Table 5. Results of multivariate linear regression analysis^†.

Predictive parameter	Regression coefficient		P-value
	Value	95% CI
6MWD	–0.001	–0.002-0.000	0.004
FEV1, % predicted	–0.007	–0.011-0.002	0.007
Systemic hypertension	0.216	0.009-0.422	0.041

CI, confidence interval; 6MWD, 6 minute walk distance; FEV1, forced expiratory volume in 1 second. ^†, with log C-reactive protein as the dependent variable, and independent variables as age (x₁), gender (x₂), smoking status (x₃), packyears of smoking (x₄), biomass exposure (x₅), systemic hypertension (x₆), duration of COPD (x₇), use of inhaled corticosteroids (x₈), arterial oxygen saturation (x₉), sistolic pulmonary arterial pressure (x₁₀), white blood cell count (x₁₁), FEV1%predicted (x₁₄), modified Medical Research Council score (x₁₅), 6MWD (x₁₆) and body mass index (x₁₇).