Effects of Dietary Supplements on Response to Air Pollution

Inflammation Clinical Trial

Official title:

Effect of an Antioxidant and Anti-inflammatory Dietary Supplement Pack on the Adverse Physiological Actions Associated With Acute PM2.5 Exposure

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01488656
• Other study ID #: USU #4001
• Secondary ID: 4011
• Status: Completed
• Phase: N/A
• First received: December 6, 2011
• Last updated: August 14, 2012
• Start date: November 2011
• Est. completion date: June 2012

Study information

• Verified date: August 2012
• Source: Utah State University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 66
• Est. completion date: June 2012
• Est. primary completion date: March 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 45 Years to 80 Years

Eligibility

Inclusion Criteria:

• Male or female of any race or ethnicity

• Body Mass Index (BMI) between 19 - 34 kg/m2

• Non-smoking status

• Willing to consume assigned dietary supplements for 18 weeks.

Exclusion Criteria:

• BMI <19 or >34 kg/m2

• Uncontrolled hypertension defined as diastolic blood pressure >=95 mm Hg or systolic blood pressure >=160 mm Hg

• Documented presence of atherosclerotic disease and/or cardiopulmonary disease

• History of frequent falls

• History of drug or alcohol abuse

• History of unstable depression or mental illness within the last 6 months for which the PI believes could impact the participant's ability to comply with study requirements

• Unwilling to discontinue use of conventional multivitamin/mineral or other supplements at least two weeks prior to the study start

• Participating in or planning to begin a weight loss diet during the study period

• Chronic use of over-the-counter medication which would interfere with study endpoints including NSAIDS, laxatives and antacids

• Difficulty in swallowing pills

• Lifestyle or schedule incompatible with the study protocol

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Inflammation

Intervention

Dietary Supplement:
• Placebo
7-pill placebo dietary packed visually identical to active dietary supplement
• Antioxidant, anti-inflammatory dietary supplement
A combination of dietary supplements including: ß-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

Locations

Country	Name	City	State
n/a

Sponsors (2)

Lead Sponsor	Collaborator
Utah State University	USANA Health Sciences, Inc

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Forced vital lung capacity (FVC)		Six times over 3 months to coincide with high and low PM2.5 exposure	No
Secondary	Forced expiratory volume in first second (FEV1)		Six times over 3 months to coincide with high and low PM2.5 exposure	No
Secondary	Fractional exhaled nitric oxide (FeNO)		Six times over 3 months to coincide with high and low PM2.5 exposure	No
Secondary	C-reactive protein		Six times over 3 months to coincide with high and low PM2.5 exposure	No