Table 2.

Association between presence of AL and medical history

Explanatory variable	Unadjusted		Adjusteda
	OR (95% CI)	P-value	OR (95% CI)	P-value
Sex
Female	0.38 (0.34–0.42)	<0.0001	0.59 (0.52–0.67)	<0.0001
Male	Reference		Reference
Age (10-year age increase)	1.95 (1.87–2.03)	<0.0001	1.99 (1.90–2.09)	<0.0001
BMI (1 kg/m2 increase)	0.98 (0.97–0.99)	0.0006	0.96 (0.95–0.98)	<0.0001
Smoking history (pack-years)
0–14	Reference		Reference
15–24	1.81 (1.52–2.16)	<0.0001	1.78 (1.46–2.17)	<0.0001
25–49	3.60 (3.20–4.06)	<0.0001	2.60 (2.24–3.00)	<0.0001
≥50	6.88 (6.04–7.84)	<0.0001	3.69 (3.15–4.33)	<0.0001
Unknown	2.57 (1.75–3.77)	<0.0001	1.92 (1.28–2.88)	0.0017
Medical history
Pulmonary tuberculosis
No	Reference		Reference
Yes	2.82 (2.35–3.38)	<0.0001	1.72 (1.39–2.11)	<0.0001
Primary lung cancer
No	Reference		Reference
Yes	2.85 (2.47–3.28)	<0.0001	1.50 (1.28–1.77)	<0.0001
Myocardial infarction
No	Reference		Reference
Yes	2.02 (1.70–2.40)	<0.0001	1.22 (1.01–1.48)	0.0399
Other heart diseases
No	Reference		Reference
Yes	2.04 (1.80–2.31)	<0.0001	1.36 (1.18–1.56)	<0.0001

Note:

^aModel was adjusted for age, sex, BMI and smoking history.

Abbreviations: AL, airflow limitation; OR, odds ratio; CI, confidence interval; BMI, body mass index.