Table 5.

Differences in overall survival associated with immunotherapy in smoking status by subgroups.

		Participants, no.		Pooled HR (95% CI) for ICI vs. controlled therapies		Test for difference
Variable	Studies, no.	Smoker	Never smoker	Smoker	Never smoker	P value
Overall	15	8679	1439	0.77 (0.71, 0.83)	0.85 (0.70, 1.03)	0.335
Line of therapy
First	10	5861	965	0.78 (0.71, 0.87)	0.80 (0.63, 1.01)	0.881
Subsequent	5	2818	474	0.74 (0.68, 0.82)	0.93 (0.60, 1.45)	0.334
Intervention therapy
ICI alone	10	5743	1020	0.75 (0.69, 0.83)	0.99 (0.81, 1.21)	0.019
ICI combined with non-ICI	5	2936	419	0.79 (0.70, 0.90)	0.67 (0.48, 0.92)	0.032
Pathologic types
Squamous	2	877	55	0.73 (0.50, 1.07)	0.85 (0.43, 1.68)	0.701
Nonsquamous	5	2767	482	0.76 (0.67, 0.86)	0.70 (0.50, 0.97)	0.626

Abbreviations: HR = hazard ratio; ICI= immune checkpoint inhibitor.