Table 1 Characteristics of white participants in the NHIS study (1977-2009)
From: Differential increase in prevalence estimates of inadequate sleep among black and white Americans
Characteristics | 1977 | 1983 | 1985 | 1990 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 |
|---|---|---|---|---|---|---|---|---|---|---|
N | 16,429 | 8,576 | 23,756 | 29,028 | 19,357 | 19,510 | 14,089 | 13,720 | 12,814 | 16,281 |
Gender, Female (%) | 54.2 | 55.8 | 51.3 | 51.2 | 49.9 | 49.9 | 49.5 | 49.3 | 49.5 | 49.8 |
Age, years (mean ± SD) | 42 ± 15 | 40 ± 15 | 40 ± 17 | 41 ± 17 | 42 ± 17 | 42 ± 17 | 42 ± 17 | 43 ± 18 | 43 ± 18 | 43 ± 19 |
Education, ≥ HS (%) | 73.0 | 78.6 | 81.2 | 83.5 | 88.1 | 88.3 | 87.7 | 88.7 | 88.5 | 88.8 |
Marital status (%) | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Married | 74.5 | 69.6 | 69.5 | 69.6 | 62.1 | 61.8 | 60.9 | 59.9 | 59.3 | 57.9 |
 Widowed, Divorced & Separated | 12.3 | 13.0 | 11.7 | 12.6 | 15.2 | 15.3 | 15.7 | 15.5 | 16.1 | 16.4 |
 Single | 13.2 | 17.4 | 18.8 | 17.8 | 22.7 | 22.9 | 23.4 | 24.6 | 24.6 | 25.7 |
Total family income, ≥ 35K (%) | -- | 23.7 | 32.0 | 48.3 | 66.6 | 67.8 | 67.9 | 71.5 | 72.9 | 72.5 |
Poverty status, below (%) | -- | 6.6 | 8.8 | 7.3 | 9.1 | 9.0 | 10.2 | 9.5 | 10.3 | 10.8 |
Ever smoked, yes (%) | 58.8 | 56.3 | 56.5 | 52.5 | 44.2 | 44.3 | 44.0 | 43.7 | 44.2 | 44.6 |
Alcohol consumption | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Never drinkers | -- | -- | -- | 13.0 | 19.6 | 19.0 | 19.6 | 18.3 | 16.3 | 15.3 |
 Former drinkers | -- | -- | -- | 9.0 | 13.2 | 12.8 | 12.9 | 13.1 | 12.4 | 13.1 |
 Current drinkers | -- | -- | -- | 78.0 | 67.2 | 68.2 | 67.5 | 68.6 | 71.2 | 71.5 |
Body mass index (mean ± SD) | 24.3 ± 4.3 | 24.4 ± 4.5 | 24.6 ± 5.1 | 25.0 ± 5.1 | 26.6 ± 5.6 | 26.8 ± 5.7 | 27.1 ± 6.4 | 27.0 ± 6.3 | 27.3 ± 6.4 | 27.3 ± 6.8 |
Obesity (BMI ≥ 30 kg/m2) | 9.1 | 10.3 | 10.8 | 12.9 | 22.9 | 23.9 | 25.7 | 25.5 | 26.8 | 26.8 |
Physical activity, yes (%) | -- | -- | -- | -- | 10.9 | 11.4 | 11.2 | 11.3 | 11.5 | 12.5 |
Emotional stress, yes (%) | -- | -- | -- | -- | 3.3 | 3.0 | 3.1 | 2.7 | 3.6 | 3.5 |
Comorbid conditions: | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Diabetes | -- | 3.4 | -- | -- | 5.9 | 6.5 | 6.6 | 6.2 | 7.1 | 7.9 |
Hypertension | -- | 20.7 | 21.4 | 19.9 | 20.3 | 20.4 | 22.3 | 22.0 | 23.9 | 23.4 |
Cancer | -- | 3.2 | -- | -- | 5.5 | 6.1 | 5.8 | 6.1 | 6.6 | 6.8 |
Coronary heart disease | -- | 1.8 | -- | -- | 2.7 | 3.1 | 2.9 | 2.9 | 2.7 | 3.2 |
Heart attack (MI) | -- | -- | -- | -- | 2.2 | 2.4 | 2.3 | 2.1 | 2.5 | 2.3 |
Stroke | -- | 0.9 | 1.2 | 1.2 | 1.5 | 1.2 | 1.4 | 1.5 | 1.8 | 1.6 |
Kidney disease | -- | -- | -- | -- | 1.2 | 1.2 | 1.1 | 1.0 | 1.2 | 1.4 |
Sleep measures: | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Hours of sleep (mean ± SD) | 7.4 ± 1.2 | 7.3 ± 1.2 | 7.4 ± 1.4 | 7.3 ± 1.4 | 7.1 ± 1.4 | 7.1 ± 1.5 | 7.1 ± 1.3 | 7.1 ± 1.4 | 7.1 ± 1.5 | 7.1 ± 1.7 |
Categories of sleep quantity | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Very short sleep | 1.5 | 1.7 | 1.1 | 1.4 | 2.0 | 2.1 | 2.1 | 1.8 | 2.3 | 2.3 |
 Short sleep | 19.3 | 20.1 | 20.2 | 22.3 | 26.0 | 26.0 | 26.2 | 24.7 | 25.6 | 25.4 |
 Normal sleep | 68.0 | 69.0 | 68.7 | 68.2 | 64.9 | 64.9 | 64.9 | 66.9 | 64.9 | 64.5 |
 Long sleep | 11.2 | 9.1 | 10.0 | 8.1 | 7.0 | 7.0 | 6.8 | 6.6 | 7.2 | 7.8 |