Risk Factors For Heart Disease

Heart health is essential to the safety of all divers, symptoms of heart conditions are often subtle or easily missed. In some cases, the first indication of a serious cardiac problem may be a heart attack, or symptoms of an impending attack. The best way that you can protect yourself is to ensure that you understand the primary risk factors of heart disease, regularly consult with your physician, and thoroughly disclose your health histories with instructors and charter operators. These risk factors effect dive professionals’ just as much as new divers, so regardless of your level of experience it’s important that understand them both for your health and safety, and the safety of those you dive with.


Hypertension, or high blood pressure, is a contributing factor in 13 percent of cardiac deaths, and may lead to a thickening and weakening of the tissues in the heart. This change in heart tissue can cause disturbances in heart rhythms, and elevate the risk of stroke, heart attack, and kidney failure. Any of these conditions can be fatal underwater, and while high blood pressure may seem relatively benign, it’s important to recognize that it can result in some very serious consequences if left unaddressed.


While smoking causes a well-known laundry list of cardiopulmonary issues, it is also a leading cause of preventable cardiac diseases. Smoking increases the risk of coronary heart disease, peripheral vascular disease, stroke, SCD and cancer. It also increases blood pressure and lipid levels and can result in sustained, low-level inflammation that causes the cardiovascular system to deteriorate, and may increase your risk of decompression sickness (DCS).


High cholesterol may double a person’s 10-year risk of dying, and increases your risk of clotting conditions, high blood pressure, and stroke. High cholesterol levels rarely give obvious symptoms until they cause a serious cardiac issue, and if these issues occur during a dive, they can cause serious injuries. Lipid levels should be tested regularly by a physician, and can be controlled through diet and medication.


Obesity can be a difficult subject to address, but it significantly elevates a diver’s risk of cardiac problems, among other hazards. Divers who struggle with obesity may need to exert themselves more while diving, which places additional strain on their heart, and may have difficulty dealing with the physical demands of strenuous dives, putting them at an increased risk of injury.

Risk Factors for Heart Disease

BMI is a measure for understanding population trends, but it does have some limitations.

  • It may overestimate the proportion of body fat in athletes and others with a muscular build.
  • It may underestimate the proportion of body fat in older persons and others who have lost muscle mass.

Accordingly, BMI is just one of many factors that should be considered in evaluating whether an individual is at a healthy weight — along with waist size, waist-to-hip ratio and a measurement known as “skin-fold thickness.”


Inactive people are twice as likely to develop heart disease as active people, and while diving is a great way to get out and get exercise, most divers do not get in the water enough to maintain their fitness with diving alone. Regular exercise will minimize your risks of many health-related hazards.

For more information on cardiac risks and diving, read Risk Factors for Cardiovascular Disease, chapter two in DAN’s Heart & Diving Dive Medical Reference Book.

Join DAN