According to our present data, we found that the prevalence of metabolic disorders is different between the Han and Kazakh populations. Compared with the Han population, the Kazakh population showed higher TC and LDL-C levels but lower FPG and TG levels, and similar results were also observed for the detection rate of metabolic disorders in the Han and Kazakh ethnic groups. Furthermore, these results were maintained after we divided these participants by sex.
The prevalence of metabolic syndrome has increased dramatically and has become a global public health focus. In this study, we tried to evaluate the glucose and lipid metabolism parameters in the Han and Kazakh ethnic groups, to find the metabolic characteristics in these groups. We observed differences in glucose and lipid metabolism between the Han and Kazakh ethnic groups, but the reason behind this phenomenon remains unknown. The Kazakh ethnic group in this county represents 35% of the total population. Their diet is rich in beef, mutton and dairy products, and they consume very little seafood, including shrimp, crab, and shellfish. Nang and milk tea are most frequently consumed for breakfast, and stir-fry or boiled meat are consumed for dinner. The high intake of high-protein, low-fibre foods has shifted the diet away from the traditional Chinese diet that is rich in low-protein food and characterised by a low intake of energy. The dietary energy intake is also slightly higher than the recommended standard of the Chinese dietary guidelines[11]. It is believed that this high-fat, high-protein and single type of food consumption in this area might be the primary reason for the high TC and high LDL-C detection rate relative to the national level[12, 13].
Similar to previous studies[14], we also observed sex differences in glucose and lipid metabolism among the Han and Kazakh populations. We found that most of the parameters and detection rate of metabolic disorders were all higher in men than in women. The sex differences in metabolic disorders between men and women may be related to dietary habits, lifestyle habits, hormones and other metabolic factors[15, 16]. This finding is an important clue for the management of sex-specific metabolic disease risk factors.
Among the detriments closely related to metabolic syndrome, cardiovascular and cerebrovascular diseases are the leading cause of death and disability, resulting in reduced quality of life and significant burdens on family and society[17]. Disorders of glucose and lipid metabolism eventually lead to metabolic syndrome and various cardiovascular and cerebrovascular diseases[18]. After lipid-lowering therapy, the risk of coronary heart disease and the incidence of cardiovascular and cerebrovascular disease decreases[19]. This study demonstrated that high FPG levels and high TG detection rates in the Han population in Balikun County were much higher than those in the Kazakh population, whereas the higher TC and LDL-C levels and high TC and LDL-C detection rates were significantly higher in the Kazakh population than in the Han population.
According to the 2016 Chinese guidelines for the prevention and control of dyslipidaemia in adults, LDL-C ≥ 4.9 mmol/L and 1.8 mmol/L (70 mg/dL) ≤ LDL-C ≤ 4.9 mmol/L (190 mg/L) in diabetic patients aged 40 years or over are both risk factors for ASCVD. For Kazakh people, LDL-C ≥ 4.9 mmol/L is the main ASCVD risk factor, and this value is much higher than in the Han population. Regarding 1.8 mmol/L (70 mg/dL) ≤ LDL-C ≤ 4.9 mmol/L (190 mg/L) in diabetic patients aged 40 years and over, the risk in the Han population was much higher than that in the Kazakh population. Analysing sex differences based on these two cut-off reference values, we observed similar patterns in both ethnic groups. Thus, ethnic differences with respect to ASCVD risk exist among the Han and Kazakh ethnic groups in Balikun County in Xinjiang, suggesting that future health education in this region should address the unique risks of different ethnic groups with respect to diabetes, coronary heart disease and ASCVD. Diabetes prevention and hypoglycaemia treatment are more important in the Han population, whereas the prevention of hyperlipidaemia and lipid-lowering treatment are more important in the Kazakh population.
The limitations of this study also deserve attention. First, due to limited manpower, material and time, we were unable to investigate the diet of the Han and Kazakh populations in this area during the study period. Second, the present data were obtained using a cluster sampling method and did not include physical examination data from the entire population. Therefore, bias may exist in the results. Future studies should focus on improvements in investigation methods and should collect more comprehensive data to clearly reflect glucose and lipid metabolism disorders in this area in a more scientific manner. Third, we evaluated ASCVD risk only based on the status of glucose and lipid metabolism, and ASCVD prevalence in the real world was not recorded in this study.
In conclusion, our study examined the incidence of glucose and lipid metabolic disorders in the Han and Kazakh ethnic groups in Balikun County and observed the effects of differences in ethnicity, sex and region on glucose and lipid metabolism disorders and ASCVD risk. We found that the prevalence of metabolic disorders in the Han and Kazakh people in Balikun County were different with regard to sex, ethnicity and metabolite component heterogeneity. The risk of diabetes and increased TGs was higher in Han individuals, while the risk of increased LDL-C was higher in Kazakh individuals. This study provides a scientific basis and new idea for local ethnic groups for preventing and controlling cardiovascular and cerebrovascular diseases caused by metabolic disorders.