# Racial disparities in ankylosing spondylitis risk following tonsillectomy: a large-scale retrospective analysis

## TL;DR

A large study found that White individuals who had a tonsillectomy had a higher risk of developing ankylosing spondylitis compared to other racial groups.

## Contribution

The study reveals racial disparities in ankylosing spondylitis risk following tonsillectomy, highlighting White ancestry as a significant effect modifier.

## Key findings

- Tonsillectomy did not significantly increase overall ankylosing spondylitis risk.
- White individuals who had a tonsillectomy showed a significantly elevated risk of ankylosing spondylitis.
- Racial disparities were observed in the relationship between tonsillectomy and ankylosing spondylitis development.

## Abstract

The objective was to investigate the association between tonsillectomy and subsequent ankylosing spondylitis (AS) risk, with particular emphasis on racial disparities in disease susceptibility.

A retrospective cohort study was conducted using de-identified electronic health records from approximately 120 million patients in the collaboration network in the United States. Patients diagnosed with tonsillar and adenoidal diseases between 2005 and 2023 were selected and divided into surgical and non-surgical cohorts. Propensity score matching (PSM) was employed to balance baseline differences and control for confounding factors, and statistical analyses were performed using Kaplan-Meier survival analysis and Cox proportional hazards models.

After PSM, 173,483 individuals were included in each cohort with well-balanced baseline characteristics. Overall, tonsillectomy did not significantly increase AS risk (HR = 1.26, 95% CI: 0.90-1.75, p = 0.210). Age- and sex-stratified analyses yielded consistent results. However, race-stratified analysis revealed that White individuals who underwent tonsillectomy had significantly elevated AS risk (HR = 1.80, 95% CI: 1.19-2.72, p = 0.005) and higher cumulative incidence compared to matched controls, a finding not observed in other racial groups.

This large-scale study identifies being of White ancestry as a significant effect modifier in the relationship between tonsillectomy and AS development. These findings warrant closer post-operative surveillance for AS symptoms in White patients undergoing tonsillectomy and further mechanistic research.

Infographic summarizing a large-scale retrospective study on racial disparities in ankylosing spondylitis risk following tonsillectomy, indicating that white individuals had a higher hazard ratio of 1.80 compared to the overall population hazard ratio of 1.26; the study included 120 million patients, a final population of 346,966, two propensity-matched groups of 173,483, and spanned eighteen years; study design involved tonsillar or adenoidal disease, surgical versus non-surgical comparison, and follow-up for ankylosing spondylitis.