October 28, 2008 (Philadelphia, Pennsylvania) — Omega-3 fatty-acid levels are inversely tied to the apnea–hypopnea index (AHI), researchers told attendees here at CHEST 2008, the American College of Chest Physicians 74th Annual Scientific Assembly.
Obstructive sleep apnea is a risk factor for cardiovascular disease, and previous research has indicated that omega-3 fatty-acid supplementation may be of benefit to patients with cardiovascular disease.
James B. Ladesich, MD, and colleagues from the University of Missouri at Kansas City investigated whether omega-3 fatty-acid levels were related to AHI score in 350 people undergoing sleep studies at their institution. All subjects had AHI scores between 0 and 104.
The researchers used omega-3 levels from red blood cell membranes, which correlate closely with omega-3 tissue levels, to assess the proposed link.
After controlling for a number of factors, including age, sex, body mass index, race, smoking status, fish intake, omega-3 supplementation, flaxseed-oil supplementation, and supplementation of other fatty acids normally present in cell membranes, patients were divided into 3 groups: those with AHI scores between 0 and 14, those with scores between 15 and 34, and those with scores above 35.
Docosahexaenoic acid (DHA) levels were inversely correlated with AHI score, Dr. Ladesich told meeting attendees. As a percentage of total fatty-acid content in red blood cell membranes, DHA levels were:
4.1% (range, 3.4% - 5.3%) for patients with AHI scores between 0 and 14;
4.5% (range, 3.3% - 5.8%) for those with AHI scores between 15 and 34; and
3.6% (range, 2.9% - 4.7%) for those with AHI scores above 35 (P = .03).
"Whether increasingly severe apnea induces systemic changes that lower DHA levels or whether lower DHA levels can lead to worsening apnea is unclear," Dr. Ladesich reported. "Further studies are needed to clarify whether this association is clinically significant."
The investigators stopped short of saying that omega-3 supplementation, such as fish oil or flaxseed oil, might improve AHI scores and decrease the severity of sleep apnea, "but that is the next logical step," said Charles Atwood, MD, Associate Professor of Medicine at the University of Pittsburgh, in Pennsylvania, and Director of Sleep Medicine at the Veterans Affairs Medical Center in Pittsburgh, in an interview with Medscape Pulmonary Medicine during the meeting.
"The findings are interesting but not surprising," Dr. Atwood commented. "They are consistent with other studies that show that sleep apnea causes oxidative stress and puts severe demands on the body. Omega-3 protects against stress, and this kind of long-term stress depletes those levels."
"Studies of vitamins C and E and other antioxidants in patients with sleep apnea haven't yielded much just yet," Dr. Atwood noted, "and there are no clinical treatment indications at this point, but supplementation makes sense in disorders where antioxidants are used up."
Neither Dr. Ladesich nor Dr. Atwood have disclosed any relevant financial relationships.
CHEST 2008: American College of Chest Physicians 74th Annual Scientific Assembly: Poster AP2276. Presented October 28, 2008.
Medscape Medical News © 2008 Medscape
Cite this: Martha Kerr. Omega-3 Fatty Acids Inversely Related to Sleep Apnea Severity - Medscape - Oct 28, 2008.