America’s 10 Deadliest Diseases

April 15, 2016 by Sam Stebbins

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Not including accidental deaths and suicide, the 10 most common causes of death in the United States are diseases. Heart disease and cancer, the two leading causes of death overall in the United States, account for nearly half of the deaths recorded annually — nearly 1.2 million deaths.

To determine the deadliest diseases in the country, 24/7 Wall St. reviewed mortality data from the Centers for Disease Control and Prevention. The deadliest diseases in the United States range from heart disease, which caused 611,105 deaths in 2013, to liver disease, which directly resulted in 36,427 deaths.

Heart disease is by far the most common cause of death in the United States. In an interview with 24/7 Wall St., Dr. Baxter Allen, Chief Resident in Neurology at Weill Cornell Medicine, New York Presbyterian Hospital, explained why heart disease is such a common killer. While people who develop other diseases can often live with the disease for years, this is less so the case with heart disease. “There’s only one heart, and if it stops working, then you’re dead,” Allen said. Additionally, the United States is currently in the midst of an obesity epidemic and “obesity is a major risk factor for diabetes, liver disease, and heart disease.”

Click here to see America’s 10 deadliest diseases.

Cancer is the second leading cause of death in the United States. Since President Richard Nixon declared war on cancer in 1971, enormous investments have been made in cancer research. The National Cancer Institute alone has spent roughly $4.9 billion on cancer research each year since 2005. Yet, a cure has eluded researchers. According to Allen, age is the greatest risk factor associated with cancer, and “as the population ages, which it is significantly with the baby boomer generation starting to hit their 70s, [cancer cases] are likely to increase dramatically.” According to a report by the American Society of Clinical Oncology, cancer will become the leading cause of death in the United States by 2030.

Many of the most common deadly diseases in the country tend to afflict Americans who share similarly unhealthy behaviors. For example, the connection between smoking and certain types of cancer, heart disease, chronic respiratory illness, and stroke is well established. Alcohol abuse also increases the risk of certain cancers as well as liver disease and cirrhosis. Unhealthy behaviors such as these, Allen said, “are all independent risk factors for decreased life expectancy.”

Even diseases that are commonly understood to be genetically predetermined can have additional behavioral risk factors. Experts believe that roughly one third of Alzheimer’s cases may be preventable through the modification of risk factors such as high blood pressure, physical inactivity, and others.

Many of the deadliest diseases are interconnected, and the occurrence of one can increase the likelihood of another in an individual. For instance, kidney disease, one of the leading causes of death, can be caused by both liver failure and heart disease, themselves among the leading causes of death.

For this reason, the deadliness of certain diseases may be underrepresented by the numbers. According to the CDC’s report, diabetes is the seventh leading cause of death, directly responsible for 75,578 deaths in 2013. According to the American Diabetes Association, it is actually relatively rare for diabetes to be recorded as the direct cause of death on the death certificates of diabetics, suggesting diabetes could be underreported as the cause of death.

“The health industry is trying lots of things to address these killers,” Allen said. While the incidence of cancer, for example, may increase with the aging of the population, constantly improving treatments — the result of ongoing cancer research — may continue to improve death rates in the near future. On the other hand, Allen said, “Without a significant breakthrough, Alzheimer’s disease is going to account for an increasingly large proportion of death as it is estimated to triple in number of affected people by 2050.”

In order to determine the deadliest diseases in the United States, 24/7 Wall St. reviewed the total number of deaths attributable to a given disease in 2013 from the Centers for Disease Control and Prevention’s (CDC) annual National Vital Statistics Report, Deaths: Final Data for 2013. Historical death rates per 100,000 from 1999 are age adjusted and also came from the CDC. The report was published on February 16, 2016 and contains figures for the recent period for which data is available.

These are the 10 deadliest diseases in the United States.

10. Chronic liver disease and cirrhosis
> Total Deaths in 2013:
36,427

As is the case with many of the diseases killing the most Americans, liver disease and cirrhosis are often attributable to unhealthy behavior. The most common causes of liver disease are hepatitis B and C and alcohol abuse. However, the mortality rate for chronic liver disease and cirrhosis is on the rise while the incidence of alcohol abuse and hepatitis has remained relatively stable. Meanwhile, nonalcoholic fatty liver disease (NAFLD), a condition with no known cause, has seen a two-fold increase, likely contributing most to the rise in mortality from chronic liver disease.

9. Septicemia
> Total Deaths in 2013:
38,156

The septicemia mortality rate increased from 11.0 deaths per 100,000 people in 1999 to 12.1 deaths per 100,000 people in 2013. Septicemia, also known as sepsis, is a serious response of the body’s immune system to an infection. While infection of any kind can lead to sepsis, according to Allen, most are commonly caused by bacteria or fungal infection getting into the bloodstream from an underlying pneumonia, urinary tract infection, gut infection, or skin wound. Septicemia can also occur due to an infection caused by a surgical procedure. An estimated 10% of all hospital patients develop sepsis, and one in 10 of those patients die.

