Environmental tobacco smoke exposure and heart disease: A systematic review

Table 5 Dose-response evidence for heart disease among never smokers in relation to smoking by the spouse or household members in adulthood

Study No.	Ref.1	Sex	Exposure grouping	Relative risks by grouping2	Significance (trend)3
Smoking by the spouse
1	Hirayama[29]	F	0, 1-19, 20+ (cigs/d)	1.00, 1.10, 1.314	+
5	Svendsen et al[33]	M	0, 1-19, 20+ (cigs/d)	1.00, 1.20, 1.75
14	La Vecchia et al[42]	M + F	0, 1-14, 15+ (cigs/d)	1.00, 1.13, 1.30
15	Layard[25]	M	0, 1-14, 15-34, 35+ (cigs/d)	1.00, 0.76, 1.07, 0.92
		F	0, 1-14, 15-34, 35+ (cigs/d)	1.00, 0.85, 1.15, 1.06
16	Le Vois et al[26] (CPS I)	M	0, 1-19, 20-39, 40+ (cigs/d)	1.00, 0.99, 0.98, 0.72
		F	0, 1-19, 20-39, 40+ (cigs/d)	1.00, 1.04, 1.06, 0.95
20	Steenland et al[46]	M	0, 1-19, 20, 21+ (cigs/d)	1.00, 1.33, 1.17, 1.09
		F	0, 1-19, 20, 21-39, 40+ (cigs/d)	1.00, 1.15, 1.07, 0.99, 1.04
		M	0, 1-12, 13-21, 22-29, 30+ (year)	1.00, 1.14, 1.13, 1.14, 1.25
		F	0, 1-14, 15-25, 26-33, 34+ (year)	1.00, 0.84, 0.99, 1.20, 1.20
		M	0, 1-5, 6-14, 15-27, 28+ (pack year)	1.00, 1.25, 1.33, 1.13, 1.00
		F	0, 1-12, 13-25, 26-33, 34+ (pack year)	1.00, 0.83, 1.12, 1.09, 1.26
21	Janghorbani et al[47]	F	0, 1-30, 31+ (year)	1.00, 1.74, 0.85
		F	0, 1-19, 20+ (cigs/d)	1.00, 1.76, 1.11
		F	0, 1-10, 11+ (pack year)	1.00, 1.95, 1.17
23	Ciruzzi et al[49]	F	0, 1-20, 21+ (cigs/d)	1.00, 0.82, 3.00
26	He et al[52]	F	0, 1-10, 11-20, 21+ (cigs/d)	1.00, 0.93, 1.40, 3.20	+
			0-5, 6-15, 16-30, 31+ (year)	1.00, 0.80, 2.10, 2.30	+
			0, 1-399, 400-799, 800+ (cigs/day × year)	1.00, 1.20, 1.90, 3.60	+
28	Rosenlund et al[54]	M + F	0, 1-19, 20+ (cigs/d)	1.00, 1.02, 1.58
		M + F	0, 1-32, 33+ (year)	1.00, 1.11, 1.25
		M + F	0, 1-20, 21+ (pack-year)	1.00, 1.09, 1.33
30	Enstrom et al[27]	M	0, 1-9, 10-19, 20, 21-39, 40+ (cigs/d)	1.00, 0.98, 0.82, 0.89, 1.13, 1.24
		F	0, 1-9, 10-19, 20, 21-39, 40+ (cigs/d)	1.00, 1.03, 0.99, 1.02, 0.88, 0.80
39	Wen et al[64]	F	0, < 8.8, 8.8-17.9, 18.0+ (pack-year)	1.00, 1.10, 1.12, 1.225
47	Gallo et al[71]	M + F	0, 0.5, 1.0, 1.5+ (packs/d)	1.00, 1.87, 1.89, 2.466
Smoking by household members
8	Hole et al[36]	F	0, 1-14, 15+ (cigs/d)	1.00, 2.09, 4.12	+
9	Jackson[37]	M	None, low, high (exposure)	1.00, 1.30, 0.90
		F	None, low, high (exposure)	1.00, 2.10, 7.50	+
18	Muscat et al[44]	M	None, 1-20, 21-30, 31+ (year)	1.0, 1.7, 1.5, 1.1
		F	None, 1-20, 21-30, 31+ (year)	1.0, 2.0, 0.9, 1.7
22	Kawachi et al[48]	F	None, occasional, regular	1.00, 1.19, 2.11	+
		F	< 1, 1-9, 10-19, 20-29, 30+ (year)	1.00, 1.19, 1.54, 1.11, 1.50
27	Iribarren et al[53]	M	0, 1-9, 10-39, 40+ (h/wk)	1.00, 1.12, 1.26, 1.20	+
		F	0, 1-9, 10-39, 40+ (h/wk)	1.00, 1.21, 1.31, 1.36	+
29	Pitsavos et al[55]	M + F	0, 1-4, 5-9, 10-19, 20-29, 30-39, 40+ (years living with a regular smoker)	1.00, 1.07, 1.16, 1.39, 1.75, 2.20, 3.09	+
34	McGhee et al[59]	M + F	0, 1, 2+ (smokers in the home)	1.00, 1.26, 1.68	+
40	Eisner et al[65]	M + F	Per 10 years exposure	1.10
46	Ding et al[70]	F	0, < 1, 1+ (packs/d)	1.00, 1.14, 1.69	+
			0, < 5, 5+, (year)	1.00, 1.26, 1.52	+
			0, < 4, 4+, (h/d)	1.00, 1.28, 1.82	+
			0, < 5, 5+, (pack-year)	1.00, 1.44, 1.53	+
			0, < 20, 20+ (h-year)	1.00, 1.22, 1.61	+
47	Gallo et al[71]	M + F	0, < 1, 1-2, 3+ (h/d)	1.00, 1.39, 2.08, 1.946	+
54	Iversen et al[78]	M	0, < 10, 10-19, 20-29, 30+ (year)	1.00, 0.70, 1.20, 0.70, 1.10
		F	0, < 10, 10-19, 20-29, 30+ (year)	1.00, 1.00, 1.40, 1.30, 1.60	+

¹First author of paper;

²Relative risks are adjusted for covariates if adjusted data are available;

³Significant (P < 0.05) positive (negative) trends are indicated by + (or -). Blank entries indicate non-significance. The trend test includes the unexposed group. Significant trends excluding the unexposed group are only evident for study 26 (all exposed indices);

⁴The 1-19 cigs/d group includes ex-smokers. Estimates are adjusted for the age of the husband. Alternative estimates, adjusted for the age of the subject are also given by Hirayama[115];

⁵Results for CVD. Not available for CVD - Stroke;

⁶Results for CVD. Not available for IHD. M: Male; F: Female; CVD: Cardiovascular disease; IHD: Ischaemic (coronary) heart disease.