Table 4. PA/A ratios of ≥1 predict the requirement for advanced treatment in patients hospitalized with acute exacerbation of COPD.

Advanced treatment	OR	95% CI	P value
High-flow nasal cannula
Crude	2.497	1.131–5.513	0.02
Adjustment†	2.382	1.051–5.395	0.03
Adjustment‡	2.359	0.814–6.834	0.11
Non-invasive ventilation
Crude	3.299	1.795–6.065	<0.001
Adjustment†	3.247	1.736–6.074	<0.001
Adjustment‡	4.801	1.977–11.658	0.001
Intubation
Crude	1.869	0.947–3.689	0.07
Adjustment†	2.095	1.043–4.209	0.03
Adjustment‡	2.041	0.757–5.502	0.15

^†, adjusted for age and sex; ^‡, adjusted for age, sex, pack-years, body mass index, hypertension, diabetes, pulmonary tuberculosis, bronchiectasis, ischemic heart disease, atrial fibrillation, chronic kidney disease, previous cerebrovascular disease, forced vital capacity (% pred), forced expiratory volume in 1 second (% pred), diffusion lung capacity of carbon monoxide, global initiative for chronic obstructive lung disease group, white blood cells, hemoglobin, platelets, blood urea nitrogen, creatinine, C-reactive protein, and hypoventilation and ventilation-perfusion mismatch. PA/A ratio, pulmonary artery-to-aorta ratio; COPD, chronic obstructive pulmonary disease; OR, odds ratio; CI, confidence interval.