Purpose
To determine the extent to which sociodemographic factors and glucose control affect the incidence of developing diabetic macular edema (DME).
Methods
All enrollees with diabetes mellitus age ≥ 30 years who were continuously enrolled in a large managed care network for at least three years and had one or more visits to an eye-care provider were identified. Enrollees with pre-existing DME were excluded. Incidence rates of DME were determined for individuals of different sociodemographic backgrounds and for persons with different baseline levels of glycosylated hemoglobin (HbA1c).
Results
Of the 447407 individuals in the medical plan who met the inclusion criteria, 6473 persons (0.63%) developed DME. The DME incidence rate increased from 0.34% among 30-40 year olds to 0.89% among 70-80 year olds. Blacks (0.78%) and Latinos (0.68%) had higher incidence rates of DME relative to whites (0.62%) and Asians (0.55%). Enrollees with college diplomas had lower DME incidence than those with < high school education (0.57% vs. 0.74%). Likewise, those with incomes <$30,000 had a higher incidence of DME compared to those earning over $125,000 (0.76% vs. 0.56%). DME incidence rose dramatically among those with poor glucose control from 0.24% for those with an HbA1c of 6-7 to 0.90% for those with an HbA1c of 9-10, to 1.27%for those with an HbA1c of 11-12. Compared to those with HbA1cs of 6-7, persons with HbA1cs of 11-12 had > 5 fold increased risk of developing DME (RR=5.23, 2.77-9.86).
Conclusions
Incidence of DME is influenced by sociodemographic factors as well as baseline HbA1c levels. The DME incidence estimates generated from this analysis can be used to make projections of the number of patients in the United States who will develop DME over the next 10 years and to help health policy-makers anticipate the resources that will be required to care for persons who develop DME in the coming years.
Keywords: 463 clinical (human) or epidemiologic studies: prevalence/incidence •
460 clinical (human) or epidemiologic studies: health care delivery/economics/manpower