A study that compared total U.S. diabetes diagnoses over a 26-year period found that while the prevalence nearly doubled, from 5.5 to 10.8 percent, the proportion of missed cases of diabetes dropped significantly during the same period, from 16.3 to 10.9 percent. The study, led by researchers at the Johns Hopkins Bloomberg School of Public Health, suggests that increased screening by primary health care providers is yielding a bigger proportion of diagnoses and, as such, more opportunities for treatment.
Some estimates put as many as one-quarter to one-third of diabetes cases as undiagnosed, a worrisome gap considering the growing number of diabetes cases in the United States and around the globe. These estimates are thought to overstate the number of undiagnosed diabetes cases, because they tend to use definitions that are not consistent with American Diabetes Association guidelines for diagnosing diabetes, which require a “confirmatory” blood test.
The study suggests that in 2015 the total number of U.S. adults with diabetes was approximately 25.5 million, up from 21.4 million adults in 2010, with approximately 11 percent of cases undiagnosed. In contrast, the Centers for Disease Control and Prevention (CDC), which does not use a confirmatory standard, estimates there currently are 30.1 million adults with diabetes in the United States, and 23.8 percent are undiagnosed.