardiovascular disease
  • Stroke
  • Hypertension
  • Non-alcoholic fatty liver disease
  • Obesity
  • Polycystic ovary syndrome
  • Asthma
  • Some cancers, especially breast, ovarian and prostate
  • Alzheimer’s disease

The many diseases that coexist and have a relationship with IR have led it to be called the common thread for most diseases of modern civilization. The bad news is that IR is increasingly common and serious and can lead to many diseases; the good news is that IR and its related problems are preventable!

The key to preventing IR is early diagnosis and effective intervention. We can treat insulin resistance; we can even reverse it in many cases, unlike diabetes, which often results in many difficult and challenging complications, even with the best treatment.

It can take as long as 15-20 years for IR to develop into type-2 diabetes. This gives us a great opportunity to implement healthy lifestyle changes and intervene to stop and even reverse IR.

How Do Lipids Relate to Insulin Resistance?

In a research paper on IR, “Is There a Simple Way to Identify Insulin Resistant Patients at Risk of Developing Cardiovascular Disease?” some of the world’s foremost experts on metabolic disorders explain key points about lipids and their relationship to IR. To simplify,

  • In a patient’s lab results and traditional cholesterol testing, a high triglycerides and low HDL (good cholesterol) number suggests IR.
  • Calculating the ratio of triglycerides/HDL is a simple way to measure how effectively a patient can use glucose; that is, is the insulin being produced working? This is important: we don’t need expensive tests to tell us how your insulin is working!
  • A triglycerides/HDL ratio = 3.5 means IR; the higher the ratio, the more severe the resistance!
  • Triglycerides/HDL ratios also indicate who’s at increased risk for cardiovascular disease. In the fire service, the leading killer of both men and women is heart disease. Your lipid numbers can tell us about your metabolic state and if you’re at increased risk for heart disease!

So there is a simple way to identify IR patients at risk of developing cardiovascular disease. Take advantage of this. Pull your lab work. Do the math. If your ratio is greater than 3.5, you need to see a healthcare professional who understands these issues.

How Is Insulin Resistance Treated?

We believe there are four key considerations for the treatment of IR:

  • Cut the carbs – Eliminating sugar and other carbs like potatoes, beer, pasta and high fructose corn syrup from your diet is an effective lifestyle modification. A high-carb, low-fat diet is about the worst thing you can do. Find a registered dietician who knows about IR and its impact on your body.
  • Get an exercise program, particularly one that involves resistance training – Exercise raises HDL and promotes insulin sensitivity in muscle, increasing you body’s ability to respond to insulin and reduce blood sugar levels. Consult with an exercise physiologist.
  • Lose weight – Even a 5% weight loss can make a significant impact on your metabolic state. For patients with IR, losing belly fat is of great concern and focus. Excess fat around the belly can act like an independent endocrine organ! 
  • Consider your medications – Some say medications like Metformin and other oral anti-diabetic medications can promote insulin sensitivity and fight the progression of IR and the development of type-2 diabetes. Experts debate this off-label use; you need to consult your physician.

As a nation, we face an obesity and a diabetes epidemic. We’re gaining a better understanding of the basic mechanisms involved in both of these serious conditions and can now offer better treatments. It’s more important than ever that we identify and treat IR early before it becomes type-2 diabetes.

Tamara Lopes is the safety and training division chief with the Reno Fire Department, a principle member on NFPA 1500 Committee for Fire Service Safety and Health and a program director for elite athlete training programs. She’s a member of the SHS Section and a member of the IAFC Medical Evaluation Task Force.

Related News
You are not logged in.