Albuminuria:Associated Risk Factors And Relationship With Cardiovascular Disease

Objective 1. Aims to investigate the prevalence and associated risk factors of albuminuria for subjects involved in epidemiological investigation of diabetes.2. to anlyze the association between micro albuminuria and metabolic syndrome and its components.3. to determine the relationship between albuminuria and low estimated glomerular filtration rate (eGFR) and whether risk factors differ for them.4. to further explore relationship of albuminuria, metabolic syndrome and decreased eGFR with cardiovascular disease (CVD).Methods A nationally representative sample from a diabetes study in China from 2007 to 2008 were enrolled in our study.1. Subjects was categorized by different levels of urinary albumin-to-creatinine ratio (ACR),0-10 mg/g (n=17,564),10-20 mg/g (n=9,423),20-30 mg/g (n=3,765), 30-300 mg/g (n=7,451) (Excluding ACR>300 mg/g). The prevalence of albuminuria was compared by using a single urinary ACR cutoff point (ACR>30 mg/g) and by sex-specific ACR cutoff points (>14 mg/g for male,>20 mg/g for female). Factors associated with the presence of albuminuria and the relationship between albuminuria and CVD were analyzed by logistic regression.2. We defined microalbuminuria as a urinary albumin-to-creatinine ratio of 30 to 300mg/g. The metabolic syndrome was defined based on the Chinese Diabetes Society(CDS) and International Diabetes Federation(IDF)criteria. The relationship between MS and MAU was examined using multiple linear and logistical regression analysis. CVD risk for both MS and MAU were analyzed.3. A total of 8,890 subjects with serum creatinine were analyzed. Reduced eGFR was defined as an eGFR<60 ml/min/1.73 m2, and albuminuria was defined as a urine albumin/creatinine ratio≥30 mg/g. Risk factors for albuminuria and decreased eGFR were analyzed respectively, and relationship with CVD was further explored using logistical regression analysis.Results1. Prevalence of albuminuria as measured by a single ACR cutpoint was significantly lower for men compared with women (13.9% vs 19.1% in NGT group; 20.8% vs 26.8% in IGR group, P<0.01). Prevalence of albuminuria as measured by sex-specific ACR cutpoints was higher for men than women (31.4% vs 29.6% in NGT group; 42.2% vs 39.3% in IGR group, P<0.01), but the absolute difference is small. The independent risk factors for presence of albuminuria were aging (age>60y), women, hypertension, hyperglycemia (IGT、IFG/IGT and newly onset diabetes), overweight or obesity, dyslipidemia, insulin resistance (IR), and metabolic syndrome, P<0.05. Albuminuria did not has a linear or statistically significant relationship with CVD after adjusting conventional risk facors for CVD, including sex, age, waist, hyperglycemia, hypertension, dyslipidemia and insulin resistance (P>0.05).2. Among a total number of 39,006 participants included, the prevalence of MS was 22.8% by CDS criteria,25.0% by IDF criteria. By CDS criteria, the prevalence of MAU in the MS (n=8,898) group was 25.5%(n=4,324) for men,33.8%(n=4,574) for women. By IDF criteria, the prevalence of MAU in the MS (n=9,756) group was 24.9% (n=3,448) for men,31.1%(n=6,308) for women. Of the MS components, MAU was significantly associated with impaired fasting plasma glucose, hypertension and high triglyceride(TG), P<0.001. After adjusting sex, age, BMI, smoking, and alcohol intake, the odds ratio (OR) of MAU for individuals with MS was 1.58 (95%CI 1.47-1.70) by CDS criteria, and 1.41(95%CI 1.31-1.52) by IDF criteria, P<0.001. The mainly associated components of MS for CVD risk were TG (OR 1.52, by IDF criteria; OR 1.48, by CDS criteria), HBP (OR 1.50, by IDF criteria; OR 1.48, by CDS criteria), and central obesity (OR 1.28, by IDF criteria; OR 1.30, by CDS criteria), p<0.001. Both of MS and MAU were significantly associated with CVD risk, P<0.05. The adjusted OR of CVD risk was 1.67 by CDS criteria, and 1.58 by IDF criteria for patients with both MS and MAU, P<0.001.3. Relationship of albuminuria and reduced renal function:for patients with eGFR <60 ml/min/1.73 m2 (n=123), albuminuria proportion was 37.4%; for patients with albuminuria (n=1,731), prevalence of eGFR< 60 ml/min/1.73 m2 is only 2.7%. Among patients with diabetes(n=1,055), dyslipidemia(n=5,117), hypertension(n=3,172), and metabolic syndrome (MS, n=2,259), the ratio of eGFR< 60 ml/min/1.73 m2 was 1.8%, 1.5%,2.0% and 2.3% respectively (P>0.05), the ratio of albuminuria 34.9%,23.1%, 30.4% and 32.1% respectively (P<0.001), and the combination ratio of eGFR< 60 ml/min/1.73 m2 and albuminuria very low,1.1%.0.7%.1.1% and 1.1% respectively (P<0.001). Aging (every 10 y increase, OR 1.3,95%CI 1.2-1.5), albuminuria (OR 2.1, 95%CI 1.4-3.2), and hyperuricemia (OR 3.7,95%CI 2.4-5.7) were mainly independent predictors for reduced renal function, P<0.001. Aging (every 10 y increase, OR 1.1, 95%CI 1.1-1.2, P<0.001), female (OR 1.7,95%CI 1.5-1.9, P<0.001), central obesity (OR 1.4,95%CI 1.2-1.6, P<0.001), diabetes (OR 1.8,95%CI 1.5-2.0, P<0.001), hypertension (OR 2.0,95%CI 1.8-2.3, P<0.001), dyslipidemia (OR 1.3,95%CI 1.1-1.4, P<0.001), reduced renal function (OR 2.2,95%CI 1.5-3.2, P<0.001) and history of cardiovascular disease (CVD) (OR 1.3,95%CI 1.0-1.8, P<0.05) were all independently associated with albuminuria. After adjusting risk factos such as sex, age, smoking, alcohol intake and hyperuricemia, diabetes, hypertension, dyslipidemia, and central obesity were all important risk factors for CVD history. Reduced renal function or albuminuria were not independent risk factor for CVD history, P>0.05.Conclusion1. The prevalence of albuminuria (ACR>30 mg/g)was 19.5% for Chinese population involved in epidemiological investigation of diabetes. And the prevalence of albuminuria was increased with the accumulating components of MS.2. Aging, women, hypertension, hyperglycemia, dyslipidemia, IR, obesity and metabolic syndrome were all independent risk factors for albuminuria. The prevalence and associated risk factors of low eGFR and albuminuria among the Chinese existed difference.3. Both of MS and MAU were independent risk factors for presence of CVD history. MS was more powerful than MAU in predicting risk of CVD history.