January 11, 2011
What’s the most effective way to cut your risk of developing Alzheimer’s? A study from France looked at various ways that people might pursue to cut their risk of developing the disease and found that several lifestyle factors may be particularly useful for keeping the mind sharp. Education and learning, eating plenty of fruits and vegetables and avoiding diabetes and depression were found to have the biggest impact on reducing Alzheimer’s risk.
The study looked at 1,433 seniors living in Montpelier, France, whose mean age was 72. All were given memory exams and other tests after two, four and seven years to look for signs of Alzheimer’s, other forms of dementia, or mild cognitive impairment, a form of memory loss that often eventually leads to Alzheimer’s.
Statistical analysis of the patients, reported in the British medical journal, BMJ, identified several factors were particularly important for lowering the risk of Alzheimer’s. Education appeared to have the biggest impact on Alzheimer’s risk, leading to an 18 percent reduction in the incidence of Alzheimer’s or mild cognitive impairment.
The researchers found that scores on a reading test designed to measure lifelong intellectual activity and cultural exposure, or what the researchers call “crystallized intelligence,” were a good indicator of protection against declining memory and other symptoms of Alzheimer’s. Continuing to pursue activities that build vocabulary, increase the depth and breadth of general knowledge, and strengthen the ability to reason using words and numbers, then, ranked high on the list of factors that might prevent memory loss. “The public health message can only be to encourage literacy at all ages, irrespective of innate ability,” the authors write.
Taking steps to prevent and treat depression and diabetes, and eating more fruits and vegetables led to an overall 20 percent reduction in Alzheimer’s incidence. Of these, avoiding depression had the biggest impact; effectively treating depression in elderly patients led to a 10 percent reduction in the number of new cases over the next seven years. The link between depression and Alzheimer’s, though, remains complex. Depression may be an early symptom of Alzheimer’s, occurring years before the onset of the disease. Alternatively, depression may cause brain changes that increase the likelihood of the disease.
Conclusions about other potential modifiable risk factors like high blood pressure, head injuries, or living alone could not be made from this study, in part because of the limited sample size and follow-up period. But earlier studies suggest these and other factors may increase the risk of developing memory problems and Alzheimer’s.
Educational pursuits, avoiding depression and diabetes, and a fruit-and-vegetable-rich diet won’t guarantee that you won’t get Alzheimer’s in old age. Genes like APOE-E4, too, play a role in who gets Alzheimer’s. But some of the factors noted in this study seemed to be more important than the APOE-E4 gene with regard to Alzheimer’s risk.
The authors advise that people take steps to avoid Alzheimer’s in old age. The number of Alzheimer’s cases is expected to mushroom in the coming decades unless new and more effective treatments are found. They note that the number of cases will double in developing countries between 2001 and 2020. They are expected to increase by 300 percent in countries like China, India and south Asian and western Pacific countries. Given the rapidly growing burden of Alzheimer’s, effective strategies to treat and prevent the disease are critical.
Source: K Ritchie, I Carrière, C W Ritchie, C Berr, S Artero, and M-L Ancelin: “Designing prevention programmes to reduce incidence of dementia: prospective cohort study of modifiable risk factors.” BMJ 2010;341:c3885, doi: 10.1136/bmj.c3885 (Published 5 August 2010)