Depressed TSH level as a predictor of poststroke fatigue in patients with acute ischemic stroke

To investigate whether thyroid function profiles can predict poststroke fatigue (PSF) in patients with acute ischemic stroke.

Patients with stroke were consecutively recruited within 3 days of onset in Jinling Hospital. Serum levels of thyroid hormones, thyroid antibodies, hematologic indexes, and biochemical indexes were measured on admission. Fatigue was scored using the Fatigue Severity Scale. Associations were analyzed with multivariate regression and restricted cubic splines.

Of the 704 patients with stroke, 292 (41.5%) were diagnosed with fatigue in the acute stage and 224 (35.3%) 6 months after the index stroke. The serum levels of thyroid-stimulating hormone (TSH) were inversely associated with the risk of PSF in both the acute phase and at follow-up evaluations after adjusting for potential confounders (odds ratio 0.30, 95% confidence interval 0.24-0.37 in the acute phase, and odds ratio 0.70, 95% confidence interval 0.58-0.84 at follow-up). The subgroup analysis indicated that in the acute phase of ischemic stroke, TSH was associated with severity of PSF in the groups with euthyroidism (β = -0.70, p < 0.001), subclinical hypothyroidism (β = -0.44, p < 0.001), and low-T₃ syndrome (β = -0.34, p = 0.008). Higher TSH was associated with better Fatigue Severity Scale scores in patients with low-T₃ syndrome 6 months after the index stroke (β = -0.35, p = 0.01). Furthermore, in the group with low-T₃ syndrome, FT₃ serum level could also indicate a higher risk of PSF (β = -2.54, p < 0.001 in the acute phase, and β = -2.67, p < 0.001 at follow-up).

Thyroid function profiles may predict fatigue after acute ischemic stroke, suggesting that neuroendocrine responses could have a role in PSF.