Alterations of pulmonary function in patients with inflammatory bowel diseases

AIM: The aim of this study was to investigate the alterations of pulmonary function tests (PFTs) and their relationship with disease activity in inflammatory bowel diseases (IBDs). METHODS: Sixty-four IBD patients (31 Crohn's disease [CD] and 33 ulcerative colitis [UC]) and thirty healthy individuals (controls) were studied with regard to the following parameters of PFTs: Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), their ratio, mid-forced expiratory flow of 25–75% (FEF 25–75), residual volume, total lung capacity, and diffusing capacity of the lung for carbon monoxide (DLCO). The disease activity was calculated using the Crohn's Disease Activity Index for CD and Mayo Clinic Score for UC. Correlation analysis was performed between disease activity and sputum cytology and PFTs. RESULTS: Nineteen of the 31 CD patients (61.29%) and 17 of the 33 UC patients (51.52%) but none of the controls showed at least one abnormal PFTs (P < 0.05). Compared with controls, both CD and UC patients exhibited a significant reduction in FEV1 (P < 0.05), FVC (P < 0.05), FEF 25–75 (P < 0.05), and DLCO (P < 0.05). The majority with decreased measurements of PFTs were in the active phase of diseases (P < 0.05). IBD activity scores correlated negatively with some parameters of PFTs and positively with lymphocytosis and eosinophilia of sputum (P < 0.05). CONCLUSIONS: Pulmonary function disorders are significantly common in IBD patients. The impairment in active disease is significantly greater than in remission.