Quantifying the Assertion that Some Older People are in Better Shape than Others
It is undeniably the case that some older people are in relatively good shape when compared to their peers, and even when compared to individuals a decade or two younger. Aging is a process of damage accumulation, and thus you don't get to have a longer life expectancy in later life without being in better shape. In earlier old age a majority of the difference is made by lifestyle choices, but the longer you live the more of the difference becomes genetic in nature, the degree to which your physiology can resist or accommodate various forms of damage. Over the last decade researchers have increasingly worked to quantify exactly how the older people with better health are different from those who suffer more and die younger. This is all interesting work, but actually of little relevance to the future of human longevity. When, in the years ahead, clinics can repair the damage that causes aging, no-one will ever get to the point at which genetic differences and the ability to soldier on while very damaged become significant. Learning how a damaged system can better operate is really nowhere near as important as learning how to repair the damage.
In a pilot study on some of the oldest people of the world, researchers discovered that the perfusion of organs and muscles of the centenarians was as efficient as that in people who were 30 years younger. Results of the CIAO (Cilento Intitiative on Aging Outcome) pilot study suggest that low blood levels of the peptide hormone adrenomedullin (bio-ADM) are an indicator for such a good microcirculation. Making longevity measurable has long been a scientific goal as it could open up the avenue to a systematic identification of factors contributing to an extended life span.
The team carried out comprehensive health and life style assessments of two study groups that live in the Cilento region, located in the province of Salerno in southern Italy: In the first were 29 so-called 'SuperAgers' (median age 92 years), while the second was made up of 52 younger relatives (median age 60 years, living in the same household) who are expected to live just as long because they have the same genetic background and have been exposed to the same environmental and lifestyle factors. Blood biomarker analyses measured levels of the heart-function biomarker MR-proANP, as well as a marker for kidney function (penKid) and bio-ADM. The last is a regulator of vasodilation and blood vessel integrity, which both affect blood pressure. The results were compared to those of a cohort of 194 healthy persons (median age 63.9 years), who were monitored over eight years in the earlier Malmö Preventive Project (MPP).
As expected, low values of MR-proANP and penKid among the subjects in the two younger control groups indicated no signs of heart or kidney dysfunction. In contrast, both biomarkers were elevated in the SuperAgers, possibly due to the process of organ aging. However, even though the older group had levels of the two biomarkers that were as high as those found in patients experiencing heart failure (HF) or acute kidney injury (AKI), they were in clinically good condition. Surprisingly, in the group of SuperAgers, the bio-ADM values - which are often pathologically elevated in HF or AKI patients - were as low as those in both reference groups. Very low concentrations of this biomarker indicate a well-functioning endothelial and microcirculatory system allowing good blood perfusion of organs and muscles. A good microcirculation is what makes marathon runners perform better at the same heart rate than the average man or woman on the street.
Link: http://www.eurekalert.org/pub_releases/2016-09/sg-gmi_1090216.php