Preoperative thyroid hormone replacement associated with higher risk of complications in major abdominal surgery

The study found a 1.5-fold increased risk of severe morbidity and a 1.7-fold greater risk of serious sepsis among individuals on preoperative thyroid replacement before major abdominal surgery. Additionally, patients with pre-existing hypothyroidism on thyroid replacement therapy were more likely to undergo open surgery and also correlated with longer hospital stays rather than minimally invasive procedures.

Patients with pre-existing hypothyroidism are shown to have significantly increased length of stay and increased morbidity. There are opportunities for perioperative optimization and risk stratification based on thyroid replacement.

Considering that the relationship between hypothyroidism and complications following major abdominal surgery has not been elucidated, Matthew E. Spector, University of Pittsburgh, Pittsburgh, PA, USA, and colleagues aimed to determine the association between preoperative thyroid hormone replacement and complications after major abdominal surgery.

For this purpose, the researchers performed a retrospective case series of enrollees of the Michigan Surgical Quality Collaborative (MSQC) who underwent major abdominal surgery at an academic institution over 10 years. The principal explanatory variable was preoperative thyroid hormone replacement. The primary outcomes included mortality, morbidity, and length of stay. A total of 2700 patients were identified.

The researchers reported the following findings:

• On multivariate analysis correcting for established predictors of operative morbidity, patients on preoperative thyroid replacement had a 1.5-fold increased risk of serious morbidity and a 1.7-fold greater risk for serious sepsis.
• Thyroid replacement was associated with a longer length of stay.
• There was a high degree of missing data for the surgical approach (31.1 % missing data). Still, the results suggest that patients on thyroid hormone replacement were more likely to undergo an open rather than minimally invasive surgery.
• Open surgery was associated with a greater risk of serious morbidity and a longer length of stay.

"Preoperative thyroid hormone replacement independently predicts length of stay and operative morbidity following major abdominal surgery," the researchers concluded.

Reference:

The study titled, "Association of preoperative thyroid hormone replacement with perioperative complications after major abdominal surgery," was published in The American Journal of Surgery.

DOI: https://doi.org/10.1016/j.amjsurg.2024.01.018