25/05/2011
- Publicado en PUFA Newsletter
imprimir 
Altas ingestas de DHA se asocian con un menor riesgo de padecer demencia
Fecha: 01/04/2011
Autor: PUFA Newsletter
Fuente: “High dietary and plasma levels of the omega-3 fatty acid docosahexaenoic acid are associated with decreased dementia risk: the Rancho Bernardo study”. J Nutr Health Aging 2011. Autores: Lopez LB, Kritz-Silverstein D, Barrett Connor E.
Sinopsis:
Un estudio realizado sobre 266 ancianos describe las asociaciones entre los niveles de DHA y el riesgo de padecer demencia o Alzheimer.
ARTÍCULO:
Higher DHA Intakes Associated with Substantially Lower Chance of Dementia
There is a strong rationale for seeking possible connections between the consumption of long-chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFAs) and a lower chance of developing Alzheimer’s disease (AD). This progressive neurodegenerative condition is the most common form of dementia in older adults, which has no cure or prevention. Because docosahexaenoic acid (DHA) is the most abundant PUFA in the brain and is depleted in the brains of individuals with Alzheimer’s disease considerable research has focused on this n-3 LC-PUFA. DHA has been shown to reduce AD amyloid-βpathology, and dendritic damage, as well as decrease inflammation. Plasma phospholipids of individuals with AD have significantly lower concentrations of DHA compared with non-demented individuals. Moreover, some studies have reported a lower risk of AD among people who consume fish frequently compared with those who rarely eat fish. As often happens with epidemiological studies, findings are inconsistent.
A new report from a case-control study on heart disease in California describes the associations between DHA in the diet or plasma and the risk of all-cause dementia or AD in 266 elderly individuals living in the Rancho Bernardo community. From 1988 to 1991, participants provided dietary information and underwent 5 neuropsychological tests to assess their cognitive function. Individuals who were 65 years of age or older were considered at increased risk for dementia if they failed 3 or more tests. These individuals underwent extensive neuropsychological testing from 1991 to 1993, plus computerized tomography of the brain. Based on their test results and clinical assessments, participants were classified as having possible or probable AD. Those considered to have all-cause dementia included AD cases as well as vascular, mixed and multi-infarct dementia. Age- and sex-matched individuals with good performance on all tests were invited to serve as controls. Individuals with dementia and control participants averaged 81 and 75 years of age, respectively.
Overall, there were 266 participants of whom 42 had possible or probable all-cause dementia. AD was considered possible or probable in 30 of the 42 cases. Nearly 60% of all participants never ate fish. About 15% of participants ate fish once a week or more. Those in the demented category had significantly lower fish and DHA intakes than controls.
Participants in the highest tertile of plasma DHA were 65% less likely to have all-cause dementia and 60% less likely to have AD (Table). Similarly, those in the highest tertile of dietary DHA consumption were 73% and 72% less likely to have all-cause dementia or AD, respectively. All analyses were adjusted for age, sex, education, ApoE, and history of stroke. Further adjustment for systolic blood pressure, smoking, alcohol intake, exercise, diabetes and body mass index did not affect these associations. Individuals in the lowest tertile had a 2.4- and 2.3-fold greater chance of all-cause dementia and AD, respectively, compared with those in the highest two tertiles of plasma DHA.
Likewise, those with the lowest dietary DHA consumption had a 4.3- and 3.4-fold greater risk of all-cause dementia and AD, respectively, compared with those in the highest two tertiles.
One of the strengths of this study is its rigorous screening of participants for dementia. Using a battery of tests plus clinical evaluation would likely reduce the number of misclassified participants. This interpretation is buttressed by the differences in ages between the controls and cases, which were an average of 6.7 years older. Another strength is the use of plasma as a biomarker for DHA exposure. The investigators noted that all DHA variables were highly correlated as one might expect to find.
Even though only a small proportion of participants ate fish more than weekly, those who did clearly benefitted from greater consumption of DHA and a significantly lower risk of dementia. Although these findings show an inverse association between DHA and the risk of dementia, they do not demonstrate a cause and effect relationship.
