[Rheumatic diseases and multimorbidity]

In the past decade, investigators' undeniable and justified interest has not been fading in comorbidities in the presence of rheumatic diseases. The terms "comorbidity" and "multimorbidity" are frequently and not always consciously used as interinterchangeable, confusing the terminology and accordingly the elaboration of strategies for further researches. The concepts "(co-occurring disease" and "multimodality" are not mutually exclusive or contradictory, but these should be considered from another point of view than "comorbidity". The problem of multimorbid disease is the rule rather than the exception for clinicians treating primarily "typical" rheumatic patients. Recent researches could outline a few key areas for further study of the concept of multimorbidity in rheumatologic practice, which will be able to turn the international research community from rheumatic disease to the patient as a whole.