Effects of Supraphysiological Doses of Levothyroxine on Sleep in Healthy Subjects: A Prospective Polysomnography Study

Table 4

Sleep parameters at baseline and during maximal dosage of levothyroxine (L-T4)¹.

Sleep parameters	Baseline		During T4 treatment		Δ^2		𝑃
	Median	Quartile range	Median	Quartile range	Median	Quartile range
TIB (min)	415	404–477	411	405–471	1	−79–43	.6772
SPT (min)	405	378– 472	401	382–440	−4	−72–39	.6848
TST (min)	384	357–399	378	341–386	−38	−61–29	.2439
SEI	89.5	86.0–95.9	90.4	86.0–92.8	−3.2	−9.3–7.2	.6484
CSS	150	141–185	157	144–180	−2	−14–17	.9324
BM	10.3	9.3–16.1	14.0	12.3–17.0	2.0	−0.4–4.5	.1272
EM	36.5	27.3–39.6	36.9	30.7–48.1	7.8	0.7–9.1	.0681
L S1	6.5	3.5–13.0	9.0	7.5–16.0	1.0	−4.0–7.0	.5295
L S2	10.5	5.0–22.5	11.0	9.0–21.5	0.0	−6.0–9.0	.6084
L S3	16.0	11.5–29.5	18.0	16.5–22.5	5.0	−5.5–10.5	.7354
L S4	23.5	14.0–39.5	23.5	19.0–28.5	4.5	−18.5–9.9	.9233
L REM	72.0	63.0–100.0	71.5	67.5–91.0	5.0	−9.0–20.5	.5417
W (%)	7.1	2.5–11.9	4.5	3.3–8.9	1.3	−8.4–6.4	.8394
S1 (%)	7.6	4.9–9.1	6.8	5.5–9.9	0.6	−2.8–1.2	1.0000
S2 (%)	48.4	40.0–51.6	48.5	37.9–51.8	−1.3	−5.8–1.9	.4548
SWS (%)	15.7	11.1–18.9	13.2	10.8–14.8	0.0	−6.2–4.3	.8394
REM (%)	20.1	16.4–22.7	21.5	17.2–23.9	0.0	−2.4–4.6	.7334
MT (%)	1.3	0.9–1.6	1.5	0.9–2.3	0.2	−0.2–1.1	.2104

1For abbreviations see text.
²Δ refers to intraindividual differences.