UI study reveals the current rates of diagnosed type 1 and type 2 diabetes in American adults

A new study from the University of Iowa finds that type 2 diabetes remains overwhelmingly the most common type of diabetes diagnosed in American adults who have the disease.

The study found that 8.5 percent of American adults have been diagnosed with type 2 diabetes and .5 percent with type 1 diabetes. Among those who are diagnosed with diabetes, 91.2 percent have type 2 diabetes and 5.6 percent have type 1 diabetes. The study was published this month in the prestigious British Medical Journal.

A portrait of Assistant Professor Wei Bao of the Department of Epidemiology in the University of Iowa College of Public Health.
Wei Bao

Although previous survey studies have reported the rate of diabetes in the United States, the rates by diabetes subtypes—type 1 , type 2, or other type—were virtually unknown. Study lead author Wei Bao, assistant professor of epidemiology in the College of Public Health, says the results are important because it allows health care professionals and policy makers to better allocate resources to treat each type of the disease.

“These two types of diabetes differ not only by their causes, but also by their clinical manifestations and treatment strategies,” he says. Type 1 diabetes is an auto-immune disease that typically develops in childhood. Patients with type 1 diabetes also have problems in producing insulin, and therefore they require insulin treatment for survival.

Type 2 diabetes mostly develops in adulthood and is caused by a complex interplay between genetic and environmental factors such as obesity, unhealthy diet, and physical inactivity. Type 2 diabetes is treated with lifestyle change, medication, and/or insulin.

“Type 2 diabetes can be prevented through lifestyle changes, but so far, there is no established method for preventing type 1 diabetes,” Bao says.

The study is based on data gathered by the CDC’s National Health Interview Survey (NHIS), which is conducted annually by survey-takers who visit peoples’ homes and ask them about their health. Bao says the NHIS is the first and only national health survey that attempts to determine how many adults have each type of diabetes. Since 2016, survey takers started to ask respondents who had been diagnosed with diabetes if they had type 1, type 2, or other type.

Bao acknowledges that the present study has a limitation in that it relies on self-reported data from respondents, so it could be subject to reporting errors. However, he says the results provide a benchmark for future surveys to better determine the prevalence of type 1 diabetes and type 2 diabetes in adults. In addition, this study only has data on diagnosed diabetes and could not determine the rate of undiagnosed diabetes.

Bao emphasizes the need to continue monitoring the dynamic changes of these two types of diabetes in American population. He expects more Americans to report type 2 diabetes as a result of the ongoing obesity epidemic. But he also wouldn’t be surprised if more adults have type 1 diabetes because of improved treatments that keep patients alive longer.

“Type 1 diabetes used to be lethal for children years ago and so children who had the disease had shorter lifespans,” he says. “Now, treatment has been improved to be so effective that a lot of children will survive well into adulthood.”

The study, “Prevalence of diagnosed type 1 and type 2 diabetes among U.S. adults in 2016 and 2017: population based study,” was first authored by Guifeng Xu of the University of Iowa College of Public Health, and co-authored by Yangbo Sun, Linda G. Snetselaar, and Yang Du of the University of Iowa College of Public Health; and Frank B. Hu of Harvard University. It’s published in the current issue of the British Medical Journal.

Additional Media Coverage

Study reveals the current rates of type 1 and 2 diabetes in US adults (Bariatric News)

Current Rates of Diagnosed Type 1 and Type 2 Diabetes in American Adults (Diabetes News)

Current rates of diagnosed type 1 and type 2 diabetes in American adults (Science Daily)

Type 2 makes up more than 90 per cent of diabetes diagnoses in America (Diabetes.co.uk)

Telling the Story Project shares farm safety messages

The Telling the Story Project shares the stories of farmers, agricultural workers, and family and community members who’ve been impacted by injuries, fatalities, or close calls.

“Talking about farm safety makes it normal, and part of farm management, just like the markets or weather or policies are discussed,” says Stephanie Leonard, who helped develop the project. “This is just as important, and actually more, when you’re the person who stands to lose time at work from an injury or your life, even.”

(Read the full story in the Muscatine Journal)

Additional Media Coverage

This Week in Agribusiness (Sept. 15, 2018; part 4 of video)

New farm safety website to debut in time for National Farm Safety Week

Zhu research shows care teams perform well when members accurately know each other’s expertise

Interdisciplinary care teams (ICTs) are increasingly used to care for very complex individuals, such as those with significant mental health and behavioral challenges. A recent joint study by public health researchers at the University of Iowa and the University of Minnesota revealed some teamwork factors in ICTs producing high-quality care.

A portrait of Prof. Xi Zhu of the Department of Health Management and Policy at the University of Iowa College of Public Health.
Xi Zhu

The study, co-authored by Xi Zhu, UI associate professor of health management and policy, and Douglas Wholey, professor emeritus at the University of Minnesota School of Public Health, was published in Health Services Research.

The study examined a type of ICTs for clients with severe mental illness, known as Assertive Community Treatment teams. In particular, the study looked at how their performance is influenced by two main factors: expertise redundancy and what’s known as transactive memory accuracy. Expertise redundancy — the extent to which team members possess highly overlapping knowledge — can complicate a team’s knowledge structure because it reduces role clarity. Transactive memory accuracy is the extent to which team members accurately recognize experts in relevant knowledge domains. It helps team members get assistance from team members who have needed expertise, which leads to better quality decision making, task performance, and care.

