Social vulnerability and surgery outcomes: a cross-sectional analysis

Abstract

Background: Post-operative complications present a challenge to the healthcare system due to the high unpredictability of their incidence. Socioeconomic conditions have been established as social determinants of health. However, their contribution relating to postoperative complications is still unclear as it can be heterogeneous based on community, type of surgical services, and sex and gender. Uncovering these relations can enable improved public health policy to reduce such complications.

Methods: In this study, we conducted a large population cross-sectional analysis of social vulnerability and the odds of various post-surgical complications. We collected electronic health records data from over 50,000 surgeries that happened between 2012 and 2018 at a quaternary health center in St. Louis, Missouri, United States and the corresponding zip code of the patients. We built statistical logistic regression models of postsurgical complications with the social vulnerability index of the tract consisting of the zip codes of the patient as the independent variable along with sex and race interaction.

Results: Our sample from the St. Louis area exhibited high variance in social vulnerability with notable rapid increase in vulnerability from the south west to the north of the Mississippi river indicating high levels of inequality. Our sample had more females than males, and females had slightly higher social vulnerability index. Postoperative complication incidence ranged from 0.75% to 41% with lower incidence rate among females. We found that social vulnerability was associated with abnormal heart rhythm with socioeconomic status and housing status being the main association factors. We also found associations of the interaction of social vulnerability and female sex with an increase in odds of heart attack and surgical wound infection. Those associations disappeared when controlling for general health and comorbidities.

Conclusions: Our results indicate that social vulnerability measures such as socioeconomic status and housing conditions could affect postsurgical outcomes through preoperative health. This suggests that the domains of preventive medicine and public health should place social vulnerability as a priority to achieve better health outcomes of surgical interventions.

Keywords: Housing status; Postsurgical complications; Sex interaction; Social vulnerability; Socioeconomic status.

Fig. 1

Sample outcome mapped with social vulnerability index (SVI): Mapping of SVI in counties of St. Louis bistate area with the odds of a sample outcome (abnormal heart rhythm) stratified by sex-at-birth for each census tract. Background color specifies the SVI value for the census tract and the pie chart radius indicates the proportion of the census tract population with the adverse outcome while the portion of the pie indicates the sex percentages. Counties with less than 20 subjects are omitted

Fig. 2

Coefficients of the overall SVI value in the association models for each outcome: Results of each level are plotted with uncorrected 95% confidence intervals

Fig. 3

Coefficients of the interaction of overall SVI value with sex in the association models for each outcome: Results of each level are plotted with uncorrected 95% confidence intervals

Fig. 4

Coefficients of the theme-based SVI value in the association models for each outcome: Results of level 1 modeling for each theme are plotted with uncorrected 95% confidence intervals

Fig. 5

Coefficients of the interaction of theme-based SVI value with sex in the association models for each outcome: Results of level 1 modeling for each theme are plotted with uncorrected 95% confidence intervals