Is cord blood hepcidin influenced by the low-grade acute-phase response occurring during delivery? A small-scale longitudinal study

Figures & data

Table 1. Longitudinal data (n = 15)^a.

	Trimester 3 (T3)	Cord blood (CB)	Ratio CB/T3^b	p Value for difference^c
GA Week	35 (35–35)	40 (39–41)	—	—
S-hepcidin ng/mL	7.8 (3.6–11.9)	30.5 (21.7–38.8)	4.8 (2.9–10.2)	<.001
S-ferritin µg/L	14 (8–20)	190 (135–310)	15.7 (7.2–28.8)	<.001
sTfR mg/L	4.0 (2.7–4.5)	4.7 (4.3–5.6)	1.4 (1.1–2.0)	<.001
Transferrin g/L	4.0 (3.4–4.4)	1.8 (1.7–2.0)	0.5 (0.4–0.6)	<.001
IL-6 pg/mL	0.9 (0.4–1.0)	2.2 (1.3–5.9)	3.3 (1.7–14.1)	<.001

GA: gestational age; IL-6: interleukin-6; sTfR: soluble transferrin receptor.

^a Values represent median and interquartile range (IQR) (the range between the upper and lower quartiles, i.e. the 25th to the 75th percentile) within brackets.

^b Median ratio is calculated from the individual ratios.

^c Statistically significantly different. Since the majority of variables were significantly skewed, data were log-transformed before statistical analysis. Differences were tested for statistical significance with Student’s paired t-test.

Figure 1. Changes over time. The different panels illustrate longitudinal time course changes in (A) interleukin-6 (IL-6), (B) S-hepcidin, (C) transferrin, (D) S-ferritin, and (E) soluble transferrin receptor (sTfR) throughout pregnancy. Bars show median values and whiskers show the 95% confidence interval (CI). The dotted horizontal lines in panel D indicate the cutoff for exhausted iron stores based on S-ferritin (12 µg/L) and the dotted horizontal lines in panel E indicate the lower concentration of the transferrin receptor (TfR) reference interval (4.4 mg/L). sTfR: soluble transferrin receptor; IL-6: interleukin-6; CB: cord blood; T3: trimester 3.

Figure 2. Correlations during trimester 3 of pregnancy. The different panels illustrate the correlation coefficients for (A) log soluble transferrin receptor (sTfR) versus log S-ferritin; (B) log transferrin versus log S-ferritin; (C) log IL-6 versus log S-hepcidin; (D) log sTfR versus log S-hepcidin; and (E) log S-ferritin versus log S-hepcidin.

Table 2. Correlations in biomarkers sampled in trimester 3 and in cord blood. Pearson correlations with p values.

	Trimester 3 (T3)
	Log S-Hepcidin	0.691 p = .004	−0.825 p = .001	0.539 p = .038	−0.306 p = .268
	0.308 p = .264	Log S-Ferritin	−0.729 p = .002	0.334 p = .223	−0.549 p = .034
Cord blood (CB)	−0.161 p = .566	−0.115 p = .683	Log S-TfR	−0.103 p = .715	0.187 p = .505
	0.025 p = .929	−0.064 p = .822	0.356 p = .193	Log IL6	−0.213 p = .446
	0.097 p = .732	0.018 p = .950	0.765 p = .001	0.270 p = .330	Log Transferrin