Is Cancer the Cure for Alzheimer’s disease?

 In 2014 Ferrán Catalá-López and his colleagues from the University of Valencia in Spain reviewed the inverse association between cancer and neurological diseases including dementia. What they reported is that numerous studies have been showing that if you had one of these two diseases you are less likely to get the other. The first anecdotal evidence came more than fifty years ago when patients with Parkinson’s disease were reported to have a lower rate of cancers. More recently, this inverse relationship has also been documented for Alzheimer’s disease. In fact, this inverse relationships is most pronounced with Alzheimer’s disease and Huntington’s disease. While for cancer it is more pronounced for colorectal cancer and lung cancer.

If you have had cancer you are 50% less likely to get Alzheimer’s disease. While, if you have Alzheimer’s disease you are 60-70% less likely to get cancer. The same results do not exist for vascular dementia or Lou Gehrig's disease (ALS) and for some cancers such a melanoma, non-melanoma skin cancer and breast cancer.

There could be a number of reasons for this, and all could be working at the same time. It could be that once you are diagnosed with cancer or Alzheimer’s disease the focus of clinical care is on treatment and there might be less active interest in searching for additional diseases. However, this does not explain why it does not work with other diseases. It could be that the therapy for both diseases protects you from getting the other disease. Although plausible, it is unlikely. It could also be that the two diseases are separated by vulnerability in age and therefore if cancer kills you first you will not have the opportunity to get dementia. While being spared cancer you are then more likely get dementia. Although there are studies that dispel these arguments—some more conclusively than others—there is however a more subtle and persuasive argument.

There is a growing understanding of the chemical balance that is played in the body especially the process of generating energy for cells. The imbalance in this process—known as Glycolysis—of how the body converts sugar into fuel (pyruvate) for cells could be the balance that determines which of these two diseases you are likely to get. Too little fuel for cells—since neurons have such energy demands—and you get Alzheimer’s disease. Too much fuel, which feeds the erratic cells, and you get cancer.

Although this is an interesting avenue for biological and chemical research, there is an additional offshoot of this way of thinking…and that is the rejuvenation of the concept of homeostasis. That along a continuum of cancer or Alzheimer’s disease there is a balance. First described by Claude Bernard in 1865 and later coined by Walter Bradford Cannon in 1926, homeostasis requires three basis mechanisms. A sensor to detect changes, a mechanism that can modify that change, and a feedback connection between the sensor and a mechanism. The concept that homeostasis can determine Alzheimer’s disease has radical repercussions for psychologists because both the sensor and the mechanism can have psychological components. As an example, for the sensor being happy and content, tells the body that the system is in homeostasis, in balance while being stressed tells a different story. For the mechanism, being active, engaging and having tactile and sensory stimulation moderates and modulates our internal chemistry.

© USA Copyrighted 2014 Mario D. Garrett

Infections/ Antibiotics and older Adults

Despite advances in antibiotic therapy, infectious diseases continue to be a major cause of mortality in older adults. Ritu Banerjee and her colleagues  at the Mayo Clinic have reported that Antibiotic-resistant Escherichia coli (E. coli ST131) continues to proliferate within hospitals and long-term care facilities. In a study published in found that  LTCF residents having 8 times the risk of contracting E.coli ST131 compared with non-LTCF residents. This trend coincides with the increasing prevalence of ST131 among patients 65 years and older. It is likely that extensive antibiotic exposure, close contact with other antibiotic-exposed individuals, age and health-associated alterations in intestinal microbiota all contribute to the high prevalence of ST131 among the elderly population.  ST131 isolates were also more than twice as likely to be healthcare-associated infections as compared to community-associated infections.

The diagnosis of infection in older adults is more challenging, Only 40 percent of older adults with serious infections develop increased white blood count, and since frail older adults tend to have poorer body temperature response, there might not be an perceptible increase in temperature. Body response to infection, among older adults, are subtle, and nonspecific. Such responses might be change in mental alertness and delirium in half of older adults with infections. In addition, anorexia, functional decline, falls, weight loss or a slight increase in respiratory rate may be the only signs indicating infection in older adults.

