Table 1

Inclusion/exclusion criteria for normal blood pressure participants

Inclusion criteriaExclusion criteria
  1. Local resident for more than 5 years

  2. Age 35–70 years

  3. Han nationality

  4. Independent individuals

  5. Those from the same community where patients with primary hypertension were selected

  6. SBP <140 mm Hg and DBP <90 mm Hg, without antihypertensive treatment

  7. Willingness to volunteer to participate in the trial and sign the informed consent form

  1. Use of any antihypertensive drug in the previous 24 hours

  2. Clinical diagnosis of cardiovascular disease, kidney disease, liver disease or malignant tumour

  3. Pregnant women

  4. Self-adherence to a low-sodium diet

  5. Inability or unwillingness to participate in the study or sign the informed consent form

  • DBP, diastolic blood pressure; SBP, systolic blood pressure.