Differences in serum SP-D levels between German and Japanese subjects are associated with SFTPDgene polymorphisms

Table 1 Characteristics of study subjects

	German	Japanese	pvalue
Patients with IIPs
Number of the subjects	138	94
Age (years)	67.4 ± 0.8	68.0 ± 1.0	0.982
Gender (male/female)	88 (63.8%)/50 (36.2%)	64 (68.1%)/30 (31.9%)	0.497
Smoking (Cu/Ex/Non/ND)	14 (10.1%)/54 (39.1%)/	11 (11.7%)/46 (49.0%)/	0.297
Smoking (Cu/Ex/Non/ND)	64 (46.4%)/6 (4.4%)	35 (37.2%)/2 (2.1%)
VC (percent predicted)	66.1 ± 1.6	70.3 ± 2.2	0.163
DL_CO (percent predicted)	47.7 ± 1.6	44.8 ± 1.8	0.255
Diagnostic category (IPF/NSIP)	94 (68.1%)/44 (31.9%)	61 (64.9%)/33 (35.1%)	0.609
Healthy subjects
Number of the subjects	165	275
Age (years)	36.5 ± 0.9	49.8 ± 0.4	< 0.001
Gender (male/female)	60 (36.4%)/105 (63.6%)	227 (82.5%)/48 (17.5%)	< 0.001
Smoking (Cu/Ex/Non/ND)	41 (24.8%)/20 (12.1%)/	82 (29.8%)/62 (22.6%)/	0.026
	90 (54.6%)/14 (8.5%)	131 (47.6%)/0 (0.0%)

Data are shown as mean ± SEM.
Statistical significance was tested by Mann–Whitney U-test or Chi-square test.
Cu, Current smoker; Ex, Ex-smoker; Non, Non-smoker; ND, No data; IIPs, Idiopathic interstitial pneumonias; VC, Vital capacity; DL _CO, Diffusing capacity of the lung for carbon monoxide; IPF, Idiopathic pulmonary fibrosis; NSIP, Nonspecific interstitial pneumonia.

ISSN: 1471-2350