Effect of immediate hemoglobin A1c results on treatment decisions in office practice

To assess the effect of an immediately available hemoglobin A1c (HbA1c) result on glycemic control and physician decisions about pharmacologic therapy in an office practice. In a 1-year retrospective review of medical records, HbA1c results were analyzed in 115 patients beyond the age of 65 years, who had type 2 diabetes and were referred for the first time to a private endocrinology practice between April 1, 1997, and March 31, 1998. These patients were classified into two groups: group A (N = 93, insured by standard Medicare) had immediate HbA1c results (during the patient encounter) and group B (N = 22, insured by Medicare health maintenance organization [HMO]) had commercial laboratory HbA1c results available within 2 to 3 days. We reviewed the changes in the HbA1c level during the 12-month period and the presence or absence of a change in therapy at each visit. HbA1c levels were measured by ion-exchange low-pressure liquid chromatography in group A and by one of three capitated commercial laboratories (depending on HMO contracts) in group B. At the end of the 12 months, the mean HbA1c decrease was 1.03 +/- 0.33% in group A and 0.33 +/- 0.83% in group B. During the first visit, 52% of the patients in group A had pharmacologic treatment interventions, whereas only 27% in group B had such interventions. Rapid availability of the HbA1c results during the clinical encounter improves the ability of the physician to make appropriate therapeutic decisions and results in improved glycemic control.