An earlier blogpost "Premature aging caused by mind wandering?...new research", discussed the research on premature aging and how it could be related to stress. The research @ University of California at San Francisco (UCSF) used "telomere length" (TL) as a indication of stress and biological aging and how "mind wandering" could be an indication of that. (See figure below) Many studies have confirmed this link between telomeres and severe stress. What are telomeres?
Why do we have them?
Telomeres are "caps" over the end of chromosomes to protect them from deterioration or fusion w/neighboring chromosomes. Over time these telomeres break down and get shorter. When they shorten to a critical length, the chromosomes stop functioning or fuse to other chromosomes, and then the residue builds up and leads to illness and aging.
There is a lot of research on stress, aging and telomeres now. Telomeres were found by Lin, et al. in "Telomeres and lifestyle
factors: Roles in cellular aging" in Mutation Research (2011) to
shorten with age and psychological and physiological stress; telomere shortness
predicted early disease and mortality.
Shalev, et al. in "Exposure to violence during childhood is associated with telomere erosion from 5 to 10 years of age: A longitudinal study" in Molecular Psychiatry (2012) showed that telomere shortness is a marker of accelerated aging early in life from exposure to violence.
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| Chromosomes - gray Telomeres - white |
Telomeres are "caps" over the end of chromosomes to protect them from deterioration or fusion w/neighboring chromosomes. Over time these telomeres break down and get shorter. When they shorten to a critical length, the chromosomes stop functioning or fuse to other chromosomes, and then the residue builds up and leads to illness and aging.
This mechanism
apparently evolved to prevent cells from replicating out of control, i.e.
becoming cancerous. Our adaptive
cancer protection, as is typically the case in evolution, is a trade-off, this time between aging and cancer.
There is a lot of research on stress, aging and telomeres now. Telomeres were found by Lin, et al. in "Telomeres and lifestyle
factors: Roles in cellular aging" in Mutation Research (2011) to
shorten with age and psychological and physiological stress; telomere shortness
predicted early disease and mortality. Shalev, et al. in "Exposure to violence during childhood is associated with telomere erosion from 5 to 10 years of age: A longitudinal study" in Molecular Psychiatry (2012) showed that telomere shortness is a marker of accelerated aging early in life from exposure to violence.
So how about cancer? Certainly having serious cancers would be a high stress, high mind-wandering situation. Does telomere length which predicts how we respond to stress with aging, also predict how we handle cancer-induced stress and respond to stress-reducing protocols designed to change our cancer survival rate?
A recent study in Cancer, by Carlson, L. et al. "Mindfulness-based Cancer Recovery and Supportive-Expressive Therapy Maintain Telomere Length Relative to Controls in Distressed Breast Cancer Survivors" looks at how two different stress management techniques and a control approach affected telomere length in stressed breast cancer survivors.
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| Linda Carlson Univ. of Calgary |
The techniques were:
a) "Mindfulness-Based Cancer Recovery" (MBCR) developed by two of the authors, Linda Carlson and Michael Speca of the Oncology Department @ the University of Calgary
b) supportive-expressive group therapy (SET)
c) a 6-hr stress management seminar for controls
As described in the post above, and in "mindfulness meditation - religious vs secular - does it work? - new research", Jon Kabat Zinn's "Mindfulness-Based Stress Reduction" (MBSR) was the key to unlocking the power of mindfulness meditation by moving to a secular, scientifically-validated approach.
MBCR is based heavily on MBSR but tailored for cancer patients. The book on MBCR is even entitled "Mindfulness-Based Cancer Recovery: A Step-by-Step MBSR Approach to Help You Cope with Treatment and Reclaim Your Life".
The 92 participants in the study met four requirements:
a) Completed all medical treatments three months previously
b) Diagnosed with AJCC stage I to III breast cancer
c) Over 18 years old
d) Scored over 4 on the National Comprehensive Cancer Network Distress Thermometer
The MBCR group attended 8 weekly group sessions of 90 minutes, a six-hour retreat, and got a course booklet and CDs for guided meditation and mindful body movement at home. The SET group met for 90 minutes weekly for 12 weeks. Both MBCR and SET had comparable structure, group size, environment and contact time.
There was little difference between MBCR and SET in the telomere lengths (TL) that resulted from the study, so their results were merged. As shown at left, the orange bars are for the combined MBCR and SET intervention results.
T/S is the ratio between the length w/the telomere to the "single-copy gene length". Both MBCR and SET maintained the T/S ratio over the 3 month intervention period. However, the control population had decreased TLs.
This confirmed the Carlson's group earlier study. As the report states "...this finding adds to the literature supporting the potential for stress-reducing interventions to impact important disease-regulating processes and ultimately disease outcome."
There is only one other control-based study on associations between chronic stress levels, TL and cancer. It was done earlier on cervical cancer by Biegler, et al. in 2012 in Cancer Prevention Research @ UC Irvine.
Cervical cancer survivors, like breast cancer survivors, "often experience profound and protracted disruptions in quality of life (QOL) domains" with "exceptional chronic stress, compromising optimal health".
The Nelson group did several studies with cervical cancer survivors using a "culturally-sensitive psychosocial telephone counseling intervention" (PTC) which produced "significantly improved QOL as well as modulation of stress-associated biomarkers".
