Abstract: Objective Through determination of levels of VC、FEV1、FEV1/FVC、DLCO and DLCO/VA,to investigate the change of lung function in patients with chronic obstructive pulmonary disease(COPD) Combined with diabetes mellitus(DM).Methods Thirty patients with COPD and thirty eight patients with COPD combined with DM were examined and the thirty eight patients with COPD and DM were further divided into 2 groups,22 with DM complication and 16 without. The levels of VC、FEV1、FEV1/FVC、DLCO and DLCO/VA were determined and analysed.Results The levels of VC、DLCO and DLCO/VA were lower in patients with COPD combined with DM with complications than in those with COPD only(P<0.05).The level of DLCO and DLCO/VA were lower in patients with DM complications than in those without(P<0.05).Conclusion In patients with COPD combined with DM,especially with DM complications restrictive ventilatory and diffusion dysfunctions are more aggravated than in those with COPD only.

Key words: chronic obstructive pulmonary disease, diabetes mellitus, lung function