Table 1

 Odds ratios for prevalent coronary heart disease across categories of passive smoking by self report, serum cotinine, and their combination

Self reported exposure groupSerum cotinine groupCombination score derived from self report and cotinine groups
All (n = 1854)I (n = 314)II (n = 776)III (n = 432)IV (n = 332)All (n = 1559)I (n = 368)II (n = 429)III (n = 603)IV (n = 159)I (n = 89)II (n = 298)III (n = 345)IV (n = 303)V (n = 267)VI (n = 183)VII (n = 74)
†Odds adjusted for age, sex, educational level, employment status, BMI, systolic blood pressure; ‡further adjusted for parents’ CHD history, alcohol drinking, dietary vitamin C and fibre, and serum total cholesterol.
Statistical significance: *p<0.05, **p<0.01, ***p<0.001; linear trend p: T1<0.05, T2<0.01.
Questionnaire angina
No positive9311302329762293114211141613146
Prevalence (%) T24. T22. T1
Odds ratio†* T11.00.3**0.81.4 T11.
Odds ratio‡**0.81.3 T21.
95% CI‡0.4–2.00.5–2.40.7–3.50.1–0.70.5–1.50.6–2.80.3–5.70.3–6.20.4–7.60.3–7.40.5–110.4–11
Undiagnosed CHD
No positive3004411571702546352105348455548433520
Prevalence (%) T116.317.112.117.421.4 T19.015.115.915.816.119.127.0
Odds ratio†*1.00.6**
Odds ratio‡*0.91.2 T21.*
95% CI‡0.8–1.70.8–1.91.0–2.50.4–0.90.6–1.30.7–1.90.7–3.50.8–3.90.7–3.50.7–3.60.9–4.71.2–7.3
Diagnosed CHD
No positive8593024227514193573817151985
Prevalence (%)
Odds ratio†*2.8*
Odds ratio‡*
95% CI‡0.6–3.41.0–5.80.9–5.60.5–2.20.6–2.60.3–2.50.1–2.00.3–3.70.2–3.70.4–5.40.2–4.50.2–5.3
No positive38553145959232977711404111537263624325
Prevalence (%)20.816.918.722.027.7 T221.120.916.623.225.8 T112.417.820.920.823.223.533.8 T1
Odds ratio†*2.0*** T21.*
Odds ratio‡* T11.00.7**
95% CI‡0.8–1.91.0–2.31.2–2.90.5–1.00.7–1.40.7–1.80.6–2.60.8–3.30.7–3.00.8–3.60.9–3.91.1–6.0