Table 4

Synergistic effect of ACE I/D DD genotype and classical risk factors in CAD patients and controls
Classical risk factor
 ACE I/D DD
 Whole population
 Males
 Females
 ≤ 45 subgroup


CAD
 Control
 OR(95%CI)
 CAD
 Control
 OR(95%CI)
 CAD
 Control
 OR(95%CI)
 CAD
 Control
 OR(95%CI)


Hypertension












0
 0
 63
 256
 1
 54
 143
 1
 9
 113
 1
 24
 132
 1
0
 1
 43
 99
 1.76(1.10–2.84)*
 39
 43
 2.40(1.36–4.25)**
 4
 56
 0.90(0.22–3.38)NS
 11
 55
 1.10(0.47–2.55)NS
1
 0
 112
 110
 4.14(2.78–6.17)***
 83
 82
 2.68(1.69–4.25)***
 29
 28
 13.00(5.16–33.64)***
 12
 20
 3.30(1.32–8.25)*
1
 1
 80
 45
 7.22(4.46–11,73)***
 59
 27
 5.79(3.22–10.46)***
 21
 18
 14.65(5.33–41.40)***
 17
 4
 23.38(6.59–90.92)***


SI = 1.59; SIM = 0.99; RERI = 2.32;
AP = 0.32
 SI = 1.56; SIM = 0.90; RERI = 1.71;
AP = 0.30
 SI = 1.15; SIM = 1.25; RERI = 1.75;
AP = 0.12
 SI = 9.32; SIM = 6.44; RERI = 19.98;
AP = 0.85
Smoking












0
 0
 112
 269
 1
 76
 153
 1
 36
 116
 1
 11
 106
 1
0
 1
 70
 104
 1.62(1.09–2.39)*
 48
 47
 2.06(1.23–3.45)*
 22
 57
 1.24(0.64–2.41)NS
 9
 37
 2.34(0.81–6.72)NS
1
 0
 63
 97
 1.56(1.04–2.34)*
 61
 72
 1.71(1.07–2.71)*
 2
 25
 0.26(0.04–1.21)NS
 25
 46
 5.24(2.24–12.46)***
1
 1
 53
 40
 3.18(1.95–5.21)***
 50
 23
 4.38(2.40–8.02)***
 3
 17
 0.57(0.12–2.23)NS
 19
 22
 8.32(3.21–21.96)***


SI = 1.85; SIM = 1.26; RERI = 1.00;
AP = 0.31
 SI = 1.91; SIM = 1.24; RERI = 1.61;
AP = 0.37
 SI = 0.86; SIM = 1.77; RERI = 0.07;
AP = 0.13
 SI = 1.31; SIM = 0.68; RERI = 1.74;
AP = 0.21
Obesity












0
 0
 126
 295
 1
 99
 180
 1
 27
 115
 1
 30
 135
 1
0
 1
 88
 122
 1.69(1.18–2.42)**
 72
 59
 2.22(1.42–3.46)**
 16
 63
 1.08(0.51–2.27)NS
 22
 55
 1.80(0.91–3.55)NS
1
 0
 49
 71
 1.62(1.04–2.51)*
 38
 45
 1.54(0.91–2.60)NS
 11
 26
 1.80(0.73–4.39)NS
 6
 17
 1.59(0.51–4.77)NS
1
 1
 35
 22
 3.72(2.03–6.87)***
 26
 11
 4.30(1.93–9.71)***
 9
 11
 3.48(1.18–10.24)*
 6
 4
 6.75(1.56–30.78)*


SI = 2.07; SIM = 1.36; RERI = 1.41;
AP = 0.38
 SI = 1.88; SIM = 1.26; RERI = 1.54;
AP = 0.36
 SI = 2.82; SIM = 1.79; RERI = 1.60;
AP = 0.46
 SI = 4.13; SIM = 2.36; RERI = 4.36;
AP = 0.65
Diabetes












0
 0
 123
 342
 1
 101
 208
 1
 22
 134
 1
 31
 151
 1
0
 1
 89
 134
 1.85(1.30–2.63)**
 75
 61
 2.53(1.64–3.91)***
 14
 73
 1.17(0.53–2.56)NS
 25
 59
 2.06(1.08–3.95)*
1
 0
 52
 24
 6.02(3.46–10.55)***
 36
 17
 4.36(2.25–8.54)***
 16
 7
 13.92(4.69–42.75)***
 5
 1
 24.35(2.61–570.81)**
1
 1
 34
 10
 9.45(4.33–21.12)***
 23
 9
 5.26(2.22–12.78)***
 11
 1
 67.00(8.19–1458.07)***
 3
 0
 --


SI = 1.44; SIM = 0.85; RERI = 2.58;
AP = 0.27
 SI = 0.87; SIM = 0.47; RERI = -0.63;
AP = -0.12
 SI = 5.04; SIM = 4.11; RERI = 52.91;
AP = 0.79
 --

Dyslipidaemia












0
 0
 52
 327
 1
 47
 197
 1
 5
 130
 1
 16
 144
 1
0
 1
 35
 123
 1.79(1.08–2.96)*
 31
 57
 2.28(1.28–4.05)**
 4
 66
 1.58(0.34–7.05)NS
 6
 58
 0.93(0.31–2.70)NS
1
 0
 123
 39
 19.83(12.16–32.47)***
 90
 28
 13.47(7.68–23.77)***
 33
 11
 78.00(22.86–287.79)***
 20
 8
 22.50(7.80–67.21)***
1
 1
 88
 21
 26.35(14.58–48.04)***
 67
 13
 21.60(10.54–45.02)***
 21
 8
 68.25(18.00–282.98)***
 22
 1
 198.00(25.16–4210.95)***


SI = 1.29; SIM = 0.74; RERI = 5.73;
AP = 0.22
 SI = 1.50; SIM = 0.70; RERI = 6.85;
AP = 0.32
 SI = 0.87; SIM = 0.55; RERI = -10.33;
AP = -0.15
 SI = 9.19; SIM = 9.46; RERI = 175.57;
AP = 0.89

SI, Rothman's synergy index for interaction; RERI, relative excess risk due to interaction; AP, proportion of disease attributable to interaction; *P < 0.05, **P < 0.005, ***P < 0.0001, NS not significant P > 0.05.

Freitas et al. BMC Cardiovascular Disorders 2008 8:15   doi:10.1186/1471-2261-8-15