Journal of Thyroid Research

Clinical Study

A Risk Prediction Index for Amiodarone-Induced Thyrotoxicosis in Adults with Congenital Heart Disease

Table 1

Overall cohort and group characteristics ( 𝑛 = 1 6 9 ).
VariableEntire cohort ( 𝑛 = 1 6 9 )Group with AITGroup without AIT 𝑃 value
Men— 𝑛 (%)89 (52.7)13 (56.5)76 (52.1)0.69
Age (years)—mean (SD)42.7 (14.1)35.3 (12.2)43.8 (14.1)0.006
BMI (kg/m2)—mean (SD)25.2 (4.9)22.0 (3.1)25.8 (4.9)<0.001
Weight (kg)—mean (SD)69.9 (16.5)62.2 (11.8)75.5 (16.5)0.001
Supraventricular arrhythmia*—n (%)152 (90)23 (100)129 (88.4)0.084
Baseline systolic blood pressure (mm Hg)—mean (SD)117 (13)116 (17.5)117.2 (12.5)0.77
Cyanotic CHD diagnosis— 𝑛 (%)34 (20.1)8/23 (34.8)26/146 (17.8)0.059
Tricuspid regurgitation— 𝑛 (%)
 Absent
 Mild
 Moderate
 Severe		37 (25)
50 (35)
23 (16)
34 (24)		7 (37)
7 (37)
2 (10.5)
3 (15.8)		30 (24)
43 (34)
21 (16.8)
31 (24.8)		 0.17**
Left ventricular ejection fraction % —mean (SD)47.5 (13.5)43 (13.2)48 (13.4)0.15
Hematocrit (%)—mean (SD)42.9 (7.2)43.5 (4.7)42.8 (7.5)0.61
Protein-losing enteropathy— 𝑛 (%)8 (4.8)0 (0)8 (5.5)0.6
Goiter— 𝑛 (%)19 (12.9)7 (35)12 (9.5)0.002
Albumin (g/dL)—median (IQR)4.3 (4.0–4.5)4.4 (4.2–4.7)4.3
(4–4.5)		0.13
Average amiodarone dose/day (mg/day)—median (IQR)200 (200–300)200 (200–250)200 (200–300)0.77
Average amiodarone dose/kg/day (mg/kg/day)—median (IQR)3.04 (2.42–3.87)3.51 (2.32–3.85)2.96 (3.05–4.12)0.015
Time on amiodarone (days)—median (IQR)1147 (546–2438)1066 (849–1470)1206 (393–2529)0.79
Cumulative amiodarone exposure (g/kg)—median (IQR)3.7 (1.2–7.3)3.5 (2.7–5.2)3.8 (1.1–7.3)0.60
Abnormal liver tests— 𝑛 (%)26 (16.5)2 (8.7)24 (17.8)0.27
Abnormal pulmonary function test— 𝑛 (%)67 (84.4)***14 (100)53 (81.5)0.11
Hospital admissions per year on amiodarone****—median (IQR)0.4 (0.2–1.1)0.4 (0.1–1.0)0.6 (0.2–1.1)0.57
Days in the hospital per year on amiodarone****—median (IQR)3.4 (1.2–8.0)2.6 (0.9–6.4)4.5 (1.7–13.5)0.15
* The ventricular arrhythmias treated were ventricular tachycardia, premature ventricular contractions, and ventricular fibrillation.
** 𝑃 value for trend.
*** This variable was available in less than 75% of the entire cohort.
**** 23 age and gender matched pairs used for this analysis.
BMI: body mass index; CHD: congenital heart disease.