Serum selenoprotein P in lean and obese Egyptian individuals and its relation to insulin resistance

Figures & data

Table 1. Comparison between the two studied groups according to socio-demographic and anthropometric data

	Overweight/obesity (n = 50)	Lean (n = 40)	Test of Sig.	p value
Sex, no. (%)
Male	28 (56%)	21 (52.5%)	χ^2 = 0.110	0.740
Female	22 (44%)	19 (47.5%)
Age (years)
Min. – Max.	25–35	26–36	t = 1.554	0.124
Mean ± SD	30.46 ± 2.82	29.55 ± 2.69
Median (IQR)	31 (29–33)	29.5 (27–31.5)
Weight (kg)
Min. – Max.	85.5–111	50–65	t = 36.274	<0.001
Mean ± SD	95.22 ± 6.28	55.76 ± 3.97
Median (IQR)	95.25 (90–99)	55 (52–59.5)
Height (m)
Min. – Max.	1.51–1.76	1.54–1.75	t = 0.997	0.321
Mean ± SD	1.61 ± 0.07	1.62 ± 0.06
Median (IQR)	1.59 (1.55–1.68)	1.62 (1.58–1.67)
BMI (kg/m^2)
Min. – Max.	28.73–48.24	19.57–21.93	t = 26.039	<0.001
Mean ± SD	36.99 ± 4.25	21.16 ± 0.59
Median (IQR)	36.89 (33.56–40.28)	21.29 (20.78–21.68)
Waist circumference (cm)
Min. – Max.	95–114	65–76	U = 0	<0.001
Mean ± SD	99.42 ± 3.72	68.93 ± 2.8
Median (IQR)	99 (96–102)	70 (67–70)
Hip circumference (cm)
Min. – Max.	106–114	85–97	t = 31.232	<0.001
Mean ± SD	109.6 ± 2	90.5 ± 3.42
Median (IQR)	110 (108–111)	90 (88–92)
Waist-hip ratio
Min. – Max.	0.84–1.08	0.71–0.79	t = 20.542	<0.001
Mean ± SD	0.91 ± 0.04	0.76 ± 0.02
Median (IQR)	0.91 (0.87–0.94)	0.77 (0.75–0.78)
Waist-height ratio
Min. – Max.	0.57–0.75	0.4–0.46	U = 0	<0.001
Mean ± SD	0.62 ± 0.03	0.42 ± 0.02
Median (IQR)	0.62 (0.60–0.63)	0.42 (0.41–0.44)

t: Student t-test, U: Mann Whitney test, χ²: Chi-square test

Table 2. Comparison between the two studied groups according to clinical and laboratory data

	Overweight/obesity (n = 50)	Lean (n = 40)	Test of Sig.	p value
Systolic (mmHg)
Min. – Max.	130–135	110–120	t = 20.083	<0.001
Mean ± SD	132.3 ± 2.52	116.9 ± 4.3
Median (IQR)	130 (130–135)	120 (112.5–120)
Diastolic (mmHg)
Min. – Max.	83– 87	75– 80	t = 15.970	<0.001
Mean ± SD	85.06 ± 1.6	87.57 ± 2.14
Median (IQR)	85 (83–86)	80 (76.5–80)
Serum cholesterol (mg/dl)
Min. – Max.	155–179	130–159	t = 12.991	<0.001
Mean ± SD	166.8 ± 6.59	148.52 ± 6.71
Median (IQR)	166 (162–170)	149.5 (145–154.75)
Serum triglycerides (mg/dl)
Min. – Max.	102–148	110–147	t = 0.383	0.702
Mean ± SD	129.6 ± 11.69	128.68 ± 11.53
Median (IQR)	130 (120–140)	129.5 (116.25–139)
HDL cholesterol (mg/dl)
Min. – Max.	49–55	55–65	t = 13.826	<0.001
Mean ± SD	51.76 ± 1.84	58.85 ± 2.8
Median (IQR)	51 (50–54)	59 (56.25–60.75)
LDL cholesterol (mg/dl)
Min. – Max.	58–101	64–93	t = 0.802	0.424
Mean ± SD	78.32 ± 9.47	76.83 ± 7.84
Median (IQR)	79 (71–83)	76 (71–81.5)
Lipid accumulation product
Min. – Max.	42.61–81.32	1.26–26.42	t = 31.528	<0.001
Mean ± SD	54.97 ± 7.1	10.53 ± 6.03
Median (IQR)	54.82 (50.2–58.9)	10.55 (6.46–14.75)
Visceral adiposity index
Min. – Max.	1.07–2.09	0.87–1.9	t = 3.336	0.001
Mean ± SD	1.53 ± 0.29	1.32 ± 0.31
Median (IQR)	1.47 (1.30–1.79)	1.26 (1.07–1.57)
Atherogenic Index of Plasma
Min. – Max.	−0.06–0.12	−0.11–0.04	t = 338.5	<0.001
Mean ± SD	0.04 ± 0.04	−0.02 ± 0.04
Median (IQR)	0.04 (0.01–0.07)	−0.02 (0.06–0.01)

t: Student t-test

Table 3. Comparison between the two studied groups according to serum insulin level, insulin sensitivity, and serum selenoprotein P level

