Table 1.

Selected Characteristics of Participants

Characteristic	Total Sample (N = 1910)	African American (n = 652)	White (n = 1258)
Age, %a
45–54 y	43	36	47
55–64 y	33	35	32
≥65 y	24	29	21
Female, %a	69	72	68
High school graduate, %a	69	62	73
Health insurance, %a	93	89	94
Days of insomnia,  mean ±SD	165 ± 139	158 ± 139	169 ± 139
Days of insufficent  sleep, mean ±SD	172 ± 136	178 ± 132	169 ± 138
Symptomatic hip or  knee osteoarthritis, %	30	33	29
Obese, %a,b	48	58	43
Depressive symptoms,  %a,c	16	21	14
Fair or poor general  health, %a	32	39	29
Any type of sleep  medication use, %a	31	25	35
Prescription sleep  medication use, %a	17	14	19
Nonprescription sleep  medication use, %a	12	10	13

^aSignificantly different according to race (p < 0.05).

^bBody mass index ≥30.

^cCenter for Epidemiologic Studies Depression Scale ≥16.

Missing data: 15 for age, 1 for sex and general health, 7 for prescription or nonprescription medication use, 10 for annual days of sleep problems.