Effects of Dietary Supplements on Response to Air Pollution
Condition: Inflammation
MeSH terms: Inflammation
Study type: Interventional

Summary: 
      This study will determine if a comprehensive antioxidant/anti-inflammatory dietary supplement
      pack can offer protection against a decline in lung function and increase in inflammation and
      oxidative stress following acute exposure to particulate matter air pollution with a diameter
      <2.5 µm (PM2.5).

      The investigators hypothesis is a follows: Compared to an appropriate control,
      supplementation with a comprehensive antioxidant/anti-inflammatory dietary supplement pack
      for 18 weeks will: 1) reduce the decline in lung function following acute exposure to
      naturally occurring elevations in PM2.5 levels as measured by exhaled nitric oxide levels and
      forced vital lung capacity; and 2) reduce changes in pro-inflammatory cytokines following
      acute exposure to naturally occurring elevations in PM2.5 levels as measured by plasma levels
      of C-reactive protein.
    

Detailed description: 
      The study will be conducted in Cache County, UT. Surrounded by tall mountains (2513-3042 m),
      and subject to frequent winter atmospheric inversions characterized by stagnant air that
      traps and concentrates pollutants, Cache Valley, home to 120,000 inhabitants, is particularly
      susceptible to high particulate air pollution during the winter months.

      A total of 70 individuals (with the goal of completing 60) between the ages of 45-80 will be
      recruited from Cache County, UT. Eligible participants will be randomly assigned to one of
      two treatment arms (Placebo Dietary Supplements, Active Dietary Supplements) in a manner to
      provide balanced assignment between the two arms with respect to age, sex and baseline
      exhaled nitric oxide levels.

      Participants assigned to the Placebo or Active arms will be provided with sealed envelopes or
      bottles containing dietary supplements (or matched placebos) along with instructions as to
      when to consume the supplements. Participants will be instructed to consume their supplements
      twice a day with meals containing a small amount of fat (at least 3 grams) in order to
      optimize the absorption of fat soluble nutrients. They will also be instructed to consume the
      supplements with liquids in order to enhance absorption and to minimize GI upset and choking
      potential. Participants will be asked to maintain their typical diet for the 18 weeks of the
      study.

      Routine Clinic Visits are scheduled at two week intervals for the length of the study (with
      accommodations made for Holiday schedules). During these visits, participants will: 1)
      receive a sufficient supply of supplements to last until the next routine clinic visit; 2)
      return any unused supplements; 3) be provided an opportunity to describe any adverse
      events/reactions to the supplements; 4) describe any health issues experienced since the
      previous exam; and 5) have their weight and blood pressure assessed.

      Endpoint Clinic Visits are scheduled to coincide with low and high PM2.5 exposure. Starting
      on Jan 2, participants will be notified of a potential endpoint assessment day when the PM2.5
      levels are predicted by the Utah Department of Environmental Quality, Division of Air
      Quality, to rise above 30 µg/m3 (peak event) or fall below 8 µg/m3 (baseline event). Endpoint
      visits will take place 24 hrs following these peak and baseline events. Based on historical
      patterns, we anticipate at least three peak events, with corresponding baseline assessments,
      during the intervention time period. For purposes of analysis, each peak event will be paired
      with the nearest baseline event so that both events are captured at a similar time after
      initiation of the intervention.

      At each endpoint clinic visit, participants will undergo assessments of lung function and
      systemic inflammation. Blood samples will be obtained for potential future analysis of
      additional markers of systemic inflammation and plasma antioxidant capacity.
    

Intervention name(s): Placebo; Antioxidant, anti-inflammatory dietary supplement
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): 7-pill placebo dietary packed visually identical to active dietary supplement; A combination of dietary supplements including: β-carotene, vitamin C, vitamin D3, vitamin E, vitamin K, thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, biotin, pantothenic acid, calcium, iodine, magnesium, zinc, selenium, copper, manganese, chromium, molybdenum, boron, silicon, vanadium, eicosapentaenoic acid, docosahexaenoic acid, olive extract, mixed tocopherols, bioflavonoids, inositol, choline, N-acetyl L-cysteine, bromelain, coenzyme Q10, turmeric extract, lutein, lycopene, broccoli concentrate, grape seed extract
Other intervention name(s): USANA Mega Antioxidant; USANA Chelated Mineral; USANA Proflavanol C 200; USANA Vitamin D
Intervention MeSH terms: Vitamin D; Anti-Inflammatory Agents; Antioxidants
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: Antioxidants; Dietary supplements; Forced vital lung capacity; Exhaled nitric oxide; Air pollution