New study below. [1]
I think it clarifies claims that "fat" has a survival value - which contradicted many studies that found higher BMI to be risk factor.
It has long been recognized that the body mass index [BMI] is a poor surrogate for visceral fat. Visceral fat - including periprostatic fat - is hormonally active & favors PCa proliferation. Subcutaneous fat is not active.
Certain "healthy" high-carb diets lead to a good BMI, but with fat around internal organs. Only a scan can tell how much fat is hidden away. It's also possible for a man to have little or no visceral fat, but an overweight BMI profile.
The meta-analysis found that high muscle mass and subcutaneous adipose tissue was associated with overall survival. (castrate testosterone levels tend to lead to a loss of muscle mass)
Importantly, IMO, low visceral:subcutaneous adipose tissue ratio was associated with overall survival in men with prostate cancer.
IMO, the key to visceral fat uptake is triglycerides. The triglycerides: HDL-cholesterol ratio is a reliable surrogate for insulin resistance.
A rule of thumb for triglicerides is that >=150 is bad; <100 is good.
& for the Tri:HDL-C ratio: >=2:1 is bad; 1:1 is very good.
-Patrick
[1] pubmed.ncbi.nlm.nih.gov/344...
Review Prostate Cancer Prostatic Dis
. 2021 Aug 21. doi: 10.1038/s41391-021-00442-0. Online ahead of print.
Associations of fat and muscle mass with overall survival in men with prostate cancer: a systematic review with meta-analysis
Pedro Lopez 1 2 , Robert U Newton 3 4 5 , Dennis R Taaffe 3 4 , Favil Singh 3 4 , Laurien M Buffart 3 6 , Nigel Spry 3 4 7 , Colin Tang 3 4 8 , Fred Saad 9 , Daniel A Galvão 3 4
Affiliations collapse
Affiliations
1 Exercise Medicine Research Institute, Edith Cowan University, Joondalup, WA, Australia. p.lopezdacruz@ecu.edu.au.
2 School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia. p.lopezdacruz@ecu.edu.au.
3 Exercise Medicine Research Institute, Edith Cowan University, Joondalup, WA, Australia.
4 School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.
5 School of Human Movement and Nutrition Sciences, University of Queensland, St. Lucia, QLD, Australia.
6 Department of Physiology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands.
7 Faculty of Medicine, University of Western Australia, Nedlands, WA, Australia.
8 Department of Radiation Oncology, Sir Charles Gairdner Hospital, Perth, WA, Australia.
9 Division of Urology and Urologic Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.
PMID: 34420038 DOI: 10.1038/s41391-021-00442-0
Abstract
Background: To systematically review and analyse the associations between fat and muscle mass measures with overall survival in men with prostate cancer.
Methods: A systematic search was conducted in CINAHL, Cochrane Library, EMBASE, PubMed, and Web of Science databases from inception to December 2020, while abstracts from the American Society of Clinical Oncology (ASCO), Clinical Oncology Society of Australia (COSA), and the American College of Sports Medicine (ACSM) conferences were searched from 2014 to 2020. Eligible articles examined the association of body composition measures, such as fat mass (e.g., fat mass, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT) and muscle mass measures, with overall survival in prostate cancer patients at any treatment stage. The primary endpoint was overall survival. Random-effect meta-analysis was conducted for studies reporting multivariable or univariable analysis assessing the associations of fat mass measures (i.e., fat mass, VAT, SAT, VAT/SAT) and muscle mass measures with overall survival.
Results: Sixteen cohort studies that comprised 4807 men with prostate cancer were included. Total adiposity (hazard ratio (HR) 0.98, 95% CI: 0.75-1.28, p = 0.888) and VAT (HR 1.03, 95% CI: 0.74-1.43, p = 0.873) were not significantly associated with overall survival, while higher subcutaneous adipose tissue levels were associated with higher survival (HR 0.68, 95% CI: 0.54-0.84, p = 0.001). Greater mortality risk was found in patients with localised (HR 1.91, 95% CI: 1.40-2.62, p < 0.001) and advanced disease (HR 1.43, 95% CI: 1.07-1.92, p = 0.020) presenting with low levels of muscle mass compared to those presenting with high levels.
Discussion: These results indicate that although overall adiposity should be cautiously interpreted in regards to survival, high muscle mass and SAT, and low VAT/SAT ratio values are associated with overall survival in men with prostate cancer.
© 2021. The Author(s).