At the Alzheimer’s Research Forum there is an interesting write-up of research currently underway in Colombia which involves families with early-onset Alzheimer’s Disease. The write-up emphasises some of the profound ways in which early-onset Alzheimer’s Disease affects families. In one study, the researchers looked at the sensitivity of the ADAS-cog instrument in people with Alzheimer’s Disease. They found that at different stages of the illness, different components of the ADAS cog were effective in detecting treatment effects. A Polish group have reported on differences between people with Alzheimer’s Disease and healthy controls in performance on the pocket smell test providing further evidence of the potential importance of odour discrimination dysfunction as a correlate of pathology. In a small study (n=76), researchers used new research diagnostic criteria to establish diagnosis and then assessed a number of biomarkers. In keeping with biomarker findings in Alzheimer’s Disease, medial temporal lobe grey matter atrophy (using MRI) was characteristic of the prodromal Alzheimer’s Disease group but the researchers did not find any significant differences in regional grey matter volume between the prodromal Alzheimer’s Disease group and participants with Alzheimer’s Disease. In a small study (n=20), cerebral acetylcholinesterase (AChE) levels were assessed using the tracer (11)C-MP4A (using PET imaging) in people with Multiple Sclerosis (MS) with secondary progressive cognitive impairment and also in healthy controls. The researchers found that there was no difference in AChE levels between the two groups but within the MS group there was an inverse correlation between AChE levels and cognitive performance including MMSE scores and it will be interesting to see the results of larger replication studies.
One of the emerging findings in Alzheimer’s Disease research is a protective role for the Mediterranean Diet. There have been various suggestions for this relationship including a reduction in Cerebrovascular Disease. In one study researchers investigated the relationship between mediterranean diet and cerebrovascular events (n=707). Participants were stratified into low, moderate and high adherence to the Mediterranean diet. The most interesting finding was that there was a significant reduction in prevalence of infarcts in the highest adherence group. The odds ratio for this group (compared to the low adherence group) was 0.64, significant at the 5% level and with the 95% confidence interval between 0.42 and 0.97.
In a paper published in the Proceedings of the National Academy of Sciences (freely available here) one group of researchers have used a large dataset to analyse genetic variation in human populations in Africa. Previously it has been thought that global human populations originated in East Africa. The researchers in this study confirmed previous findings about genetic diversity in specific ethnic groups in Africa including the Khomeni bushmen of Southern Africa and concluded that human populations originated in Southern Africa. However there is an interesting commentary from Professor Chris Stringer in this article that places these findings in context.
In terms of human evolution a very important part of understanding relates to the behaviour of archaic hominid ancestors. In a recent study, one group has dated a Homo Erectus stone tool factor to between 600,000 and 620,000 years ago. They found a large number of stone tools there which is suggests amongst other possibilities a complex social organisation. In another long term study, one group has identified several Neanderthal sites at high altitude (they were previously thought to be found only in low altitude habitats) in the Greek Mountains. What is particularly interesting about these findings is that these sites were revisited over long periods of time possibly up to thousands of years.
Index: An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail firstname.lastname@example.org. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.