Prevalence Of Impaired Kidney Function Research Articles

PS-P05-5: CHANGES IN BLOOD PRESSURE CONTROL, TARGET ORGAN DAMAGE AND CARDIOVASCULAR RISK FACTORS IN HYPERTENSIVE SUBJECTS UNDER ANTIHYPERTENSIVES DURING 9 YEARS

Objective: Since an increase in blood pressure is one of the most important risk factors for cardiovascular morbidity and mortality, appropriate blood pressure control is necessary to prevent target organ damages and cardiovascular diseases. We investigated changes in blood pressure control, target organ damage and cardiovascular risk factors of hypertensive subjects under antihypertensive medications from 2010 to 2019. Design and Methods: A total of 1679 and 1884 hypertensive subjects under antihypertensive medications (62.8 ± 9.8 and 65.8 ± 9.4 year-old, respectively) who visited our hospital for physical checkup in 2010 and 1019, respectively, were enrolled. Subjects were divided into two groups; controlled (blood pressure < 140/90mmHg) and not-controlled groups (blood pressure > = 140/90mmHg). Target organ damage defined as left ventricular hypertrophy (LVH) on electrocardiogram (Sokolow-Lyon voltage > 3.8 mV and/or Cornell product > 2440 mm ms) or decline of estimated glomerular filtration rate (eGFR; < 60 mL/min per 1.73 m2) and other cardiovascular risk factors were investigated. Results: The results are summarized in the table. Blood pressure control was generally improved during the 9 years though the mean age of subjects was increased. The prevalence of impaired kidney function but not LVH and the number of subjects with risk factors were increased during the period. Sub-analysis in 537 subjects who visited in both 2010 and 2019 were performed and similar results were obtained (data not shown). Conclusions: Although blood pressure control was improved, total management of hypertensive subjects was not appropriate. Management of risk factors other than hypertension as well as blood pressure control is necessary in hypertensive subjects for extension of healthy life expectancy.

Measurement of kidney function in Malawi, South Africa, and Uganda: a multicentre cohort study

The burden of kidney disease in many African countries is unknown. Equations used to estimate kidney function from serum creatinine have limited regional validation. We sought to determine the most accurate way to measure kidney function and thus estimate the prevalence of impaired kidney function in African populations. We measured serum creatinine, cystatin C, and glomerular filtration rate (GFR) using the slope-intercept method for iohexol plasma clearance (mGFR) in population cohorts from Malawi, Uganda, and South Africa. We compared performance of creatinine and cystatin C-based estimating equations to mGFR, modelled and validated a new creatinine-based equation, and developed a multiple imputation model trained on the mGFR sample using age, sex, and creatinine as the variables to predict the population prevalence of impaired kidney function in west, east, and southern Africa. Of 3025 people who underwent measured GFR testing (Malawi n=1020, South Africa n=986, and Uganda n=1019), we analysed data for 2578 participants who had complete data and adequate quality measurements. Among 2578 included participants, creatinine-based equations overestimated kidney function compared with mGFR, worsened by use of ethnicity coefficients. The greatest bias occurred at low kidney function, such that the proportion with GFR of less than 60 mL/min per 1·73 m2 either directly measured or estimated by cystatin C was more than double that estimated from creatinine. A new creatinine-based equation did not outperform existing equations, and no equation, including the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 race-neutral equation, estimated GFR within plus or minus 30% of mGFR for 75% or more of the participants. Using a model to impute kidney function based on mGFR, the estimated prevalence of impaired kidney function was more than two-times higher than creatinine-based estimates in populations across six countries in Africa. Estimating GFR using serum creatinine substantially underestimates the individual and population-level burden of impaired kidney function in Africa with implications for understanding disease progression and complications, clinical care, and service provision. Scalable and affordable ways to accurately identify impaired kidney function in Africa are urgently needed. The GSK Africa Non-Communicable Disease Open Lab. For the Luganda, Chichewa and Xitsonga translations of the abstract see Supplementary Materials section.

