Interleukin-18 gene polymorphism and markers of subclinical atherosclerosis. The Cardiovascular Risk in Young Finns Study

Figures & data

Table I. Characteristics of the study population.

Variable	All (n = 2260)	Male (n = 1013)	Female (n = 1247)	P-value^a
Age (years)	31.7 ± 5.0	31.7 ± 5.0	31.7 ± 5.0	0.933
Body mass index (kg/m^2)	24.91 ± 4.16	25.69 ± 3.79	24.27 ± 4.33	<0.001
Ever smokers, yes (%)^b	959 (42.4)	493 (48.7)	466 (37.4)	<0.001
Systolic BP (mmHg)	122.0 ± 14.4	129.2 ± 13.5	116.2 ± 12.4	<0.001
Diastolic BP (mmHg)	73.16 ± 9.0	74.99 ± 9.1	71.67 ± 8.7	<0.001
Cholesterol (mmol/L)	5.16 ± 0.98	5.26 ± 1.03	5.09 ± 0.93	<0.001
HDL cholesterol (mmol/L)	1.29 ± 0.32	1.16 ± 0.28	1.40 ± 0.31	<0.001
LDL cholesterol (mmol/L)	3.27 ± 0.85	3.42 ± 0.92	3.16 ± 0.78	<0.001
Triglycerides (mmol/L)	1.34 ± 0.85	1.53 ± 0.99	1.18 ± 0.68	<0.001
Apolipoprotein A-l (g/L)	1.50 ± 0.26	1.40 ± 0.21	1.57 ± 0.27	<0.001
Apolipoprotein B (g/dL)	1.06 ± 0.26	1.13 ± 0.27	1.00 ± 0.24	<0.001
Insulin (mU/L)	7.63 ± 5.21	7.52 ± 5.19	7.72 ± 5.22	0.382
Glucose (mmol/L)	5.00 ± 0.45	5.15 ± 0.42	4.87 ± 0.44	<0.001
C-reactive protein (mg/L)	1.89 ± 3.85	1.46 ± 3.27	2.23 ± 4.23	<0.001
Homocysteine (μmol/L)	9.82 ± 3.81	10.86 ± 4.18	8.97 ± 3.24	<0.001

Values of continuous variables are expressed as mean ± standard deviation.

^aSignificance calculated using one-way ANOVA for continuous variables and Pearson's chi-square test for categorical variables.

^bThis category includes daily smokers, ex-daily smokers, and occasional smokers.

BP = blood pressure; HDL = high-density lipoprotein; LDL = low-density lipoprotein.

Table II. Interleukin-18 (IL-18) genotype distributions.

	IL-18 genotype, n (%)
SNP, rs number	Major homozygote	Heterozygote	Minor homozygote
–656 (C/a), rsl946519	673 (30.0%)	1065 (47.1%)	506 (22.5%)
+ 127 (C/t), rs360717	1125 (50.8%)	899 (40.6%)	189 (8.5%)
+35 (T/g), rs549908	1062 (47.2%)	966 (42.9%)	223 (9.9%)
+415 (A/g), rs5744292	1204 (57.6%)	766 (36.6%)	121 (5.8%)
+ 533 (T/c)^a, rs4937100	1195 (53.4%)	704 (31.4%)	340 (15.2%)

^aGenotype distribution not in Hardy-Weinberg equilibrium.

SNPs = single nucleotide polymorphisms.

Table III. Interleukin-18 (IL-18) haplotypes.

	IL-18 SNPs
	–656(C/a) rs 1946519	+ 127 (C/t) rs360717	+35(T/g) rs549908	+415(A/g) rs5744292	+ 533(T/c) rs4937100	Haplotype frequency	(SE)
Haplotype	C	C	T	A	c	0.270	(0.0005)
	a	t	g	A	T	0.288	(0.0003)
	C	c	T	g	T	0.244	(0.0003)
	a	c	T	A	T	0.132	(0.0005)
	C	c	g	A	T	0.024	(0.0001)
	a	c	T	A	c	0.041	(0.0004)
Minor allele frequency	0.462	0.288	0.313	0.240	0.312

SNPs = single nucleotide polymorphisms.