Small intestinal absorption in patients with chronic obstructive pulmonary disease complicated by cor pulmonale - A pilot study.

ABSTRACT

BACKGROUND: Cor pulmonale is a common complication to Chronic Obstructive Pulmonary Disease (COPD), and may result in increased pressure in the inferior caval vein and stasis of the liver. The chronic pulmonary hypertension may lead to stasis in the veins from the small intestine and thereby compromise absorption of nutrients. AIM: To investigate whether patients with pulmonary hypertension have reduced absorption capacity compared to COPD patients without cor pulmonale. METHODS: Absorption of d-xylose (25 g) and zinc (132 mg), administered as a single dose, was tested in 14 COPD patients, seven with and seven without cor pulmonale. The presence of cor pulmonale was determined by echocardiography. The concentration of d-xylose and zinc were measured in peripheral blood one, two and three hours after ingestion and used as markers of absorption. Furthermore, urine was collected for five hours to determine the amount of excreted d-xylose. RESULTS: No significant difference in absorption of d-xylose (p = 0.28) or zinc (p = 0.51) was found between the two groups. However, a trend towards a delay in d-xylose absorption, as assessed by time-to-peak concentration, was observed in patients with cor pulmonale (p = 0.08). There was no significant difference in the amount of excreted d-xylose in the urine between the groups (p = 0.52). No correlation was found between the tricuspid regurgitation gradient and the absorption of both test-markers (rs = 0.34 and rs = -0.25). Likewise, no correlations were found between the inferior caval pressure during the in- and expiration phases and the absorption of d-xylose (rs = -0.09 rs = 0.23) or zinc (rs = -0.39, rs = -0.39). CONCLUSION: We found no indications that small intestinal absorption is affected in a clinically relevant degree in patients with cor pulmonale.