New directions in incidence and prevalence of diagnosed diabetes in the USA

Abstract

Objective: To determine whether diabetes prevalence and incidence has remained flat or changed direction during the past 5 years.

Research design and methods: We calculated annual prevalence and incidence of diagnosed diabetes (type 1 and type 2 combined) for civilian, non-institutionalized adults aged 18-79 years using annual, nationally representative cross-sectional survey data from the National Health Interview Survey from 1980 to 2017. Trends in rates by age group, sex, race/ethnicity, and education were calculated using annual percentage change (APC).

Results: Overall, the prevalence of age-adjusted, diagnosed diabetes did not change significantly from 1980 to 1990, but increased significantly (APC 4.4%) from 1990 to 2009 to a peak of 8.2 per 100 adults (95% CI 7.8 to 8.6), and then plateaued through 2017. The incidence of age-adjusted, diagnosed diabetes did not change significantly from 1980 to 1990, but increased significantly (APC 4.8%) from 1990 to 2007 to 7.8 per 1000 adults (95% CI 6.7 to 9.0), and then decreased significantly (APC -3.1%) to 6.0 (95% CI 4.9 to 7.3) in 2017. The decrease in incidence appears to be driven by non-Hispanic whites with an APC of -5.1% (p=0.002) after 2008.

Conclusions: After an almost 20-year increase in the national prevalence and incidence of diagnosed diabetes, an 8-year period of stable prevalence and a decrease in incidence has occurred. Causes of the plateauing and decrease are unclear but the overall burden of diabetes remains high and deserves continued monitoring and intervention.

Keywords: adult diabetes; incidence; public health/surveillance.

Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1

Trends in age-adjusted diagnosed diabetes prevalence and incidence among adults aged 18–79 years, 1980–2017. Data are from the Centers for Disease Control and Prevention’s (CDC) National Health Interview Survey. Dots are observed annual values; the lines are modeled using Joinpoint Trend Analysis Software. The dotted lines indicate no significant trend; solid lines indicate a significant annual percentage change. Arrows indicate joinpoints (changes in trend). The 2000 US Census was used for age adjustment using age groups 18–44, 45–64, and 65–79 years.

Figure 2

Prevalence of diagnosed diabetes among adults aged 18–79 years by demographic variables, 1990–2017. Data are from the Centers for Disease Control and Prevention’s (CDC) National Health Interview Survey. Dots are observed values; the lines are modeled using Joinpoint Trend Analysis Software. The dotted lines indicate no significant trend; solid lines indicate a significant annual percentage change. Arrows indicate joinpoints (changes in trend). The 2000 US Census was used for age adjustment using age groups 18–44, 45–64, and 65–79 years.

Figure 3

Incidence of diagnosed diabetes among adults aged 18–79 years by demographic variables, 1990–2017. Data are from the Centers for Disease Control and Prevention’s (CDC) National Health Interview Survey. Dots are observed values; the lines are modeled using Joinpoint Trend Analysis Software. The dotted lines indicate no significant trend; solid lines indicate a significant annual percentage change. Arrows indicate joinpoints (changes in trend). The 2000 US Census was used for age adjustment using age groups 18–44, 45–64, and 65–79 years.