The researchers used 2 well-known national data sets to track a cohort of patients and found that death rates from diabetes are closer to 12%, not the 3% to 4% recorded on death certificates.
Diabetes has been recognized by CDC as the 7th-leading cause of death, but a new study found that the toll may be higher than researchers thought.
A study from Boston University public health researcher Andrew Stokes, PhD, and the University of Pennsylvania’s Samuel Preston, PhD, found that the share of deaths due to diabetes is as high as 12%, or 3 times higher than what is listed on death certificates. The study was published Wednesday in the journal PLoS ONE.
Stokes and Preston used 2 large data sets, from the National Health Interview Survey (NHIS) and the National Health and Nutrition Examination Survey (NHANES) to track a cohort between ages 30 and 84. They captured survey respondents covering the period 1997 to 2009 and followed them through 2011. The researchers reported “a high degree of consistency between the data sets,” both in how diabetes was defined and in the estimates of death due to the disease.
They found the share of deaths attributable to diabetes was 11.5% based on self-reports to NHIS and 11.7% based on self-reports to NHANES. Using glycated hemoglobin (A1C), which NHANES reports, the death rate rises to 11.8%. Among those who were obese, meaning they had a body mass index of 30 kg/m2 or higher, the rate rose to 19.4%.
By contrast, the percentage of deaths in which diabetes is formally listed as the underlying cause is 3.3% to 3.7%. Even CDC, in its 2016 update of diabetes statistics, says that death rates “may be underreported.”
“Our results demonstrate that diabetes is a major feature on the landscape of American mortality, and they reinforce the need for robust population-level interventions aimed at diabetes prevention and care,” Stokes and Preston wrote.
Diabetes has received increased attention as healthcare moves from a fee-for-service to a value-based system, since the disease consumes so many healthcare dollars. The American Diabetes Association’s most recent estimate puts the annual cost of the nation at $245 billion in healthcare and lost productivity. In Medicare, $1 of every $3 spent is tied to diabetes.
Quality care indicators, especially those used by Medicare, emphasize treatment of diabetes, as accountable care organizations are judged based on how well they control patients’ A1C, blood pressure, and low-density lipoprotein (or “bad”) cholesterol.
As the researchers noted, diabetes causes a host of comorbidities, including renal failure, peripheral arterial disease, peripheral neuropathy, cognitive impairment, and blindness. It is also a leading cause of heart disease. Thus, they wrote, “the frequency with which diabetes is listed as the underlying cause of death is not a reliable indicator of the actual contribution to the national mortality profile.”
Stokes A, Preston SH. Deaths attributable to diabetes in the United States: comparison of data sources and estimation approaches. PLoS ONE 2017; 12(1): e0170219. doi:10.1371/journal.pone.0170219