	Overweight/obesity (n = 50)	Lean (n = 40)	Test of Sig.	p value
Fasting blood sugar (mg/dl)
Min. – Max.	85–98	84–92	t = 6.441	<0.001
Mean ± SD	93.68 ± 4.25	89.03 ± 2.54
Median (IQR)	94.5 (90–98)	90 (87–91)
Serum insulin (U/mL)
Min. – Max.	18–25	5–15	t = 21.572	<0.001
Mean ± SD	21.86 ± 2.19	11 ± 2.59
Median (IQR)	22 (20–24)	11.2 (8.8–13.1)
HOMA-IR
Min. – Max.	4.18–6.05	1.05–3.37	t = 21.554	<0.001
Mean ± SD	5.06 ± 0.58	2.42 ± 0.58
Median (IQR)	4.96 (4.62–5.57)	2.5 (1.97–2.84)
Insulin sensitivity, No. (%)
Noninsulin resistant	0	17 (42.5%)	χ^2 = 26.199	<0.001
Insulin resistant	50 (100%)	23 (57.5%)
Serum selenoprotein P (mg/L)
Min. – Max.	6–20	0.1–15	U = 75.5	<0.001
Mean ± SD	16.18 ± 3.99	4.25 ± 4.27
Median (IQR)	17.65 (13.7–19)	3.4 (1.05–5)

t: Student t-test, U: Mann Whitney test, χ²: Chi-square test

Figure 1. Comparison between the two studied groups according to serum selenoprotein P concentration

Table 4. Cut-off point for serum selenoprotein P concentration (mg/L) to predict insulin resistance in the total sample

	Cut-off	Sensitivity	Specificity	PPV	NPV
Serum selenoprotein P (mg/L)	>5.3	71.23	82.35	94.5	40.0

AUC: Area Under a Curve, p value: Probability value, CI: Confidence Intervals, NPV: Negative predictive value, PPV: Positive predictive value

Figure 2. ROC curve for Serum selenoprotein P concentration (mg/L) to predict insulin resistant in total sample

Table 5. Cut-off point for visceral adiposity index to predict insulin resistance in the total sample

	Cut-off	Sensitivity	Specificity	PPV	NPV
Visceral adiposity index	>1.08	93.15	41.18	87.2	58.3

AUC: Area Under a Curve, p value: Probability value, CI: Confidence Intervals

NPV: Negative predictive value, PPV: Positive predictive value

Figure 3. ROC curve for visceral adiposity index to predict insulin resistant in total sample

Table 6. Correlation between serum selenoprotein P concentration different parameters in each group

Serum selenoprotein P concentration (mg/L)
	Overweight/obesity (n = 50)		Lean (n = 40)
	r	p		r	p
Weight (kg)	−0.019	0.893		0.211	0.192
BMI (kg/m^2)	0.118	0.413		0.236	0.143
Waist circumference (cm)	−0.453	0.001		0.115	0.480
Hip circumference (cm)	0.464	0.001		0.154	0.342
Waist-hip ratio	−0.506	<0.001		−0.070	0.668
Waist-height ratio	−0.195	0.175		0.004	0.982
Lipid accumulation product	−0.057	0.695		−0.078	0.634
F.B.S (mg/dl)	0.126	0.382		0.011	0.948
Serum insulin concentration (U/mL)	0.585	<0.001		−0.235	0.145
HOMA-IR	0.570	<0.001		−0.225	0.162
Serum cholesterol (mg/dl)	0.094	0.515		0.269	0.093
HDL cholesterol (mg/dl)	−0.207	0.150		0.046	0.777
Systolic BP (mmHg)	0.138	0.338		0.049	0.766
Diastolic BP (mmHg)	0.198	0.167		0.049	0.766
Visceral adiposity index	0.323	0.022		−0.170	0.293
Atherogenic Index of Plasma	0.129	0.37		−0.011	0.947

r: Pearson coefficient

Table 7. Univariate and multivariate analysis for the parameters affecting Serum selenoprotein P concentration in overweight/obesity (n = 50)

Serum selenoprotein P concentration	Univariate		^#Multivariate
	r	p	B (95%C.I)	p
Weight (kg)	−0.019	0.893
BMI (kg/m^2)	0.118	0.413
Waist circumference (cm)	−0.453	0.001*	−2.039(−4.385– 0.307)	0.087
Hip circumference (cm)	0.464	0.001*	2.006(0.023– 3.989)	0.048*
Waist-hip ratio	−0.506	<0.001*	193.048(−50.585– 436.682)	0.117
Waist-height ratio	−0.195	0.175
Lipid accumulation product	−0.057	0.695
F.B.S (mg/dl)	0.126	0.382
Serum insulin concentration (U/mL)	0.585	<0.001*	1.220(0.227– 2.214)	0.017*
HOMA-IR	0.570	<0.001*	−1.276(−5.112– 2.560)	0.506
Serum cholesterol (mg/dl)	0.094	0.515
HDL cholesterol (mg/dl)	−0.207	0.150
Systolic BP (mmHg)	0.138	0.338
Diastolic BP (mmHg)	0.198	0.167
Visceral adiposity index	0.323	0.022*	1.437(−2.121– 4.994)	0.420
Atherogenic Index of Plasma	0.129	0.370

r: Pearson coefficient, B: Unstandardized Coefficients, C.I.: Confidence interval *: Statistically significant at p ≤ 0.05