Abstract P142: Trends and Racial/Ethnic Differences in Age at Diagnosis of Type 1 and Type 2 Diabetes Among Adults in the United States, 2016-2022

Abstract

Introduction: Age at diagnosis of diabetes and diabetes type are associated with medical costs, lost productivity, vascular complications, and premature mortality that affect people disproportionately by race/ethnicity. However, age at diagnosis of diabetes by diabetes type and race/ethnicity along with their temporal trends are unclear. Hypothesis: We assessed the hypothesis that different trends and racial/ethnic differences in age at diagnosis of diabetes by diabetes type existed between 2016 and 2022. Methods: Adults aged 18 years or more were included from the National Health Interview Survey, 2016-2022. Type and age at diagnosis of diabetes were self-reported. Trends in age at diagnosis of type 1 diabetes (T1D) and type 2 diabetes (T2D) and in proportions of people with T1D or T2D diagnosed at different ages were assessed by linear and logistic regressions adjusted for sex and race/ethnicity, respectively. Racial/ethnic differences in age at diagnosis of T1D and T2D were estimated using Rao-Scott chi-square test. Results: Of 16,063 participants, 1,551 individuals had T1D with a mean [SE] age of 53.1 [0.6] years; 48.7% were women and 57.9% non-Hispanic White. T2D was found in 14,512 individuals with a mean [SE] age of 62.5 [0.2] years; 48.5% were women and 53.7% non-Hispanic White. The mean [SE] diagnosis age of T1D decreased from 37.5 [1.4] years in 2016 to 35.6 [1.4] years in 2022 ( P for trend = 0.03). During the same period for T2D, the mean [SE] diagnosis age increased from 48.7 [0.4] years to 49.2 [0.3] years ( P for trend <0.001). From 2016 to 2022, the proportion of people with T1D and T2D diagnosed at <45 years increased by 8% and decreased by 3% annually, respectively ( P for trend ≤0.01); the proportion of people with T1D and T2D diagnosed at ≥60 years decreased by 9% and increased by 3% annually, respectively ( P for trend ≤0.03). All results were adjusted for sex and race/ethnicity. Compared with non-Hispanic Whites, the mean diagnosis age of T1D was 7.8, 7.9, and 11.2 years higher whereas of T2D was 5.0, 6.4, and 2.5 years lower, respectively, in non-Hispanic Black, Hispanic, and non-Hispanic Asian people (all P for difference ≤0.002). Conclusions: In US adults, the mean age at diagnosis of T1D significantly decreased, whereas of T2D significantly increased from 2016 to 2022. Substantial differences in diagnosis age of T1D and T2D by race/ethnicity existed.