How does legalization of physician assisted suicide affect rates of suicide?

Objectives. Several US states have legalized or decriminalised physician assisted suicide (PAS) whilst others are currently considering permitting PAS. Although it has been suggested that legalization could plausibly lead to a reduction in other suicides and to a delay in those other suicides which do occur, to date no research has tested whether these effects can be identified in practice. The aim of this paper was to fill this gap by examining the association between the legalization of physician assisted suicide (PAS) and state-level suicide rates in the USA between 1990 and 2013. Methods. We used regression analysis to test the change in rates of non-physician-assisted suicides (non-PAS) and total suicides (non-PAS plus PAS) before and after legalization of PAS. Results. Controlling for various socio-economic factors, unobservable state- and year effects, and state-specific linear trends, legalizing PAS was associated with a 6.3% (95% confidence interval [CI] = 2.70%, 9.9%) increase in suicides. This effect was larger in the over 65s (14.5%, CI = 6.4%, 22.7%). Introduction of PAS was not associated with a reduction in non-PAS rates, nor with an increase in the mean age of non-PAS. Conclusion. Legalizing PAS has been associated with an increased rate of suicide relative to other states and no decrease in non-PAS. This suggests either that PAS does not inhibit (nor acts as an alternative to) non-PAS, or that it acts in this way in some individuals but is associated with an increased inclination to suicide in other individuals.