Objectives: We investigated whether there were differences in glycemic control in older compared with younger subjects with type 2 diabetes mellitus enrolled in the Fremantle Diabetes Study, a prospective study of diabetes care, control, and complications in an urban setting.
Design: Cross-sectional observational study.
Setting: University teaching hospital clinical research center.
Participants: A total of 1,205 patients with type 2 diabetes mellitus, 404 (33.3%) of whom were aged over 70 years and 83 (6.9%) aged over 80 years.
Measurements: Fasting plasma glucose, HbA1c, body mass index, and waist/hip ratio.
Results: In multiple linear regression analysis, age was inversely associated with glycemic control whereas duration of diabetes and treatment with either oral hypoglycemic agents or insulin were positively associated with glycemic control. For most age groups there was a significant worsening of glycemic control with duration of diabetes. Octogenarians differed significantly from younger age groups in that those with longer diabetes duration did not demonstrate the increase in hyperglycemia seen in other age groups. As a result, significantly greater proportions of these oldest diabetic subjects had satisfactory glycosylated hemoglobin levels compared with younger subjects.
Conclusions: Octogenarians do not demonstrate the usual progressive deterioration of glycemic control with diabetes duration seen in type 2 diabetes mellitus. The reasons for this difference are unknown but are likely to have clinical significance with regard to therapy and the development of diabetic complications.