A researcher here runs the numbers to demonstrate an inverse correlation between autoimmune disease incidence and life expectancy. It is interesting to speculate on the mechanisms here, which are probably not going to turn out to be a straightforward matter of (a) declining immune function being important in the progression of aging, and (b) more autoimmunity indicating a greater tendency to subclinical immune dysfunction over the course of aging in a population:
The autoimmune diseases are among the ten leading causes of death for women and the number two cause of chronic illness in America. They are a predisposing factor for cardiovascular diseases and cancer. Patients of some autoimmune diseases have shown a shorter lifespan and are a model of accelerated immunosenescence. Centenarians from the other side, are used as a model of successful aging and have shown better preserved several immune parameters and lower levels of autoantibodies. My study is focused on clarifying the connection between longevity and some autoimmune and allergic diseases in 29 developed OECD countries as the multidisciplinary analyses of the accelerated or delayed aging data could show a distinct relation pattern, help to identify common factors and determine new important ones that contribute to longevity and healthy aging.
I have assessed the relations between the mortality rates data of Multiple Sclerosis MS, Rheumatoid arthritis RA, Asthma, the incidence of Type 1 diabetes T1D from one side and Centenarian Rates (two sets) as well as Life Expectancy data from the other side. The obtained data correspond to an inverse linear correlation with different degrees of linearity. I have been the first to observe a clear tendency of diminishing Centenarian Rates or Life Expectancy in countries having higher death rates of Asthma, MS and RA and a higher incidence of T1D in children. I have therefore concluded that most probably there are common mechanistic pathways and factors, affecting the above diseases and in the same time but in the opposite direction the processes of longevity. Further study, comparing genetic data, mechanistic pathways and other factors connected to autoimmune diseases with those of longevity, could clarify the processes involved, in order to promote the longevity and limit the expanding of those diseases in the younger and older population.