Great effort is required to arrest decay and restore vigor. One must exercise proper deliberation, plan carefully before making a move, and be alert in guarding against relapse following a renaissance.
Quintus Horatius Flaccus, (Horace) 20 BCE14
It is also necessary to mention the interactions between different diseases or conditions within a patient, usually referred to as comorbidity. Comorbidity is not easy to define; it takes into account the temporal sequences with respect to both diagnosis and progression, and the interactions between the diseases with respect to possible common causality, for example genetic factors, and treatment influences with respect to drug interactions. Nevertheless, we might expect that comorbidities have a profound influence on The Inflection Point and the slopes and irregularities of the quality profile curves. Ultimately these may be the determining factors that control end-of-life decisions; for example, the incidence of chronic kidney disease is 150% higher for those who are visually impaired than those who are not.
It is difficult to know how to treat comorbidities since there are so many unknowns and so many permutations. I will deal with it only when there is something definitive to say; in such circumstances where factual conclusions are hard to identify, I usually rescue myself by writing a poem:
There is grey matter and white matter
White fat and brown fat
Red cells and white cells
Shouldn’t they all cross the finish line
Together, when we go?
No, they take it in turns
Some bone cells today
You walk a little less
Retinal cells tomorrow
We see a little less
Arteries blocking slowly
Makes breathing labored
Are we close to that line?
No, not yet
A disc slips one way
Pinching a nerve as it goes
A sphincter gets looser
No one wants to know
Why can’t they go at once
So we prepare for our maker
In one healthy piece
Then painlessly say goodbye
Because the brain and the heart
Do not agree with each other
Don’t work together, never did
Mind and matter
Body and soul