Conjugated Linoleic Acid (CLA) as Adjunctive Therapy in Mild Asthmatics: A Pilot Study.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 40
- Locations
- 2
- Primary Endpoint
- PC20 - methacholine sensitivity
Study Overview
Brief Summary
Conjugated linoleic acids (CLA) are naturally occurring free fatty acids derived from the tissues and milk of ruminant animals such as cows. CLA has multiple biological properties including regulation of metabolism and immune processes, including tissue inflammation. Asthma symptoms are caused by irritation and inflammation of the airways. Our hypothesis was that CLA may reduce airway inflammation in asthma and thus reduce asthma symptoms. The aim of this pilot study was to investigate the efficacy and safety of CLA as a dietary supplement in mild asthma. Subjects will be assigned to take CLA dietary supplements or placebo (olive oil) for 12 weeks in addition to their usual asthma treatment. They will be monitored for asthma symptoms, side effects, lung function and blood markers of inflammation.
Detailed Description
Background and Purpose You are being invited to participate in a study of the effects of a natural supplement, conjugated linoleic acid (CLA), on allergy and asthma. Previous studies show that CLA may control the type of inflammation found in allergy and asthma. CLA is found in dairy products, however the amount found varies greatly depending on what the cows have been fed and has reduced dramatically over the last 30 years. The estimated daily intake of CLA is between 15 and 174 mg/day, but an effective dose of CLA is 3000 to 4000 mg/day for a 70 kg adult. Therefore taking CLA supplements may be beneficial. This will be the first formal study to look at whether CLA does benefit people with allergies and asthma.
Study Procedures
If you qualify for the study and agree to participate, you will be randomly assigned (like flipping a coin) into one of two groups. The two groups are:
Conjugated linoleic acid (active substance) twice daily for 3 months Placebo (inactive substance) twice daily for 3 months
Neither you nor the study doctors will know whether you are receiving CLA or placebo. There will be no change in your asthma medications that are prescribed by your regular physician. Your physician will be made aware that you are participating in this study.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Double (Participant, Investigator)
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Mild asthma - FEV1 > 70% predicted Positive methacholine challenge
Exclusion Criteria
- Not provided
Arms & Interventions
2
Olive oil 4.5g/day x 12 weeks.
Intervention: Olive oil (Dietary Supplement)
1
Conjugated Linoleic Acid 4.5g/day in three divided doses p.o. for 12 weeks
Intervention: Conjugated Linoleic Acid (CLA) (Dietary Supplement)
Outcomes
Primary Outcomes
PC20 - methacholine sensitivity
Time Frame: 12 weeks
Secondary Outcomes
- Quality of life (QoL), body mass index (BMI), systemic cytokine levels, and adverse events.(12 weeks)