Psychiatric history modifies the gender ratio of suicide: an East and West comparison

Objective Gender ratios of suicide rates differ greatly across countries. Victoria has a high male: female ratio in suicide that is typical in English-speaking and European countries, while in Hong Kong the low ratio is similar to other SouthEast Asian countries. This study investigates the effect of gender in the psychiatric and non-psychiatric populations to examine how psychiatric history may modulate the effect of gender in these two different communities. Method Review of coronial documentation of all suicide cases in 2000 in Hong Kong and Victoria, Australia. Log-linear model was used to test the gender-psychiatric history-location interaction. Results Gender difference in suicide was narrower in victims with psychiatric history than those without in both communities, albeit gender remained to have an effect even among those with a psychiatric history in Victoria. The impact of cultural-and gender-specific factors is most apparent in suicide cases with no prior psychiatric history in Victoria: the male: female ratio was as high as 8: 1 in this group of victims. Log-linear model results show that the gender-psychiatric history-location interaction was statistically significant. Conclusions The gender differentials in suicide rates in these two communities are mainly driven by gender's effect in the population with no psychiatric history. Severe clinical conditions can override some, but not all, of gender's effects in Victoria. Suicide prevention effort should target gender-specific factors to prevent suicides in men without history of psychiatric disorders.