This week, I’m following up on Sonia Lupien, the Montreal researcher chronicled by Christa in her 9/8/08 post. Christa sent me a fascinating study published in Psychoneuroendocrinology (2005: 30; 225-242).
Using cortisol levels as a biomarker for stress, Dr. Lupien found that some adults run chronically higher levels of cortisol than others. Over several years, this group had more memory loss and 14% shrinkage of the hippocampus, (a major brain memory center), compared with those with low or moderate levels.
This appears to support Christa’s theory that stressful environments (read “institutional care”) may actually accelerate memory loss over time.
But there’s an even bigger story…
Dr. Lupien looked at children and adolescents and found different cortisol patterns in those with a lower socioeconomic status (SES). Children with low SES and higher cortisol levels also appeared to process thoughts more negatively, which could also lead to more depression. Stressful living environments clearly seem to influence how children view the world.
But what about their cognition? It is well recognized that people with fewer years of education have a higher incidence of Alzheimer’s disease. Decreased “brain reserve” is theorized, but I never quite accepted this, because many people with high IQs do not pursue advanced degrees.
However, most people of low SES have fewer options for advanced education. Maybe the real cause of increased dementia in the less-educated group is poverty, and the day-to-day stress this group encounters. With a widening gulf between haves and have-nots in the world, what will happen as this population ages down the road?
Two weeks ago, I gave the U.S. low marks in the fundamentals of health, education and welfare. I thought I was digressing into politics, but maybe I was talking about dementia all along!