Fecha: 01/04/2011
Autor: PUFA Newsletter
Fuente: “High dietary and plasma levels of the omega-3 fatty acid docosahexaenoic acid are associated with decreased dementia risk: the Rancho Bernardo study”. J Nutr Health Aging 2011. Autores: Lopez LB, Kritz-Silverstein D, Barrett Connor E.
Sinopsis:
Un estudio realizado sobre 266 ancianos describe las asociaciones entre los niveles de DHA y el riesgo de padecer demencia o Alzheimer.
ARTÍCULO:
Higher DHA Intakes Associated with Substantially Lower Chance of Dementia
There is a strong rationale for seeking possible connections between the consumption of long-chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFAs) and a lower chance of developing Alzheimer’s disease (AD). This progressive neurodegenerative condition is the most common form of dementia in older adults, which has no cure or prevention. Because docosahexaenoic acid (DHA) is the most abundant PUFA in the brain and is depleted in the brains of individuals with Alzheimer’s disease considerable research has focused on this n-3 LC-PUFA. DHA has been shown to reduce AD amyloid-βpathology, and dendritic damage, as well as decrease inflammation. Plasma phospholipids of individuals with AD have significantly lower concentrations of DHA compared with non-demented individuals. Moreover, some studies have reported a lower risk of AD among people who consume fish frequently compared with those who rarely eat fish. As often happens with epidemiological studies, findings are inconsistent.
A new report from a case-control study on heart disease in California describes the associations between DHA in the diet or plasma and the risk of all-cause dementia or AD in 266 elderly individuals living in the Rancho Bernardo community. From 1988 to 1991, participants provided dietary information and underwent 5 neuropsychological tests to assess their cognitive function. Individuals who were 65 years of age or older were considered at increased risk for dementia if they failed 3 or more tests. These individuals underwent extensive neuropsychological testing from 1991 to 1993, plus computerized tomography of the brain. Based on their test results and clinical assessments, participants were classified as having possible or probable AD. Those considered to have all-cause dementia included AD cases as well as vascular, mixed and multi-infarct dementia. Age- and sex-matched individuals with good performance on all tests were invited to serve as controls. Individuals with dementia and control participants averaged 81 and 75 years of age, respectively.
Overall, there were 266 participants of whom 42 had possible or probable all-cause dementia. AD was considered possible or probable in 30 of the 42 cases. Nearly 60% of all participants never ate fish. About 15% of participants ate fish once a week or more. Those in the demented category had significantly lower fish and DHA intakes than controls.
Participants in the highest tertile of plasma DHA were 65% less likely to have all-cause dementia and 60% less likely to have AD (Table). Similarly, those in the highest tertile of dietary DHA consumption were 73% and 72% less likely to have all-cause dementia or AD, respectively. All analyses were adjusted for age, sex, education, ApoE, and history of stroke. Further adjustment for systolic blood pressure, smoking, alcohol intake, exercise, diabetes and body mass index did not affect these associations. Individuals in the lowest tertile had a 2.4- and 2.3-fold greater chance of all-cause dementia and AD, respectively, compared with those in the highest two tertiles of plasma DHA.
Likewise, those with the lowest dietary DHA consumption had a 4.3- and 3.4-fold greater risk of all-cause dementia and AD, respectively, compared with those in the highest two tertiles.
One of the strengths of this study is its rigorous screening of participants for dementia. Using a battery of tests plus clinical evaluation would likely reduce the number of misclassified participants. This interpretation is buttressed by the differences in ages between the controls and cases, which were an average of 6.7 years older. Another strength is the use of plasma as a biomarker for DHA exposure. The investigators noted that all DHA variables were highly correlated as one might expect to find.
Even though only a small proportion of participants ate fish more than weekly, those who did clearly benefitted from greater consumption of DHA and a significantly lower risk of dementia. Although these findings show an inverse association between DHA and the risk of dementia, they do not demonstrate a cause and effect relationship.
- © 2010 ExpertOmega3 |
- Aviso Legal |
- Política de privacidad |
- Contacto |
- PRENSA
- Entidades colaboradoras:
