Trends In The Epidemiology And Risk Factors For Chronic Kidney Disease And Its Systematic Review

Chronic kidney disease(CKD) is becoming a major public health issue worldwide with an increasing incidence and prevalence year by year. By December 31, 2012, there are a total of 244,121 patients under maintenance hemodialysis and 37,942 cases under maintenance peritoneal dialysis in our country. It is estimated that the number of the dialysis population in China will increase at rate of 20–30% per year. Meantime, End-stage renal disease(ESRD) increased medical costs and risk of mortality, was an important contributor to the health and social burdens, caused a huge challenge to medical and health undertakings. However, ESRD just a tip of the iceberg, only accounted for about 1% ESRD patients in all stages chronic kidney disease. So, more relatively early stage chronic kidney disease patients hidden behind growing ESRD. Since the National Kidney Foundation released K/DOQI(Kidney diseases, Outcome Quality Initiative) guidelines at 2003, CKD epidemiological studies carried out rapidly all over the world, European and American developed countries and some developing countries in Africa and South America have published epidemiological data of CKD in their region. Compared with epidemiologic study on CKD abroad, the epidemiological investigation of CKD started relatively late in our country, Only Beijing, Guangzhou, Shanghai, Zhengzhou and other cities published single center data of CKD between 2008-2009. In 2002, the first multi-center epidemiology survey on CKD were carried out in China, 47204 adult respondents from13 provinces and cities across the country participated in the survey, the results showed that the total prevalence of chronic kidney disease is 10.8%. and China has nearly 119.5 million patients with chronic kidney disease.With the advancement of CKD epidemiological research, the related risk factors for occurrence and progression of CKD were understood gradually. In addition to gender, age and race, metabolic diseases, such as obesity, hypertension, diabetes, lipid metabolic disorders have attracted more and more attention. Especially, the relationship between metabolic syndrome(MS) and its components and CKD were confirmed by more and more researches.The Epidemiology investigation on chronic kidney disease has passed more than 10 years since the National Kidney Foundation released K/DOQI guidelines at 2003. The prevalence of chronic kidney disease have changed over time on the basis of abroad data. According to data from the National Health and Nutrition Examination Survey(NHANES), the CKD prevalence in the USA was increased from 10.0% on NHANES 1988–1994 to 13.1% on NHANES 1999–2004. In a recent trend analysis, the overall CKD prevalence among the Japanese male population was increased from 13.8% in 1974 to 22.1% in 2002. Another trend analysis from Korean, According to Chin et al, the CKD prevalence in the Korean adult population was decreased from 8.8% in 2005 to 7.2% in 2007. However, the epidemiologic study on CKD in China only still stay on the cross-sectional investigation, still lack of follow-up cohort study.In 2007, we had carried out cross-sectional epidemiological investigation on chronic kidney disease among adult population in zhengzhou city, obtaining the data of CKD, albuminuria, hematuria and reduced glomerular filtration rate(e GFR) prevalence. The results confirmed that gender, age, race, obesity, hypertension, diabetes and hyperuricemia were risk factors for CKD in Zhengzhou adults. At the same time, we also analyzed the relationship between MS and CKD from every component to the number of component. Henan province located in the central plains, has achieved rapid economic and social development over the past 5 years. The residents’ lifestyle and diet structure have been changed a lot in zhengzhou city. And the epidemiology of metabolic diseases such as hypertension, diabetes, obesity, also taken place great changes. Whether the prevalence and distribution characteristics of chronic kidney disease have changed? And whether the prevalence of albuminuria, hematuria, reduced glomerular filtration rate also changed? Meanwhile, it is not clear whether the risk factors for CKD also changed with them. On the other hand, to some extent, the report published by Zhang Luxia et al. represents the data of epidemiology on CKD in China. But these