Association between G-protein β3 subunit gene and isolated systolic blood pressure elevation of greater than 130 mmHg: A large-scale cross-sectional study in the Japanese population

Table 1 Characteristics of the subjects

	Male			Female
	Cases mean ± SD	Controls mean ± SD	P-value1	Cases mean ± SD	Controls mean ± SD	P-value1
Age ≤ 49 yr	n = 390	n = 1423		n = 256	n = 2917
Age, yr	37.9 ± 7.8	37.6 ± 7.7	0.53	41.4 ± 7.1	36.7 ± 8.0	< 0.001
BMI, kg/m2	24.4 ± 3.3	23.2 ± 3.1	< 0.001	23.7 ± 4.4	21.5 ± 3.1	< 0.001
SBP, mmHg	135.2 ± 6.9	114.7 ± 8.9	< 0.001	135.3 ± 6.4	109.4 ± 10.1	< 0.001
DBP, mmHg	77.6 ± 5.2	71.1 ± 7.7	< 0.001	76.2 ± 6.5	66.7 ± 8.2	< 0.001
Age ≥ 50 yr	n = 925	n = 1675		n = 1226	n = 2196
Age, yr	66.9 ± 9.8	63.3 ± 9.7	< 0.001	67.0 ± 9.7	61.8 ± 9.1	< 0.001
BMI, kg/m2	23.3 ± 3.0	22.7 ± 3.0	< 0.001	23.0 ± 3.4	22.3 ± 2.9	< 0.001
SBP, mmHg	138.7 ± 8.8	115.3 ± 9.5	< 0.001	139.4 ± 9.6	114.1 ± 10.0	< 0.001
DBP, mmHg	76.6 ± 6.1	70.5 ± 7.8	< 0.001	75.2 ± 6.7	68.8 ± 8.0	< 0.001

¹t-test. DBP: Diastolic blood pressure; BMI: Body mass index; SBP: Systolic blood pressure.

Table 2 Allele and genotype frequencies of GNB3 in the gender/age sub-categories

	Male			Female
	Cases n (%)	Controls n (%)	P-value1	Cases n (%)	Controls n (%)	P-value1
Age ≤ 49 yr
Allele
C825 (wild)	350 (44.9)	1433 (50.4)	0.007	244 (47.7)	2912 (49.9)	0.33
T825 (variant)	430 (55.1)	1413 (49.6)		268 (52.3)	2922 (50.1)
Genotype
CC	85 (21.8)	356 (25.0)	0.008	60 (23.4)	718 (24.6)	0.5
CT	180 (46.2)	721 (50.7)		124 (48.4)	1476 (50.6)
TT	125 (32.1)	346 (24.3)		72 (28.1)	723 (24.8)
HWE	χ² = 1.76, P = 0.19	χ² = 0.26, P = 0.61		χ² = 0.22, P = 0.64	χ² = 0.42, P = 0.52
Age ≥ 50 yr
Allele
C825 (wild)	903 (48.8)	1649 (49.2)	0.78	1229 (50.1)	2175 (49.5)	0.63
T825 (variant)	947 (51.2)	1701 (50.8)		1223 (49.9)	2217 (50.5)
Genotype
CC	221 (23.9)	412 (24.6)	0.92	309 (25.2)	537 (24.5)	0.88
CT	461 (49.8)	825 (49.3)		611 (49.8)	1101 (50.1)
TT	243 (26.3)	438 (26.1)		306 (25.0)	558 (25.4)
HWE	χ² = 0.01, P = 0.94	χ² = 0.36, P = 0.55		χ² = 0.01, P = 0.91	χ² = 0.02, P = 0.89

¹χ² test. HWE: Hardy-Weinberg equilibrium.

Table 3 Associations between genotypes of GNB3 and SBP ≥ 130 mmHg

	Male		Female
	Crude OR (95%CI)	Adjusted OR (95%CI)1	Crude OR (95%CI)	Adjusted OR (95%CI)1
Age ≤ 49 yr
CC	1	1	1	1
CT	1.05 (0.78-1.39)	1.09 (0.81-1.45)	1.01 (0.73-1.39)	1.01 (0.73-1.41)
TT	1.51 (1.11-2.07)	1.53 (1.11-2.10)	1.19 (0.83-1.70)	1.13 (0.78-1.63)
Age ≥ 50 yr
CC	1	1	1	1
CT	1.04 (0.85-1.27)	1.01 (0.82-1.24)	0.96 (0.81-1.15)	1.02 (0.85-1.22)
TT	1.03 (0.83-1.30)	1.03 (0.81-1.30)	0.95 (0.78-1.16)	1.01 (0.82-1.24)

¹Logistic regression analysis with adjustment for age and body mass index.