Table 4 The association between diabetes and LOS: Multivariate logistic regression

Diabetes (Yes vs. No)

1.08 (0.90, 1.29)

Smoking

 Non-smoker

Reference

 Current smoker

0.93 (0.80, 1.08)

 Former smoker

1.14 (1.00, 1.30)

 Frequency of hospitalization due to AECOPD in past the 12 months (≥ 2 vs. < 2)

1.28 (1.13, 1.45)

Insurance

 No insurance

Reference

 Medical insurance for urban and rural residents

1.20 (0.81, 1.79)

 Medical insurance for urban workers

1.66 (1.11, 2.48)

 Other Insurance

1.11 (0.71, 1.73)

Cardiovascular comorbidities (Yes vs. No)

1.39 (1.24, 1.56)

Respiratory comorbidities (Yes vs. No)

1.64 (1.45, 1.85)

Digestive comorbidities (Yes vs. No)

1.51 (1.12, 2.04)

CAT score at admission

 0–10

Reference

 11–20

1.04 (0.85, 1.28)

 21–30

1.66 (1.35, 2.03)

 31–40

2.22 (1.67, 2.96)