Table 1.
Definitions and descriptive statistics of study population.
| Variables | Definitions | Mean a
(n = 9424) |
|---|---|---|
| Sodium intake | The quantity of sodium intake per day (mg/day) | 4533.17 ± 30.24 |
| Potassium intake | The quantity of potassium intake per day (mg/day) | 3104.64 ± 15.97 |
| Sodium to potassium ratio | The quantity of sodium intake divided by the quantity of potassium intake (Na/K) | 1.54 ± 0.01 |
| Hypertension (%) | 1 if systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or currently taking hypertension medications, 0 otherwise. | 19.56 |
| Body mass index | The body weight divided by the square of height (kg/m2) | 22.87 ± 0.03 |
| Walking exercise | Time spent walking per day (hours/day) | 0.67 ± 0.01 |
| Smoking status (%) | 1 if a subject is currently smoking, 0 otherwise | 14.51 |
| Drinking status (%) | 1 if a subject drinks a glass or more/month for the last 1 year, 0 otherwise | 53.28 |
| Daily stress level (%) | 1 if a subject reports “high” or “very high” levels of usual stress, 0 otherwise | 24.49 |
| Use of nutrition label (%) | 1 if a subject reads the nutrition label, 0 otherwise | 30.19 |
| Family history of hypertension (%) | 1 if a subject’s father, mother, or siblings have ever been diagnosed with hypertension, 0 otherwise | 37.37 |
| Female (%) | 1 if sex is female, 0 otherwise | 68.19 |
| Age | Age (years) | 46.12 ± 0.16 |
| Marital status (%) | 1 if unmarried, 0 otherwise | 15.86 |
| Manual worker (%) | 1 if a subject has a manual job, 0 otherwise | 22.50 |
| Household Income | Monthly household income (million won/month) | 446.57 ± 8.05 |
| Education | Schooling year: elementary school graduation = 6, middle school graduation = 9, high school graduation = 12, university = 16 | 12.30 ± 0.04 |
a All values for continuous variables were expressed as the mean ± standard deviation or the percentage for categorical variables.