HbA(1c) levels among American Indian/Alaska Native adults

Type 2 diabetes is a major public health problem among many American Indian/Alaska Native communities. Elevated levels of HbA(1c) have been observed in younger American Indian/Alaska Native adults. The objectives of this study were: 1) to determine whether HbA(1c) levels were elevated among younger American Indian/Alaska Native adults nationally and, if so, 2) to determine the relationship between HbA(1c) levels and age due to treatment type, BMI, renal disease, duration of diabetes, survival, or a poor diabetes health care index.

The national Indian Health Service Diabetes Care and Outcomes Audit was completed for a total of 11,419 American Indian/Alaska Native adults with type 2 diabetes from tribes across the U.S. in 1998. Glucose control was assessed by HbA(1c). BMI, diabetes duration, treatment type, and proteinuria were assessed from the Diabetes Care and Outcomes Audit data. To assess diabetes quality of care, an index was developed from six standard of care Diabetes Care and Outcomes Audit variables.

We found HbA(1c) level decreased with increasing age. HbA(1c) levels were 9.2, 8.9, 8.8, 8.3, and 7.8 for ages 18-39, 40-49, 50-59, 60-69, and > or =70 years, respectively (P < 0.0001). This inverse relationship was not accounted for by differences in BMI, diabetes duration, treatment type, proteinuria, or health care index.

Among American Indian/Alaska Native adults, HbA(1c) levels were highest in the youngest age-group. With increasing numbers of young American Indian/Alaska Native adults with diabetes, poorer glucose control is expected to bring concomitant increased morbidity and mortality unless more effective and efficient interventions are developed to improve glucose control among young American Indian/Alaska Native adults.