In the news round-up this week, there have been some large genome wide association studies in people with schizophrenia with significant findings on chromosome 6 while another study provided further support for an association between schizoaffective disorder and the GABA receptor gene. There was another study which showed an intriguing association between hypertension and response to stress as well as a meta-analysis looking at how people respond to information which contradicts their beliefs.
Research in Dementia
In a study of relevance to old age liaison services, the authors of a longitudinal study looking at older adults admitted as emergencies to hospital characterised the prevalence of dementia according to age stratifications. The authors found an as expected increase in prevalence with age rising to 75% over the age of 90 in women and 48.8% in men over the age of 90. 41.3% of admissions resulted from urinary tract infections or pneumonia(Sampson et al, 2009)(STT3).
Research in Mood Disorders
A randomised control trial looked at computerised CBT (cCBT) delivery in a primary healthcare setting. The 303 participants with depression were allocated to treatment as usual, cCBT (using the Colour Your Life program and without support) or cCBT plus treatment as usual. In the first two groups there was a relatively poor adherence to treatment but in the analysis there was found to be no significant difference between the groups on the primary outcome measure – BDI-II scores. The authors conclude that supported cCBT might fare better. It would be interesting to see if the program could be modified to increase adherence rates (de Graaf et al, 2009). In a study of 1147 parents (>60 years old) whose children migrated out of the district of the parent there was found to be a decreased prevalence of depression in the parents (article freely available here)(Abas et al, 2009)(STT3).
Research in Psychosis
The authors of a paper propose that Toxoplasma Gondii may produce psychosis in hosts as a mechanism to enhance fitness of the pathogen and advocate further research to test their hypothesis (da Silva and Langoni, 2009)(STT6). The authors of a genome wide analysis (analysing the data from a previously published study) found significant evidence of an association between the research diagnostic criteria Schizoaffective Disorder Bipolar type and variations in the GABA receptor particularly GABRB1 which they argue is further evidence in support of the diagnosis of Schizoaffective Disorder and it will be interesting to see further studies examining this potential relationship more closely (article freely available here)(Hamshere et al, 2009)(STT5).
News In Brief
A widely reported case-control study in Nature (also here, here, here and here although some of the reported sample sizes differ) looked at copy number variants in people with (n=3332) and without (n=3587) schizophrenia. The researchers found that there was a large number of variants that were associated with schizophrenia and were also found in people with bipolar disorder. Furthermore these variants were estimated to contribute to a third of the risk for schizophrenia. Two further studies were conducted by different groups and the results from all three were pooled. Significant associations were found with the Major Histocompatability Complex on Chromosome 6 as well as the myosin gene. The authors of a longitudinal Finnish study involving 2000 middle-aged subjects who were followed up over 20 years later provided further evidence that the APOE 4 variant was associated with a higher prevalence of Alzheimer’s Disease. A similar increase was also found in association with being separated from a partner before age fifty. A study has provided indirect evidence that Granulocyte Colony Stimulating Factor (GCSF) might prevent the build up of Beta-Amyloid plaques in the brain which would be relevant in Alzheimer’s Disease. It will be interesting to follow further studies in this area.
The authors of a meta-analysis looking at data involving over 8000 subjects concluded that people are more likely to discount information that contradicts the beliefs they already hold and that this tendency is influenced by a number of factors including personality type as well as the context of these beliefs. The authors of a paper looking at studies reported as randomised controlled trials in China identified 2235 studies and contacted the authors/coauthors. They report that less than 7% of the studies referred to as randomised controlled trials involved true randomisation. However this will not be limited to China and is relevant to the wider issue of research methodology.
An intriguing study with many ramifications involved looking at the effects of anger on measures of carotid artery flow in 3 groups of subjects of increasing age. The researchers found that anger was associated with vasodilation of the carotid arteries and that this effect did not occur in those with hypertension suggesting a possible mechanism for stress associated myocardial infarct. The authors of a recent survey of people who remained at home in New Orleans during Hurricane Katrina suggest on the basis of the results their decisions may be related to valuing a sense of community and that they did not view themselves as ‘powerless’. Repeating positive self-statements was associated with a decrease in self-esteem in those with already low self-esteem compared to those with high self-esteem in one study.
The authors of a genetic study conducted in samples from a number of different ethnic groups have reported an association between perfect pitch and chromosome 8. A small fMRI study provided evidence of increased activity in the inferior frontal sulcus during language tasks involving identification of different pronunciations. The authors suggest that this region is involved in categorisation for both language and non-language activities.
Abas MA, Punpuing S, Jirapramukpitak T, Guest P, Tangchonlatip K, Leese M, Prince M.Br J Psychiatry. 2009 Jul;195(1):54-60. Rural-urban migration and depression in ageing family members left behind.
Hamshere ML, Green EK, Jones IR, Jones L, Moskvina V, Kirov G, Grozeva D, Nikolov I, Vukcevic D, Caesar S, Gordon-Smith K, Fraser C, Russell E, Breen G, St Clair D, Collier DA, Young AH, Ferrier IN, Farmer A, McGuffin P; Wellcome Trust Case Control Consortium, Holmans PA, Owen MJ, O’Donovan MC, Craddock N. Br J Psychiatry. 2009 Jul;195(1):23-9. Genetic utility of broadly defined bipolar schizoaffective disorder as a diagnostic concept.
de Graaf LE, Gerhards SA, Arntz A, Riper H, Metsemakers JF, Evers SM, SeverensJL, Widdershoven G, Huibers MJ.Clinical effectiveness of online computerised cognitive-behavioural therapywithout support for depression in primary care: randomised trial. Br J Psychiatry. 2009 Jul;195(1):73-80.
da Silva RC, Langoni H. Toxoplasma gondii: host-parasite interaction and behavior manipulation. Parasitol Res. 2009 Jun 23. [Epub ahead of print].
Sampson EL, Blanchard MR, Jones L, Tookman A, King M. Br J Psychiatry. 2009 Jul;195(1):61-6. Dementia in the acute hospital: prospective cohort study of prevalence and mortality.
Steps To Treatment (STT)
STT = Steps To Treatment. An estimate of the number of steps between the results and translation into treatment. This is an opinion.
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