Developing a Diabetes-Specific Registry to Reduce Disparities of Long-Term Morbidity in San Antonio, Texas

Objective:In 2007, the San Antonio Metropolitan Health District was granted authority by the Texas Legislature to initiate a Hemoglobin A1c (HbA1c) Registry. 

Methods:HbA1c is the biomarker which assesses long-term glucose control.  HbA1c test results were provided by four major clinical labs in the San Antonio area.  Currently, the Registry contains HbA1c tests results for 233,696 unique individuals who were tested at least once for HbA1c over period January 2005-June 2009.  

Results:Among the Registry cohort, 55% were female and 45% were male and the largest proportion is 50-64 years of age.  Although, the overall annual average A1c test result per patient was 7.2%, this value was significantly higher among males (7.3%) when compared to females (7.02%, p < 0.01)).  Upon further examination, we found that the annual average A1c test results among the “working adult” population 35-64 years of age (7.5%) were significantly higher when compared to the annual average A1c across all age groups (p< 0.001).  Additionally, we observed significant disparities in geographic-specific trends of enrollees with poor glucose control in 26 of the 72 zip codes in Bexar County. With respect to annual testing, only 67.4% of the Registry’s 2007 enrollees were re-tested at least once in 2008. Of those re-tested in 2008, 54% improved their annual average A1c whereas 42% worsened. 

Conclusion:San Antonio A1c Registry is the first biomarker-based registry in the State of Texas.  This project provides the evidence basis for future chronic disease program development and public health intervention in San Antonio and other jurisdictions.