Estimation of glycated hemoglobin (HbA1c) - pattern of ordering by clinicians in Christian Medical College, Vellore

Background of the study - Glycated hemoglobin (HbA1c) is formed non-enzymatically by condensation of glucose or other reducing sugars with alpha - and beta-globin chains of hemoglobin A. Blood levels of HbA1c have been used for monitoring the degree of control of glucose levels in diabetic patients since 1976. The American Diabetes Association currently recommends that HbA1c can be used as a diagnostic tool as well. Aim of the study -The aim of this study was to determine the pattern of ordering of the test for estimation of glycated hemoglobin (HbA1c) by clinicians in broad and super specialities in medicine, in CMC, Vellore. Materials and methods -Requests from clinicians for estimation of HbA1c during the first week in October 2014 were tabulated. These data were collected from the Computerized Hospital Information Processing System (CHIPS) of CMC, Vellore. The data were categorized into requests from broad and super specialities in medicine. Results- The total number of tests done to estimate HbA1c during the period of the study was 1914. Of these, 1705 (89.1 percent) were for out-patients and 209 (10.9 percent) were for in-patients, 1089 (56.9 percent) tests were done for males and 825 (43.1 percent) were for females. Eight hundred and ninety one of these tests (46.6 percent) were ordered by clinicians in the broad specialities in medicine, while 1023 (53.4 percent) were from the super specialities. Of the tests ordered from the broad specialities, 61.4 percent of the tests were ordered as a diagnostic test (done for the first time in patients who were not previously known to be diabetic) and 38.6 percent as a monitoring test for known diabetic subjects. In the tests ordered from the super specialities, 48.5 of the tests were ordered as a diagnostic test and 51.5 percent as a monitoring test. Conclusion -It appears from the data studied that clinicians in the broad specialties used estimation of HbA1c as a diagnostic test to a greater extent than as a monitoring test. The reverse appeared to be the case with clinicians in the super specialties.