factors, including vast territory, large population, the imbalance of the development of economic and health, may have an effect on the results. If data from single-center studies are comprehensively analyzed and give systematic reviews, the whole panorama of CKD will be revealed, which would be significantly helpful for the prevention and control of CKD in our country.Based on this background, this research explored the trends in epidemiology and risk factors for chronic kidney disease and its systematic review from longitudinal follow-up queue and meta analysis on cross-sectional survey. On the one hand, we initiated this cohort study after 5 years on the basis of cross-sectional epidemiological survey in 2007. Through comparison and analysis to reveal the trends in the epidemiology for chronic kidney disease and its related risk factors in adult population in zhengzhou city. Especially, focuses more attention on the role of MS on the occurrence and progression of CKD. On the other hand, Published literatures about the epidemiological investigation of CKD in our country were reviewed, and related data were summarized by system analysis so as to reveal the epidemiological features of CKD of our country. Thus, the study will fill the blank of the cohort of CKD in our country and enhance the representativity of data from cross-sectional survey. it will be important for improving the level of prevention and control of CKD in ChinaPartⅠ Trends in the epidemiology for chronic kidney disease among adult population in Zhengzhou cityMethodsCombined with Epidemiology investigation on chronic kidney disease among adults in urban communities of Zhengzhou city in 2007, we developed special follow-up questionnaire for gathering information of population included in 2007 study, including questionnaire, physical examination and kidney damage detection and related risk factors, comparative analysis the trends of prevalence and distribution characteristics of chronic kidney disease among adult population in zhengzhou city from 2007 to 2012.Results1. Trends in study population and clinical characteristics 1668 subjects were accepted to investigate, and Eligible data of 1593 subjects were enrolled in 2007. 166 cases lost to follow-up in 2012, non-investigation rate was 10.42%, and a total of 1427 adults was included in the cohort study. Of them 556 are males(38.96%) and 871 are females(61.04%) with the average age of 58.93 ±14.4 years. The prevalence of hypertension and diabetes was significantly higher than that in 2007(31.67% vs 19.40%, P<0.001 and10.65% vs 6.34%, P<0.001).2. Trends in the prevalence of albuminuria from 2007 to 2012 The prevalence of albuminuria was 10.02%, which increased significantly compared to 2007(10.02% vs 5.90%, P < 0.001). Both in male and female population, the prevalence of albuminuria were higher than that in 2007(8.63% vs 4.40%, P=0.003 and 10.91% vs 6.90%, P=0.003, respectively), but the sex differences in 2007 has disappeared(P=0.163).3. Trends in the prevalence of hematuria from 2007 to 2012. From 2007 to 2012, the prevalence of hematuria decreased from 6.59% to 5.68%. Especially, women had relatively obvious decreased in prevalence of hematuria, from 7.71% in 2007 to 6.08% in 2012(P=0.175). Meanwhile, the difference of hematuria prevalence between women and men had no statistical(P=0.404).4. Trends in the prevalence of reduced e GFR from 2007 to 2012. In the follow-up, the prevalence of reduced e GFR was 3.71%, which was increased significantly compared to 2007(3.71% VS 1.44%, P<0.001). The reduced e GFR prevalence increased from 2.28% in 2007 to 5.94% in 2012 in male population and from 0.86% in 2007 to 2.30% in 2012 in female population(P=0.001 and P=0.013). And the sex difference was still significant(5.94% VS 2.30%, P<0.001).5. Trends in the prevalence of CKD from 2007 to 2012. In 2012, The crude prevalence of CKD was 15.98% and standardized rate was 15.78%, which was increased significantly in whole population(15.98% VS 11.86%, P=0.001), also increased significantly both in male(14.75% vs 9.71%,P=0.007) and female population(16.76% vs 13.38%, P=0.045) compared to 2007. Compared with 2007 data, the CKD2 stage and CKD3 stage prevalence increased significantly(4.41% VS 2.82%, P=0.019 and 3.01% VS 1.26%, P=0.001).6. Change in the distribution characteristics of CKD. The proportion of single hematuria in the whole CKD decreased from 42.33% in 