Influence of ethnicity on population reference values for biochemical markers

Abstract

Reference intervals (RIs) for biochemical and hematological markers determined using healthy adult and/or pediatric populations are vital for clinical interpretation of laboratory test results. Most clinical laboratories commonly use age- and sex-specific RIs, but the effect of ethnicity as a covariate is often overlooked. Ethnic differences in serum biomarker concentrations can occur as a result of genetic and environmental factors, while the degree to which each factor influences serum levels depends on the specific biomarker. Numerous studies have investigated ethnic differences in routine chemistry, fertility, endocrine, cancer, and hematological markers, as well as in vitamins and carotenoids, in children, adolescents and adults. In the present review, we summarize and discuss ethnic-specific differences observed for these laboratory markers and their potential impact on the clinical interpretation of laboratory test results. We categorized the available data into seven major ethnic groups (i.e. Black, Caucasian, East Asian, Hispanic, South Asian, South East Asian, and West Asian) for ease of comparison. While certain biomarkers could not be compared between ethnic groups because of insufficient information or contradictory results between studies, significant differences between ethnic groups were reported by one or more studies for most of the biomarkers included in this review. The clinical significance of these differences and the potential need for ethnic-specific RIs for certain biochemical markers are also discussed.

Reference intervals established using indirect method for serum ferritin assayed on Abbott Architect i2000SR analyzer in Chinese adults

“…Even in whole Chinese adult females, the upper limits of RIs for SF are also elevated. Similar findings were observed in the Canadian Health Measures Survey by Khosrow et al As mentioned above, these findings might be related to considerable variation in SF levels in ethnic origin . In fact, in multi‐ethnic population studies in the USA, Adams et al had proved that elevated SF levels are more frequent in Afro‐Caribbean and Asian subjects than in whites or Hispanics.…”

“…Interestingly, our study demon- by Khosrow et al 38 As mentioned above, these findings might be related to considerable variation in SF levels in ethnic origin. 3,22,35 In fact, in multi-ethnic population studies in the USA, Adams et al 39 had proved that elevated SF levels are more frequent in Afro-Caribbean and Asian subjects than in whites or Hispanics. In a previous Chinese study on Cobas® 6000 system E601 (Roche) analyzer, Li et al 40 also found that Chinese adult males had higher RIs for SF.…”

“…This makes it difficult for physicians to interpret the measurement results. In addition, studies have addressed there are significant ethnic‐specific differences in SF levels . Hence, it is necessary to establish their own RIs for use in clinical laboratories with their population and analytical methods…”

“…In addition, studies have addressed there are significant ethnic-specific differences in SF levels. 3,22 Hence, it is necessary to establish their own RIs for use in clinical laboratories with their population and analytical methods. 18 According to international recommendations by the International…”

Age- and Sex-Specific Reference Intervals for Myocardial Enzyme Activity in Healthy Chinese Han Population Aged 1∼<18 years

“…Research studies find [2][3][4][5] RIs are with variety of factors involved such as race, region, ethnicity, diet, and so on. For example, Wu et al [6] found that lower limit of the platelet interval in Chinese Han adults was slightly lower than that of the peer group in the United States [7] and Malaysia [8], and RIs of white blood cell count and neutrophil count were lower than those of the homologous US population [7] while higher than those of the Africans [9]; Oliver's research [10] showed that RIs of certain biochemical indicators of the aged living in Asmara, Eritrea, were higher than those of Caucasians and lower than those of South Africans.…”