The effects of expertise redundancy and transactive memory on ICTs performance were measured by examining their effect on the hospitalization of clients for mental illness.

Overall, teams with low expertise redundancy and the ability to accurately recognize who was an expert in areas had fewer mental health-related hospitalizations. Further, the study showed that transactive memory accuracy had a stronger positive relationship with team performance when expertise redundancy was higher, indicating that it could serve as a cognitive tool for mitigating the negative effect of a group’s complex knowledge structure.

“Both the design and implementation of ICTs are critical for delivering high-quality care,” says Zhu. “The study shows that ICTs with clearly specified knowledge structure and team processes that assure accurate recognition of a team member’s expertise can achieve superior performance.”

Zhu and Wholey are continuing their research on mental health ICTs to examine how team design and leadership affects transactive memory accuracy and how information exchange processes affect team member outcomes, such as individual performance, satisfaction, and team identification.

The study was funded by the National Science Foundation.

This article, written by Charlie Plain, is used courtesy of the University of Minnesota School of Public Health.


UI analysis finds significant increase in number of US children diagnosed with ADHD over 20 years

The number of children in the United States diagnosed with Attention Deficit/Hyperactivity Disorder (ADHD) increased from 6.1 percent to 10.2 percent from 1997 to 2016, according to an analysis from the University of Iowa published in the Journal of the American Medical Association (JAMA) Network Open.

A portrait of Assistant Professor Wei Bao of the Department of Epidemiology in the University of Iowa College of Public Health.
Wei Bao

This upward trend cut across all demographic subgroups, says Wei Bao, assistant professor of epidemiology in the UI College of Public Health and study co-author.

“Our findings indicate a continuous increase in the prevalence of diagnosed ADHD among U.S. children and adolescents,” says Bao.

The study analyzed the health information of more than 186,000 children and adolescents gathered by the U.S. National Health Interview Survey (NHIS), an annual survey of American households conducted by the U.S. Centers for Disease Control and Prevention. The data were collected annually from 1997 to 2016.

The analysis found that 1,243 children age 4 to 17 were reported to have ADHD in the 1997–98 survey, representing 6.1 percent of U.S. children and adolescents. That increased to 1,880 reported cases in 2015–16, representing 10.2 percent of U.S. children and adolescents.

The analysis also found this upward trend across gender, racial, family, and geographic lines. However, it found that not all increases were uniform, and that there were distinct differences within groups.

For instance, in the gender subgroup, the research showed 14 percent of boys were diagnosed with ADHD in 2016, up from 9 percent in 1997. However, only 6.3 percent of girls were diagnosed with ADHD in 2016, up from 3.1 percent in the 1997 survey.

While the number of Hispanic children diagnosed with ADHD jumped from 3.6 percent to 6.1 percent, they are still far less likely to receive a diagnosis than children from other racial groups. White children in the survey were diagnosed with ADHD at a 12 percent rate in 2016, up from 7.2 percent in 1997; 12.8 percent of African American children were diagnosed with ADHD in 2016, up from 4.7 percent in 1997.

The survey also found incidences of the disorder varied significantly by geography. Children in the Western region of the United States were less likely to be diagnosed with ADHD—7 percent in 2016—compared to the Northeast, Midwest, or South, all of which exceeded 10 percent. In 1997, 5 percent of children in the Western states were diagnosed with ADHD, while other regions ranged from 5.5 percent to 6.9 percent.

The NHIS survey did not attempt to find a cause for the increase, but the authors offered some possible factors, such as increased awareness of ADHD and a diminished social stigma for ADHD. Changes that expanded the definition of the disease also may have contributed to the increase.

The authors also say that previous studies also support a role of environmental risk factors, such as exposure to lead or certain pesticides or chemicals during pregnancy and the postnatal period, as well as nutritional deficiencies. Prenatal and perinatal risk factors, including pre-term birth, low birth weight, maternal cigarette smoking, and use of certain medications or illicit substances during pregnancy also have been associated with ADHD risk in previous studies.

The study, “Twenty-year trends in diagnosed attention deficit/hyperactivity disorder among US children and adolescents, 1997–2016,” was published in the Aug. 31 issue of JAMA Network Open. It was first-authored by Guifeng Xu in the UI College of Public Health and co-authored by Lane Strathearn of the UI Roy J. and Lucille A. Carver College of Medicine, Buyun Liu of the UI College of Public Health, and Binrang Yang of Shenzhen Children’s Hospital in China.

The study can be found online at http://jamanetwork.com/journals/jamanetworkopen/fullarticle/10.1001/jamanetworkopen.2018.1471

This story originally appeared in Iowa Now

Additional Media Coverage

ADHD numbers are rising, and scientists are trying to understand why (Washington Post)

About 10 percent of US children are diagnosed with ADHD (CNBC)

10% of US children diagnosed with ADHD, study finds (CNN)

Over Past 20 Years, The Percentage Of Children With ADHD Nearly Doubles (California Healthline)

ADHD Rates Rising Sharply in U.S. Kids (WebMD)

New study finds children’s ADHD diagnoses on the rise (CBS2Iowa)