Type 2 Diabetes in the U.S.: Causes, Costs & Prevention

Introduction to Type 2 Diabetes

Type 2 Diabetes (T2D) was previously known as non-insulin-dependent diabetes. Unlike an individual with Type 1 diabetes, a person with T2D continues to produce insulin, but the body fails to respond to it in a normal manner. Glucose cannot penetrate the cells and supply the required energy—a condition commonly referred to as insulin resistance. Eventually, blood sugar levels rise and cause the pancreas to produce additional insulin. Over time, the pancreas wears out from overworking to generate surplus insulin and becomes unable to produce adequate amounts to keep blood sugar levels normal. Individuals with insulin resistance may or may not develop T2D (Atta-ur-Rahman, Reitz & Choudhary, 2010). This outcome is independent of the pancreas's ability to generate enough insulin to keep blood sugar within normal ranges. In most cases, elevated blood sugar levels are directly related to diabetes.

Children and teens with T2D often rely on exercise, diet, and medications to enhance their bodies' response to insulin and control blood sugar levels. Some may need to take insulin shots or use an insulin pump.

Although the precise cause of T2D is not fully understood, there appears to be an inherited genetic component. Approximately sixty percent of affected children in the U.S. have at least one diabetic parent and may have a significant family history of the illness (Ginsburg & Willard, 2013). In some cases, a parent is diagnosed with T2D at the same time as their child. Most individuals who develop this disease are obese. Excess fat makes it difficult for cells to respond to insulin, and physical inactivity further decreases the body's ability to utilize insulin effectively.

In the past, doctors referred to this disease as adult-onset diabetes because it almost exclusively affected obese adults. That characterization is no longer accurate. More children and teenagers are now being diagnosed with T2D, likely because obesity rates among young people in the U.S. have risen significantly. Certain cultural groups are particularly vulnerable to developing T2D, including individuals of Native American, Hispanic/Latino, African-American, and Asian/Pacific Islander heritage. Adolescents are also more likely to develop the illness compared to younger children, partly because of normal hormonal increases that cause insulin resistance during periods of rapid physical development and growth.

Prevalence and Demographics

The dynamics of the diabetes epidemic are changing rapidly. Once considered a disease of Western, affluent societies, T2D has become a global health epidemic. It was also once labeled "a disease of the wealthy," but it is now prevalent among the poor in developing countries. According to the World Diabetes Federation, diabetes affects at least 285 million people globally, a figure expected to exceed 438 million by 2030. Furthermore, two-thirds of all diabetes cases are expected to arise in low- to middle-income nations. The number of adults with impaired glucose tolerance is projected to increase from 344 million to an estimated 472 million by 2030 (Willard & Ginsburg, 2012). This rising prevalence and its associated health complications threaten to reverse economic gains in developing nations. With limited infrastructure for diabetes care, many countries are ill-equipped to manage the disease.

According to the American Diabetes Association, the U.S. accounts for a disproportionately large share of the global diabetes burden. In recent decades, the country has experienced rapid economic development, urbanization, and shifts in nutritional habits, all of which have contributed to a sharp increase in diabetes prevalence within a relatively short period. In 2001, fewer than 1% of U.S. adults had the disease. By 2008, prevalence had reached nearly 10%. It was estimated that more than 92 million U.S. adults had diabetes and 148 million were prediabetic, suggesting that the U.S. had become the global epicenter of the diabetes epidemic.

At the state level, the prevalence of diabetes has reached nearly 20% in some areas. Compared with national averages, residents of certain states develop diabetes at younger ages, at lower levels of excess body weight, and at much higher rates given the same degree of overweight. Women face a greater risk of gestational diabetes, which in turn puts their children at risk for T2D later in life (Atta-ur-Rahman, Reitz & Choudhary, 2010).

T2D Statistics in the U.S. and State-Level Rates

The American Diabetes Association released research estimating that the total cost of clinically diagnosed diabetes had risen to $245 billion from $174 billion in 2009—a 41% increase over five years. This total includes $176 billion in direct healthcare expenses and $69 billion in decreased productivity (Kalhan, Prentice & Yajnik, 2009). The largest components of direct healthcare costs are:

I. Inpatient hospital care (46% of total healthcare costs)
II. Prescription medications to treat diabetes complications (10%)
III. Diabetes supplies and anti-diabetic agents (14%)
IV. Physician office visits (10%)
V. Residential and nursing facility stays (10%)

Individuals with diagnosed diabetes have average annual healthcare expenses of approximately $14,000, of which about $8,000 is attributable to diabetes. On average, people with diagnosed diabetes incur healthcare expenses roughly three times higher than those without the condition (Watve, 2013). Across all cost categories examined, healthcare for people with diagnosed diabetes accounts for more than five percent of total medical care costs in the U.S., with over half of those expenses directly attributable to diabetes itself.