Multi-drug therapy in chronic condition multimorbidity: a systematic review

Older populations often suffer from multimorbidity and guidelines for each condition are often associated with recommended drug therapy management. Yet, how different and specific multimorbidity is associated with number and type of multi-drug therapies in general populations is unknown.

The aim of this systematic review was to synthesize the current evidence on patterns of multi-drug prescribing in family practice.

A systematic review on six common chronic conditions: diabetes mellitus, cardiovascular disease, cerebrovascular disease, chronic obstructive pulmonary disease (COPD), osteoarthritis and depression was conducted, with a focus on studies which looked at any potential combination of two or more multimorbidity. Studies were identified from searches of MEDLINE, EMBASE, PsychINFO, the Allied and Complementary Medicine Database (AMED) and the Health Management Information Consortium (HMIC) databases from 1960 to 2013.

A total of eleven articles were selected based on study criteria. Our review identified very few specific studies which had explicitly investigated the association between multimorbidity and multi-drug therapy. Relevant chronic conditions literature showed nine observational studies and two reviews of comorbid depression drug treatment. Most (seven) of the articles had focused on the chronic condition and comorbid depression and whether antidepressant management had been optimal or not, while four studies focused on other multimorbidities mainly heart failure, COPD and diabetes.

Very few studies have investigated associations between specific multimorbidity and multi-drug therapy, and most currently focus on chronic disease comorbid depression outcomes. Further research needs to identify this area as key priority for older populations who are prescribed high levels of multiple drug therapy.