Outcomes of acute ischemic stroke in patients with hypothyroidism: A population-based cross-sectional study of 388,000 patients.

Background and ObjectivesHypothyroidism affects 4.6% of the US population, with incidence increasing in recent years. Systemic effects of hypothyroidism include increased serum cholesterol, endothelial dysfunction, and hypertension, which are widely recognized risk factors for stroke. To better understand the prognostic value of thyroid hormone levels in acute ischemic stroke (AIS), this population-based, cross-sectional study aims to examine the clinical outcomes of patients with AIS with hypothyroidism.MethodsThe National (Nationwide) Inpatient Sample was queried from 2016 to 2020 for patients with AIS with a diagnosis of hypothyroidism using International Classification of Disease Ninth and Tenth Revision diagnostic codes. patients with AIS with and without hypothyroidism were assessed for baseline clinical characteristics, interventions, complications, and clinical outcomes. Propensity score matched analysis (1:1) was conducted to control for possible confounding variables.ResultsOf 2,946,195 patients with AIS identified, 388,235 (13.2%) had a concurrent diagnosis of hypothyroidism. After propensity-score matching, hypothyroidism patients were more likely to experience discharge home (odds ratio (OR) = 0.70;  < 0.01), shorter length of stay (LOS) (4.93 vs. 5.19 days;  < 0.01), and lower rates of inpatient death (OR = 0.80; 95% CI: 0.76-0.84;  < 0.01), compared to patients without hypothyroidism.ConclusionsThis retrospective analysis found that patients with hypothyroidism had shorter inpatient LOS, improved discharge disposition, and lower rates of mortality, suggesting that low thyroid hormone levels may be protective in outcomes of AIS. With the rising prevalence of hypothyroidism in the US population, it is increasingly important to investigate its potential effects on patients with cerebrovascular disease.