Hem 7200

Standard questionnaires were used to collect participants’ information on demographics, geographic location, medical history and socioeconomic status by trained interviewers in accordance with standard procedures. After at least 5 min sitting rest, the blood pressure (BP) of the participants was measured three times by a trained interviewer at 45-s intervals using a digital sphygmomanometer (Omron TM HEM-7200). A digital weighing scale (Omron Corporation, HN-286) and a stadiometer (Seca Corporation, 213) were used to measure body mass and height to within 0.1 kg and 0.1 cm, respectively, while the participants were wearing lightweight clothes and no shoes. BMI (kg/m²) was calculated as the following formula: BMI = body mass/height².
After an overnight fast, three tubes of venous blood were collected from the participants by professional staff, and parameters were measured according to standard procedures. Fasting blood glucose (FBG) and serum lipid parameters were measured using enzymatic colorimetric assays. Blood urea nitrogen (BUN) was measured using an enzymatic UV method involving urease. The serum creatinine and uric acid concentrations and glycosylated hemoglobin A1c (HbA1c) were measured using the rate-blanked and compensated Jaffe creatinine method, the UA Plus method, and boronate-affinity high-performance liquid chromatography, respectively.

Seated BP for each participant was taken three times at 45-second intervals using Omron digital devices (Omron model HEM-7200) in the CHARLS [17 (link)]. Similarly, seated BP was taken thrice at one-minute intervals after five minutes of rest, but was measured by a mercury sphygmomanometer in the NHANES [18 ].
We defined treated hypertension as participants taking medicines for the management of hypertension and untreated hypertension if they were not taking medicines, but had hypertension.

Height and weight were measured to the nearest 1 cm and 0.1 kg, respectively. Body mass index (BMI) was calculated [formula: BMI = body weight (kg)/height² (m²)]. Waist circumference and hip circumference (to the nearest 1 cm) were measured, and waist-to-hip ratio (WHR) was calculated [formula: WHR = waist circumference (cm)/hip circumference (cm)]. Blood pressure and pulse rates were measured in the sitting position using electronic sphygmomanometer Omron, HEM-7200 (Omron Inc., Tokyo, Japan). Body fat percentage was detected using electronic body fat measuring instrument Omron, HBF-375 (Omron Inc., Tokyo, Japan). Bone mineral densities at the lumbar spine (L₂–L₄) and femoral neck were measured by dual X-ray absorptiometry (DXA, GE-Lunar Prodigy, Waukesha, WI, USA).