Suicide mortality in the South African context : exploring the role of social status and environmental circumstances

Abstract

Suicide is a serious public health problem worldwide, but is differentially distributed across social groups and regions. The goal of this thesis, focusing on the post-apartheid transitional setting of South Africa, is to advance knowledge of the relationship between individual social status (race and sex), contextual factors and suicide mortality. The accuracy of the available suicide data is also assessed.

All five studies forming the thesis are based on the National Injury Mortality Surveillance System (NIMSS), currently the only source of epidemiological data on suicide mortality in South Africa. Census figures provide denominator data and area attributes. Inputs from experts and additional victim data are gathered from the medico-legal system.

The first three studies investigate the relative importance of suicide across sociodemographic groups, compared to other injury deaths (Study I), across six cities (Study II), and within one city ¨C Tshwane (Study III). As in other settings, mortality by suicide is unequally distributed across socio-demographic groups, with the order and magnitude of the differences varying across cities. While Blacks have the highest absolute numbers both overall and across most sex-specific groups and cities, males and Whites are typically most affected when rates are calculated. For all races except Whites, suicides are concentrated in the younger age groups.

Study III additionally examines how the cross-sectional clustering of socio-economic and environmental descriptors of Tshwane residential areas impacts on the race- and sexbased suicide outcome. Main dimensions of the living circumstances of residential areas (i.e., socio-economic circumstances, economic need, and matrimony) are found to influence age-adjusted suicide rates for both sexes but minimally so for race groups. Less favourable clusters of circumstances have a protective effect.

Suicide data accuracy is assessed in the last two studies. Decisional processes of those medical practitioners asked to determine the apparent manner of death of each case entered in the NIMSS are assessed in semi-structured interviews (Study IV), and dockets produced from standard medico-legal procedures serve as the gold standard against which to compare NIMSS certifications (Study V). Medical practitioners differed in their opinions both regarding the quality of currently available data for suicide determinations, and in the applicability of the U.S.©\developed criteria in South Africa. Despite this, the accuracy of the suicide determinations was high, at least in the one city (Tshwane) studied.

In sum, suicide mortality in post-apartheid South Africa varies widely across sex and race, with contextual factors seeming to influence these differing outcomes, more so for sex than for race. Although suicides are outnumbered by other injury deaths overall, this is not the case for several sex-, race- and age-specific groups, and rates indicate that suicide is a substantial public health burden that should no longer be given low priority in the health system. Medical practitioner expertise appears to provide accurate input for the determination of suicide deaths.