Mortalité par suicide au Canada depuis le début du XXe siècle : perspectives sociodémographiques et macroéconomiques

For two centuries, the most remarkable transformations in suicide mortality concerns its relationship with age. In particular, Durkheim (1951 [1897]) noted, based on early XIXth century that data, suicide rates increased according to age  reaching its highest point in the elderly. The relationship remained stable for over a century but major disruption occurred worldwide during the last quarter century: substantial increase of suicide rates and particularly those in the youth.  Our study focuses on monitoring suicide mortality temporal age trends in Canada. We use a multidisciplinary approach combining demography, sociology and economics. The period of analysis is the most extensive to date in the country, from the beginning of the vital statistics in the XXth to the XXIst century (1926-2008). National suicide rates are representative for Canadian society changes and further analyses provide characteristics of the phenomenon in the province of Quebec, compared to the rest of Canada. Advanced statistical methods recently developed and econometric techniques are used to estimate the independent age-period-cohort effects and assist taking into account indicators timing. The results of our analysis are presented in the form of scientific articles based on data from Statistics Canada and Institut national de santé publique du Québec.  Findings provided by the Intrinsic Estimator for the first paper suggest a significant effect for all three APC dimensions on suicide mortality in Canada. The following is shown: a) A significant age effect on suicide rate for men up to 24 years old, with a later stabilization, b) Women trend shaped as an inverted "U" and c) both sexes with an inflection point at mid-adulthood. The net period effect for suicide mortality differs in Quebec, extended by 25 years compared to the rest of Canada. A net cohort effect was identified for men baby boomers and X generation in Canada, which was much stronger in Quebec while a recent cohort effect is detected for women born in 1981 to more recent cohorts.  The second paper investigates demographic concurrent paradigms of Easterlin and Preston on cohort size effect. Using a Hierarchical Age-Period-Cohort Cross-Classified Random Effect Model (HAPC-CCREM). We find a significant positive effect in Canada associated with Easterlin (Easterlin) theory: large cohorts have greater suicide rate than small cohorts. More specifically, the effect appears in particular in men and statistically it is significantly stronger in the province of Quebec compared to the rest of Canada.  The last paper focuses on the impact of economic conditions on suicide and brings additional insight on age. Among the three classical theories that attempted to explain the relationship, our results of the AutoRegressive Integrated Moving Average (ARIMA) models are more representative of Durkheim paradigm. Indeed, a significant nonlinear effect is detected with the increase of suicide rates during both periods of economic contraction and expansion. The effect seems specific to men. Still, our results suggest public health responses during periods of economic contraction and expansion. Finally, economic fluctuations appear mostly to affect men and women at mid-adulthood.

Keyphrases: Suicide, Canada, Québec, Durkheim, Age-Période-Cohorte (APC), Intrinsic Estimator (IE), Hierarchical Age-Period-Cohort Cross-Classified Random Effect Model (HAPC-CCREM), AutoRegressive Integrated Moving Average (ARIMA), Quebec, Demography, Sociology, Economy, Age-Periode-Cohort (APC)