The Association Between Hypothyroidism Treatment and Mortality in Patients Hospitalized in Surgical Wards

Figures & data

Table 1. Baseline characteristics and comorbidities of patients according to TSH levels before admission.

	TSH ≤0.5 (n = 120)	0.5< TSH < 5.0 (n = 988)	5.0≤ TSH ≤ 10.0 (n = 233)	TSH >10 (n = 110)
Patient Characteristics
Age (years), mean	64.1 ± 16.4*	66.7 ± 16.1	68.4 ± 17.1	71.7 ± 15.1*
Age above 60 years, n (%)	80 (66.7%)	718 (72.7%)	166 (71.2%)	86 (78.2%)
Women, n (%)	96 (80.0%)	770 (77.9%)	162 (69.5%)*	73 (66.4%)*
Smoking (%)	8 (6.7%)	75 (7.6%)	11 (4.7%)	12 (10.9%)
Alcohol (%)	0 (0%)	3 (0.3%)	2 (0.9%)	1 (0.9%)
BMI, mean	27.8 ± 6.3	29.0 ± 6.9	28.7 ± 7.3	27.4 ± 6.0
TSH (mIU/L), mean	0.20 ± 0.16*	2.53 ± 1.18	6.86 ± 1.44*	24.18 ± 19.59*
Comorbidities, n (%)
Malignancy	31 (25.8%)	229 (23.2%)	40 (17.2%)*	20 (18.2%)
Hypertension	36 (30.0%)	352 (35.6%)	81 (34.8%)	55 (50.0%)*
Diabetes Mellitus	74 (61.7%)	572 (57.9%)	144 (61.8%)	74 (62.3%)
Ischemic Heart Disease	7 (5.8%)	86 (8.7%)	34 (14.6%)*	19 (17.3%)*
Congestive Heart Failure	3 (2.5%)	48 (4.9%)	17 (7.3%)	13 (11.8%)*
Cerebrovascular Disease	3 (2.5%)	34 (3.4%)	9 (3.9%)	4 (3.6%)
Chronic Renal Failure	4 (3.3%)	22 (2.2%)	7 (3.0%)	10 (9.1%)*
Cause of hospital admission, n (%)
Gastrointestinal Tract Disorders	33 (27.5%)	260 (26.3%)	68 (29.2%)	35 (31.8%)
Hepatobiliary and Gallbladder Disorders	21 (17.5%)*	114 (11.5%)	30 (12.9%)	14 (12.7%)
Surgical Oncology	31 (25.8%)	229 (23.2%)	40 (17.2%)	20 (18.2%)
Bariatric Surgery	6 (5.0%)	77 (7.8%)	17 (7.3%)	3 (2.7%)
Other (abdominal pain investigations, non-obstructive hernias, infections)	29 (24.2%)*	308 (31.2%)	78 (33.5%)	38 (34.5%)
Surgical procedure performed during hospitalization, n (%)
Underwent Elective Surgery	68 (53.3%)	520 (52.6%)	88 (37.8%)*	34 (30.9%)*
Underwent Urgent Surgery	9 (7.5%)	88 (8.9%)	26 (11.2%)	8 (7.3%)

*p < 0.05 compared with normal TSH levels (>0.5 and < 5.0 mIU/L).

Figure 1. Patient flow diagram.

Table 2. Length of hospital stay, 30-day and end-of-follow-up mortality according to TSH levels before admission.

		TSH ≤0.5	0.5< TSH < 5.0	5.0≤ TSH ≤ 10.0	TSH >10.0
N		120	988	233	110
Length of stay in days, mean ± SD (median)		5.9 ± 6.9 (3.0)	4.9 ± 4.6 (3.0)	5.7 ± 7.0 (4.0)	6.2 ± 5.7 (5.0)
30-Day Mortality	Total	6 (5.0%)	24 (2.4%)	14 (6.0%)	11 (10.0%)
	Low Free T4	0/2 (0.0%)	1/15 (6.7%)	2/9 (22.2%)	5/25 (20.0%)
	Normal Free T4	5/92 (5.4%)	9/434 (2.1%)	10/215 (4.7%)	6/83 (7.2%)
	High Free T4	1/24 (4.2%)	1/25 (4.0%)	2/6 (33.3%)	0/2 (0.0%)
30-Day Mortality (Odds ratio)	Unadjusted OR	2.1 (0.8–5.3)	Ref	2.6 (1.3–5.0)*	4.5 (2.1–9.4)*
	Adjusted OR^↑	5.8 (1.9–17.9)*	Ref	2.3 (1.1–5.1)*	3.4 (1.3–8.7)*
End of Follow-up Mortality	Total	34 (28.3%)	253 (25.6%)	85 (36.5%)	54 (49.1%)
	Low Free T4	0/2 (0.0%)	6/15 (40.0%)	6/9 (66.7%)	13/25 (52.0%)
	Normal Free T4	25/92 (27.2%)	113/434 (26.0%)	73/215 (34.0%)	41/83 (49.4%)
	High Free T4	9/24 (37.5%)	11/25 (44.0%)	4/6 (66.7%)	0/2 (0.0%)
End of Follow-up Mortality (Hazard ratio)	Unadjusted HR	1.1 (0.8–1.6)	Ref	1.5 (1.2–2.0)*	2.2 (1.6–3.0)*
	Adjusted HR^↑	1.3 (0.9–2.0)	Ref	1.2 (1.0–1.6)*	1.7 (1.2–2.4)*

