ascorbic-acid and Bronchitis--Chronic

Oxidative stress plays a key role in the pathogenesis of respiratory diseases; however, studies on antioxidant vitamins and respiratory outcomes have been conflicting. We evaluated whether lower serum levels of vitamins A, C, D, and E are associated with respiratory morbidity and mortality in the U.S. adult population.. We conducted a pooled analysis of data from the 1988-1994 and 1999-2006 National Health and Nutrition Examination Survey (participants aged ≥ 20 years). We estimated covariate-adjusted odds ratios (aOR) per interquartile decrease in each serum vitamin level to quantify associations with respiratory morbidity, and covariate-adjusted hazard ratios (aHR) to quantify associations with respiratory mortality assessed prospectively through 2015. Vitamin supplementation and smoking were evaluated as potential effect modifiers.. Lower serum vitamin C increased the odds of wheeze among all participants (overall aOR: 1.08, 95% CI: 1.01-1.16). Among smokers, lower serum α-tocopherol vitamin E increased the odds of wheeze (aOR: 1.11, 95% CI: 1.04-1.19) and chronic bronchitis/emphysema (aOR: 1.13, 95% CI: 1.03-1.24). Conversely, lower serum γ-tocopherol vitamin E was associated with lower odds of wheeze and chronic bronchitis/emphysema (overall aORs: 0.85, 95% CI: 0.79-0.92 and 0.85, 95% CI: 0.76-0.95, respectively). Lower serum vitamin C was associated with increased chronic lower respiratory disease (CLRD) mortality in all participants (overall aHR: 1.27, 95% CI: 1.07-1.51), whereas lower serum 25-hydroxyvitamin D (25-OHD) tended to increase mortality from CLRD and influenza/pneumonia among smokers (aHR range: 1.33-1.75). Mortality from influenza/ pneumonia increased with decreasing serum vitamin A levels in all participants (overall aHR: 1.21, 95% CI: 0.99-1.48). In pooled analysis, vitamin C deficiency and 25-OHD insufficiency were associated with mortality from influenza/pneumonia, increasing mortality risk up to twofold.. Our analysis of nationally representative data on over 34,000 participants showed that lower serum levels of vitamins A, C, D, and α-tocopherol vitamin E are associated with increased respiratory morbidity and/or mortality in U.S. adults. The results underscore the importance of antioxidant vitamins in respiratory health.

Topics: Adult; alpha-Tocopherol; Antioxidants; Ascorbic Acid; Bronchitis, Chronic; Emphysema; Humans; Influenza, Human; Morbidity; Nutrition Surveys; Vitamin A; Vitamins

N-acetylcysteine (NAC) is known to have direct antioxidant properties due to its thiol-group on the one hand as well as indirect antioxidant capacity as cysteine-donor to cellular glutathione-synthesis on the other hand. Therefore NAC appears to be attractive in antioxidant therapy of inflammatory disorders of the lung. This study aimed to investigate the use of antioxidant therapy with NAC in chronic bronchitis.. In this randomized, double-blinded and placebo-controlled trial 100 patients divided into four groups were observed over a period of 3 months. The treatment consisted of either 600 mg NAC bid, 500 mg Vitamin C bid, a combination of those two substances using the same dosage or a placebo-preparation. The release of reactive oxygen species from isolated neutrophilic granulocytes and mononuclear cells was quantified before treatment and after three months using chemiluminescence (primary outcome parameter). Furthermore cellular glutathione content of these inflammatory cells was quantified spectrometrically. In addition, leukocyte-count and erythrocyte sedimentation rate as well as spirometry and a standardized symptom-based questionnaire were used to monitor the clinical efficacy.. None of the above substances were able to significantly reduce the release of reactive oxygen species from the examined population of inflammatory cells. They also failed to increase intracellular glutathione-levels. Concordantly, no changes in spirometry and the results of the symptom-based questionnaire were found.. In summary NAC, Vitamin C and the NAC/ Vitamin C-combination did neither enhance antioxidant protection in the blood nor is it of any clinical benefit in chronic bronchitis. Possible reasons may be a lack of antioxidant deficiency in these patients and negative feedback mechanisms of the glutathione-system.

Topics: Acetylcysteine; Antioxidants; Ascorbic Acid; Blood Sedimentation; Bronchitis, Chronic; Double-Blind Method; Drug Therapy, Combination; Female; Free Radical Scavengers; Glutathione; Humans; Leukocyte Count; Leukocytes, Mononuclear; Luminescent Measurements; Male; Middle Aged; Neutrophils; Reactive Oxygen Species; Spirometry; Surveys and Questionnaires; Treatment Failure