Table 3

The crude and adjusted ORs of HbA1c>6.0%, impaired glucose regulation and insulin resistance according to daytime napping

Dependent variableIndependent variableCrude OR (95% CI)p ValueAdjusted OR* (95% CI)p ValueAdjusted OR† (95% CI)p ValueAdjusted OR‡ (95% CI)p Value
HbA1C>6.0%Napping
 No nap1.01.01.01.0
 ≤1 h1.13 (0.98 to 1.30)0.1021.05 (0.91 to 1.22)0.4911.05 (0.91 to 1.22)0.5161.28 (1.09 to 1.49)0.002§
 >1 h1.24 (1.04 to 1.48)0.018§1.16 (0.97 to 1.38)0.1121.13 (0.94 to 1.36)0.1861.26 (1.04 to 1.53)0.018§
IGRNapping
 No nap1.01.01.01.0
 ≤1 h1.05 (0.94 to 1.17)0.3941.06 (0.95 to 1.19)0.3131.06 (0.94 to 1.18)0.3451.08 (0.96 to 1.21)0.214
 >1 h1.13 (0.98 to 1.30)0.0851.14 (0.99 to 1.32)0.0641.12 (0.97 to 1.29)0.1231.11 (0.95 to 1.28)0.181
Insulin resistanceNapping
 No nap1.01.01.01.0
 ≤1 h1.22 (1.05 to 1.42)0.012§1.21 (1.04 to 1.41)0.016§1.22 (1.05 to 1.43)0.011§1.55 (1.30 to 1.85)<0.001§
 >1 h1.33 (1.10 to 1.61)0.003§1.33 (1.10 to 1.60)0.004§1.37 (1.13 to 1.66)0.001§1.69 (1.35 to 2.12)<0.001§

  • HbA1c, glycated haemoglobin; IGR, impaired glucose regulation.

  • *Adjusted by night-time sleep.

  • †Further adjusted by age and gender.

  • ‡The 11 variables were stepwise entered into the final model by forward conditional method (FBG, hypertension, FHD, dyslipidaemia, smoking status, alcohol status, frequency of snoring, physical activity, education levels, BMI and WHR): for the final model for HbA1C, the following eight variables were included FBG, hypertension, dyslipidaemia, smoking status, alcohol status, education level, BMI and WHR; for the final model for IGR, the following nine variables were included, hypertension, FDH, dyslipidaemia, smoking status, alcohol status, snoring, education level, BMI and WHR, where FBG was excluded since it is part of the definition of IGR; for the final model for IR, the following six variables were included, FBG, hypertension, dyslipidaemia and alcohol status.

  • §p<0.05 indicated a significant association with the independent variable.