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Clinical Evidence for the Brave New World on Multimorbidity

12 Mar, 15 | by BMJ Clinical Evidence

by Victor Montori

The most common chronic condition worldwide is, or will soon be, multimorbidity. Previously a concern reserved to the very old, multimorbidity increasingly affects younger people. A prevalence study in Scotland found that the average middle age person is no longer a healthy one, but a patient with at least one chronic condition; 1 in 4 had two chronic conditions. As the population ages, the proportion with multimorbidity approaches universality. As the evidence, often obtained in people with a paucity of comorbidities, gets incorporated into practice guidelines, guideline panels face a key task. Their task is often to provide recommendations on the management of a single chronic condition. So multiple panels take on the task of doing so, each for “their” condition. This approach delegates to front-line clinicians and patients the task of sorting out which recommendations to follow given the priorities and context of the patient.

While sensible, this path is hindered by the translation of guidelines into quality metrics and pay-for-performance schemes that reduce the possibility of tailoring carefully the application of the evidence to a particular patient. A review of the guidelines published discovers not only that these are disease-specific but also context-blind: they tend to remain agnostic as to other comorbidities, patient values and preferences, and patients’ personal and social circumstances. In addition, guideline panels are often overly confident of the net benefit people will experience if they follow their recommendation. So-called “strong” recommendations denote high confidence in benefit in a manner that is not usually warranted. Strong recommendations, often the result of clear evidence of large benefit and of limited harm and resource use, should be interpreted as ‘just do it” recommendations. Thus, clinicians should be held accountable for following or not these strong recommendations. In doing so, however, clinicians find a patient with multimorbidity, often living a complex life, in which the right thing to do is seldom clear without involving the patient in shared decision making. Such patient involvement may result in actions that are not consistent with guidelines and may suggest poor quality care, when in fact it may reflect the approach of a kind and careful clinician.

Richardson and Doster have offered a simple and helpful framework to understand multimorbidity and how it should clinically affect our confidence in the net benefit of interventions. They propose that interventions could interact with conditions and other interventions and affect the baseline risk of patient important outcomes, the vulnerability of patients to the adverse effects of treatment, and the responsiveness to interventions. The possibility of desirable and undesirable effects multiplies as conditions and treatments interact. This should reduce the confidence clinicians and patients have in deriving net benefit from a particular course of action, and the same should happen to guideline panels. And this may still be true, even when the evidence proves robust across a range of patients with other conditions, a test that has seldom been conducted for common interventions.

Dr. Victor Montori is Professor of Medicine at Mayo Clinic. He is a practicing endocrinologist, researcher and author, and also a recognized expert in evidence-based medicine and shared decision-making. Dr. Montori developed the concept of minimally disruptive medicine and works to advance person-centered care for patients with diabetes and other chronic conditions.

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