Thyroid hormone profile in preeclampsia patients: a case control study

Figures & data

Table 1. General characteristics of study participants.

Variables	Preeclampsia (N = 52)	Gestational hypertension (GH) (N = 23)	Normotensives (N = 58)
Age (yrs)	33.19 ± 5.61	34.17 ± 5.84	32.08 ± 2.58
Gest. age (wks)	29.15 ± 6.86	31.43 ± 5.41	28.17 ± 6.51
BMI (Kg/m2)	32.62 ± 6.43*	36.42 ± 6.96***	29.58 ± 4.19
Parity n (%)
0	15 (28.8)	3 (13.0)	16 (27.6)
1	13 (25.0)	3 (13.0)	23 (39.7)
2	13 (25.0)	7 (30.4)	13 (22.4)
> 2	11 (21.2)	10 (43.5)	6 (10.3)
Gravidity: n (%)
1	6 (11.5)	1 (4.3)	21 (36.2)
2	13 (25.0)	4 (17.4)	14 (24.1)
3	12 (23.1)	4 (17.4)	6 (10.3)
> 3	21 (40.4)	18 (78.3)	17 (29.3)

BMI = body mass index, Gest. age = gestational age, *Unemployed include students. *Preeclampsia = patients with blood pressure ≥ 140/90 mmHg and with urine protein. Gestational hypertension = pregnant women diagnosed with high blood pressure (pressure ≥ 140/90 mmHg) but no urine protein. Normotensives = Pregnant women with normal blood pressure and undetected urine protein. PE and GH are compared with the normotensives.

Table 2. Clinical characteristics of participants.

Variables	Preeclampsia (PE) (N = 52)	Gestational hypertension (GH) (N = 23)	Normotensives (NT) (N = 58)	p-value
SBP (mmHg)	152.21 ± 10.06***	148.34 ± 14.10***	116.71 ± 11.76	< 0.0001
DBP (mmHg)	97.48 ± 9.13***	95.17 ± 8.44***	72.67 ± 8.31	< 0.0001
Pulse (bpm)	92.46 ± 14.07***	93.17 ± 12.68***	80.01 ± 7.01	< 0.0001
Proteinuria: n (%)
+	45 (86.5)	–	–
++	7 (13.5)	–	–

SBP = systolic blood pressure, DBP = diastolic blood pressure. Result is presented as mean ± standard deviation. PE and GH are compared with the normotensives. +1 = urine protein of about 300 mg/24 h. *p < 0.05, **p < 0.01, ***p < 0.0001.

Table 3. Thyroid hormone profiles of study participants.

Variables	Preeclampsia (N = 30)	Gestational hypertension (N = 23)	Normotensives (N = 30)	p-value
TSH (μIU/ml)	2.58 ± 0.98	2.44 ± 1.18	2.79 ± 0.63	0.630
FT3 (pmpl//l)	4.07 ± 0.75	4.16 ± 0.45	4.21 ± 0.92	0.7676
FT4 (pmpl//l)	12.33 ± 2.26	12.99 ± 1.24*	11.55 ± 1.94	0.0272

N = sample size, TSH = thyroid stimulating hormone, FT3 = free triiodothyronine, FT4 = thyroxine. TSH normal range: 0.53–5.50 μIU/ml, FT3 normal range: 2.8–7.3 pmpl//l, FT4 normal range: 8.5–22.5 pmol/l. Result is presented as mean ± standard deviation. ^Δ Compared with other categories, mean difference is statistically significant. Kruskal–Wallis test was used to compare TSH values. *p < 0.05 was considered statistically significant.

Table 4. Thyroid dysfunction prevalence among study participants.

Thyroid dysfunction classification	Preeclampsia (N = 30)	Gestational hypertension (N = 23)	Normotensives (N = 30)
Sub-clinical hypothyroidism n (%)	1 (3.3)	1 (4.3)	1 (3.3)
Primary hypothyroidism n (%)	0 (0.0)	0 (0.0)	0 (0.0)
Sub-clinical hyperthyroidism n (%)	3 (10.0)	0 (0.0)	1 (3.3)
Primary hyperthyroidism n (%)	0 (0.0)	0 (0.0)	0 (0.0)

N = sample size, TSH normal range: 0.53–5.50 μIU/ml, FT3 normal range: 2.8–7.3 pmpl//l, FT4 normal range: 8.5–22.5 pmol/l. Sub-clinical hypothyroidism: when TSH is higher than 5.60 IU/ml, FT3 and FT4 within normal range. Primary hypothyroidism: when TSH is greater than 5.60 μIU/ml, FT3 and FT4 less than normal. Sub-clinical hyperthyroidism: when TSH is less than 0.53 μIU/ml, FT3 and FT4 within normal range. Primary hyperthyroidism: when TSH is less than 0.53 μIU/ml, FT3 and FT4 higher than normal.