The relationship between dyslipidemia and inflammation among adults in east coast China: A cross-sectional study

Abstract

Objective: Dyslipidemia is one of the major public health problems in China. It is characterized by multisystem dysregulation and inflammation, and oxidant/antioxidant balance has been suggested as an important factor for its initiation and progression. The objective of this study was to determine the relationship between prevalence of dyslipidemia and measured changes in the levels of proinflammatory cytokines (IL-6, TNF-a, and MCP-1), thiobarbituric acid-reactant substances (TBARS), and serum total antioxidant capacity (TAC) in serum samples.

Study design: A cross-sectional survey with a purposive sampling of 2,631 enrolled participants (age 18-85 years) was performed using the adult population of long-term residents of the municipality of east coast China in Fujian province between the years 2017 and 2019. Information on general health status, dyslipidemia prevalence, and selected mediators of inflammation was collected through a two-stage probability sampling design according to socioeconomic level, sex, and age.

Methods: The lipid profile was conducted by measuring the levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) with an autoanalyzer. Dyslipidemia was defined according to National Cholesterol Education Program Adult Treatment Panel III diagnostic criteria, and patients with it were identified by means of a computerized database. Serum parameters including IL-6/TNF-a/MCP-1, TBARS, and TAC were measured in three consecutive years. Familial history, education level, risk factors, etc. were determined. The association between dyslipidemia and serum parameters was explored using multivariable logistic regression models. Sociodemographic, age, and risk factors were also investigated among all participants.

Results: The mean prevalence of various dyslipidemia in the population at baseline (2017) was as follows: dyslipidemias, 28.50%; hypercholesterolemia, 26.33%; high LDL-C, 26.10%; low HDL-C, 24.44%; and hypertriglyceridemia, 27.77%. A significant effect of aging was found among all male and female participants. The mean levels of serum Il-6/TNF-a/MCP-1 were significantly higher in all the types of dyslipidemia among male participants. Female participants with all types of dyslipidemia but low HDL-C showed an elevation of IL-6 and MCP-1 levels, and those with dyslipidemias and hypercholesterolemia presented higher levels of TNF-a compared to the normal participants. The oxidative stress marker TBARS increased among all types of dyslipidemia except hypertriglyceridemia. All participants with different types of dyslipidemia had a lower total antioxidant capacity. Correlation analysis showed that cytokines and TBARS were positively associated with age, obesity, and diabetes mellitus, but not sex, sedentary leisure lifestyle, hypertension, and CVD/CHD history. The activity of TAC was negatively associated with the above parameters.

Conclusions: The correlation between the prevalence of dyslipidemia and the modification of inflammation status was statistically significant. The levels of proinflammatory cytokines, oxidative stress, and antioxidant capacity in serum may reflect the severity of the lipid abnormalities. These promising results further warrant a thorough medical screening in enhanced anti-inflammatory and reduced oxidative stress to better diagnose and comprehensively treat dyslipidemia at an early stage.

Keywords: IL-6; MCP-1; TAC; TBARS; TNF-a; dyslipidemia.

Figure 1

Male age-specific prevalence of high total (non-HDL) cholesterol (A), high low-density lipoprotein cholesterol (B), low high-density lipoprotein (C), high triglyceride (D), and dyslipidemias (E) among urban adults in East Coast, Fujian, China between 2017 and 2019. Logistic regression analysis indicated: * aging trend within each lipid abnormality (A) p < 0.005; (B) p < 0.001; (C) p < 0.001; (D) p = 0.003; (E) p < 0.001, and ^ for time trend within the age group (B) p < 0.001.

Figure 2

Female age-specific prevalence of high total (non-HDL) cholesterol (A), high low-density lipoprotein cholesterol (B), low high-density lipoprotein (C), high triglyceride (D), and dyslipidemias (E) among urban adults in East Coast, Fujian, China between 2017 and 2019. Logistic regression analysis indicated: * aging trend within each lipid abnormality (A) p < 0.01; (B) p < 0.001; (C) p < 0.001; (D) p = 0.002; (E) p < 0.001, and ^ for time trend within the age group (B) p < 0.001.

Figure 3

Serum levels of proinflammatory cytokines, oxidative stress, and antioxidant capacity within different lipid abnormalities among male adults. IL-6 (A), TNF-β (B), MCP-1 (C), TBARS (D), and TAC (E). Logistic regression analysis indicated: *p < 0.05, **p < 0.01 overall difference vs. the level of lipid normal group.

Figure 4

Serum levels of proinflammatory cytokines, oxidative stress, and antioxidant capacity within different lipid abnormalities among female adults. IL-6 (A), TNF-β (B), MCP-1 (C), TBARS (D), and TAC (E). Logistic regression analysis indicated: *p < 0.05, **p < 0.01, overall difference vs. the level of lipid normal group.