Relative clinical usefulness of glycosylated serum albumin and fructosamine during short-term changes in glycemic control in IDDM.

Serial changes in glycosylated blood proteins and direct measures of glycemia were studied in 100 subjects with insulin-dependent diabetes mellitus (IDDM) over a 6-wk period while attempts were made to improve glycemic control. All measures of glycemic control improved significantly (P less than .001). Mean +/- SE glycosylated hemoglobin (HbA1) fell from 9.1 +/- 0.2 to 8.0 +/- 0.1%, glycosylated serum albumin (GSA) from 9.8 +/- 0.4 to 7.3 +/- 0.3%, and fructosamine from 3.92 +/- 0.08 to 3.42 +/- 0.07 mM. Fasting blood glucose levels fell from 11.1 +/- 0.6 to 8.1 +/- 0.7 mM mean blood glucose levels from 12.5 +/- 0.3 to 8.8 +/- 0.03 mM, and the M value from 118 +/- 7 to 40 +/- 3 U. Mean percentage changes in direct measures of glycemia (32-66%) and GSA (29%) were greater than for fructosamine (11%) or HbA, (12%) levels (P less than .001). Furthermore, the correlation between the change in GSA and changes in direct measures of glycemia over the initial 2-wk period was significantly different from the corresponding correlations between direct measures of glycemia and fructosamine over this period (P less than .05-.01). Changes in GSA also correlated more closely than HbA1 or fructosamine did with direct measures of glycemia after 4 and 6 wk. The Spearman rank-correlation coefficient (rs) of absolute changes in GSA, fructosamine, and HbA1 after 2-6 wk ranged from 0.27 to 0.57, confirming that the three measures responded differently to changing glycemic control.(ABSTRACT TRUNCATED AT 250 WORDS)