Low TT4 as a predictor of poor outcomes in severe encephalitis: a multivariate analysis of 94 patients

ABSTRACT

Background: To investigate the prognostic value of acute thyroid function in patients with severe encephalitis.

Methods: We retrospectively analyzed information from patients with severe encephalitis from June 2012 to June 2017. Using multivariate logistic regression analysis, we examined predictors of poor outcomes in these patients after 6 months.

Results: A total of 94 patients with severe encephalitis were included in the study. Univariate analysis showed that patients with good or poor outcomes had significantly different total thyroxine (TT4) (P = 0.012) and free triiodothyronine (FT3) (P = 0.049) levels, mechanical ventilation requirements (P < 0.001), pulmonary infection complications (P = 0.001), lengths of neurological intensive care unit (P = 0.003) and total hospital (P = 0.012) stay, and Acute Physiology and Chronic Health Evaluation (APACHE II) (P = 0.005) and Glasgow Coma Scale (GCS) (P = 0) scores. The results of multivariate analysis suggested the following factors to be associated with a poor outcome: a low TT4 level (OR 0.303, 95% CI 0.100–0.923) and a low GCS score (OR 0.683, 95% CI 0.506–0.923).

Conclusions: Low TT4 has a predictive value for the adverse outcomes of severe encephalitis; further study is needed for verification.

KEYWORDS:

• Encephalitis
• total thyroxine
• neurological intensive care unit
• outcome
• predictor

Acknowledgments

The authors are sincerely grateful for the support of the Department of Neurology, the First Affiliated Hospital of Chongqing Medical University. In addition, we thank all patients for their participation in this study.

Authors’ contributions

Study concept and design: GF, XT, and XW. Acquisition, analysis, or interpretation of data: GF, XT, LW, and LZ. Drafting of the manuscript: GF and XT. Statistical analysis: GF and XT. Study supervision: XW and XT. GF and XT contributed equally and share first authorship.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This study was supported by grants from the National Natural Science Foundation of China (Nos. 81471319, 81671301).