Dietary Intervention Increasing Omega-3 Intake

The goal of this pilot intervention is to evaluate the feasibility of a food voucher program and dietary counseling to increase dietary intake of omega-3 fatty acid in individuals with COPD.

This hypothesis is based on a number of recent observations. Studies have investigated the impact of omega-3 fatty acids, especially Eicosapentaenoic acid (EPA), Docosahexaenoic acid (DHA), alfa-linolenic acid (ALA) intake in chronic diseases and show a link with decreased systemic inflammation measured by cytokines including interleukin 1 (IL-1B), interleukin 6 (IL-6), interleukin 10 (IL-10), tumoral necrosis factor alfa (TNF-α) and eicosanoids; and improved outcomes. In a large cross-sectional study of individuals with COPD, a diet rich in the omega-3 ALA was associated with lower serum TNF-α levels while a diet rich in the omega-6's LA and arachidonic acid (AA) had higher systemic inflammatory markers IL-6 and c-reactive protein (CRP). Other recent nutritional epidemiological study showed the association of greater intakes of omega-3 fatty acids with better lung function profile, but also a slower forced expiratory volume at the 1 second (FEV1) decline in the same smoker cohort.

Preliminary cross-sectional data (n=59), from the CLEAN Air study, reported that at baseline, a higher omega 3 dietary intake was linked with reduced systemic inflammation (IL-1B) and improved respiratory outcomes (a 28% decrease in the odds of COPD symptoms in moderate-severe COPD and conversely, higher omega-6 levels associated with worse outcomes, including increased dyspnea and lower lung function. These findings support the importance of implementing an intervention program to confirm there is a beneficial association between fatty acid dietary intake and reduced COPD symptoms.

To this end, the investigators propose a pilot intervention study in 20 subjects to see if the investigators can increase omega-3 dietary intake over a 4 week period. The investigators will measure self-report dietary intake of omega 3 and 6 fatty acids, as well as measure, fasting plasma fatty acid levels, before and after the intervention.

Inclusion criteria

• Age ≥ 40 years,
• Physician diagnosis of COPD, Global Initiative for Obstructive Lung Disease (GOLD) Stage II-IV disease with Forced -Expiratory Volume (FEV1)/ Forced Vital Capacity (FVC) <70% and FEV1 (% predicted) <80%,
• Tobacco exposure ≥ 10 pack-years
• Former smoker with an exhaled Carbon Monoxide (eCO)<=6 ppm to confirm smoking status
• No home smoking ban.
• Subjects with low omega-3 intake (EPA+DHA levels <500mg) based on data extracted from a food frequency questionnaire (FFQ) completed before the randomization.

Exclusion criteria

• Chronic systemic corticosteroids,
• Other chronic lung disease including asthma,
• Living in location other than home (e.g., long term care facility)
• Homeowner or occupant planning to move or change residence within study period.