Traditional wisdom about chronic diseases holds that they usually last for three months or longer and may worsen over time.  They are supposed to occur more in older adults and can usually be controlled but not cured.

Conditions, which we thought worsen with age, paradoxically provide some protection.

As with preventable disease, identifying risks early in life and instigating lifelong preventive treatment has always been the holy grail of medicine. For example, everybody would prefer to treat high blood pressure for a lifetime rather than suffer from a heart attack or a stroke later on.

Paradoxically, however, the more we learn about our bodies, the more we understand that diseases do not progress in a linear fashion. There is well established evidence that certain chronic diseases, such as depression, multiple sclerosis and periodontal (gum) disease, come and go cyclically.

Now we are discovering that conditions we thought worsen with age surprisingly instead provide some protection. For example, higher cholesterol and higher triglycerides seem to extend life after the age of 65. Similarly, evidence is now emerging that mildly high blood pressure has no effect in shortening life expectancy in the over 65-year-old age group. In the same age group obesity has no effect on how long we live. The list goes on: suffering from renal disease requiring dialysis, chronic heart failure, rheumatoid arthritis, or HIV have no effect on how long we live as we get older.

The phenomenon of established risk factors and diseases having a markedly different and even opposite effect on mortality pattern in older persons is paradoxical. The current explanation is that as we age, we acquire a range of chronic diseases that deplete our internal resources. Hence, as our bodies fight these diseases, we are more likely to be under nourished than over nourished.

As simple pictures of disease become more complex, the blanket guidance and data-driven protocols health services follow will be less able to deliver effective care for individuals. Clinicians of the future will need to be comfortable dealing with their own uncertainties before attempting to engage in partnerships with patients.  They will need to divorce themselves from their traditional training about the path of diseases to provide quality care.