Table 8.

Association of the duration of HHHFNC in days with bronchopulmonary dysplasia (BPD) and its severity grades

	OR (95% CI)	P value	Adjusted OR (95% CI) *	P value
BPD incidence rate	1.05 (1.03–1.08)	< 0.01	1.04 (1.01–1.06)	0.01
BPD incidence rate based on severity grades
Grade 1	1.04 (1.02–1.06)	< 0.01	1.05 (1.02–1.07)	< 0.01
Grade 2	1.03 (1.00–1.06)	0.02	0.98 (0.94–1.02)	0.33
Grade 3	0.99 (0.96–1.03)	0.67	0.99 (0.95–1.04)	0.71

* Adjusted for sex, gestational age, Apgar score at 1 min, Apgar score at 5 min, receiving surfactant therapy, receiving postnatal steroid therapy, length of hospital stay, duration of mechanical ventilation in days, and use of a low-flow nasal cannula