Abnormal Kidney Function in Anorexia Nervosa

Source: Gurevich E, Steiling S, Landau D. Incidence of impaired kidney function among adolescent patients hospitalized with anorexia nervosa. JAMA Netw Open. 2021;4(11):e2134908. doi:10.1001/jamanetworkopen.2021.34908Investigators from Schneider’s Children’s Medical Center of Israel, Petach Tikva, Israel, and Sackler School of Medicine, Tel Aviv, Israel, conducted a retrospective study to assess kidney function in children and adolescents hospitalized with anorexia nervosa (AN) and identify predictors of impaired kidney function (IKF) in these patients. For the study, discharge diagnoses were used to identify youths, 9-18 years old, hospitalized at Schneider’s Children’s Medical Center of Israel for AN between 2010 and 2019. Only youths with a first-time hospitalization for AN were included in the study. Patients with AN were age- and sex-matched to a random sample of control children with normal serum creatinine (SCr) levels, hospitalized for other reasons during the same period. The medical records of study participants were reviewed and data on demographics, BMI, and SCr abstracted. In patients with AN, data on free triiodothyronine (FT3) level and minimal heart rate (HR) also were collected. Kidney function was assessed in study participants using maximal SCr levels, minimal estimated glomerular filtration rate (eGFR) and SCr/BMI ratio during the hospitalizations. These parameters were compared in AN patients and controls using chi-square or Fisher exact tests. AN patients were classified as having IKF if their minimal eGFR during the hospitalization was <90 mL/min/1.73 m2. Stepwise regression was used to identify predictors of IKF in AN patients.A total of 395 youths with AN and 495 controls were included in the analyses. The mean age of AN patients was 14.6 ± 2.2 years, and 298 (81.6%) were female. The median BMI percentile in those with AN was 12.3, compared to 49 in controls (P <0.001). Parameters of kidney function were significantly different between AN patients and controls including maximal SCr (mean values, 0.68 ± 0.15 mg/dL and 0.54 ± 0.14 mg/dL, respectively; P <0.001), SCr/BMI (mean values, 4% ± 1.2% and 2.8% ± 1.1%, respectively; P <0.001), and minimal eGFR (mean values, 99.8 ± 22.0 mL/min/1.73 m2 and 124 ± 26.5 mL/min/1.73 m2, respectively; P <0.001). Among those with AN, 146 (37%) met criteria for IKF compared to 0 control patients. In the group of AN patients, those with IKF had a significantly lower minimal HR than those without IKF (mean, 44 vs 56 beats per minute; P = 0.001) and lower FT3 levels (mean, 3.5 vs 4.1 pmol/L; P = 0.001); there was no significant difference between groups for mean BMI. Independent predictors of IKF in AN patients included SCr/BMI ratio, minimal HR, and systolic and diastolic blood pressure.The authors conclude that IKF is common in youths hospitalized with AN.Dr Sanchez-Kazi has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.AN has a prevalence rate between 0.1% and 2.2%.1 As previously reported, IKF is a known complication of AN with multifactorial etiologies including chronic dehydration, electrolyte derangements, and abuse of certain medications.2 Chronic hypokalemia has been associated with acute kidney injury (AKI) and chronic kidney disease.2 Other electrolyte abnormalities reported with AN and during refeeding include hypophosphatemia, hypomagnesemia, and hyponatremia. (See AAP Grand Rounds. 2021;45(2):16.)2,3 Kidney biopsy has shown interstitial fibrosis, evidence of ischemic injury, and hypokalemic nephropathy.2The biggest limitation of the current study, and all studies of AN, is the inability to accurately determine eGFR. Using creatinine and correction of eGFR per body surface is likely inaccurate due to low muscle mass. The prevalence of IKF in AN may increase or decline depending on the accuracy of eGFR. Using nuclear GFR may be more precise, although cumbersome, or perhaps measurement of serum cystatin C.4,5 Cystatin C, a low molecular weight protein secreted by all nucleated cells, is independent of muscle mass.4,5 BMI was used to correct for low muscle mass in the current study, although this method has not been verified. It is interesting to note that admission BMI did not correlate with eGFR, but minimal heart rate did. Does this suggest that cardiac abnormalities may contribute to reduction in kidney perfusion in AN?Although the current study was performed in Israel, AN is universal. AKI has been associated with longer hospitalization and increased morbidity not only in AN but also in other non-AN conditions.6In adolescent patients hospitalized with recently diagnosed AN, kidney function often is impaired and needs to be followed closely.The global pandemic of COVID-19 has been associated with a marked increase incidence of eating disorders.7 Social distancing, changes in food access and habits, and social pressure exerted through the internet appear to be contributory. Recent AAP guidelines outline the pediatrician’s role in detection and management of children and adolescents with disordered eating.8

Prevalence of impaired kidney function in patients with long-term lithium treatment: A systematic review and meta-analysis.

