Last reviewed 01/2018

Multimorbidity can be defined as the co-occurence of two or more long term conditions in an individual (1).

  • this is an operational definition and the cut-off count of the number of conditions may vary according to the author (three, four or five long term conditions).  For clinical purposes, patients with multiple long term conditions (without a specific number) are considered to be multimorbid (2)

  • it is considered to be associated with decreased quality of life, lower physical function, psychological distress and polypharmacy (1)
    • a survey (with 7620 patients) done in the primary care setting in Australia has reported that depression was present in 23% of patients with one chronic condition compared with 40% of those with five or more conditions.   

It is important to differentiate mulitmorbidity from co-morbidity which refers to conditions that exist with an index condition which is the focus of interest (2).
Multimorbidity is associated with greater use of healthcare.

  • around 80% of the GP consultations are for multimorbidity (2)

A systemic review of 11 studies carried out on patterns of multimorbidity revealed:

  • that the most common pair of conditions observed was osteoarthritis and a cardiometabolic condition (hypertension, diabetes, obesity, or ischaemic heart disease)

  • three common factors across combinations of conditions - cardiometabolic condition factor, a mental health condition factor (most commonly depression or anxiety), and a painful condition factor (1)

NICE state with respect to multimorbidity:

Multimorbidity is usually defined as when a person has 2 or more long-term health conditions

  • multimorbidity refers to the presence of 2 or more long-term health conditions, which can include:
    • defined physical and mental health conditions such as diabetes or schizophrenia
    • ongoing conditions such as learning disability
    • symptom complexes such as frailty or chronic pain
    • sensory impairment such as sight or hearing loss
    • alcohol and substance misuse

  • measuring the prevalence of multimorbidity is not straightforward because it depends on which conditions are counted. However, all recent studies show that multimorbidity is common, becomes more common as people age, and is more common in people from less affluent areas

  • in older people multimorbidity is largely due to higher rates of physical health conditions, in younger people and people from less affluent areas, multimorbidity is often due to a combination of physical and mental health conditions (notably depression)