Table 3

Multivariate regression analysis of factors influencing A1C

At time of diabetes-level hyperglycemia (n = 1,335)
    Random plasma glucose (mg/dl)0.0180.0005<0.0001
    Time of day of random glucose (hours since midnight)0.1020.016<0.0001
    Actual date (days since 10/1/2002)0.000020.000130.8685
    Age (years)−0.00490.00330.1381
    BMI (kg/m2)0.002970.006580.6516
    Black race0.2450.0690.0004
At time of diagnosis of diabetes (n = 2,144)
    Random plasma glucose0.01840.0004<0.0001
    Time of day of random glucose0.0320.0130.0166
    Actual date−0.000010.000120.9273
    Black race0.3830.065<0.0001
At time of initial prescription of diabetes medication (n = 1,686)
    Random plasma glucose0.01660.0005<0.0001
    Time of day of random glucose0.0270.0180.1244
    Actual date−0.000060.000080.4150
    Black race0.4050.082<0.0001
  • Adjustment also included medical center (not shown). A1C is the dependent variable in the model; white race was the racial reference value. Positive estimate values show the extent to which unit changes in the factor contribute to higher A1C values, and negative estimate values show the converse.