Hitoshi Saito, Koichiro Nomura, Shinji Abe, Takashi Motegi, Takeo Ishii, Kumiko Hattori, Yuji Kusunoki, Akihiko Gemma, Kozui Kida

Comorbidities are characteristic of COPD. However, little is known about the secondary manifestations of COPD in the gastrointestinal tract. Therefore, we aimed to explore the long-term effects of gastrectomy in patients with spirometry-defined COPD or those at risk of COPD. Subjects included 87 patients either with COPD or at risk of COPD (symptomatic) who underwent gastrectomy between December 2003 and October 2013 (group A), and 174 patients either with COPD or at risk of COPD, matched by age (±5 years), sex, and forced expiratory volume in 1 second (FEV1) as percentage of predicted (FEV1% predicted) (±5%) (group B). All patients underwent routine blood chemistry and pulmonary function tests, arterial blood gas analysis, 6-minute walk test (6MWT), high-resolution chest computed tomography scans, and nutritional assessments. The mean duration postgastrectomy was 18.3±15.4 years. The mean FEV1 and FEV1% predicted were 2.07±0.76 L and 74.6±24.5%, respectively. Univariate analysis indicated that group A patients had significantly lower body mass index, fat-free mass index, and serum hemoglobin and albumin concentration (all P=0.00), and walked a significantly shorter distance in the 6MWT (P<0.05). Multivariate linear regression analysis for the distance in the 6MWT indicated that increased residual volume (RV) to total lung capacity (TLC) as percentage of predicted (%RV/TLC) alone was an independent and significant predictor of reduced distances in the 6MWT. We concluded that nutritional insufficiency in patients with COPD (or those at risk of COPD) who previously underwent gastrectomy might lead to hyperinflation and consequently, decreased exercise capacity.