Lower Lung Capacity Has Link to Antioxidants

VANCOUVER -- Chronic obstructive pulmonary disease (COPD) patients who eat a diet deficient in antioxidants may be putting themselves at risk for worsening lung function, researchers found.

Selenium deficiency predicted poorer forced vital capacity of the lungs overall, Mohammad S. Khan, DO, of Akron City Hospital in Akron, Ohio, and colleagues reported here at the CHEST meeting.

Deficiency of vitamins A, C, and D were all linked to poorer forced vital capacity of the lungs in men, but not women, with COPD in the small, 20-patient dietary intake study.

These results emphasize the need to individualize dietary recommendations for COPD patients, perhaps requiring the input of a registered dietitian, Khan said in an interview.

Malnutrition has long been a known risk of COPD, which, while not well understood, likely stems from the inflammatory state, which causes the body to burn through its caloric and antioxidant supply.

Attempts to intervene by pumping up protein and total calories with various supplements have all failed, co-author Matthew L. Krauza, MD, also of Akron City Hospital, told MedPage Today.

Whether boosting antioxidants would prevent lung function deterioration in COPD has yet to be tested, but it's reasonable to recommend that patients improve their antioxidant intake if they are deficient, Krauza said.

Boosting dietary intake from fruits and vegetables is likely better than relying on antioxidant supplements, which have shown potential for harm in some cases in trials in other areas of medicine.

"We're missing an opportunity whenever we don't refer these patients for nutritional assessment," Krauza said in the interview. "We focus so much on lifestyle intervention with smoking cessation ... but I really don't think we're hitting that nutritional aspect of it as well as we could."

Vitamin deficiency may also be a way to pick out patients predisposed to shed pounds who need nutritional intervention to prevent weight loss, which has been linked to elevated mortality risk in COPD, commented Brian W. Carlin, MD, of Allegheny General Hospital in Pittsburgh and chair of the COPD Alliance.

The researchers looked at intake of foods on food frequency questionnaires completed by 20 patients -- 13 women and seven men -- in a larger trial of functional status in COPD with different portable oxygen delivery methods.

Overall, vitamin deficiency determined from food intake was common, at rates of 55% for vitamin A, 45% for vitamin C, 70% for vitamin D, and 90% for vitamin E.

Selenium deficiency appeared in 25% of the cohort, and was linked to lower forced vital capacity in the overall cohort compared with nondeficiency.

Gender appeared to play a role in the effect of deficiency with interactions for vitamin A (P=0.0053), vitamin C (P=0.0391), and vitamin D (P=0.0391).

Deficiency predicted poorer lung capacity in men for vitamin A (P=0.0044), vitamin C (P=0.0048), and vitamin D (P=0.028). Forced vital capacity was consistently lower for women, with no difference between those who were deficient and those who were not.

An antioxidant impact may have been easier to detect in men because of women's poorer lung function at baseline and decreased forced vital capacity due to their smaller physical size, the researchers noted.

However, a real gender difference is plausible as well because of greater lifestyle risks in men, a modulating effect of sex hormones that varies between the sexes, or different dietary requirements between them, they added.

The researchers cautioned that their study was limited by the small sample size of patients and use of one-time, self-reported dietary intake rather than directly measured antioxidant status.

http://www.medpagetoday.com/MeetingCoverage/CHEST/23160

Thought you might find this interesting,I did.

(if this is a repeat post, please forgive, I didnt see it)

Hope your all well, breathing easy and enjoying your day.

Love Always

Holly