Table 4: Patient profile: smokers versus nonsmokers*.

FeatureSmokerNonsmokerP OR (95% CI)

Patients, (%)43/120 (35.8)77/120 (64.1)<0.01n/a
 Cases, (%)32/43 (74.4)28/77 (36.4)<0.012.04 (1.45–2.88)
 Controls, (%)11/43 (25.6)49/77 (63.6)<0.010.40 (0.23–0.68)
Age, mean years48.4935.23<0.01n/a
Weight, mean kg41.7443.430.46n/a
Male sex, (%)34/43 (79.1)34/77 (50)<0.010.20 (0.08–0.49)
Bilateral lung involvement, (%)18/43 (41.9)20/77 (26)0.070.48 (0.22–1.07)
Pulmonary fibrosis, (%)12/43 (27.9)15/77 (19.5)0.281.60 (0.66–3.83)
Type II respiratory failure, (%)10/43 (23.3)9/77 (11.7)0.092.29 (0.84–6.17)
Duration of hospital stay, mean days8.813.40.02n/a
TLC ×109/L, mean11.79.90.12n/a
 Neutrophils, mean %84.078.10.02n/a
Serum protein U/L, mean5.096.11<0.01n/a

OR: odds ratio; CI: confidence interval; TLC: total leukocyte count; n/a: not applicable.