Multimorbidity
Definition
Multimorbidity is the presence of two or more chronic health conditions in the same person. These conditions may be physical, mental, or both, and they can interact in ways that make care, prevention, function, and quality of life more complex than treating each condition separately. [1] [2] [3]
Why It Matters in Ageing Research
Multimorbidity matters because the risk of living with multiple chronic conditions rises with age and is closely linked to disability, frailty, medication burden, healthcare use, mortality risk, and reduced healthspan. In longevity research, multimorbidity is important because ageing biology may contribute to several diseases at once, rather than to one disease in isolation. This makes it a useful outcome for studying whether interventions affect broad ageing-related risk rather than a single diagnosis. [2] [4] [5]
Common Confusion
- Multimorbidity is not the same as comorbidity, which usually frames one condition as the primary disease and others as additional conditions.
- Multimorbidity is not just a count of diagnoses; the specific combination and severity of conditions matter.
- Having multiple conditions does not mean they all have the same cause, but shared ageing mechanisms may influence risk across systems.
Related Reading
References
- van den Akker, M., Buntinx, F., & Knottnerus, J. A. (1996). Comorbidity or multimorbidity: What's in a name?. https://pubmed.ncbi.nlm.nih.gov/8911007/
- World Health Organization. (2016). Multimorbidity: Technical Series on Safer Primary Care. https://iris.who.int/handle/10665/252275
- The Academy of Medical Sciences. (2018). Multimorbidity: A priority for global health research. https://acmedsci.ac.uk/file-download/82222577
- Barnett, K., et al. (2012). Epidemiology of multimorbidity and implications for health care, research, and medical education. https://pubmed.ncbi.nlm.nih.gov/22579043/
- Fabbri, E., et al. (2015). Aging and multimorbidity: New tasks, priorities, and frontiers for integrated gerontological and clinical research. https://pubmed.ncbi.nlm.nih.gov/25724969/
This glossary entry is provided for educational purposes only and does not constitute medical advice.