*p < 0.05 compared with normal TSH levels (>0.5 and < 5.0 mIU/L).

↑ adjusted for age on admission, gender, smoking status, body mass index, malignancy, hypertension, diabetes, ischemic heart disease, congestive heart failure, cerebrovascular accident, chronic renal failure, cause of hospital admission, and surgical procedure performed during hospitalization.

Table 3. 30-day and end-of-follow-up mortality according to TSH levels before admission, divided into two age groups: <60 years and ≥60 years.

Age			TSH ≤0.5	0.5< TSH < 5.0	5.0≤ TSH ≤ 10.0	TSH >10.0
<60 years	N		40	270	66	25
	30-Day Mortality	Total	1 (2.5%)	1 (0.4%)	1 (1.5%)	0 (0.0%)
	30-Day Mortality (Odds ratio)	Unadjusted OR	6.8 (0.7–68.3)	Ref	4.0 (0.4–40.0)	0.6 (0.0–6.0)
		Adjusted OR^↑	3.7 (0.4–37.2)	Ref	2.4 (0.4–15.2)	2.0 (0.0–34.1)
	End of Follow-up Mortality	Total	4 (10.0%)	13 (4.8%)	6 (9.1%)	4 (16.0%)
	End of Follow-up Mortality (Hazard ratio)	Unadjusted HR	2.6 (0.9–8.1)	Ref	2.1 (0.8–5.6)	4.0 (1.3–12.2)*
		Adjusted HR^↑	1.7 (0.4–7.5)	Ref	1.3 (0.4–4.1)	2.7 (0.7–10.7)
≥60 years	N		80	718	167	85
	30-Day Mortality	Total	5 (6.3%)	23 (3.2%)	13 (7.8%)	11 (12.9%)
	30-Day Mortality (Odds ratio)	Unadjusted OR	2.1 (0.8–5.6)	Ref	2.6 (1.3–5.2)*	4.5 (2.1–9.5)*
		Adjusted OR^↑	4.2 (1.4–12.1)*	Ref	2.5 (1.1–5.5)*	3.7 (1.5–9.1)*
	End of Follow-up Mortality	Total	30 (37.5%)	240 (33.4%)	79 (47.3%)	50 (58.8%)
	End of Follow-up Mortality (Hazard ratio)	Unadjusted HR	1.1 (0.7–1.6)	Ref	1.6 (1.2–2.1)*	2.1 (1.5–2.8)*
		Adjusted HR^↑	1.2 (0.8–1.8)	Ref	1.3 (1.0–1.8)*	1.7 (1.2–2.5)*

*p < 0.05 compared with normal TSH levels (>0.5 and < 5.0 mIU/L).

↑ adjusted for age on admission, gender, smoking status, body mass index, malignancy, hypertension, diabetes, ischemic heart disease, congestive heart failure, cerebrovascular accident, chronic renal failure, cause of hospital admission, and surgical procedure performed during hospitalization.

Figure 2. Kaplan–Meier analysis of long-term mortality according to pre-admission TSH levels. Comparison between TSH levels of ≤ 0.5, TSH levels between 0.5 and 5.0, TSH levels between 5.0 and 10.0, and TSH levels > 10.0mIU/L.

Figure 3. Adjustedend of follow-up mortality hazard ratio according to pre-admissionTSH levels.

Data availability statement

The data that support the findings of this study are available from the corresponding author, AA, upon reasonable request.