[Economic crises and incidence of suicide in Iceland 1911-2017]

Suicides are number 16 as a cause of death worldwide. Causes are not always known, often associated with depression or trauma. Suicide incidence has decreased world- wide in the past three decades. The economic crisis of 2008 led to an increase in many countries. Many confounding factors make comparisons between countries difficult. This study assesses the possible impact of economic crises in Iceland on suicide incidence.

The work is based on suicide data from 1911 to 2017 and six economic crises from 1918 to 2008. The incidence is calculated five and ten years before and after the index year of each crisis. Possible crisis impact was assessed by applying a quasi-Poisson model to the data. Variance can be greater than model shows, so overdispersion was assessed. The evolution over time is assessed by inspection of cumulative sum of squared -residuals (CUSUMSQ).

Suicide incidence increased from 1930, beginning to decline around 1990. Given a small population size there are wide upwards incidence fluctuations, within and outside the crisis -periods. The crises of 1931 and 1948 showed an increase, wheras in the others there is no change or a decrease. The sizes of deviations from expected value are, for the whole period, in compliance with the quasi-poisson model for counts.

There is no statistical correlation between the six economic crises and suicide incidence in the Icelandic data. The study is based on population incidence and does not preclude a negative impact of economic crises on individuals.