Although lithium renal effects have been extensively investigated, prevalence rates of chronic kidney disease (CKD) in lithium-treated patients vary. Our aim was to provide prevalence estimates and related moderators. We performed a systematic review in PubMed/Embase until November 01, 2021, conducting a random effects meta-analysis of studies evaluating CKD prevalence rates in lithium-treated patients calculating overall prevalence ±95% confidence intervals (CIs). Meta-regression analyses included sex, age, body mass index, smoking, hypertension, diabetes, cardiovascular disease, lithium-treatment dose, duration, and blood levels. Subgroup analyses included sample size, diagnoses, and study design. Pooled odds ratios (OR) were estimated for studies including patients receiving nonlithium treatment. Study quality was assessed using the Newcastle-Ottawa scale. Five, nine, and six trials were rated as high, fair, and low quality, respectively. In 20studies (n=25,907 patients), we estimated an overall prevalence of 25.5% (95% CI=19.8-32.2) of impaired kidney function; despite lack of differences (p=0.18), prevalence rates were higher in elderly samples than mixed samples of elderly and nonelderly (35.6%, 95% CI=21.4-52.9, k=2, n=3,161 vs. 25.1%, 95% CI=19.1-31.3, k=18, n=22,746). Prevalence rates were associated with longer lithium treatment duration (p=0.04). Cross-sectional studies provided lower rates than retrospective studies (14.5%, 95% CI=13.5-15.5, k=6, n=4,758 vs. 29.5%, 95% CI=22.1-38.0, k=12, n=17,988, p<0.001). Compared with 722,529 patients receiving nonlithium treatment, the OR of impaired kidney function in 14,187lithium-treated patients was 2.09 (95% CI=1.24-3.51, k=8, p=0.005). One-fourth of patients receiving long-term lithium may develop impaired kidney function, although research suffers from substantial heterogeneity between studies. This risk may be twofold higher compared with nonlithium treatment and may increase for a longer lithium treatment duration.

Prevalence and risk factors for impaired kidney function in the district of Anuradhapura, Sri Lanka: a cross-sectional population-representative survey in those at risk of chronic kidney disease of unknown aetiology

BackgroundOver the last 20 years there have been reports of a form of chronic kidney disease of unknown cause (CKDu) affecting rural communities in the North Central Province of Sri Lanka. Valid prevalence estimates, using a standardised methodology, are needed to assess the burden of disease, assess secular trends, and perform international comparisons.MethodsWe conducted a cross-sectional representative population survey in five study areas with different expected prevalences of CKDu. We used a proxy definition of CKDu involving a single measure of impaired kidney function (eGFR< 60 mL/min/1.7m2, using the CKD-Epi formula) in the absence of hypertension, diabetes or heavy proteinuria.ResultsA total of 4803 participants (88.7%) took part in the study and 202 (6.0%; 95% CI 5.2–6.8) had a low eGFR in the absence of hypertension, diabetes and heavy proteinuria and hence met the criteria for proxy CKDu. The proportion of males (11.2%; 95% CI 9.2–13.1) were triple than the females (3.7%; 95% CI 2.9–4.5). Advancing age and history of CKD among parents or siblings were risk factors for low GFR among both males and females while smoking was found to be a risk factor among males.ConclusionsThese data, collected using a standardised methodology demonstrate a high prevalence of impaired kidney function, not due to known causes of kidney disease, in the selected study areas of the Anuradhapura district of Sri Lanka. The aetiology of CKDu in Sri Lanka remains unclear and there is a need for longitudinal studies to describe the natural history and to better characterise risk factors for the decline in kidney function.

Impaired renal function in a rural Ugandan population cohort.

Background: Kidney disease is an important cause of morbidity and mortality globally. However, there are limited data on the prevalence of impaired kidney function in sub-Saharan Africa. We aimed to determine the prevalence of reduced kidney function and associated factors in a rural Ugandan population. Methods: We undertook a study of a representative sample of the General Population Cohort in South-western Uganda. We systematically collected data on cardiovascular disease risk factors, anthropometric measurements and blood tests including haemoglobin, HIV, HbA1c and serum creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-Epi equation, without the race component of the equation. Results: A total of 5,979/6,397 (93.5%) participants had valid creatinine results. The mean age was 39 years (Range:16-103 years) and 3,627 (60.7%) were female. HIV prevalence was 9.7% and about 40% of the population were pre-hypertensive or hypertensive. The mean serum creatinine level was 0.75 mg/dl (95% CI 0.74-0.75), and the average eGFR was 109.3 ml/min/1.73 m 2 (95% CI 108.8-109.9). The overall prevalence of eGFR <60 ml/min/1.73 m 2 was 1.64% (98/5,979) (95% CI 1.34-1.99). Additionally, 4,792(80.2%) were classified as normal eGFR (≥90 ml/min/1.73 m 2), 1,089(18.2%) as low eGFR (60-89 ml/min/1.73 m 2), 91(1.52%) as moderately reduced eGFR (30-59 ml/min/1.73 m 2), 4(0.07%) as severely reduced eGFR (15-29 ml/min/1.73 m 2), and 3(0.05%) classified as having kidney failure (eGFR<15 ml/min/1.73 m 2). When age-standardised to the WHO Standard Population the prevalence of eGFR<60 ml/min/1.73 m 2 was 1.79%. Age above 35 years and the presence of hypertension (OR 2.86, 95% CI 1.15-7.08) and anaemia (OR 2.14, 95% CI 1.12-4.09) were associated with eGFR<60 ml/min/1.73 m 2. Conclusion: In a systematic survey of people in rural Uganda, we found a substantial proportion had eGFR<60 ml/min/1.73 m 2. More population based studies are needed to further characterize kidney disease in sub-Saharan Africa.

