Positive Health Online

Abstract

WANG and COLLEAGUES,  Department of Medicine, Oregon Health and Science University, Portland, OR 97239, USA. wangwe@ohsu.edu studied association between carotenoids, which may protect n-3 fatty acids, and severity of dementia in patients with Alzheimer's Disease.

Background

Carotenoids are fat-soluble antioxidants that may protect polyunsaturated fatty acids, such as n-3 fatty acids from oxidation, and are potentially important for Alzheimer's disease (AD) prevention and treatment.

Methodology

Fasting plasma carotenoids were measured in 36 AD subjects and 10 control subjects by HPLC. Correlations between plasma carotenoid levels, red blood cell (RBC) n-3 fatty acids, and dementia severity were examined in AD patients.

Results

Moderately severe AD patients (MMSE=16-19) had much lower plasma levels of two major carotenoids: lutein and beta-carotene, compared to mild AD patients (MMSE=24-27) or controls. Among AD patients, variables (lutein, beta-carotene, RBC docosahexaenoic acid (DHA) and LDL-cholesterol) were significantly correlated with MMSE. A lower MMSE score was associated with lower lutein, beta-carotene and RBC DHA levels, and a higher LDL-cholesterol level. These variables explained the majority of variation in dementia severity (55% of variance in MMSE). Lutein, beta-carotene and beta-cryptoxanthin were positively correlated with RBC DHA in AD patients. The association between higher carotenoids levels and DHA and higher MMSE scores, supports a protective role of both types of nutrients in AD.

Conclusion

These findings suggest targeting multiple specific nutrients, lutein, beta-carotene, and DHA in strategies to slow the rate of cognitive decline.

References

Wang W, Shinto L, Connor WE and Quinn JF. Nutritional biomarkers in Alzheimer's disease: the association between carotenoids, n-3 fatty acids, and dementia severity. Journal of Alzheimer's Disease. 13 (1): 31-8. Feb 2008.