TABLE 1.
Demographic characteristics of study participants in NHANES.
| Variable | (%/Mean)* |
| Age | |
| <65 | 36.42 |
| [65, 72) | 32.34 |
| ≥72 | 31.24 |
| Sex | |
| Male | 47.17 |
| Female | 52.83 |
| Race/ethnicity | |
| Non-hispanic white | 76.99 |
| Non-hispanic black | 9.32 |
| Mexican American | 3.68 |
| Other race/ethnicity | 10.01 |
| Marital status | |
| Never married | 4.63 |
| Married/living with partner | 64.90 |
| Widowed/divorced | 30.47 |
| Education | |
| Below high school | 5.65 |
| High school | 30.62 |
| College or above | 63.72 |
| Poverty income ratio | |
| <1 | 9.47 |
| [1,3) | 37.11 |
| ≥3 | 53.42 |
| BMI (kg/m2) | |
| <25 | 26.77 |
| [25, 30) | 34.41 |
| ≥30 | 38.82 |
| Smokers | |
| Never smoker | 50.96 |
| Former smoker | 37.24 |
| Current smoker | 11.80 |
| Alcohol drinkers | |
| Non-drinker | 36.11 |
| Moderate alcohol use | 57.68 |
| High alcohol use | 6.21 |
| Diabetes mellitus | |
| No | 68.81 |
| Yes | 31.19 |
| Cardiovascular diseases | |
| No | 79.42 |
| Yes | 20.58 |
| Physical exercise (100*MET-minutes/week) | 5.95 ± 0.48 |
| Sleep duration (hours/day) | 6.29 ± 0.03 |
| Score of the Animal Fluency test | 18.54 ± 0.26 |
| Score of the Digit Symbol Substitution test | 53.55 ± 0.67 |
*Weighted percentage for category variables and weighted Mean ± SE for continuous variables.
NHANES, National Health and Nutrition Examination Survey; BMI, body mass index; MET, metabolic equivalent of task.