Is Having Children Detrimental to Longevity?

How can sleep deprivation, economic shocks, diminished disposable income, constant caregiving, incessant worrying, 24/7 responsibility, lack of privacy, and incessant crying be correlated with longer life?   But that is just what a new study from Denmark is reporting. Having children increases your life expectancy.

The study itself is simple.  The Dane Professor Esben Agerbo and his colleagues published a study in 2012 where they looked at 21,276 childless couples who in 1994 went to an in vitro fertilization clinic. All these women had problems conceiving. By 2005 a total of 96 women and 220 men died. Women who did NOT have a child were four times more likely to have died compared to those who did have a child. The inexplicable aspect of this study is that the same disadvantage also transferred to men. Men who remained childless in this study were twice as likely to die early.

How can this be explained? Gerontology theories predict that having children reduces your life expectancy--especially if you stop having sex afterwards--as most couple who have children tend to do. 

The theory of antagonistic pleiotropy argues that some genes have contradictory effects at different age. Genes which might enhance your reproductive success--genes that increase testosterone in men, resulting in more muscle mass and masculine secondary sexual characteristics; or estrogen and bigger breasts in women--may at the same time have detrimental effects on survival later on in life--elevated risk of cancer in men and larger cancer nodes in women. Natural selection tends to favor these kinds of genes because they maximize the ability to transfer your genes—termed as fitness--without due concern for later life mortality.  From this theory it follows that higher rates of reproduction comes at a cost of higher post-reproductive mortality.

As a complementary theory, the Disposable Soma Theory argues that there are metabolic trade-off between reproduction and longevity. Reproduction utilizes biological resources which could otherwise be used for physical maintenance. Having more children to bear and rear uses up limited physical resources that could have promoted better health and a longer life. In this view, higher reproduction is associated with a shorter life span.

These theories are supported by the numerous studies by demographers looking at nuns and monks. Overall, these studies have been showing reduced mortality of 31-11 percent among nuns and monks. An advantage that is generally larger for monks than for nuns. It is more a lifestyle that protects you from dying early (rather than promoting longer life.) In the real world, where people do not live in monasteries/nunneries and where they do not follow a regimented life, it is hard to separate what is causing people to die earlier.

In 2002, using data for a preindustrial Sami population in Finland, Samuli Helle and his colleagues showed that the number of sons--rather than the total number of children--affected women’s longevity. This association was also found in data from a 19th century Flemish village and confirmed the association between number of sons born contributing to their mother’s early age of death. However the effect was only evident among poorer women, and mainly for women whose sons survived to at least to age five. Leading to the conclusion that resource competition--rather than pregnancy--might be the main explanation. Having children is not only a biological event. There is also a financial cost associated between childbearing history and longevity.

Having four or five children shortened women’s life span after 50 by about 3.5 years compared to women with one child or less. However, this effect could only be found among the poorest women. No effect of number of children for more well-to-do women, or for men, could be found.

And the poorer you are the poorer your diet and the harder the competition for resources (both inside the womb and outside.) 

How can this Danish study show such different results? Could we explain the results that having children increased longevity because it is reflecting having less money?

In Denmark, the first three courses of IVF are given free-of-charge. Wealthier couples, who may be able to buy more IVF treatment sessions can increase their chances of pregnancy. So methodologically, there is a higher likelihood that those who conceived were a self selecting richer group making the results already biased. What helped to clarify this point further--that it is socio-economic status which is promoting longer life rather than bearing children--is the finding that researchers found it didn't matter if the women or men who had children had them biologically or through adoption for them to benefit from increased longevity. Being well off  is one of the main criteria for having successful adoption.

The longest person that ever lived, Jeane Lousie Clament had one daughter. But she also did not work, lived a life of leisure, smoked (until she was 117 years) and ate over a kilo of chocolate a week. If children should choose their parents wisely, then similarly parents need to make sure they can afford their children or else pay for it with their life.

© USA Copyrighted 2014 Mario D. Garrett