Lung disease burden assessment by oscillometry in a systematically disadvantaged urban population experiencing homelessness or at-risk for homelessness in Ottawa, Canada from a prospective observational study

Table 2 Mean R5-20, Ax and X5 values based on spirometry diagnosis of COPD

	Diagnosis of COPD using the fixed ratio method		Diagnosis of COPD using the LLN method
	COPD	No COPD	COPD	No COPD
R_5–20 (cmH2O.s/L)	1.02^a	0.81^a	1.20^b	0.72^b
A_x (cmH2O/L)	14.8^c	13.0^c	17.7^d	11.2^d
X₅ (cmH2O.s/L)	− 1.43^e	− 1.53^e	− 1.47^f	− 1.44^f

Mean oscillometry values are reported for R5–20, Ax and X5 based on the presence of COPD assessed using the fixed ratio method (a post-bronchodilator FEV1/FVC ratio < 0.70) and the LLN method (a post-bronchodilator FEV1/FVC ratio ≤ LLN). R5-20 is a measure of small airway resistance. Ax is a measure of the area under the reactance curve. X5 is a measure of airway elastance. P values were generated using a two-tailed t-test. ^ap = 0.48; ^bp = 0.13; ^cp = 0.70; ^dp = 0.22; ^ep = 0.77; ^fp = 0.92. n = 55

ISSN: 1471-2466