Serum heme oxygenase-1 as a marker of lung function decline in patients with chronic silicosis

To identify predictive factors of excess decline in forced expiratory volume in one second (FEV1) in patients with chronic silicosis.

Forty-six male patients enrolled in 2004 were screened and received pulmonary function tests.

Among the 33 included patients, 12 were categorized as rapid decliners (reduction in FEV1 > 60 mL/yr). The mean level of serum heme oxygenase-1 (HO-1), a marker of oxidative stress, was significantly lower in rapid decliners than in normal decliners (P = 0.002). Logistic regression analysis revealed that serum HO-1 was a factor affecting clinically important decline in FEV1 (odds ratio = 0.52; 95% confidence interval, 0.31 to 0.88) independent of the effects of age, height, weight, smoking, exposure status, and C-reactive protein.

Serum HO-1 may be a predictor of lung function decline in silicosis patients.