Decomposition of changes in diabetes inequalities during 2001−2011 and 2011−2018.

Decomposition of changes in diabetes inequalities during 2001−2011 and 2011−2018.</p

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AimsThe overall prevalence of diabetes has increased over the past two decades in the United States, disproportionately affecting low-income populations. We aimed to examine the trends in income-related inequalities in diabetes prevalence and to identify the contributions of determining factors.MethodsWe estimated income-related inequalities in diagnosed diabetes during 2001−2018 among US adults aged 18 years or older using data from the National Health Interview Survey (NHIS). The concentration index was used to measure income-related inequalities in diabetes and was decomposed into contributing factors. We then examined temporal changes in diabetes inequality and contributors to those changes over time.ResultsResults showed that income-related inequalities in diabetes, unfavorable to low-income groups, persisted throughout the study period. The income-related inequalities in diabetes decreased during 2001−2011 and then increased during 2011−2018. Decomposition analysis revealed that income, obesity, physical activity levels, and race/ethnicity were important contributors to inequalities in diabetes at almost all time points. Moreover, changes regarding age and income were identified as the main factors explaining changes in diabetes inequalities over time.ConclusionsDiabetes was more prevalent in low-income populations. Our study contributes to understanding income-related diabetes inequalities and could help facilitate program development to prevent type 2 diabetes and address modifiable factors to reduce diabetes inequalities.</div

Decompositions of income-related inequalities in diabetes in 2001, 2011, and 2018.

Decompositions of income-related inequalities in diabetes in 2001, 2011, and 2018.</p

Income-related inequalities in diabetes by sex, age, and race/ethnicity among US adults aged ≥ 18 years, 2001–2018.

The concentration index (CI) measures the inequality in diabetes prevalence over the distribution of income. Negative CIs indicate that diabetes was concentrated among lower-income groups, and a larger CI (in absolute value) indicates a greater degree of inequality.</p

Relative contributions of determining factors to income-related inequalities in diagnosed diabetes, 2001−2018.

For each year, the length of the sub-bar indicated the numeric value of each factor’s relative contribution to the overall CI, and the sum of numeric values from all factors was equal to the overall CI.</p

Risk Factors Amenable to Primary Prevention of Type 2 Diabetes Among Disaggregated Racial and Ethnic Subgroups in the United States

Race and ethnicity data disaggregated into detailed subgroups may reveal pronounced heterogeneity in diabetes risk factors. We therefore used disaggregated data to examine the prevalence of type 2 diabetes risk factors related to lifestyle behaviors and barriers to preventive care, among adults in the United States. We conducted a pooled cross-sectional study of 3,437,640 adults aged ≥18 in the United States without diagnosed diabetes from the Behavioral Risk Factor Surveillance System (2013–2021). Self-reported race and ethnicity included: Hispanic (Cuban, Mexican, Puerto Rican, Other Hispanic), Non-Hispanic (NH) American Indian/Alaska Native, NH Asian (Chinese, Filipino, Indian, Japanese, Korean, Vietnamese, Other Asian), NH Black, NH Pacific Islander (Guamanian/Chamorro, Native Hawaiian, Samoan, Other Pacific Islander), NH White, NH Multiracial, NH Other. Risk factors included: current smoking, hypertension, overweight or obesity, physical inactivity, being uninsured, not having a primary care doctor, healthcare cost concerns, and no physical exam in the past 12 months. Prevalence of hypertension, lifestyle factors and barriers to preventive care showed substantial heterogeneity among both aggregated, self-identified racial and ethnic groups and disaggregated subgroups. For example, the prevalence of overweight or obesity ranged from 50.8% (95% confidence interval [CI], 49.1–52.5) among Chinese adults to 79.8% (73.5–84.9) among Samoan adults. Prevalence of being uninsured among Hispanic subgroups ranged from 11.4% (10.9–11.9) among Puerto Rican adults to 33.0% (32.5–33.5) among Mexican adults. These findings underscore the importance of using disaggregated race and ethnicity data to accurately characterize disparities in type 2 diabetes risk factors and access to care.</p

Table_1_Clinical performance and health equity implications of the American Diabetes Association’s 2023 screening recommendation for prediabetes and diabetes.docx

IntroductionThe American Diabetes Association (ADA) recommends screening for prediabetes and diabetes (dysglycemia) starting at age 35, or younger than 35 years among adults with overweight or obesity and other risk factors. Diabetes risk differs by sex, race, and ethnicity, but performance of the recommendation in these sociodemographic subgroups is unknown.MethodsNationally representative data from the National Health and Nutrition Examination Surveys (2015-March 2020) were analyzed from 5,287 nonpregnant US adults without diagnosed diabetes. Screening eligibility was based on age, measured body mass index, and the presence of diabetes risk factors. Dysglycemia was defined by fasting plasma glucose ≥100mg/dL (≥5.6 mmol/L) or haemoglobin A1c ≥5.7% (≥39mmol/mol). The sensitivity, specificity, and predictive values of the ADA screening criteria were examined by sex, race, and ethnicity.ResultsAn estimated 83.1% (95% CI=81.2-84.7) of US adults were eligible for screening according to the 2023 ADA recommendation. Overall, ADA’s screening criteria exhibited high sensitivity [95.0% (95% CI=92.7-96.6)] and low specificity [27.1% (95% CI=24.5-29.9)], which did not differ by race or ethnicity. Sensitivity was higher among women [97.8% (95% CI=96.6-98.6)] than men [92.4% (95% CI=88.3-95.1)]. Racial and ethnic differences in sensitivity and specificity among men were statistically significant (P=0.04 and P=0.02, respectively). Among women, guideline performance did not differ by race and ethnicity.DiscussionThe ADA screening criteria exhibited high sensitivity for all groups and was marginally higher in women than men. Racial and ethnic differences in guideline performance among men were small and unlikely to have a significant impact on health equity. Future research could examine adoption of this recommendation in practice and examine its effects on treatment and clinical outcomes by sex, race, and ethnicity.</p