Social selection in historical time: The case of tuberculosis in South Korea after the East Asian financial crisis

The perspectives of social selection and causation have long been debated. Social selection theory is as “social” as social causation theory, since all diseases are social and no biological process occurs outside society. To identify the social selection pathway and historical juncture affected by socioeconomic and political changes, we investigated the reciprocal impact of suffering from tuberculosis (TB) on the current socioeconomic position (SEP), stratified by childhood SEP. We also examined the extent to which the social consequences of ill health changed since the East Asian economic downturn. Data were collected for 2007–2012 from the Korea National Health and Nutritional Examination Survey. To identify associations between TB history and current household income (HHI), we constructed an ordinal logistic regression model adjusted for covariates, including age, gender, educational attainment, and job status. We adopted a recursive regression model to examine trend changes in this association from 1980–2012 to 2003–2012. Of 28,136 participants, 936 had experienced TB. In the first ordinal logistic regression, the TB group was more likely to have lower HHI than the non-TB group. The odds ratios (ORs) increased from 1.30 (1980–2012) to 1.86 (2003–2012) for the TB group, increasing their probability of having low HHI. Among the low childhood SEP group, the TB group’s probability of having low HHI was 1.35 (95% confidence interval [CI]: 1.16–1.57) during 1980–2012, which increased to 2.01 (95% CI: 1.37–2.95) during 2003–2012. For the high childhood SEP group, the TB group’s OR range fluctuated, similar to that for the non-TB group. The results support the social selection pathway from TB history to adverse impact on current SEP. Our study identified downward social mobility due to TB history among the low childhood SEP group. Moreover, negative social consequences deteriorated since the East Asian economic crisis.