[Serum retinol and retinol binding protein-4 levels in patients with chronic obstructive pulmonary disease and their relationship to nutritional status.].

Objective: To explore the serum retinol and retinol binding protein-4 (RBP(4)) levels in patients with chronic obstructive pulmonary disease (COPD) and to investigate their relationship with the nutritional status.

Methods: The serum retinol level was determined by high-performance liquid chromatography (HPLC) in 110 outpatients with stable COPD during Sept. 2006 to Sept.