Prevalence And Influencing Factors Of Dyslipidemia For A Rural Population In Henan

ObjectiveDyslipidemia is the presence of raised or abnormal levels of lipids and/or lipoproteins in the blood,which refers primarily higher blood total cholesterol(TC) and triglyceride(TG) levels and lower blood high density lipoprotein cholesterol (HDL-C) levels.The Framingham Heart Study by following up 5209 residents for 30 years of risk factors on coronary heart disease(CHD) since 1948 indicated that there was a linear relationship between the risk of occurrence of clinical CHD and cholesterol levels.Over the past 20 years,the trends and changes of lipid levels in Chinese have been followed closely by the researchers.Since 1980's,many large-scale epidemiological studies of cardiovascular disease included the investigation and long-term monitoring on lipid levels.Dyslipidemia is a common disease which has great effect on health,its incidence rate is rather high,whereas the control rate is very low.It occurs with no obvious symptoms and often results in coronary heart disease,stroke and other serious vascular diseases.As some western developed countries began national cholesterol education program earlier,the prevalence of dyslipidemia declined.But with rapid economic development,elevated standard of living,changing lifestyle and aging,the prevalence rate of dyslipidemia is increasing in many developing countries.Recent studies have shown the prevalence of dyslipidemia in Chinese adults was 18.6%,this indicates that 200 million people have dyslipidemia in 2006, which means one person occurs dyslipidemia every five people.The present study was designed to provide current and reliable data on the prevalence,distribution characteristics and influencing factors of dyslipidemia in Henan rural residents.We also want to analyze the relationship between dyslipidemia and related chronic diseases such as hypertension,type 2 diabetes mellitus(T2DM) and metabolic syndrome(MS),to compare central and overall obesity measurements as correlates of dyslipidemia and furtherly to determine which single measurement is more powerful for predicting dyslipidemia.Subjects and methodsParticipants aged 18 years old and over were selected randomly by cluster sampling.Data was collected by questionnaire interview(demographic characteristics,medical history,and behavior risk factors),anthropometric measurements[height,weight,waist circumference(WC),and blood pressure],and laboratory measurements fasting plasma glucose,TC,TG,and HDL-C) in Xin'an County,Luoyang City of Henan Province from July to August in 2007 and 2008. 20194 participants(7943 males and 12251 females) completed all the surveys. Cross-sectional and case-control study designs were used to analyze the prevalence, risk factors,and the relationship between dyslipidemia and hypertension,T2DM, MS.Receiver operating characteristric curve(ROC) was used to compare central and overall obesity measurements as correlates for identifying dyslipidemia in different genders.Results1.Prevalence of dyslipidemiaThe crude prevalence rate of dyslipidemia was 43.93%,and the age-adjusted rate was 41.17%by the population data of 2000 in China.The prevalence rate of dyslipidemia in males was 49.20%,and 40.52%in females.The prevalence rate of males was higher than that of females.There were significant differences for the prevalences on dyslipidemia among different age groups in males and females.The prevalence rates of dyslipidemia increased significantly with age in females(P＜0.05) but not in males.The-prevalence of dyslipidemia was higher in men with high education level and in women with low education level.There were no statistically significant differences for the prevalence rates of dyslipidemia among different marital status and income levels.2.Influencing factors of dyslipidemiaAfter adjusted for age,education levels,marital status,average monthly individual income and other factors,logistic regression analysis shows that smoking (OR=1.30,95%CI:1.15-1.46),family history of hyperlipidemia(OR=1.21,95%CI: 1.04-1.41),body mass index(OR=1.63,95%CI:1.47-1.81),waist circumference(OR=1.71,95%CI:1.44-2.03),fasting plasma glucose(OR=1.19, 95.%CI:1.06-1.34) were significantly positively associated with dyslipidemia, whereas,alcohol drinking(OR=0.84,95%CI:0.74-0.95),physical activity(OR=0.89, 95%CI:0.83-0.95) were negatively associated with the development of dyslipidemia in males.For females,body mass index(OR=1.26,95%CI:1.17-1.36),waist circumference(OR=1.76,95%CI:1.56-1.98),fasting plasma glucose(OR=1.40, 95%CI:1.28-1.54) were significantly positively associated with dyslipidemia.3.Dyslipidemia and related chronic diseasesWith the TC,TG,and low density lipoprotein cholesterol levels increasing and HDL-C decreasing,the prevalence rates of hypertension,type 2 diabetes and metabolic syndrome increased.After adjusted for gender,age,marital status,income and educational levels,Logistic regression analysis revealed that compared to the control group,odds ratios for individuals who have dyslipidemia suffering from hypertension,T2DM and MS were 1.48(95%CI:1.39-1.58),2.25(95%CI: 2.02-2.51) and 4.83(95%CI:4.50-5.17) respectively.4.The identifyting abilities of different obesity measurements for dyslipidemiaROC analysis revealed significant differences between the areas under the ROC curves(AUCs) for WC(0.67,95%CI:0.66-0.68) and body mass index(BMI)(0.66, 95%CI:0.65-0.67) and waist to height ratio(WHtR)(0.67,95%CI:0.66-0.68) and BMI for identifying dyslipidemia(all P＜0.05) in males and WC(0.65,95%CI: 0.65-0.66) and BMI(0.63,95%CI:0.62-0.64) and WHtR(0.65,95%CI:0.64-0.66) and BMI in females.There were no statistically significant difference between the AUCs for WC and WHtR for predicting dyslipidemia in mals and females.Conclusions1.The prevalence of dyslipidemia is very high in a rural population of Henan.It's urgent to prevent dyslipidemia effectively in this population.2.Multivariate analysis shows that obesity and higher fasting blood glucose level play an extremely important role for the prevention and treatment of dyslipidemia.3.Dyslipidemia is positively associated to hypertension,T2DM and MS,the prevention and control of dyslipidemia may reduce the incidence and prevalence of other related chronic diseases.4.Central rather than overall obesity is related more closely to dyslipidemia,and both WC and WHtR are equally able to identify dyslipidemia.