Unique features of non-obstructive emphysema and pure airway obstruction.

Abstract

SETTING: Emphysema without airway obstruction or airway obstruction without

emphysema are often detected clinically, although they are commonly co-existent.

We therefore tested the hypothesis that non-obstructive emphysema and pure airway

obstruction have unique features. METHODS: A case-control observation study was

undertaken retrospectively in a patient cohort at a single centre. Among 2662

subjects who underwent chest computed tomography and pulmonary function tests, we

enrolled 90 patients with non-obstructive emphysema, 119 with pure airway

obstruction, 81 with obstructive emphysema and 2031 subjects as normal controls.

The features of the four groups were analysed and compared. RESULTS: Higher serum

homocysteine (13.4 +/- 7.4 vs. 11.6 +/- 4.6 mol/l), higher rate of osteoporosis

(15.8% vs. 4.5%), higher leukocyte count, higher male ratio, lower serum albumin

and lower body mass index were observed in subjects with non-obstructive

emphysema than in controls (P < 0.05). In multiple logistic regression analysis

of groups without airway obstruction, osteoporosis, hyperhomocysteinaemia,

hypoalbuminaemia and higher leukocyte count were independent factors associated

with non-obstructive emphysema (P < 0.05). CONCLUSION: Hyperhomocysteinaemia,

hypoalbuminaemia, osteoporosis and higher leukocyte count were independent

predictors of non-obstructive emphysema.