Table 3.

Telomere length and lung cancer-specific mortality among stage III/IIV small cell lung cancer cases, stratified by age, smoking status, sex, intervention arm, pack years of smoking, and time between blood draw and diagnosis.^a

Subgroup		TL tertiles	SCLC deaths	Total SCLC cases	HR	(95% CI)	P-trend
Lung cancer stage	Stage III/IV	1 (shortest)	29	29	3.32	(1.78–6.21)	0.0002
		2	28	29	1.94	(1.05–3.58)
		3 (longest)	24	28	1.00	(Ref.)
Age at blood draw	≤65 years	1 (shortest)	15	15	4.06	(1.55–10.64)	0.003
		2	15	15	2.71	(1.15–6.37)
		3 (longest)	13	15	1.00	(Ref.)
	>65 years	1 (shortest)	14	14	6.33	(1.86–21.52)	0.003
		2	13	14	2.12	(0.67–6.71)
		3 (longest)	11	13	1.00	(Ref.)
Smoking status at blood draw	Current smoker	1 (shortest)	18	18	4.77	(1.92–11.84)	0.001
		2	20	21	1.52	(0.68–3.40)
		3 (longest)	14	16	1.00	(Ref.)
	Former smoker	1 (shortest)	11	11	5.11	(1.24–20.97)	0.006
		2	8	8	15.60	(3.22–75.82)
		3 (longest)	10	12	1.00	(Ref.)
Sex	Men	1 (shortest)	17	17	2.80	(1.25–6.27)	0.01
		2	19	19	1.64	(0.70–3.84)
		3 (longest)	17	18	1.00	(Ref.)
	Women	1 (shortest)	12	12	5.06	(1.60–16.06)	0.006
		2	9	10	1.97	(0.54–7.18)
		3 (longest)	7	10	1.00	(Ref.)
Intervention arm	Active	1 (shortest)	21	21	8.95	(2.66–30.10)	0.0003
		2	15	15	2.38	(0.84–6.69)
		3 (longest)	8	11	1.00	(Ref.)
	Placebo	1 (shortest)	8	8	2.01	(0.68–5.94)	0.06
		2	13	14	2.92	(1.12–7.57)
		3 (longest)	16	17	1.00	(Ref.)
Pack years at blood draw (median=52 years)	≤52 years	1 (shortest)	13	13	3.79	(1.44–9.94)	0.006
		2	18	19	2.41	(0.97–5.99)
		3 (longest)	11	14	1.00	(Ref.)
	>52 years	1 (shortest)	16	16	3.71	(1.36–10.07)	0.01
		2	10	10	1.27	(0.46–3.46)
		3 (longest)	13	14	1.00	(Ref.)
Time between blood draw and lung cancer diagnosis (mean=5 years)	0–5 years	1 (shortest)	22	22	6.38	(2.59–15.74)	0.0001
		2	20	21	4.09	(1.68–9.93)
		3 (longest)	15	17	1.00	(Ref.)
	>5 years	1 (shortest)	7	7	2.58	(0.66–10.11)	0.18
		2	8	8	1.50	(0.38–5.86)
		3 (longest)	9	11	1.00	(Ref.)

Abbreviations: HR = hazard ratio; CI = confidence interval; TL = telomere length.

^aCox proportional hazards models adjusted for age at blood draw, sex, race, asbestos exposure, enrollment year, smoking status at blood draw, intervention arm, and pack years at blood draw (any of these adjustment variables was not included when the analysis was stratified on that variable).