Abstract Background In many people with acutely life-threatening illnesses, the will to undergo treatment is not known with sufficient precision. It is often unclear whether the person concerned would have consented to life-sustaining measures or would have preferred to die with palliative care. This applies in particular to the vulnerable group of elderly, chronically ill/fragile people. It is not uncommon for people to reject the risks/burdens of medical treatment, even if there is a chance of success. On the other hand, there are many people who fight to continue living, even if this can be associated with great burdens and the outcome is rather uncertain. Aim of the study is to determine the characteristics of cardiologic patients who refuse to discuss treatment wishes/preferences in case of acute emergencies, temporary (e.g. in the context of intensive care unit (ICU) treatment), or permanent (vegetative state) inability to consent. Methods Prospective, questionnaire-based cross-sectional study including Hospital Anxiety and Depression Scale (HADS) and assessment of quality of life using the 12-item Short Form Health Survey (SF-12) on normal cardiology wards. Results 455 cardiologic patients were interviewed (mean age 71.2 ± 12.9 years, 39.6% female), 76.1% had moderate-severe concomitant diseases according to the Carlsson Comorbidity Index (4.3 ± 2.4 points) (see Table I). 23.5 % of respondents did not wish to address the above-mentioned question, they were significantly older (74.6 ± 13.1 vs. 69.9 ± 12.8 years; p=0.0009), had more comorbidities, were less likely to have a high level of education (university degree: 13.0 % vs. 30.6 %; p=0.0021) and were less likely to be employed (11.7 % vs. 25.8 %; p=0.0026). Furthermore, these patients live alone more frequently (45.8% vs. 30.6%; p=0.0048) and are less likely to live in a partnership (52.0% vs. 68.0%; p=0.0043). Refusal of an advance directive was also more common (22.5% vs. 10.7%; p=0.05), quality of life was impaired (42.4 ± 9.8 vs. 45.9 ± 10.5 points; p=0.0022), and the HADS-score levels were higher (15.6 ± 7.3 vs. 12.7 ± 7.8 points; p=0.0007). Conclusions A relevant proportion of our patients refuse to discuss treatment wishes/preferences in case of acute emergencies, temporary or permanent inability to consent. Paradoxically, these were patients for whom it would make particular sense (older, sicker, and more socially isolated patients). Those patients are also prone to anxiety and depression, and have a reduced quality of life.