Association of Sex and Other Demographic Characteristics with Hemoglobin A1c in Older Adults with Type 1 Diabetes: Cross-sectional analysis of the U.S. Premier Healthcare Database

Objective

In type 1 diabetes, results for hemoglobin A1c (HbA1c) sex-based differences are mixed with limited data in later ages. The study objective was to determine if female sex is independently associated with higher HbA1c in the United States older adult population.

Research Design and Methods

A cross-sectional analysis was performed on real world Premier Healthcare data from January 2020–December 2022 examining adults with type 1 diabetes, ages 55-75. Multivariate linear and logistic regression models were used to determine demographic variables independently associated with HbA1c. Predictor variables included age, sex, race, ethnicity, insurance payor, testing location, marital status, atherosclerotic cardiovascular disease.

Results

Of 12,088 individuals with HbA1c data (52.4% women, mean age 64.7 ± 5.8 years), HbA1c was 0.13% (95% CI: [0.08, 0.18], P <0.001) higher on average in females and 0.81-0.97% higher in Black patients adjusting for all other variables. Female sex (unadjusted odds ratio 1.13, 95% CI: [1.05, 1.21], P <0.001, adjusted odds ratio [aOR] 1.16, 95% CI: [1.07, 1.26], P <0.001), Black compared to White race (aOR 1.78, 95% CI: [1.49, 2.12], P <0.001), and Medicaid compared to Managed Care payor (aOR 1.63, 95% CI: [1.28, 2.07], P <0.001) were independently associated with increased odds of HbA1c above target, ≥7% for ages 55-64 and ≥8.5% for ages ≥ 65.

Conclusions

In this cohort with type 1 diabetes, females experienced slightly higher HbA1c and higher odds of HbA1c above recommendations. Individuals with Black race and Medicaid insurance payor experienced clinically significantly higher HbA1c levels. Further interventions to address HbA1c disparities are needed.

Twitter summary

Hemoglobin A1c was slightly higher for women, ages 55 to 75, with type 1 diabetes in a real world healthcare database. Major racial and insurance based hemoglobin A1c disparities were observed.

Article Highlights

• Why did we undertake this study?

  • Limited, mixed data exists examining hemoglobin A1c (HbA1c) sex-differences in people with type 1 diabetes in later ages.

• What is the specific question(s) we wanted to answer?

  • In older age groups, do women have higher HbA1c levels, adjusting for demographic characteristics which influence HbA1c?

• What did we find?

  • HbA1c was 0.13% higher in women compared to men adjusting for other variables. Women had higher odds of HbA1c above age-based targets.

  • Black race was associated with a 0.81% and 0.97% higher HbA1c compared to White and Asian races respectively.

• What are the implications of our findings?

  • Mechanistic study is needed to understand higher HbA1c in women at these age groups, and further intervention is needed to reduce health disparities.