Table 1.

Baseline characteristics of women in the Southern Community Cohort Study, 2002–2009

	Weekday sleep duration, hr					p-value
	<6	6	7	8	≥9
N (%)	7503 (17.5)	10296 (24.0)	7303 (17.1)	12072 (28.2)	5666 (13.2)
Age, yr, mean (SD)	51.2 (8.2)	52.3 (8.8)	53.0 (9.1)	52.4 (9.1)	51.7 (8.9)	<.0001
BMI, kg/m2, mean (SD)	32.6 (8.4)	32.1 (8.0)	31.5 (7.8)	31.5 (7.9)	32.2 (8.5)	<.0001
White, non-Hispanic, %	26.4	27.6	33.0	26.2	22.0	<.0001
Black, non-Hispanic, %	68.6	67.6	63.0	70.1	73.9	<.0001
College or post college, %	9.1	14.0	17.3	12.0	8.1	<.0001
Married, %	28.0	33.0	36.7	32.2	29.9	<.0001
Household income <$15,000, %	62.1	51.5	47.1	57.0	64.3	<.0001
Family history of any cancer, %	23.4	23.9	23.0	23.5	20.6	<.0001
Current smoker, %	37.2	32.7	27.9	33.4	38.5	<.0001
Nulliparous, %	9.7	10.0	10.7	10.6	10.9	0.002
Age at menarche<=12, %	49.1	48.7	47.4	45.2	42.1	<.0001
Post-menopausal, %	68.0	68.5	68.6	65.5	63.2	<.0001
MHT use, %	27.4	30.0	32.0	25.9	24.1	<.0001
Diabetes, %	24.4	22.2	21.5	22.8	25.9	<.0001
MVPA, MET hr/d, mean (SD)	13.6 (14.4)	13.7 (13.5)	13.0 (12.1)	13.0 (12.6)	12.1 (12.5)	<.0001
Multivitamin use, %	37.2	41.6	45.7	39.4	36.8	<.0001
Alcohol consumption, 1+ drink/d, %	11.4	10.5	9.9	12.1	14.1	<.0001
Dietary intakes, mean (SD)
total calories	2300 (1329)	2164 (1202)	2087 (1136)	2250 (1285)	2391 (1349)	<.0001
total fat, gram/kcal	38.1 (7.0)	38.2 (6.7)	38.0 (6.6)	38.0 (6.7)	38.3 (6.9)	0.31
total fiber, gram/kcal	9.0 (3.2)	9.2 (3.1)	9.5 (3.2)	9.2 (3.2)	8.9 (3.1)	<.0001
total folate, mg/kcal	208 (64)	212 (64)	218 (65)	215 (64)	209 (62)	<.0001

Abbreviations: MET, metabolic equivalent; MHT, menopausal hormone therapy; MVPA, moderate-to-vigorous physical activity; SD, standard deviation