Table 1. Mean relative telomere length by selected characteristics.

Selected Characteristics 1	N	%	Mean RTL 2	SE 2	P 2 , 3
Total	568	100.0	1.09	0.02	-
Age at blood draw
31–51	147	25.9	1.12	0.05
52–58	136	23.9	1.20	0.05
59–68	154	27.1	1.05	0.04
69–94	131	23.1	0.97	0.05	0.01
Race
White	541	97.8	1.09	0.02
Black	8	1.4	1.09	0.20
Other	4	0.7	0.79	0.28	0.56
State of Residence
North Carolina	283	49.8	1.12	0.03
Iowa	285	50.2	1.06	0.03	0.21
Education
High school or less	274	49.5	1.09	0.03
More than high school	279	50.5	1.08	0.03	0.89
Cigarette smoking
Never	325	57.4	1.06	0.03
Former	184	32.5	1.03	0.13
Current	40	7.1	1.15	0.09
Not regular	17	3.0	1.08	0.09	0.31
Drank alcohol last year
Never	212	37.4	1.13	0.04
Ever	355	62.6	1.12	0.03	0.16
Body Mass Index (kg/m 2 )
<18.5	1	0.2	-	-
18.5–24	103	18.2	1.05	0.06
25–29	283	50.0	1.08	0.03
≥30	179	31.6	1.12	0.04	0.12

¹Selected characterisitics ascertained at last follow-up, except age at blood draw

²Age at blood draw

³F-test for difference in mean using natural log of TL