ABC of Multimorbidity
ABC of Multimorbidity
Martin Fortin 1, Stewart W. Mercer 2, and Chris Salisbury 3
1Family Medicine Department, Université de Sherbrooke, Centre de Santé et de Services Sociaux de Chicoutimi, Canada
2General Practice and Primary Care, Institute of Health and Wellbeing, University of Glasgow, UK
3Centre for Academic Primary Care, NIHR School for Primary Care Research, School of Social and Community Medicine, University of Bristol, UK
Multimorbidity refers to the presence of several co-occurring long-term conditions, being related or not, in a given patient
Comorbidity refers to any additional condition that may occur during the clinical course of a patient who has an index condition that is the focus of interest
Different terms such as frailty, disability and complexity are used by clinicians and researchers to describe conditions that are related to multimorbidity, representing different concepts
Multimorbidity is not a medical diagnosis with well-defined criteria but represents nonetheless a major challenge for patients and clinicians, and is an emerging priority for healthcare systems. Background
Improvements in public health and advances in the provision of health care have contributed to an increased life expectancy. People affected by medical conditions that previously led to premature death can now survive much longer. Therefore, as the population ages, an increasing number of people are now living with long-term medical conditions. Furthermore, it is now recognized that many people have multiple long-term conditions, a state which we refer to in this book as 'multimorbidity'.
First, we need to consider some issues of terminology and definition. The concept of multimorbidity is quite easy to understand in general terms, but quite hard to define, with many people using the same term to mean different things. Furthermore, the concept of multimorbidity is related to, but distinct from, other related terms such as comorbidity, complexity and frailty. From a medical diagnostic perspective, the terms comorbidity and multimorbidity have sometimes been used interchangeably, which is misleading. This chapter introduces the concepts of comorbidity and multimorbidity and differentiates them from other related concepts frequently used by clinicians and researchers (see Figure 1.1 ).
Figure 1.1 Conceptual diagram of comorbidity.
Adapted from: Boyd CM and Fortin M. 2011.
What is the difference between multimorbidity and comorbidity?
How do the concepts of multimorbidity and frailty differ?
What are the two minimal components of a simple operational definition of multimorbidity?
Feinstein, in his seminal paper published in 1970, is credited for recognizing that the therapeutic outcome of an index disease may vary depending on the type and nature of other accompanying disorders. He coined the term comorbidity: 'any distinct additional clinical entity that has existed or that may occur during the clinical course of a patient who has the index disease under study'. In the 1980s and 1990s, some authors (mostly Germans publishing articles in English) started using the word multimorbidity when referring to patients with multiple simultaneous conditions without considering any one as the index condition. The existence of other equivalent terms for multiple concurrent conditions in the medical literature ( Table 1.1 ) has led to ambiguity and inconsistency in their use.
Table 1.1 Terms used to designate multiple conditions.