The relationship between pulmonary function and red cell distribution width in general population

Abstract Background: The role of nutrition on pulmonary function and also the effect of micro-nutrients on red blood cell distribution width have been documented. Objective: To determine the relationship between the lung function tests and RBC distribution width (RDW) in general population with no history of pulmonary diseases. Methods: This was a cross-sectional study conducted on general population of Qazvin (Iran) in 2005. A total of 160 persons from both genders aged 14 to 73 years with no respiratory disease were randomly selected. Pulmonary function was assessed using the data obtained from FEV1, and FVC by spirometry, body weight, height, total pack-years of smoking, hemoglobin concentration, and hematological indices. The data were analyzed using a linear regression model and coefficient of variation to identify the relationship between the lung volumes and hematological indices, especially the RDW. Findings: A direct relationship was found between the RDW and the pack years of smoking but with no significant difference, statistically. However, a weak and inverse relationship between both FEV1 and FVC and RDW was observed in which the difference found to be statistically significant. Also, a direct relationship between FEV1 and height and an inverse relationship between FEV1 and pack-years of smoking was demonstrated. Furthermore, the mean hematological indices of study population were identified. Conclusion: Demonstration of an inverse relationship between RDW and pulmonary function is supporting of our hypothesis and raises the possibility by which the RDW may be considered as a biomarker for nutrients affecting pulmonary function. A possible reaction to the weak relationship found in our study might be attributed to the presence of confounding factors and probably the small number of participants took part in our research project.