Long-term experience on assisted suicide in Switzerland: dementia, mental disorders, age-related polymorbidity and the slippery slope argument

Abstract

Objectives: According to the Swiss medico-ethical guidelines valid between 2004 and 2018, the key criterion for assisted suicide (AS) was that the patients who wished to die suffered with a disease leading to death in the foreseeable future. Critics of AS fears that broadening of the medical indications will lead to an uncontrolled expansion to persons who are not terminally ill (slippery slope argument). We evaluated to what extent this broadening took place in practice over time.

Study design: Retrospective national cohort study.

Methods: By using data of the Swiss Federal Statistical Office, we analyzed the long-term development of AS in Switzerland over a 20-year period (1999-2018; n = 8738 cases). We classified the cases into one of three categories regarding the aforementioned key criterion for AS.

Results: In 43.6% of AS cases, the criterion 'end of life is near' was met. In 5.3% of cases, this criterion was not met (4.7%: mental disorders; 0.6%: dementia). In 51.1% of cases, the reason underlying AS comprised several, mostly age-related diseases and/or functional impairments; the aforementioned key criterion, however, was probably not met in most of the cases. Over time, the number of cases doubled over each 5-year period; this increase occurred similarly for the three categories.

Conclusion: The fact that many AS cases took place outside the valid medico-ethical guidelines might be interpreted as a development in the idea of the slippery slope argument. The fact that the percentage distribution of these cases remained unchanged over time argues against it.

Keywords: Assisted suicide; Dementia; Medical aid in dying; Mental disorders; Old age suicide.