Epidemic characteristics of gout and primary hyperuricemia in Shandong coastal area: A randomized stratified cluster sampling survey / 中国组织工程研究

ABSTRACT

BACKGROUND: Recent studies have found that hyperuricemia and gout are closely correlated with the occurrence and development of diabetes, coronary heart disease, hypertension and cerebrovascular diseases. It is of significance to investigate their prevalence so as to find way of early interventions.OBJECTIVE: To determine the prevalence and risk factors of gout and hyperuricemia among residents above 20 years old in Shandong coastal area.DESIGN: A randomized, stratified cluster sampling survey.SETTING: Department of Endocrinology, Affiliated Hospital of Qingdao University Medical College.PARTICIPANTS: A random, stratified cluster sampling was conducted in Shandong coastal area including Qingdao,Yantai, Weihai, Rizhao and Dongying. Residents lived in these areas for 5 years or more, aged between 20 to 80 years, were selected, and they were surveyed by family as a unit.METHODS: A randomized, stratified cluster sampling survey was conducted. The prevalence of gout and hyperuricemia were investigated among about 5 000 residents in Qingdao, Yantai, Weihai, Rizhao and Dongying. The serum uric acid, lipids, glucose and creatinine were detected with Sysmex chemix-180 total automatic biochemical analyzer. Those with uric acid higher than reference level were reexamined by collecting fasting blood sample on the third day. The comparison between rates was taken with the Chi-square test, means between two groups with the t test, means between multiple groups with analysis of variance, correlation between dependent and independent variables with logistic regression analysis.MATN OUTCOME MEASURES: Prevalance of hyperuricemia; Level of serum uric acid; Prevalence of gout in patients with hyperuricemia; Influencing factor of hyperuricemia.RESULTS: This investigation planned to include 5 500 subjects while in fact 5 003 subjects were investigated and the response rate was 91%, in which males were 2 395 (47.87%) and females were 2 608 (52.13%). ① The prevalence of hyperuricemia was 13.19% with standardized rate of 13.27% according to the Shandong population in 2000; The pevalence was higher in males than in females (18.32%, 8.56%, x2=108.52, P＜ 0.01). The risk in males was 2.5 times higher than that in females (OR =2.5). The prevalence of gout was 1.14% with standardized rate of 1.10%; and the prevalence in males was higher than that in females (1.94%, 0.42%, x2=30.38, P ＜ 0.01). The risk in males was 5.3 times higher than that in females (OR =5.3). ②The average value of serum uric acid in normal males was higher than in normal females [(343.40±84.54), (258.90±70.90) μmol/L, t =48.03, P ＜ 0.01]. It was obviously higher in male patients with hyperuricemia than in female ones [(469.43±48.08), (399.73±104.91) μmol/L, t =11.70, P ＜ 0.01]. It was higher in male patients with gout than in female ones [(502.44±106.76), (403.48±52.72) μmol/L, t =2.07, P ＜ 0.05]. ③The prevalence of gout in patients with hyperuricemia was 8.34%. ④ The prevalence of hyperuricemia and gout were climbing up with age after 40 years old in females and those elder than 70 years old were of high risk; while in males,the prevalence of hyperuricemia and gout increased with age before 60 years old and those aged 50-59 years were of high risk, yet after 60 years, it climbed up with age again. Nevertheless, the mean ages of hyperuricemia and gout in females were older than male. The average episode ages of hyperuricemia and gout in females were later than in males respectively by 7.5 and 8.5 years. ⑤ Non-conditional Logistic regression analysis showed that drinking frequency,drinking quantity, the quantity and frequency of seashell intake, BUN, Cr, TG, TC, BMI and WHR were the independent risk factors of male patients with hyperuricemia [OR =1.016-30.217, 95%C/ (1.010-1.023)-(9.955-214.869)]; while HDL-C and heavy physical labour were the protective factors (OR =0.492, 95%C/ 0.339-0.713; OR =0.755, 95% CI 0.575-0.991).As for females, age, hypertension, the quantity of seashell food intake, BUN, Cr, TG, WHR and light physical labour were the independent risk factors of hyperuricemia [OR =1.022-27.34, 95%CI (1.006-1.040)-(9.955-214.869)]. Similarly, HDL-C was a protective factor (OR =0.428, 95%CI0.223-0.820).CONCLUSION: ① The prevalence of hyperuricemia and gout are different between genders ② The risk factors of hyperuricemia and gout among residents in Shandong coastal area include the high intake of marine products such as seashell foods, less physical activity, abdominal obesity and kidney insufficiency, as well as the existence of metabolic syndrome. Drinking is also involved in the increased prevalence in males, and age in females. ③ Higher risk for hyperuricemia and gout are noticed in all age groups in males, whereas in females after 50 years old.