Vitamin E and Its Effect on Chronic Lung Disease

Summary
An imbalance between oxidants and antioxidants in the lungs could be related to an increased risk of chronic obstructive pulmonary disease (COPD), in which there is increasing blockage to airflow to the lungs. One of the main causes of COPD is smoking. The relationship between COPD and antioxidant imbalance is also supported by a few previous studies. In this study–a randomized and placebo-controlled trial involving women volunteers–treatment with a specific amount of vitamin E, an antioxidant, resulted in the reduction of risk of acquiring COPD by 10 percent in women.

Introduction
The prevalence of COPD in the U.S. adult population is 3 to 4 percent and worldwide that number goes as high as 10 percent. Chronic obstructive pulmonary disease is associated with smoking, obesity, environmental factors, etc. A few previous studies reported the association of dietary habits with lung functioning. A lower blood level of vitamin E was observed in patients with COPD. However, most of these studies were biased and had mixed results. This study is designed as a randomized and blinded study to prevent errors and biases. The study authors wanted to check the effect of 600 IU of vitamin E supplements in women with respect to lung disease.

Methodology
•           Over 39,000 female health professionals over 45 years of age were selected as subjects for this study, and were randomly divided into a control group and a test group.
•           The control group received placebos while the test group received 600 IU of vitamin E every other day for the next ten years.
•           After they filled in initial questionnaires gathering information about their lifestyles, health profiles, etc., they were followed-up every year for ten years.
•           Lung disorders were confirmed by questionnaires, statistical analyses performed and the results analyzed.

Results
•           In the group that received only a placebo treatment, 846 people succumbed to lung disorders, whereas in that where the women received vitamin E supplementation, there were only 760 patients of lung disorders seen after ten years. This corresponded to a cumulative incidence of 4.4 percent in the control group and 3.9 percent in the vitamin E group.
•           Thus, there was a 10 percent reduction in the risk of lung disorders in participants who had received vitamin E supplementation.
•           Findings also verified known facts that factors like smoking, old age, obesity, asthma and high blood pressure all contribute to chronic lung disease.

Shortcomings
This study was not designed precisely to test the use of vitamin E in relation to reducing lung disorders; and thus the incidence of lung disease was solely self-reported by the study participants. However, a later validation study suggested that self-reporting by the women health professionals in this study “is likely to have excellent validity.”

Conclusion
This study correlated the supplementation of vitamin E with the reduction in the incidence of COPD. The authors also proposed a theory explaining transport of vitamin E into the lungs by a certain type of cholesterol. Though the advantages of vitamin E have been highlighted in this study, potential ill-effects of the same vitamin are its role in causing strokes and bleeding in the brain. Thus, necessary vitamin E supplementation must be weighed against the risks, and each individual must be assessed prior to initiation of therapy. With very few prevention protocols for lung diseases, further study of vitamin E could be useful.

For More Information:
Randomised Vitamin E Supplementation and Risk of Chronic Lung Disease in the Women’s Health Study
Publication Journal: Thorax, January 2011
By Anne H. Agler; Tobias Kurt; Cornell University, Ithaca, New York; Brigham and Women’s Hospital, Boston, Massachusetts; INSERM Unit-708, Neuroepidemiology, Paris, France; and the University Pierre et Marie Curie, Paris, France

*FYI Living Lab Reports Are Summaries of the Original Research.