Enteral omega-3 supplementation not beneficial for acute lung injury patients
MedWire News: Twice-daily supplementation with fatty acids and antioxidants does not improve outcomes in patients with acute lung injury (ALI), show study results.
In fact, the patients who were given supplements had higher mortality and morbidity than the control patients, suggesting that such practice may actually be harmful, say the researchers.
Research suggests that omega-3 fatty acids and antioxidants may help regulate inflammation and improve oxygenation in patients with acute lung injury.
To test this hypothesis, Todd Rice (Vanderbilt Medical Center, Nashville, Tennessee, USA) and colleagues compared the effects of twice-daily enteric supplementation with omega-3 fatty acids, γ-linolenic acid, and antioxidants (n=143) with supplementation with an isocaloric control (n=129) in patients with acute lung injury requiring mechanical ventilation.
The study was stopped early as no clinical benefits were seen in the patients given fatty acids plus antioxidants compared with the controls.
Over 28 days of follow-up, the patients in the fatty acid group had fewer ventilator-free days than those in the control group, at 14.0 versus 17.2.
They also had fewer days off the intensive care unit, at 14.0, compared with 16.7 in the control group and fewer days without nonpulmonary organ failure, at 12.3 versus 15.5 in the control group.
Adjusted 60-day hospital mortality was also significantly higher in the fatty acid group than the control group, at 25.1% versus 17.6%.
The fatty acid supplement also resulted in patients having diarrhea for a significantly greater percentage of ventilated days than those given the control supplement, at 29% and 21%, respectively.
"In contrast to previous studies, in this study enteral supplementation of omega-3 fatty acids, γ-linolenic acid, and antioxidants did not improve lung physiology or clinical outcomes in patients with acute lung injury compared with supplementation of an isocaloric control," write Rice et al in JAMA.
"The reason why twice-daily supplementation failed to alter plasma biological marker levels is unclear. It is possible that more frequent or near-continuous dosing is necessary to see benefits," they say.
"Carbohydrates and protein (as in our control) may result in better clinical outcomes than lipids, and at the same time n [omega]-3 fatty acids may result in better clinical outcomes than n-6 and n-9 fatty acids."
By Helen Albert