Directly measured secondhand smoke exposure and COPD health outcomes

BMC Pulmonary Medicine

Table 5 Prospective impact of directly measured SHS exposure on COPD-related health status at 1 year follow-up (n = 68)

SHS exposure	COPD severity		Physical health status (SF-12)		Disease-specific QOL		Dyspnea
	Bivariate	Multivariate	Bivariate	Multivariate	Bivariate	Multivariate	Bivariate	Multivariate
Urine cotinine
1^st tertile	Referent	Referent	Referent	Referent	Referent	Referent	Referent	Referent
2^nd tertile	2.8 (-1.2 to 6.7)	1.9 (-2.3 to 6.0)	0.4 (-6.3 to 7.0)	2.6 (-4.2 to 9.4)	-0.3 (-3.1 to 2.5)	-1.4 (-4.1 to 1.3)	0.1 (-0.8 to 0.6)	-0.2 (-0.8 to 0.4)
3^rd tertile	5.8 (1.5 to 10.2)	4.7 (-0.1 to 9.4)*	-7.8 (-15 to -0.6)	-5.7 (-14 to 2.0)	4.5 (1.3 to 7.6)	2.9 (-0.16 to 5.9)^†	1.2 (0.5 to 1.9)	0.9 (0.2 to 1.6)
Nicotine badge
1^st tertile	Referent	Referent	Referent	Referent	Referent	Referent	Referent	Referent
2^nd tertile	0.5 (-3.6 to 4.6)	1.0 (-3.3 to 5.3)	0.1 (-6.8 to 6.9)	-0.2 (-7.2 to 6.9)	-0.2 (-3.1 to 2.8)	0.3 (-2.5 to 3.0)	-0.1 (-0.8 to 0.6)	0 (-0.7 to 0.6)
3^rd tertile	-0.7 (-4.8 to 3.5)	-0.3 (-4.6 to 4.0)	-1.1 (-8.1 to 5.9)	-2.1 (-9.2 to 5.0)	-0.1 9–3.1 to 2.9)	0.9 (-1.9 to 3.7)	0 (-0.6 to 0.7)	0.2 (-0.5 to 0.8)

All values are mean score change compared to lowest exposure tertile (referent group) and 95% confidence interval. Multivariate analysis controls for age, sex, race, educational attainment, and past smoking history. Physical health status was measured by the SF-12 physical component summary score; Disease-specific QOL was measured by the Airways Questionnaire 20 (AQ-20); Dyspnea was measured by the modified MRC Dyspnea Scale. Higher scores = worse status, except for SF-12 physical score.
Boldface = p < 0.05.
*p = 0.054
^†p = 0.063

ISSN: 1471-2466