Disease duration-stratified associations of thyroid hormone levels with psychopathology in hospitalized patients with schizophrenia: A cross-sectional study

Table 5 Correlations between thyroid hormone levels and Positive and Negative Syndrome Scale profile scores in patients with stable schizophrenia

Variable		Total score		General psychopathology
		β (95%CI)	P value	β (95%CI)	P value
Disease duration: 0-10 years	T3	-	-	-5.457 (-13.899 to 2.985)	0.2
	T4	-	-	-0.848 (-1.564 to -0.133)	0.021
	FT3	-	-	-2.483 (-4.693 to -0.273)	0.028
Disease duration: 10.1-20 years	FT4	-0.981 (-2.139 to 0.177)	0.095	-	-
	TSH	-	-	-1.429 (-2.348 to -0.509)	0.003

Linear regression models assessing the association between thyroid hormone level and Positive and Negative Syndrome Scale profile scores. General psychopathology: For the subgroup with disease duration 0-10 years: When triiodothyronine or thyroxine were primary exposures, adjusted for antipsychotic type and coronavirus disease 2019 history; when free triiodothyronine was the primary exposure, adjusted for antipsychotic type, coronavirus disease 2019 history, and age. For the subgroup with disease duration 10.1-20 years: When thyroid stimulating hormone was the primary exposure, adjusted for sex, hospitalization duration, chlorpromazine equivalent dose, Patient Health Questionnaire-9 scores, Generalized Anxiety Disorder 7-item scores, and Montreal Cognitive Assessment-Chinese version scores. CI: Confidence interval; TSH: Thyroid stimulating hormone; T3: Triiodothyronine; FT3: Free triiodothyronine; T4: Thyroxine; FT4: Free thyroxine.