Lower detection thresholds for the AAT and CRP assays were 0.21 g/l and 0.1 mg/l, respectively. Genotyping Genotyping of selleck chem inhibitor SERPINA1 PiS (rs17580) and PiZ (rs28929474) polymorphisms was carried out using 5�� nuclease fluorescent real-time PCR (TaqMan Probes technology) on LightCycler480 (Roche) as described before [4]. Probes and primers are given in Table S4. Genotype distributions for PiS and PiZ were both in Hardy Weinberg equilibrium (p=0.93, N=6050, and p=0.99, N=6051, respectively). Statistical Analysis Statistical tests to evaluate differences in the characteristics among the different groups of genotype carriers encompassed Pearson’s ��2 for testing equal proportions, analysis of variance (ANOVA) for testing equal means of normally distributed continuous data, and Kruskal-Wallis for testing equal distributions of continuous data which were not normally distributed.

Main effects of SERPINA1 alleles on lung function decline were assessed using multiple unconditional linear regression models adjusted for sex, age, recruiting area, smoking history (packyears at baseline and between baseline and follow-up), height, baseline BMI and BMI change between baseline and follow-up. Age and packyears between baseline and follow-up were modeled with linear and squared terms to better fit to spirometry data. Interactions between genotypes and other covariates were tested by integrating multiplicative terms in the regression models. Two-sided p-values of <0.05 (and of <0.10 for interactions) were considered as statistically significant.

We performed 56 different linear regression tests (4 respiratory outcomes * 2 genotype comparisons * 7 categories). Bonferroni correction would thus lower the significance threshold to p=0.05/56=0.001. However, since all analyses were hypothesis-driven and most tests not independent of each other, we decided to give the results uncorrected for multiple testing. Logistic regression models were used to compare the odds of developing airflow obstruction or respiratory symptoms between baseline and follow-up among the SERPINA1 genotype classes. The models were adjusted for the same covariates mentioned above. All statistical analyses were performed with STATA, release 10.1 IC (STATA corporation, USA). Supporting Information Table S1 Sensitivity analyses for adjusted mean values in ��(FEV1/FVC) and ��FEF25-75% over 11 years of follow-up comparing different SERPINA1 genotypes.

(PDF) Click here for additional data file.(247K, pdf) Table S2 Adjusted mean values in �� (FEF25-75%/FVC) over 11 years of follow-up comparing different SERPINA1 genotypes. (PDF) Click here for additional data file.(217K, pdf) Table S3 Adjusted mean values in lung function change over 11 years of follow-up comparing GSK-3 different SERPINA1 genotypes in unweighted and weighted models.