• Intervention
    What effect does the consumption of milk and milk products have on mucus production for patients with COPD?
    • Conclusion

      Authors of a narrative review published in 2005 of 49 references concluded that while some people may perceive some aspects of mucus production after consuming milk and milk products (either cow's or soy), there is no significant effect of milk and milk product consumption on mucus production or various lung function parameters.  Further research on milk and milk product consumption on mucus production in people with COPD is needed. 

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What effect does consumption of omega-3 fatty acids have on patients with COPD?
    • Conclusion

      Six studies regarding the consumption of omega-3 fatty acids and COPD were reviewed.  One randomized trial reports improvements in subjects with COPD after consuming an omega-3 fatty acid-rich supplement.  Five epidemiological studies report inconsistent findings regarding a relationship between overall fish intake and COPD mortality, pulmonary function, and symptoms.  Further research on the consumption of fatty acids and COPD is needed.        

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What relationship do antioxidants, such as vitamins A, C and E and flavonoids, have on pathogenesis and/or exacerbations in patients with COPD?
    • Conclusion

      Eight studies regarding the relationship between antioxidants and COPD were reviewed.  Six studies report reduced serum and/or tissue levels of vitamins A, C and/or E in people with COPD.  Three studies regarding supplementation report insignificant effects, however these studies were limited in scope, duration and power.  Further research on the relationship between antioxidants and COPD is needed.   

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What effect does nutritional supplementation have on patients with COPD?
    • Conclusion

      In the inpatient setting, nutritional supplementation for 7 - 12 days results in increased energy intake and weight maintenance as nutritional needs may be higher during hospitalization.  In the outpatient setting, nutritional supplementation results in increased energy intake, with weight gain more likely when combined with exercise. Authors of a Cochrane review published in 2005 of 12 studies concluded that nutritional supplementation for greater than 2 weeks had no significant effect on anthropometric measures, lung function or exercise capacity in patients with stable COPD. Three studies report conflicting findings regarding the effect of macronutrient composition of supplementation on lung function.  Further research on the effect of nutritional supplementation and macronutrient composition in people with COPD is needed.        

    • Grade: II
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What is the evidence for use of supplemental oxygen in people with COPD?
    • Conclusion

      Authors of a Cochrane review published in 2005 of 31 studies concluded that ambulatory oxygen, defined as the use of supplemental oxygen during exercise and the activities of daily living, improves exercise performance in people with moderate to severe COPD.  Research regarding the effect of supplemental oxygen on food intake and nutritional status is needed.

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.