Do not resuscitate orders and aging: impact of multimorbidity on the decision-making process

The "Do Not Resuscitate" orders (DNR) are defined as advance medical directives to withhold cardiopulmonary resuscitation during cardiac arrest. Age-related multimorbidity may influence the DNR decision-making process. Our objective was to perform a systematic review and meta-analysis of published data examining the relationship between DNR orders and multimorbidity in older patients.

A systematic Medline and Cochrane literature search limited to human studies published in English and French was conducted on August 2012, with no date limits, using the following Medical Subject Heading terms: "resuscitation orders" OR "do-not-resuscitate" combined with "aged, 80 and over" combined with "comorbidities" OR "chronic diseases".

Of the 65 selected studies, 22 met the selection criteria for inclusion in the qualitative analysis. DNR orders were positively associated with multimorbidity in 21 studies (95%). The meta-analysis included 7 studies with a total of 27,707 participants and 5065 DNR orders. It confirmed that multimorbidity were associated with DNR orders (summary OR = 1.25 [95% CI: 1.19-1.33]). The relationship between DNR orders and multimorbidity differed according to the nature of morbidities; the summary OR for DNR orders was 1.15 (95% CI: 1.07-1.23) for cognitive impairment, OR=2.58 (95% CI: 2.08-3.20) for cancer, OR=1.07 (95% CI: 0.92-1.24) for heart diseases (i.e., coronary heart disease or congestive heart failure), and OR=1.97 (95% CI: 1.61-2.40) for stroke.

This systematic review and meta-analysis showed that DNR orders are positively associated with multimorbidity, and especially with three morbidities, which are cognitive impairment, cancer and stroke.