Table 1 Baseline, surgical and postoperative characteristics. Univariate analysis of symptomatic PH

Preoperative

 Age in years, median (IQR)

55 (42—68)

59 (44—69)

49 (36—63)

0.001

 Gender: n (%)

0.068

  Female

230 (74.9)

150 (71.8)

80 (81,6)

  Male

77 (25.1)

59 (28.2)

18 (18,4)

 BMI in kg/m², median (IQR)

26.8(23.4 – 30.5)

27.3(24.3 – 30.8)

25.4(22.6 – 29.5)

0.084

 Indication: n (%)

0.181

  Toxic goiter

85 (27.7)

66 (31.6)

19 (19.4)

  Grave’s disease

67 (21.8)

45 (21.5)

21 (23.5)

  Suspicious nodule

72 (23.5)

47 (22.5)

25 (25.5)

  Benign goiter

66 (21.5)

42 (20.1)

24 (24.5)

  Cancer

17 (5.5)

9 (4.3)

8 (8.2)

 Preoperative albumin adjusted calcium in mmol/L, median (IQR)

2.3 (2.3 -2.4)

2.3 (2.2 – 2.4)

2.3 (2.3 – 2.4)

0.703

 Preoperative vitamin D level: n (%)

0.934

  Normal

69 (35.6)

46 (34.8)

23 (37.1)

  Insufficient

107 (55.2)

74 (56.1)

33 (53.2)

  Deficient

18 (9.3)

12 (9.1)

6 (9.7)

  Missing data n = 113

Intraoperative

 Procedure: n (%)

0.999

  Total thyroidectomy

281 (91.5)

191 (91.4)

90 (91.8)

  Completion

26 (8.5)

18 (8.6)

8 (8.2)

 Neck dissection: n (%)

0.01

  Lateral

6 (2)

4 (1.9)

2 (2.0)

  Central unilateral

18 (5.9)

14 (6.7)

4 (4.1)

  Central bilateral

12 (3.9)

2 (1)

10 (10.2)

 Duration of surgery in minutes, median (IQR)

134(114—158)

133(114—158)

134(113—158)

0.928

 Identified parathyroid: n (%)

0.705

  3

114 (37.1)

76 (36.4)

38 (38.8)

  4

193 (62.9)

133 (63.6)

60 (61.2)

 Inadvertent parathyroidectomy: n (%)

0.001

  0

267 (87.0)

192 (91.9)

75 (76.5)

  1

29 (9.4)

11 (5.3)

18 (18.4)

  2

11 (3.6)

6 (2.9)

5 (5.1)

Postoperative

 POD1 albumin adjusted calcium in mmol/L, median (IQR)

2.3 (2.2 – 2.4)

2.3 (2.2 – 2.4)

2.2 (2.1 – 2.3)

 < .001

 POD1 PTH in pg/mL, median (IQR)

36 (15 – 63)

48 (29—68)

9 (1—31)

 < .001

 Hospital stays in days, mean (SD)

1.5 (±1.1)

1.5 (±1.1)

1.5 (±1.1)

0.587

Complications

 RLN palsy: n (%)

0.623

  No

299 (97.4)

203 (97.1)

96 (98.0)

  One sided

6 (2.0)

4 (1.9)

2 (2.0)

  Two sided

2 (0.7)

2 (1.0)

0 (0)

 Cervical hematoma: n (%)

3 (0.9)

2 (0.9)

1 (1.0)

0.272

 Surgical site infection: n (%)

6 (2.0)

2 (1.0)

4 (4.1)

0.085