Impaired renal function in a rural Ugandan population cohort

Background: Kidney disease is an important cause of morbidity and mortality globally. However, there are limited data on the prevalence of impaired kidney function in sub-Saharan Africa. We aimed to determine the prevalence of reduced kidney function and associated factors in a rural Ugandan population. Methods: We undertook a study of a representative sample of the General Population Cohort in South-western Uganda. We systematically collected data on cardiovascular disease risk factors, anthropometric measurements and blood tests including haemoglobin, HIV, HbA1c and serum creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-Epi formula, without the race component of the equation. Results: A total of 5,979/6,397 (93.5%) participants had valid creatinine results. The mean age was 39 years (Range: 16-103 years) and 3,627 (60.7%) were female. HIV prevalence was 9.7% and about 40% of the population were pre-hypertensive or hypertensive. The mean serum creatinine level was 0.75 mg/dl (95% CI 0.74–0.75), and the average eGFR was 109.3 ml/min/1.73 m2 (95% CI 108.8–109.9). The overall prevalence of eGFR &lt;60 ml/min/1.73 m2 was 1.64% (98/5,979) (95% CI 1.34–1.99). Additionally, 4,792 (80.2%) were classified as normal eGFR (≥90 ml/min/1.73 m2), 1,089 (18.2%) as low eGFR (60–89 ml/min/1.73 m2), 91 (1.52%) as moderately reduced eGFR (30–59 ml/min/1.73 m2), 4 (0.07%) as severely reduced eGFR (15-29 ml/min/1.73 m2), and 3 (0.05%) classified as having kidney failure (eGFR &lt;15 ml/min/1.73 m2). When age-standardised to the WHO Standard Population the prevalence of eGFR&lt;60 ml/min/1.73 m2 was 1.79%. Age above 35 years and the presence of hypertension (OR 2.86, 95% CI 1.15-7.08) and anaemia (OR 2.14, 95% CI 1.12-4.09) were associated with eGFR&lt;60 ml/min/1.73 m2. Conclusion: In a systematic survey of people in rural Uganda, we found a substantial proportion had eGFR&lt;60 ml/min/1.73 m2, and this was strongly associated with high blood pressure and anaemia.

Impaired renal function in a rural Ugandan population cohort

Background: Kidney disease is an important cause of morbidity and mortality globally. However, there are limited data on the prevalence of impaired kidney function in sub-Saharan Africa. We aimed to determine the prevalence of reduced kidney function and associated factors in a rural Ugandan population. Methods: We undertook a study of a representative sample of the General Population Cohort in South-western Uganda. We systematically collected data on cardiovascular disease risk factors, anthropometric measurements and blood tests including haemoglobin, HIV, HbA1c and serum creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-Epi equation, without the race component of the equation. Results: A total of 5,979/6,397 (93.5%) participants had valid creatinine results. The mean age was 39 years (Range:16-103 years) and 3,627 (60.7%) were female. HIV prevalence was 9.7% and about 40% of the population were pre-hypertensive or hypertensive. The mean serum creatinine level was 0.75 mg/dl (95% CI 0.74–0.75), and the average eGFR was 109.3 ml/min/1.73 m 2 (95% CI 108.8–109.9). The overall prevalence of eGFR <60 ml/min/1.73 m 2 was 1.64% (98/5,979) (95% CI 1.34–1.99). Additionally, 4,792(80.2%) were classified as normal eGFR (≥90 ml/min/1.73 m 2), 1,089(18.2%) as low eGFR (60–89 ml/min/1.73 m 2), 91(1.52%) as moderately reduced eGFR (30–59 ml/min/1.73 m 2), 4(0.07%) as severely reduced eGFR (15-29 ml/min/1.73 m 2), and 3(0.05%) classified as having kidney failure (eGFR<15 ml/min/1.73 m 2). When age-standardised to the WHO Standard Population the prevalence of eGFR<60 ml/min/1.73 m 2 was 1.79%. Age above 35 years and the presence of hypertension (OR 2.86, 95% CI 1.15-7.08) and anaemia (OR 2.14, 95% CI 1.12-4.09) were associated with eGFR<60 ml/min/1.73 m 2. Conclusion: In a systematic survey of people in rural Uganda, we found a substantial proportion had eGFR<60 ml/min/1.73 m 2. More population based studies are needed to further characterize kidney disease in sub-Saharan Africa.

