The Character and Destination of Multimorbidity: Reflections for Classification

one of the main challenges of medicine and epidemiology is the approach to multimorbidity. But, the natural history of multimorbidity is unknown. Health problems are complex structures. None appears isolated, free from relationships and accurate and clear. An evolution of the “order-disorder-order” type that can be observed in an isolated health problem is not fulfilled in multimorbidity. Are health problems, in multimorbidity, concurrent lines that start from different places but end at the same point, or are they divergent, or parallel lines? Are there several storylines at the same time which are interwoven and where there is no final outcome? Is invariably predetermined the destiny of the grouping of several diseases in the first days or months of an evolution that lasts many years? Are the accumulation of diseases combinations: where the order of problems does not matter or permutations: where the order does matter? Are there “good problems” and “bad problems”? Do health problems / diseases have an evolution that leads to an outcome to reach a destination that is “victory or failure”, or the evolution of problems does not present any purpose and there is not really evolution, but consumes its time? Does the accumulation of diseases tend to disorganization or can they lead to a higher order? Attempting to answer these questions and approach the classification of the character and destiny of multimorbidity can help to understand and address it.

Keywords: Multimorbidity; Complexity; Framework; Natural History of Disease.