8. Chronic kidney disease
> Total Deaths in 2013:
47,112

The most common causes of renal failure, according to Allen, are chronic diabetes and high blood pressure. While the prevalence of high blood pressure in adults has decreased substantially from roughly 20% to 12% between 1999 and 2010, chronic kidney diseases have become more common. The death rate from nephritis — inflammation of the kidneys — increased from 12.7 to 14.9 deaths per 100,000 people over the period of 1999 through 2013. The increase is likely attributable to growing diabetes rates. As is the case with several other deadly diseases, Allen explained, the incidence of chronic kidney disease could be considerably reduced with lower smoking rates.

7. Influenza and pneumonia
> Total Deaths in 2013:
56,979

Flu and pneumonia are the most common infectious causes of death in America. The illnesses claimed a combined 56,979 lives in the United States in 2013. The mortality rate attributed to these diseases has decreased significantly over the past 15 years, from 22.8 to 18 deaths per 100,000 people. Certain forms of both pneumonia and influenza can be prevented with proper vaccination. Worldwide, vaccinations overall save roughly 6 million people per year, according to the World Health Organization. Many lives are saved due to the prevention of the flu and various infectious pnuemonias.

6. Diabetes mellitus
> Total Deaths in 2013:
75,578

Diabetes directly caused 75,578 deaths in 2013, the sixth highest death toll from a single disease in the United States. Further, diabetes is likely far more deadly than the numbers suggest. Only 10% of deaths of those with diabetes have the disease recorded on their death certificates. Diabetes is also a significant risk factor for stroke, heart disease, kidney disease, infection, and other diseases. The death rate attributed to diabetes has remained mostly stable over the 15-year reporting period from 1999 through 2013, decreasing slightly from 24.5 to 23.9 deaths per 100,000 people.

5. Alzheimer’s Disease
> Total Deaths in 2013:
84,767

The nearly 85,000 lives claimed by Alzheimer’s disease in 2013 is only part of the story. There are over 5 million Americans currently living with the disease. Not only does Alzheimer’s ruin lives and disrupt families, but also it takes a significant economic toll. The Alzheimer’s Association projects that the disease and other forms of dementia will cost the U.S. economy $236 billion in 2016 alone. As is the case with many of the deadliest diseases, Alzheimer’s is not entirely genetically predetermined. Based on evidence published in Lancet Neurology in 2014, approximately one-third of Alzheimer’s cases can be attributed to potentially avoidable risk factors such as high blood pressure, diabetes, and physical inactivity.

4. Stroke
> Total Deaths in 2013:
128,978

As is the case with many of the deadliest diseases in the country, the incidence of death attributable to stroke is decreasing. Over a decade and a half, the death rate from stroke has declined from 60.0 deaths per 100,000 people in 1999 to 40.8 deaths per 100,000 people in 2013. As with the associated decrease in deaths from heart disease, much of this can be attributed to declining smoking rates and improvement in the treatment of high blood pressure and cholesterol.

3. Chronic lung diseases
> Total Deaths in 2013:
149,205

While cancer and heart disease death rates have decreased since 1999, the incidence of death attributable to chronic lung diseases has increased over the same time period. There were roughly 47.2 deaths for every 100,000 people due to chronic lung diseases in 2013, slightly more than the 44.5 deaths for every 100,000 people in 1999. The main contributors to this category of disease are emphysema and other chronic lower respiratory diseases. Smoking and secondhand smoke exposure, air pollution, toxin exposure, and obesity are all significant risks for chronic lung disease.

2. Cancer
> Total Deaths in 2013:
584,881

Cancer was the underlying cause of more than half a million deaths in 2013 — despite improving treatment and earlier detection methods. Such improvements certainly helped lower the incidence of cancer death during the last 15 years, from 197 to 185 deaths per 100,000 people. However, as the U.S. population ages, the total number of new cancer cases is expected to increase as age is the most important risk factor associated with cancer. According to the American Society of Clinical Oncology, cancer will overtake heart disease as the leading cause of death in the United States by 2030. While aging is unavoidable, there are multiple modifiable risk factors that can lower the risk of cancer; not smoking, minimal alcohol consumption, a healthy diet low in red and smoked meats, and avoiding radiation from the sun.

1. Heart disease
> Total Deaths in 2013:
611,105

The death rate from heart disease has decreased from 259.9 to 193.3 deaths per 100,000 people over the last decade and a half. This decline is likely due to lower smoking rates and improved medications for some modifiable risk factors such as high cholesterol and blood pressure, Allen explained. Despite recent improvements, heart disease is the leading cause of death in the United States. Diet is also a major factor. According to the CDC, 90% of Americans consume more sodium than is recommended. Excess sodium consumption can increase the risk of high blood pressure, which can in turn lead to heart disease and stroke. Cardiovascular diseases and stroke cost the nation an estimated $273 billion annually.