Research News: HDL Cholesterol Genotype Is Associated With Longevity and Preservation of Cognitive Function.

Persons with genotype linked to increased levels of HDL cholesterol are more likely to retain good cognitive function later in life than those without this genotype, according to data presented on 19th  Annual Meeting of the American Neuropsychiatric Asociation. This gene protects against vascular disease.

Homozygosity for the 1405V functional variant of the cholesteryl ester transfer protein (CETP) gene was strongly associated with exceptional longevity. In the present study the same variant was associated with preservation of cognitive function.

The genotypic association parallels the phenotypic association. Both lipoprotein particle size and HDL cholesterol level, which is associated with the CETP genotype, have been independently associated with protection against Alzheimer’s disease and other forms of dementia. This association does not confirms causation, said Nir Barzilia,MD Director of the Institute for Aging Research at Albert Einstein College of Medicine in New York City.  Activation of CETP gene will increase HDL cholesterol which prevent dementia.

Dr. Brazilia’s study in 2003 demonstrated that CETP1405V gene was almost three times greater in a population with an average age of nearly 100 than it was in comparison with of individuals with a median age about 70. Subsequent Italian study had similar results.

An obvious hypothesis was that an extended survival is a product of a low risk of a vascular disease, which is the most common cause of death in industrialized countries.

Dementia, on the other hand is associated  with lipid metabolism.

Among those with a GOOD cognitive function the  proportion with the high HDL, Larger average size of HDL, higher apolipoprotein A-1 levels, and CETP1495V genotype was twice as great as it was in those with poorer cognitive function.

It is reasonable to speculate that that elevated HDL protects the vascular integrity of the aging brain, but there is the potential for another independent factor as a protection, like antioxidative effects of HDL in CNS.  
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Neuroleptics produce no cognitive or neuropsychiatric benefits compared with placebo in patients with Alzheimer’s disease, according to a study published in April issue of PLoS medicine. Patients with thiridazine, chlorpromazine, haloperidol trifluoperazine, or resiridone for behavior or psychiatric disturbances in dementia for at least three months were bluntly randomized.

Depression may increase the risk for Alzheimer’s disease.
Reverse causality hypothesis – patients with Alzheimer had a history of depression. In this case if depression predicts the loss of cognitive function, depression should increase before symptoms of dementia, but it is not a case, said Dr Robert S. Wilson, PhD senior neuropsychologist from the Rush Alzheimer’s Disease Center in Chicago study 917 nuns, priests, and monks from the Religious Order study for 13 years. Some people thought that it is true for women, but this also was not confirmed. May be it is the other way around – people with dementia developed depressive symptoms as a reaction to their disease.

Chronic Insomnia Affects Functioning of Adolescents.
In March issue of Journal of Adolescent Health a research team from University of Texas uder leaderships of Robert E. Roberts, PhD reports that chronic insomnia produced burdens similar to other neuropsychiatric diseases on adolescents life.

The assessed 4,175 youths ages 11 to 17. Nearly 27% reported at least one symptoms of insomnia, and about 5% met criteria for insomnia. At one year follow up about 46% still had symptoms of insomnia, and 33.5% reported excessive daytime sleepiness and fatigue. Full set of DSM-IY for insomnia met 24% on follow up. Insomnia predicts neuropsychiatric problems and in reverse, neuropsychiatric problems produce insomnia.

About 50% of adolescence had one or two medical contacts, and received more mental health care contacts. – Depression, ADHD, substance abuse

One or more sleep disorders increases likelihood of negative behavioral outcomes.
Jedish Owens, MD in April Archives of Pediatric and Adolescent Medicine.
In a retrospective study of 235 children ages 3-18 were underwent a polysomnography. $40.9% had a breathing disordered problems with RDI -1-4.99.

49% of children had another sleep disorder. Those children more likely had behavioral, emotional and learning problems. Another factors were duration of sleep and weight. More than 56% children  were overweight, and about 36$ were too short sleepers.  The majority of children in this group were classified as having ADHD.

Sleep duration was moderately negatively correlated with aggressive behavior, social problems, delinquent behavior, anxiety.

Ref: Owen JA, Mehlenbeck R, Lee J, King MM. Effect of weight, sleep duration, and comorbid sleep disorders on behavioral outcomes in children with sleep disordered breathin. Arch. Pediatr. Adolesc. Med. 2008, 162 (4); 313-321.

Problem solving skills may alleviate depression among  caregivers of stroke survivors.
Problems skills refers refer to cognitive and behavioral strategies persons  use to better understand and systematically manage their problems.

Switching to a Non- SSRI Decreases Risk of Depression.
If patients who are SSRI resistant are switched to non-SSRI antidepressants they experienced remission better than if switched to a second SSRI. According to a metw analysis published in the April Issue Biological Psychiatry, 2008.
The results were based on 1.496 patients with SSRI resistant depression.
There were no explanation of this phenomenon, but nevertheless it is clinically relevant.
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Neuroimaging Reveals Insight Into the Teenage Brain.
Teens brain is different from brain of children or adults, according to data from the Longitudinal Brain Imaging Project  of the NIMH Child Psychiatry Branch.

Adolescence is a time of substantial neurobiologic and behavioral change, but the teen brain is not broken or defective adult brain” – said Jay N. Giedd, MD Chief of the Brain Imaging Unit of the Child Psychiatry Branch at the Bethesda, Maryland.

This project began in 1989 and as of September 2007 , includes 5.000 scans from 2000 participants who are seen at two years intervals for brain imaging, neuropsychologic and behavior assessment, and collection of DNA. Data from 387 subjects ages 3 to 27 free from psychopathology were studied for brain development.

According Dr. Giedd, there were three themes as an outcome of this study.

The first is that  there are  functional and structural increases in connectivity and integrative processing as distributed brain modules become more integrating with aging.  “If we consider a literary/linguistic metaphor, maturation would not be an addition of  new letters but combining  earlier former letters into words, and then sentences, and then sentences into paragraphs”, Dr. Giedd elucidated.

The second theme is that there is a general pattern of childhood peaks followed by adolescent declines for gray matter volumes, number of synapses, glucose use, EEG power, and neurotransmitter receptor densities. The powerful process of overproduction followed by selective / competitive elimination that shapes the developing nervous system in utero seems to continue to refine the brain throughout adolescent development.

The third theme is that a changing balance between limbic / subcortical function and frontal lobe function extends well past adolescence and into young adulthood. This is characterized by  increased executive functioning, including attention, response inhibition, regulation of emotions, organization, and long-range planning. Both structural MRI and fMRI show that activity in frontal lobe (vs striatal or limbic activity) increases from childhood to adulthood for various cognitive tasks.

“Adolescents self-esteem, family and school connections, and belief system have been identified as protective factors for positive adolescent emotional health.

If one conceptualizes these elements of societal guidance as the “brake” for reckless adolescent behavior before the inhibitory prefrontal cortex is fully developed, then one can understand that our forefathers were correct in providing structure and guidance for developing adolescents through close family, school, and community relationships”.

These words about the medical basis of strict discipline for adolescents came out not from the old time conservative politician but from a very contemporary and very gentle women, Dr. Elizabeth R. McAnarney, MD of the Department of Pediatrics at the Rochester Medical Center in New York.

Ref: Janis Kelly.  NeuroPsychiatry Reviews, 2008, May: 20
Giedd JN. The Teen Brain: insights from neuroimaging.
.J. Adolesc Health, 2008;42 (4):335-343.
McAnarney ER. Adolescent Brain development: forging New links?
J. Adolesc Health; 2008; 42 (4): 321 – 323