Disease Markers

Research Article

Plasma Cathepsin S and Cathepsin S/Cystatin C Ratios Are Potential Biomarkers for COPD

Table 3

Logistic regression analysis for severe airflow limitation (% FEV₁ predicted < 50).


	⁢Cathepsin S and % FEV₁predicted < 50				Cat S/Cys C (/10³) and % FEV₁ predicted < 50
			OR	95% CI			OR	95% CI

Cat S (10 increments)	7.82		0.32	0.14–0.71	—	—	—	—
Cat S/Cys C (/10³)	—	—	—	—	5.19		0.87	0.77–0.98
Age (10 increments)	12.14		3.82	1.80–8.12	10.76		3.02	1.56–5.84
BMI	2.28	0.13	0.90	0.79–1.03	2.77	0.10	0.89	0.77–1.02
PY (10 increments)	2.46	0.12	1.11	0.97–1.27	1.21	0.27	1.07	0.95–1.22
Serum Cr	5.05		0.02	0.001–0.60	6.35		0.014	0.0005–0.39
Male	3.35	0.07	11.93	0.84–169.5	4.10		15.13	1.09–209.5
Ex-smoker	1.44	0.23	1.88	0.67–5.28	2.97	0.09	2.45	0.88–6.79
HT (−)	2.18	0.14	0.40	0.12–1.35	2.09	0.15	0.42	0.13–1.36
ICS (−)	0.001	0.97	1.03	0.26–4.07	0.044	0.83	0.87	0.23–3.23

; . FEV₁: forced expiratory volume in 1 second; Cat: cathepsin; Cys: cystatin; OR: odds ratio; CI: confidence interval; BMI: body mass index; PY: pack-years; Cr: creatinine; HT: hypertension; ICS: inhaled corticosteroid.