[Managing multimorbidity is more than counting the number of conditions]

The prevalence of patients with multimorbidity, defined by two chronic conditions is rapidly increasing. Defining multimorbidity remains challenging, with varying criteria in research. A recent study by MacRae et al. examined the impact of the number and selection of conditions on estimated multimorbidity prevalence, revealing significant variations from 4.6% to 40.5%. To standardize the definition for research, MacRae et al. recommend using three measurement instruments (Ho always + usually, Barnett, or Fortin condition-lists) to consistently measure prevalence over time. Multimorbidity's complexity is not adequately captured by dichotomous definitions, as this depends on context and purpose. Chronic diseases profoundly affect daily life, leading to reduced physical function and adverse psychosocial outcomes. Patients often experience increased stress, anxiety, and depression, which can further exacerbate somatic conditions. To assess multimorbidity from a patient perspective, considering experienced health and quality of life indicators like ADL functioning, mobility, mood, memory, and social factors is crucial. Effectively managing multimorbidity requires a holistic, tailored approach, including identifying and prioritizing key health issues, promoting self-management, proactive care planning, and coordinating treatments. Understanding the potential for differential treatment effects and considering individual life expectancy is vital. Multimorbidity also places a significant burden on healthcare systems, leading to fragmented care, communication gaps, and increased costs. Identifying complex disease clusters with high mortality and resource utilization can guide integrated care efforts. In less complex cases, primary care physicians can collaborate to provide comprehensive care. Multimorbidity remains a priority in healthcare, necessitating appropriate measurement and tailored interventions for diverse populations.