Comparison of baseline characteristics between patients with normal and higher IgG titer against Porphyromonas gingivalis.

High-IgG titer group includes subjects whose titers against Porphyromonas gingivalis (PgFDC381 and/or PgSu63) are above mean+2SD of healthy subsets [20].“Frequent exacerbations” are defined as ≥2 exacerbations per year.FEV1, forced expiratory volume in one second; GOLD, Global Initiative for Chronic Obstructive Lung Disease.; MRC, British Medical Research Council. Data are expressed as medians (25th–75th percentiles).