Table 2.
Multivariate Cox Regression Analysis Exploring the Association of HbA1c Levels with the Risk of the Next Severe Exacerbation of COPD
| HR | 95% CI | P value | |
|---|---|---|---|
| HbA1c level | |||
| Low (<5.7%) | Reference | ||
| Moderate (5.7–6.4%) | 2.19 | 1.39–3.46 | <0.01 |
| High (≥6.5%) | 2.74 | 1.70–4.41 | <0.01 |
| Age | 1.00 | 0.99–1.02 | 0.57 |
| Gender | |||
| Male | Reference | ||
| Female | 1.20 | 0.80–1.80 | 0.38 |
| BMI | 0.94 | 0.87–1.02 | 0.13 |
| Smoking status | |||
| Never-smoker | Reference | ||
| Ex-smoker | 1.18 | 0.78–1.78 | 0.43 |
| Smoker | 1.09 | 0.66–1.81 | 0.73 |
| Disease duration of COPD, years | |||
| <3 | Reference | ||
| 3–5 | 1.17 | 0.79–1.74 | 0.42 |
| >5 | 0.94 | 0.59–1.48 | 0.78 |
| Frequency of hospitalization due to AECOPD in the past 12 months | |||
| <2 | Reference | ||
| ≥2 | 3.42 | 2.43–4.82 | <0.01 |
| GOLD stage | |||
| Stage 1 | Reference | ||
| Stage 2 | 1.19 | 0.56–2.52 | 0.65 |
| Stage 3 | 0.90 | 0.44–1.84 | 0.77 |
| Stage 4 | 0.79 | 0.36–1.71 | 0.54 |
| CAT score | |||
| 0–10 | Reference | ||
| 11–20 | 0.83 | 0.48–1.43 | 0.50 |
| 21–30 | 0.82 | 0.46–1.46 | 0.50 |
| 31–40 | 0.73 | 0.29–1.81 | 0.50 |
| Corticosteroids use | 1.13 | 0.73–1.77 | 0.59 |
| Comorbidity | |||
| Hypertension | 1.13 | 0.80–1.61 | 0.50 |
| Cardiovascular diseases | 1.10 | 0.77–1.57 | 0.60 |
Abbreviations: BMI, body mass index; HbA1c, Hemoglobin A1C; COPD, chronic obstructive pulmonary disease; AECOPD, Acute Exacerbation of COPD; GOLD, Global Initiative for Chronic Obstructive Lung Disease; CAT, COPD assessment test.