TABLE 2.
Effects of specific glucose measurements and A1C in three multiple linear regression models
| All diabetes (n = 427) | Type 1 diabetes (n = 268) | Type 2 diabetes (n = 99) |
Type 2 diabetes (n = 60) |
|
|---|---|---|---|---|
| Non–insulin-treated | Insulin-treated | |||
| A | ||||
| Prebreakfast | 0.122 (0.086–0.157)* | 0.107 (0.065–0.149)* | 0.116 (0.031–0.201)* | 0.179 (0.088–0.270)* |
| Postbreakfast | 0.020 (−0.011 to 0.050) | 0.000 (−0.37 to 0.038) | 0.029 (−0.035 to 0.093) | 0.078 (0.008–0.148)* |
| Prelunch | 0.097 (0.059–0.134)* | 0.130 (0.086–0.175)* | 0.055 (−0.053 to 0.164) | 0.002 (−0.088 to 0.091) |
| Postlunch | 0.108 (0.071–0.145)* | 0.120 (0.077–0.164)* | 0.092 (−0.009 to 0.192) | 0.103 (0.015–0.191)* |
| Predinner | 0.093 (0.058–0.128)* | 0.053 (0.012–0.095)* | 0.085 (−0.034 to 0.204) | 0.140 (0.052–0.229)* |
| Postdinner | 0.052 (0.018–0.085)* | 0.077 (0.037–0.117)* | 0.066 (−0.021 to 0.153) | −0.012 (−0.109 to 0.085) |
| A1C variation explained† | 41% | 39% | 49% | 43% |
| B | ||||
| All preprandial | 0.315 (0.267–0.362)* | 0.288 (0.227–0.349)* | 0.259 (0.164–0.354)* | 0.340 (0.207–0.473)* |
| All postprandial | 0.167 (0.123–0.211)* | 0.186 (0.129–0.242)* | 0.177 (0.094–0.259)* | 0.134 (0.024–0.245)* |
| Difference pre-/postprandial‡ | P < 0.01 | P = 0.07 | P = 0.34 | P = 0.08 |
| A1C variation explained† | 40% | 37% | 48% | 38% |
| C | ||||
| All preprandial | 0.257 (0.204–0.310)* | 0.244 (0.178–0.310)* | 0.136 (0.004–0.268)* | 0.312 (0.176–0.447)* |
| All postprandial | 0.163 (0.120–0.206)* | 0.183 (0.128–0.239)* | 0.182 (0.102–0.262)* | 0.106 (−0.008 to 0.220) |
| Nocturnal SMBG | 0.071 (0.040–0.102)* | 0.060 (0.022–0.098)* | 0.117 (0.027–0.207)* | 0.069 (−0.019 to 0.156) |
| Difference pre-/postprandial1 | P = 0.04 | P = 0.28 | P = 0.64 | P = 0.07 |
| A1C variation explained† | 41% | 38% | 50% | 39% |
| A1C variation explained by average blood glucose§ | 53% | 51% | 56% | 53% |
Data are β coefficients (in % A1C per mmol/l) from multiple linear regression models (95% CI), unless otherwise indicated. A: model including mealtime measurements. B: model including mean of all pre- and postprandial values. C: model with both prandial and nocturnal blood glucose.
*P value for estimates <0.05.
†The proportion of A1C variation (SD) explaned by the glucose features of each model.
‡P values from test of difference between pre- and postprandial estimates.
§For comparison, the A1C variation explained by average blood glucose is illustrated.