Automated analyzer

Venous blood samples were collected from children following an overnight fast for 12 h. Serum was separated by centrifugation at 1500×g for 15 min at 4°C within 2 h and stored at −80°C until testing. Serum levels of triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), TC and HDL-C were examined using commercial colorimetric kits (Biosino Biotechnology Company Ltd, Beijing, China) and an automated analyzer (Hitachi Co Ltd) in accordance with previous document [12 (link)]. The inter- and intra- assay coefficients of variation for all measured lipid parameters were less than 5%.

The participants’ demographic characteristics, lifestyle characteristics, medical history, and medication history were collected, respectively. The diagnosis of hypertension was based on a self-reported history of hypertension, a mean blood pressure ≥ 140/90 mmHg on two measurements at physical examination, or a normal blood pressure that was being treated with antihypertensive medication [14 (link)]. The diagnosis of diabetes mellitus was based on a self-reported history of diagnosed diabetes mellitus or a FBG ≥ 7.0 mmol/L or normal blood glucose but on hypoglycemic treatment [15 (link)]. Blood was collected after fasting for more than 8 h for every participant. Biochemical parameters consist of high-sensitivity C-reactive protein (hs-CRP), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), TG, and low-density lipoprotein cholesterol (LDL-C) were analyzed using an automated analyzer (Hitachi, Tokyo, Japan). These parameters were monitored by professional quality control personnel to ensure accuracy.

Blood samples were kept at room temperature for 1 h, and centrifuged then at 1500 g for 10 min at 4 °C. The serum was separated and kept in 20 °C before analysis. The activity of AST, ALT, and ALP was measured using an automated analyzer (Hitachi, Japan) and available kits (Pars Azmoon, Iran) according to the manufacturer’s instructions.