Bringing complexity into clinical practice: An internistic approach.

Modern medicine, still largely focused on single diseases, is unprepared for managing clinical complexity (CC), which is an emerging issue. Ageing of the general population has favoured the occurrence of chronic diseases, which generate multimorbidity that has been considered for many years the main feature of CC. However, more recent studies have shown that CC is something more and different and originates from the dynamic interaction among the patient's intrinsic factors (age, gender, multimorbidity, frailty) as well as contextual factors (socioeconomic, behavioural, cultural, and environmental). The result of these interactions is non-linear and unpredictable behaviour, which is difficult to manage both in clinical practice and in the organisation of care. Up to now, the prevalent approach has consisted of breaking down and separately analysing each CC component. Consequently, only incomplete strategies to improve health outcomes have been developed, such as limited patient-centred algorithms, deprescription of therapies, and local clinical governance interventions. Medical education has a pivotal role in transmitting the knowledge of complexity, making it realistically understandable and manageable. Future research should aim at implementing our knowledge of CC, developing new tools for its quantitation, and finding new solutions to improve important health outcomes at a sustainable cost.