Interinstitutional variation in glycohemoglobin monitoring and glycemic control of diabetic patients.
OBJECTIVE
To compare how frequently institutions monitor glycohemoglobin in diabetic patients, the level of glycemic control achieved and to identify institutional factors associated with higher rates of monitoring and lower glycohemoglobin levels.


METHODS
A total of 212 institutions retrospectively abstracted laboratory and outpatient records of up to 30 diabetic patients who had initial glycohemoglobin monitoring performed in their laboratories. Data from a cohort of 5586 diabetic patients and 17 365 assays were analyzed.


RESULTS
Overall, 31.3% of patients underwent glycohemoglobin monitoring at least quarterly, the frequency recommended by the American Diabetes Association (ADA) to stabilize patients at target hemoglobin A(1c) (HbA(1c)) levels. A total of 64.9% of patients were monitored at least semiannually, the ADA recommendation for patients with stable diabetes in glycemic control (final HbA(1c) level <7%). When we compared the top and bottom deciles of the 212 institutions, there was more than an eightfold difference in the proportion of patients monitored at least quarterly and more than a twofold difference in the proportion of patients monitored at least semiannually. Glycemic control was assessed by examining the value of the last glycohemoglobin determination on record after at least 8 months of management. For all 5586 diabetic patients, the median value of the last HbA(1c) assay was 7.4%. Comparing the top and bottom deciles, there was almost a fourfold difference among institutions in the proportion of diabetic patients in glycemic control. The use of reminders to order glycohemoglobin monitoring was associated with higher rates of semiannual monitoring (P <.05) and tighter glycemic control (P <.05). In addition, patients who were monitored more frequently experienced glycohemoglobin reductions of greater magnitude (P <.001). The presence of diabetes clinics and the use of rapid methods for testing glycohemoglobin were not associated with monitoring frequency or glycohemoglobin levels.


CONCLUSIONS
There is wide interinstitutional variation in the frequency with which diabetic patients are monitored and the level of glycemic control achieved. The use of prompting systems to remind providers to order glycohemoglobin monitoring was associated with more frequent monitoring and superior glycemic control.
Valenstein
P N
PN
Department of Pathology, St Joseph Mercy Hospital, Ann Arbor, MI 48106-0995, USA. valenstp@allegiancellc.com
Walsh
M K
MK
Pappas
A A
AA
Howanitz
P J
PJ
D001786:Blood Glucose / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000097:blood* / Q000628:therapy; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D010349:Patient Compliance; D011786:Quality Control; D012044:Regression Analysis; D012189:Retrospective Studies; D013997:Time Factors
D001786:Blood Glucose; D006442:Glycated Hemoglobin