2007 to 26.32% in 2012.. While, single albuminuria or e GFR percentage increased compared 2007. Albuminuria / reduced e GFR dominate in patients with two kidney damage forms, from 2.12% in 2007 to10.53% in this follow up.7. Trends in the awareness rate of CKD from 2007 to 2012. The awareness rate of CKD was 9.52% in 2007, which rised to 66.67%. in this follow-up.Conclusions1. This is the first cohort study on chronic kidney disease in China, which confirmed the epidemiology of CKD among adult population in Zhengzhou have trended.2. The prevalence of CKD, albuminuria and reduced e GFR rised compared 2007. while, the hematuria prevalence trended down over the past 5 years.3. The distribution characteristics of CKD with only single hematuria was changing, Albuminuria or/and reduced e GFR accounted for a growing percentage of CKD.4. The awareness rate of CKD in this crowd increased considerably.PartⅡ Trends in the risk factors for chronic kidney disease among adult population in Zhengzhou cityMethodsCombined with Epidemiology investigation on chronic kidney disease among adults in urban communities of Zhengzhou city in 2007, we developed special follow-up questionnaire for gathering information of population included in 2007 study, including questionnaire, physical examination and kidney damage detection and related risk factors. To assess the trends of related risk factors for CKD, especially changes in the relationship between MS and CKD from 2007 to 2012.Results1. Change in baseline information 1668 subjects were accepted to investigate, and Eligible data of 1593 subjects were enrolled in 2007. The prevalence of CKD, albuminuria, hematuria, reduced glomerular filtration rate was 11.86%, 5.90%,6.59% and 1.44%, respectively. 166 cases lost to follow-up in 2012, non-investigation rate was 10.42%, and a total of 1427 adults was included in the cohort study. The CKD, albuminuria and reduced glomerular filtration rate rised up to 15.98%, 10.02% and 3.71%, respectively.2. Trends in the risk factors for CKD. In first survey in 2007, we found gender(female), age, obesity, hypertension, diabetes and hyperuricemia were risk factors for CKD in zhengzhou adults. While, in this follow-up, female was no longer the risk of CKD [OR = 1.137(0.886 ~ 1.457)], but, age, hypertension and diabetes significantly increased the risk of CKD with odds ratio 2.340 [95% CI(1.479 ~ 3.961)], 2.552 [95% CI(1.603 ~ 4.182)] and 3.041 [95% CI(1.761 ~ 4.520)].3. Trends in the relationship between MS or its component and CKD. In 2012 follow-up, the prevalence of MS increased to 27.68% from 16.50%. Population with MS also had much higher albuminuria and reduced glomerular filtration rate prevalence. The risk of albuminuria and reduced glomerular filtration rate increased with MS from an odds ratio(OR) of 1.832 and 1.944 in 2007 to 1.944 and 6.619. In addition to confirm the relationship between waistline level and reduced e GFR, we also found the prevalence of e GFR in population with increased blood pressure and glucose rised significantly compared to 2007(5.26% VS 2.93%, P=0.027 and 7.23% VS 2.97%, P=0.001, respectively). Increased waistline, blood pressure and glucose level were risk factors for CKD both in 2007 and 2012. And the risk of reduced glomerular filtration rate increased with blood pressure and glucose level with an OR of 1.799[95%CI(1.062-3.049)] and 2.433[95%CI(1.401-4.225)].4. Trends in the relationship between the number of MS component and CKD. In two surveys, we found the number of MS component associated with albuminuria and reduced glomerular filtration rate. Compared to those without any components of the MS, the ORs(95% CI) of albuminuria and reduced glomerular filtration rate were 2.525[95%CI(1.160-5.500)],12.690[95%CI(5.513-29.212)] and 4.735[95%CI(1.084-20.689)],42.300[95%CI(9.918-180.406)] in 2007 and 2.064 [95%CI(1.158-3.679)],11.050 [95%CI(7.083-17.238)] and 18.214 [95%CI(5.467-60.680)], 56.667 [95%CI(16.588-193.584)] in 2012 among population with 4 and 5 MS components.5. Effect for occurrence of CKD. The highest albuminuria and reduced glomerular filtration rate incidence(7.93% and 4.41%) was found in those population who conformed to MS diagnosis both in 2007 and 2012, further risk assessment showed that the OR was 2.943[95%CI(1.650 5.249)] and 2.759[95%CI(1.269-5.999)] for albuminuria and reduced glomerular filtration rate.Conclusions1. This is the first innovative