The term 'comorbidity' was introduced in medicine by Feinstein (1970) to denote those cases in which a 'distinct additional clinical entity' occurred during the clinical course of a patient having an index disease.
Mõiste "komorbiidsus" võttis meditsiinis kasutusele Feinstein (1970), et tähistada neid juhtumeid, kus "erinev täiendav kliiniline üksus" leidis aset patsiendi indekshaiguse kliinilise kulu kestel.