Multiple linear regression of the level of three inflammatory markers in chronic obstructive pulmonary disease
| CRP | sTNFR-1 | OPG | |
| Subjects n | 404 | 401 | 402 |
| GOLD category | |||
| II (FEV1 50–80) | 0 | 0 | |
| III (FEV1 30–50) | -43.73(-90.5–3.1) | 530.5*(76.9–984.0) | |
| IV (FEV1 0–30) | -91.45*(-167.9– -15.0) | 536.2(-196.3–1268.8) | |
| Experienced ≥2 exacerbations last year | |||
| No | 1 | 0 | 0 |
| Yes | 1.44*(1.02–2.04) | 53.41(-7.2–114.0) | 652.6*(69.8–1235.3) |
| Chronic cough | |||
| No | 1 | ||
| Yes | 0.67*(0.49–0.91) | ||
| Comorbid heart disease# | |||
| No | 0 | ||
| Yes | 57.49(-3.2–118.2) | ||
| Medically treated hypertension | |||
| No | 0 | ||
| Yes | 98.8*(46.9–150.7) | ||
| Depression needing medical treatment | |||
| Never | 0 | ||
| Currently | 81.53*(16.6–146.5) | ||
| Previously | 69.46*(3.7–135.3) |
Data are presented as coefficient (95% confidence interval), unless otherwise stated. Due to the skewed distribution of C-reactive protein (CRP), the outcome variable was log transformed, and the geometric mean ratios are shown. The reference values are thus 1 for each category and not 0 as for the other nontransformed markers. All models include adjustment for sex, age, body composition, smoking habits and use of inhaled steroids and/or platelet inhibitors. sTNFR-1: soluble tumour necrosis factor receptor-1; OPG: osteoprotegrin; GOLD: Global Initiative for Chronic Obstructive Lung Disease; FEV1: forced expiratory volume in 1 s. #: either known heart failure or coronary heart disease. *: p<0.05.