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Medication News & Update

   The glycohemoglobin test or more commonly now referenced as the A1C value gives a picture of the patients average blood glucose levels over the last 120 days. However, the last 30 days contribute more to the value than do the previous 90-120 days. Therefore if significant changes in plasma glucose levels occur within the last 30 days it can contribute meaningfully to the A1C value.

    The Diabetes Control and Complications Trial (DCCT) one of the benchmark diabetes trials within the past few years provides the greatest amount of data relating these two values. They developed or showed a linear relationship in that trial of A1C values to mean plasma glucose(MPG) levels. That relationship can be expressed mathematically as:

                     MPG = (35.6 x A1c) -77.3

the calculated value is approximate see the reference table below do the math and compare. ?use the percent as a whole number not 0.06 in your calculation.

AIC          mg/dl glucose level      Calculated

4                     65                          65.1

5                     100                        100.7

6                     135                        136.3

7                     170                        171.9

8                     205                        207.5

9                     240                        243.1        

10                   275                        278.7

11                   310                        314.3

12                   345                        349.9

Each 1% change in A1c value represents a change of approximately 35mg/dl

These values and the relationship apply only to methods used to determine the A1C which are traceable to the DCCT reference.