Quote from: pynetx on August 31, 2018, 09:23:14 AM

Quote from: nkryuchkov on August 31, 2018, 06:23:23 AM

Hi everyone!

EHF Advisor, prof. Arnold Mitnitsky answers questions about aging, frailty index, longevity, mathematical models that help to understand and fight against aging.

Take a look at the 2nd part of his comments.

4. How aging could be measured?
Aging could be measured in many ways at the different levels. Our approach is to sum up multiple health attributes of the various nature (for simplicity, they should be dichotomized). The fraction of health deficits from the total number of health attributes (known as a frailty index or FI) is associated with multiple adverse outcomes (mortality, length or stay in hospital, morbidities). Thus, the FI is a useful (and holistic) utility measure that represents the state of health of the entire organism. There are several other measures that are in some use although not as widespread as the FI. One such measure is the DNA Methylation age that is based on the characteristics of epigenetic system. The other measures of the rate of aging, i.e. the different indices of biological age based on the batteries of biomarkers (e.g., obtained from the blood tests). The comparison of these measures has yet to be done in order to understand the advantages and limitation of each of them.

5. What about Frailty Index?
The frailty index (FI) is a measure of health of individuals (health utility) based on the accumulation of deficit approach. The FI is the ratio of health deficits present in an individual to the total number of deficits available in the database or in the study. The FI lies between 0 (no deficits present) to 1 (all deficits present) although empirical limit of the FI is close to 0.7 the higher values of FI are incompatible with life. The frailty index is a robust predictor of adverse outcomes, such as mortality, and increasingly used in many epidemiological and clinical studies. The term includes frailty to reflect the vulnerability to stresses during the aging process, and index reflects the degree of such vulnerability. The FI should not be confused with the Frailty Phenotype which is a simple tool constructed from 5 characteristics of physical functioning although less comprehensive and less powerful than the FI. The FI is a measure of the global damage of the organism, it is not only empirically validated in multiple settings but also has a strong theoretical support in the new complex dynamical network model of aging and frailty developed by our group.

6. Why math models could help us fighting aging?
Mathematical modeling become increasingly popular in many areas of science and technology. There is a strong needs for that. In general, mathematical modeling is a central part of the theoretical advances in science. As people say: Nothing is more practical than a good theory (Kurt Lewin). As for controlling /postponing/ slowing aging (that I would prefer to fighting aging, combating aging, and such) the mathematical model is the only thing that allows to understand the processes under investigation, especially the processes involved the complex interactions and nonlinearities, like aging. Without modeling, what we have instead would be a bunch of semantical statements without the possibility to be tested (or falsified). If we do understand the aging process we can do something to modify it. Otherwise, we will be drown in the deep and murky waters of complexity and to fight with each other, instead of fighting aging (as often goes and goes on).

Could you please provide the link for the first part of this question/answer session?

https://bitcointalk.org/index.php?topic=2577450.msg44016624#msg44016624

This is the link to the first part.