Antioxidant Therapy in Lean and Obese Asthmatics
Condition: Asthma
MeSH terms: Asthma
Study type: Interventional
Phase: Phase 2

Summary: 
      This project will assess the effectiveness of antioxidant supplementation with common
      vitamins A, C, E and selenium in controlling asthma symptoms among lean and obese asthmatics.
      This project may improve our ability to treat asthma and our understanding of the link
      between nutritional antioxidants and asthma.
    

Detailed description: 
      Asthma & Obesity are both growing public health crises that also may be critically
      interrelated for many patients. Obesity increases the risk for asthma in both adults and
      children, and obesity increases the severity of existing asthma. Obesity leads to increased
      systemic oxidative stress, however little is know about obesity-related oxidative stress
      within the airway. Since oxidative stress contributes to the pathogenesis of asthma, obesity
      may influence asthma risk and severity through this mechanism. Asthmatics have low serum
      antioxidant activity. There is conflicting evidence about whether or not antioxidant
      supplementation reduces asthma severity. This may be related to asthma's heterogeneous
      nature. Antioxidant supplementation may be effective in select subgroups that have the
      greater oxidative stress, such as asthmatics with occupational exposures or obesity. In fact,
      the evidence supporting antioxidant supplementation in asthma involved subjects with
      oxidant-related triggers. We hypothesize that obesity-related oxidant stress puts asthmatics
      at risk for increased airway oxidative stress and greater asthma severity. We hypothesize
      that supplementation with common antioxidants will significantly reduce airway inflammation
      and oxidative stress, and lead to improved pulmonary function and daily asthma control. This
      pilot study is designed as a randomized, double-blinded, placebo-controlled, parallel
      intervention trial involving lean and obese adolescents and young adults with asthma. After
      the 2-week run-in period, all subjects will undergo baseline testing (see figure 1). At
      randomization they will receive either placebo or a multivitamin antioxidant for 42 days. At
      the end of the 42 day intervention all subjects will undergo final testing. Primary
      Hypothesis: In young asthmatics, antioxidant supplementation increases plasma and airway
      antioxidant levels leading to improved lung function and asthma control. Secondary
      Hypotheses: 1) Obesity-related systemic oxidant stress is associated with increased oxidative
      stress within the airway. 2) Antioxidant supplementation will lead to greater improvements in
      asthma control among obese compared to lean (not underweight) asthmatics. 3) Antioxidant
      supplementation will lead to greater improvements in airway markers of inflammation and
      oxidative stress among obese compared to lean asthmatics. We will assess asthma control and
      lung function before and after therapy.
    

Intervention name(s): Vitamins A, E, C & Selenium; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): daily dose = Vitamin A 10000 IU (beta carotene), Vitamin E 400 IU, Vitamin C 1200mg, and Selenium 300mcg.; total daily dose = 1200mg whey protein, 800mg microcrystalline cellulose
Intervention MeSH terms: Vitamin A; Selenium
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: asthma; obesity; nutrition; antioxidant