Muscle and cancer - It is not getting old that is the problem, it is getting weaker!

I saw this get picked up in a few places but no one was linking to the actual study.  The takeaway message is that building and maintaining muscle strength is vital to all for overall health and this extends to surviving cancer.  It is not getting old that is the problem, it is getting weaker!

Researchers studied patients with advanced melanoma to understand the illness as it related to muscle strength. They looked at CT scans of the psoas muscle in order to measure core muscle density. The authors then correlated the core muscle density with the risk of metastasis, or spreading of the cancer. 

Patients with higher muscle density were found to have significantly better survival rates and less metastasis.  The authors concluded that decreased muscle density was an important predictor in the outcome of the disease. Furthermore, they stated that “frailty, not age, was associated with decreased disease-free survival.”

Here is theabstract

Sarcopenia as a Prognostic Factor among Patients with Stage III Melanoma.

Abstract

BACKGROUND: Several hypotheses proposed to explain the worse prognosis for older melanoma patients include different tumor biology and diminished host response. If the latter were true, then biologic frailty, and not age, should be an independent prognostic factor in melanoma.

METHODS: Our prospective institutional review board (IRB)-approved database was queried for stage III patients with computed tomography (CT) scans at time of lymph node dissection (LND). Psoas area (PA) and density (PD) were determined in semi-automated fashion. Kaplan-Meier (K-M) survival estimates and Cox proportional-hazard models were used to determine PA and PD impact on survival and surgical complications.

RESULTS: Among 101 stage III patients, PD was significantly associated with both disease-free survival (DFS) (P = 0.04) and distant disease-free survival (DDFS) (P = 0.0002). Cox multivariate modeling incorporating thickness, age, ulceration, and N stage showed highly significant association with PD and both DFS and DDFS. DDFS was significantly associated with Breslow thickness (P = 0.04), number of positive nodes (P = 0.001), ulceration (P = 0.04), and decreasing muscle density (P = 0.01), with hazard ratio of 0.55 [95% confidence interval (CI) 0.35-0.87]. PD also correlated with surgical complications, with odds ratio (OR) of 1.081 [95% CI 1.016-1.150, P = 0.01]. 

CONCLUSIONS: Decreased psoas muscle density on CT, an objective measure of frailty, was as important a predictor of outcome as tumor factors in a cohort of stage III melanoma patients. On multivariate analysis, frailty, not age, was associated with decreased disease-free survival and distant disease-free survival, and higher rate of surgical complications.

Reasons to get moving...

First, a music video. What else but...?


Part 1. Get slimmer.
Insulin increases the amount of nutrients entering adipocytes, which makes us fat and hungry.

Er, just a minute!

If increasing the amount of nutrients entering cells makes us hungry, exercise (which increases the amount of nutrients entering muscle cells) would make us hungry. It doesn't. See Fig. 1. in Influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin, and peptide YY in healthy males.

If going for a walk outdoors makes you hungry, you're doing it wrong. Wrap up warm, as feeling cold increases hunger. Low blood glucose level also increases hunger, so don't over-exercise while on a long-term ketogenic diet.

By the way, insulin also increases the amount of nutrients entering muscle cells.
Q. What determines the relative amounts of nutrients entering adipocytes vs muscle cells?
A. The relative insulin sensitivities of adipocytes vs muscle cells.

Adipocytes are sensitive to insulin until they become full. To reduce the amount of nutrients entering adipocytes, divert more nutrients to muscle cells by increasing their insulin sensitivity. Emptying muscle cells by doing low-intensity exercise increases their insulin sensitivity. High-intensity exercise increases their insulin sensitivity.


Part 2. Prevent/reverse age-related sarcopenia (muscle loss).
See Use 'em or lose 'em. As diverting more nutrients to muscle cells increases muscle mass, increasing their insulin sensitivity results in increased muscle mass, unless you're eating way below maintenance calories. High-intensity exercise results in more muscle mass gain than low-intensity exercise.


Part 3. Make your brain work properly.
Thanks to Chris Highcock, who gave me a complimentary copy of Hillfit, I found IL-6 and IL-10 Anti-Inflammatory Activity Links Exercise to Hypothalamic Insulin and Leptin Sensitivity through IKKβ and ER Stress Inhibition.

In plain English, this means that exercise increases both insulin and leptin sensitivity in the hypothalamus. As the hypothalamus controls appetite and both insulin & leptin are appetite-suppressing, the net result is less appetite.

Use 'em or lose 'em

Hello world. I'm back. The title is referring to our muscles. The following image is from Figure 1 of Chronic Exercise Preserves Lean Muscle Mass in Masters Athletes.




I'm not going to start doing chronic exercise, but the above is a great incentive to continue with the walking.