Comorbidity, clinical complexity and palliative care
Venue: Internal and Emergency Medicine
Year: 2020

We understand comorbidity as the association of two diseases in one patient at a higher rate than expected by chance. A person centered approach is not possible without analyzing the comorbidities that a patient presents. Comorbidity occurs in 79% of all sick people. Clinical complexity is a protean term that encompasses multiple levels and domains; it includes all the disorders and conditions experienced by a person in transversal and longitudinal contexts, not only the diversity of severity levels and courses of clinical conditions, but also the plurality of values of people who experience health problems and seek help for them. There is no doubt that the relevant social and financial conditions should also be considered in the evaluation of the patient's clinical complexity  The coexistence of long term medical conditions is very common and is expected to increase as population's age. People with multimorbidity are the main users of health services, and account for about two thirds of the cost of medical care. They require more complex care, usually take multiple drugs and receive fragmented medical care. Multimorbidity increases the risk of hospitalization, the adverse effects of treatment or polypharmacy, high costs of medical care, reduced quality of life and increased mortality. Unlike comorbidity, where additional health conditions are considered secondary to a primary diagnosis, the conceptualization of multimorbidity does not give primacy to any condition ahead of others, but sees the patient's health conditions as a holistic set  Clinical complexity represents one of the main challenges of modern medicine. Health organizations are not equipped or oriented to serve it. Common therapeutic and diagnostic medical approaches focus on each disease and do not consider the interactions between diseases and medications that affect health and functional outcomes. Clinical practice suggests that the complexity of the patient is an interaction between medical problems, psychological and social characteristics and factors of Health. To try to evaluate the clinical complexity, different instruments have been proposed. The number of comorbidities (NoC) was considered a marker of clinical complexity. However, this instrument would not give information on the clinical relevance of each condition. In contrast, the cumulative disease rating scale (CIRS) addresses the problem by calculating both the CIRS severity index (CIRS SI) and the CIRS comorbidity index (CIRSCI) The RePoSI registry, an Italian multicenter study, collects a representative sample of hospitalized elderly patients from different centers. A recent analysis points out the meaning and importance of the CIRS assessment of comorbidities compared to NoC in a relevant subset of internal medicine patients  Using the total number of chronic diseases represents an easy measure to define the health burden but does not consider the types of diseases present, while focusing on a particular disease and its comorbidities is more useful. Some studies have used a comorbidity count (Charlson) that includes the weights of multiple diseases but does not provide disease patterns and patient risks. Other studies have used factor analysis to classify multiple diseases or to define groups by prevalence. All these methods have helped classify patterns at a specific point in time. However, categorization may not follow the same pattern over time. The prognosis regarding the quality of life and the dynamics of multimorbidity remains a challenge. In general, the approach to multiple chronic diseases can be classified in two ways: the disease centered approach or the personcentered approach. The person centered approach provides information on the high risk population and disease patterns within a certain group of people. One study examined the multimorbidity trajectories of chronic diseases among Taiwanese elders over a period of 14 years. Related factors included age, education level, physical functioning, depressive symptoms and health exams and these factors appear to be valid in all nationalities  Fernando Miguel Gamboa Antinolo minfga@us.es; fernandom.gamboa.sspa@juntadeandalucia.es