This study had only 22 participants; 10 received PTC, the rest "usual care". All had cervical squamous cell carcinoma of stage I, II, or III, were 9 to 24 months after diagnosis and displayed psychological (dis)stress as measured on the Brief Symptom Inventory scale.
The PTC consisted of 6 sessions designed to help cope with the distress of cervial cancer. They included a "psychosocial interview (on) managing stress and emotions, enhancing health and wellness, and addressing relational and sexual concerns" followed by a "1-month booster session".
This is a more complex study as it looks at different types of telomeres and changes in naive T cells, although it does less on comparing interventions. The chart at left shows that as BSI stress (vertical axis) decreased, the telomere length (horizontal axis) increased, consistent with the Carlson paper.
Ornish, et al. did a study on lifestyle changes, telomerase (which elongates telomeres), and stress in low-risk prostate cancer, with positive results, but it was not control-based and TLs were not measured.
Shortened telomeres were found in many studies in premalignant tissues and in tissue adjacent to tumors supporting the belief that this leads to early cancinogenesis as well as increases in the incidence and mortality from malignancies.
Shortened TLs have been linked in many studies to chronic psychological stress as well as "disease progression" in many chronic diseases, including cardiovascular disease. There is much research demonstrating that psychological stress is associated with increased cancer development, progression and mortality in both humans and animals.
Like most "first" studies, it is clear that larger populations over longer times are needed to improve the statistics, but it is clear from these studies that cancer survivors experience severe stress, and that meditation, group therapy and coping techniques lower that stress which increases the chance of survival, which can be tracked by a widely-accepted biomarker.
a) "Mindfulness-Based Cancer Recovery" (MBCR) developed by two of the authors, Linda Carlson and Michael Speca of the Oncology Department @ the University of Calgary
b) supportive-expressive group therapy (SET)
c) a 6-hr stress management seminar for controls
As described in the post above, and in "mindfulness meditation - religious vs secular - does it work? - new research", Jon Kabat Zinn's "Mindfulness-Based Stress Reduction" (MBSR) was the key to unlocking the power of mindfulness meditation by moving to a secular, scientifically-validated approach.
MBCR is based heavily on MBSR but tailored for cancer patients. The book on MBCR is even entitled "Mindfulness-Based Cancer Recovery: A Step-by-Step MBSR Approach to Help You Cope with Treatment and Reclaim Your Life".
The 92 participants in the study met four requirements:
a) Completed all medical treatments three months previously
b) Diagnosed with AJCC stage I to III breast cancer
c) Over 18 years old
d) Scored over 4 on the National Comprehensive Cancer Network Distress Thermometer
The MBCR group attended 8 weekly group sessions of 90 minutes, a six-hour retreat, and got a course booklet and CDs for guided meditation and mindful body movement at home. The SET group met for 90 minutes weekly for 12 weeks. Both MBCR and SET had comparable structure, group size, environment and contact time.
T/S is the ratio between the length w/the telomere to the "single-copy gene length". Both MBCR and SET maintained the T/S ratio over the 3 month intervention period. However, the control population had decreased TLs.
This confirmed the Carlson's group earlier study. As the report states "...this finding adds to the literature supporting the potential for stress-reducing interventions to impact important disease-regulating processes and ultimately disease outcome."
There is only one other control-based study on associations between chronic stress levels, TL and cancer. It was done earlier on cervical cancer by Biegler, et al. in 2012 in Cancer Prevention Research @ UC Irvine.
 |
| Edward Nelson UC Irvine Group leader |
The Nelson group did several studies with cervical cancer survivors using a "culturally-sensitive psychosocial telephone counseling intervention" (PTC) which produced "significantly improved QOL as well as modulation of stress-associated biomarkers".
This study had only 22 participants; 10 received PTC, the rest "usual care". All had cervical squamous cell carcinoma of stage I, II, or III, were 9 to 24 months after diagnosis and displayed psychological (dis)stress as measured on the Brief Symptom Inventory scale.
The PTC consisted of 6 sessions designed to help cope with the distress of cervial cancer. They included a "psychosocial interview (on) managing stress and emotions, enhancing health and wellness, and addressing relational and sexual concerns" followed by a "1-month booster session".
 |
| Stress (v) vs Telomere length (h) |
Ornish, et al. did a study on lifestyle changes, telomerase (which elongates telomeres), and stress in low-risk prostate cancer, with positive results, but it was not control-based and TLs were not measured.
Shortened telomeres were found in many studies in premalignant tissues and in tissue adjacent to tumors supporting the belief that this leads to early cancinogenesis as well as increases in the incidence and mortality from malignancies.
Shortened TLs have been linked in many studies to chronic psychological stress as well as "disease progression" in many chronic diseases, including cardiovascular disease. There is much research demonstrating that psychological stress is associated with increased cancer development, progression and mortality in both humans and animals.
Like most "first" studies, it is clear that larger populations over longer times are needed to improve the statistics, but it is clear from these studies that cancer survivors experience severe stress, and that meditation, group therapy and coping techniques lower that stress which increases the chance of survival, which can be tracked by a widely-accepted biomarker.
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