Overestimation of Survival Rates of Cardiopulmonary Resuscitation Is Associated with Higher Preferences to Be Resuscitated: Evidence from a National Survey of Older Adults in Switzerland

Background. Many widely used advance directives templates include direct questions on individuals' preferences for cardiopulmonary resuscitation (CPR) in case of decision-making incapacity during medical emergencies. However, as knowledge of the survival rates of CPR is often limited, individuals' advance decisions on CPR may be poorly aligned with their preferences if false beliefs about the survival rates of CPR shape stated preferences for CPR. Methods. We analyzed nationally representative data from 1,469 adults aged 58+ y who responded to wave 8 (2019/2020) of the Swiss version of the Survey on Health, Ageing, and Retirement in Europe (SHARE) to assess the partial association between knowledge of CPR survival rates and stated preferences for CPR using multivariable probit regression models that adjust for social, health, and regional characteristics. Knowledge of CPR survival rates was assessed by asking how likely it is in general in Switzerland for a 70-y-old to survive until hospital discharge from a CPR performed outside of a hospital. Preferences for CPR were measured by asking respondents if they would wish to be resuscitated in case of cardiac arrest. Results. Only 9.3% of respondents correctly assessed the chances for a 70y-old to survive until hospital discharge from a CPR performed outside of a hospital, while 65.2% indicated a preference to be resuscitated in case of a cardiac arrest. Respondents who correctly assessed CPR survival were significantly more likely to wish not to be resuscitated (average marginal effect: 0.18, P \ 0.001). Conclusions. Reducing misconceptions concerning the survival rates of CPR could change older adults' preferences for CPR and make them more likely to forgo such treatments.