cohort study on trends in the risk factors for CKD in China.2. Although the age, race, obesity, hypertension, diabetes and hyperuricemia still were risk factors for CKD in zhengzhou adults, but the impact on CKD has changed,and female was no longer the risk of CKD.3. MS and its related components closely related to albuminuria and reduced e GFR.Part Ⅲ The epidemiology of chronic kidney disease among adults in China: a systematic review and meta-analysisMethodsAccording to the keywords, literatures were searched in three Chinese databases, wanfang data, CNKI and VIP. We screened literatures in line with the study according to predefined inclusion/exclusion criteria. Data of corresponding variable were extracted in these literatures and the database was established. Finally data from these literatures were analyzed by meta-analysis using R 3.1.1 for windows.Results1. Results of literature search. 149 qualified literatures were searched. 29 qualified literatures included 279,668 subjects from 20 provinces or municipalities were included in the meta-analysis, finally.2. Mate-analysis of the prevalence of albuminuria, heamaturia, and reduced e GFR in chinese adults. The mate-analysis including 29 studies showed that the prevalence of albuminuria and reduced e GFR was 6.28%[95%CI(6.17%-6.39%)] and 2.69%[95%CI(2.62%-2.76%)] without publication biases in literatures(P = 0.8011 and P = 0.2241). The heamaturia prevalence was 5.92%[95%CI(5.83%-6.01%)] with publication bias(P = 0.03572).3. Mate-analysis of the prevalence of CKD in Chinese adults. The mate-analysis of 29 included studies showed that the prevalence of CKD was 12.50% [95%CI(12.37%-12.63%)]. there was no publication bias(P = 0.5888)in relevant literatures. Further analysis indicated that the prevalence of CKD1, CKD2 and CKD3 were 8.38%[95%CI(8.25%-8.52%)], 4.02%[95%CI(3.92%-4.11%)] and1.65%[95%CI(1.59%-1.72%)] separately.4. Mate-analysis of the prevalence of CKD and kidney damage in male and femal Chinese adults. Sex distribution were summarized and described in 17 studies in detail, which was included in this meta-analysis. Results indicated that the prevalence of CKD in male was 9.77%[95%CI(9.56%-9.98%)], the prevalence of proteinuria, heamaturia, and reduced e GFR in male were 7.02%[95%CI(6.81%-7.24%)], 3.79%[95%CI(3.65%-3.94%)] and 3.36% [95%CI(3.22%-3.50%)] separately, while the prevalence of CKD in female was12.88%[95%CI(12.59%-13.16%)], the prevalence of proteinuria, heamaturia, and reduced e GFR in female were 5.85%[95%CI(5.63%-6.08%)],8.70%[95%CI(8.45%-8.95%)] and 2.73%[95%CI(2.58%-2.89%)], respectively.5. Mate-analysis of the prevalence of CKD and kidney damage in population with different age. Age distribution were defined and described in 15 studies, which was included in this meta-analysis. Results indicated that the prevalence of CKD in people under the age of 60 and people aged 60 s or older were 11.14%[95%CI(10.98%-11.30%)] and 23.34%[95%CI(22.86%-23.83%)] respectively, and there was no publication(P = 0.8147 and P= 0.8147). The mate-analysis of the prevalence of markers of kidney damage showed that the prevalence of proteinuria, heamaturia, and reduced e GFR in people under the age of 60 were 5.56%[95%CI(5.41%-5.71%)]、5.45%[95%CI(5.33%-5.57%)] and 1.93%[95%CI(1.84%-2.02%)] respectively, while the prevalence of proteinuria, heamaturia, and reduced e GFR in people aged 60 s or older were8.73%[95%CI(8.42%-9.04%)], 10.83%[95%CI(10.52%-11.14%)] and 8.78%[95%CI(8.33%-9.26%)] respectively.Conclusions1. The prevalence of CKD was 12.50% among Chinese adults, and most in CKD 1-2 stage.2. Femal population had high CKD and heamaturia prevalence, but the the prevalence of albuminuria and reduced e GFR was low compared to male.3. The situation of CKD prevalence was even severe in elderly population.Full text conclusion and innovation1. This study was the first epidemiological cohort study of CKD in our country with strong innovation. The results confirmed the prevalence and risk factors for CKD have trended, which provided data support for the timely adjustion in strategy for the prevention and control of CKD.2. This study is the first Meta analysis of epidemiological investigation of CKD in China. We obtained more representative data about CKD and reveal the prevalence of CKD in different gender and age through Meta analysis. it will be great significant for the prevention and control of CKD in our country.