Alzheimer's Disease: Slower Progression with Omega-3 Fatty Acids

The OmegaAD study reveals that supplementation with omega-3 from fish oil slows down cognitive decline in moderate forms of Alzheimer's disease. Alzheimer's disease is a highly debilitating illness, characterized by the progressive decline of cognitive abilities, learning, and memory. Medications treat the symptoms but have no effect on the causes of the disease or its progression.

Epidemiological studies suggest that a fish-rich diet may protect against the onset of Alzheimer's disease, and researchers decided to investigate the role of the omega-3 fatty acids EPA and DHA. The Swedish study OmegaAD, conducted by scientists from the "Karolinska Institutet," is the first clinical study to use fish oil in the treatment of Alzheimer's disease. The results obtained indicate that supplementation with omega-3 fatty acids from fish oil can slow cognitive decline in some patients with a very moderate form of Alzheimer's disease, although this does not seem to be the case in patients suffering from a more advanced form of the disease.

Omega-3s Slow Down Cognitive Decline Associated with Alzheimer's

The study involved 204 patients with mild to moderate Alzheimer's disease, in stable conditions of the disease. These patients were randomly assigned to take omega-3 fatty acids (1.7g of DHA and 0.6g of EPA) or placebo, for 6 months. After 6 months, all subjects received omega-3 fatty acid supplementation for another 6 months. At the end of the first 6 months, a significant reduction in cognitive decline was observed in a subgroup of patients (n=32) with very mild cognitive dysfunction, among those treated with omega-3 fatty acids compared to patients who took the placebo. Similarly, a slowing of cognitive decline was observed between the 6th and 12th month in the subgroup that took the placebo when supplementation with omega-3 EPA and DHA started.

Not Effective for More Advanced Alzheimer's Disease

In contrast, no difference in the progression of cognitive decline was observed in patients with a more advanced form of the disease. The researchers argue that the mechanisms through which omega-3 fatty acids work are not entirely clear, but that their potent anti-inflammatory capabilities may play a fundamental role in preventing the onset of Alzheimer's disease. It appears that in the two years prior to the onset of the disease, there is a strong inflammatory state that is potentially treatable. It is essentially possible that the clinical stage at which Alzheimer's disease becomes clinically evident is characterized by neural impairment such that even a potent anti-inflammatory treatment like omega-3 fatty acids would be ineffective.

Source

Omega-3 fatty acid treatment of 174 patients with mild to moderate Alzheimer's disease (OmegAD): a randomized double-blind trial, Freund Levi et al., Archives of Neurology, 2006; 63:1402-1408.