The Reference Interval Values of Biochemical Parameters in Iranian Kurdish Adults: Results from Non-communicable Diseases of Ravansar Cohort

This study aimed to establish age- and sex-specific biochemical parameters Reference intervals (RIs) in a healthy adult Kurdish population. The biochemical markers were investigated in 2850 individuals (1365 female and 1485 male) from Ravansar Non-Communicable Disease (RaNCD) cohort study. The biochemical markers were measured using an enzymatic assay. The non-parametric method was used to calculate RIs for all partitions. The liver enzymes and TG, HDL-C, and creatinine levels were gender- and age-dependent. The RIs of these parameters in the Iranian population are dramatically lower compared to other populations. Smokers and overweight subjects had higher liver enzymes and lipid profile levels. Similar results were obtained in post-menopause females. Individuals in the high physical activity group had a lower activity of ALP and GGT and a higher ALT and AST, also, lower lipid profile (TC, TG, and LDL) and FBS, and higher HDL levels. Our study suggests that chemical biomarkers are influenced by gender and age, and factors such as BMI, smoking status, physical activity, and menopause status must be considered in laboratory analysis. Additionally, the results indicated that reference values of commercial kits routinely used, especially liver enzymes, could not be appropriate for the Iranian Kurdish population.