Impaired renal function in a rural Ugandan population cohort

Background: Chronic kidney disease (CKD) is an important cause of morbidity and mortality globally. However, there are limited data on the prevalence of impaired kidney function in sub-Saharan Africa. We aimed to determine the prevalence of CKD and associated factors in a rural Ugandan population. Methods: We undertook a study of a representative sample of the General Population Cohort in South-western Uganda. We systematically collected data on cardiovascular disease risk factors, anthropometric measurements and blood tests for haemoglobin, HIV, HbA1c, Hepatitis B and C and serum creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the CKD-Epi formula, without the race component of the equation. Results: A total of 5,979/6,397 (93.5%) participants had valid creatinine results. The mean age was 39 years (Range: 16-103 years) and 3,627 (60.7%) were female. HIV prevalence was 9.7% and about 40% of the population were pre-hypertensive or hypertensive. The mean serum creatinine level was 0.75 mg/dl (95% CI 0.74–0.75), and the average eGFR was 109.3 ml/min/1.73 m2 (95% CI 108.8–109.9). The overall prevalence of CKD (eGFR &lt;60 ml/min/1.73 m2) was 1.64% (98/5,979) (95% CI 1.34–1.99). Additionally, 4,792 (80.2%) were classified as normal (eGFR ≥90 ml/min/1.73 m2), 1,089 (18.2%) as low (eGFR 60–89 ml/min/1.73 m2), 91 (1.52%) as moderate (eGFR 30–59 ml/min/1.73 m2), 4 (0.07%) as severe (eGFR 15-29 ml/min/1.73 m2), and 3 (0.05%) classified as having kidney failure (eGFR &lt;15 ml/min/1.73 m2). When age-standardised to the WHO Standard Population the prevalence of CKD was 1.79%. Age above 35 years (OR 78.3, 95% CI 32.3–189), and the presence of hypertension (OR 2.98, 95% CI 1.47-6.02) and anaemia (OR 2.47, 95% CI 1.37-4.42) were associated with CKD. Conclusion: We found a substantial prevalence of CKD in rural Uganda, strongly associated with high blood pressure and anaemia.

Impaired Kidney Function and Associated Factors Among Rural Adults With Disabilities in Taiwan.

The results of numerous studies indicate that people with disabilities seek more healthcare than those who are not disabled, particularly for conditions such as chronic kidney disease, cardiovascular disease, and obesity. However, little is known about the incidence of impaired kidney function and its associated factors among adults with disabilities in Taiwan. The aim of this study was to explore the prevalence and factors associated with impaired kidney function among adults with disabilities. This descriptive study was nurse led and was conducted as part of a health promotion program for disadvantaged rural adults with disabilities in Chiayi County, Taiwan. Health screening and a health needs survey were conducted between July and December 2013. Kidney function, physiological biomarkers, health-related behaviors, and demographic characteristics were examined. Eight hundred ten rural adults with disabilities were enrolled. The most common disabilities included physical-related disability (33.1%), intellectual-related disability (26.7%), and hearing and vision impairment (18.6%). The prevalence of impaired kidney function in this population was 85%. According to classification for chronic kidney disease, 68.6% were in Stages 1-2, and 16.8% were in Stages 3-4. Univariate analysis showed that impaired kidney function was significantly associated with lower educational level (p < .001), hearing or vision impairment (p < .001), being overweight or obese (p < .05), high systolic blood pressure (p < .01), fasting blood glucose (p < .001), total cholesterol (p < .001), total triglyceride (p < .05), older age (p < .001), smoking (p < .05), chewing betel nuts (p = .001), and low levels of participation in social activities (p < .05). The final logistic regression model showed that residents with disabilities who were older or had less education, high fasting blood glucose, and high total cholesterol tended to have impaired kidney function after adjustment for other potential confounding variables. Most participants showed impaired kidney function. The factors that were found to relate significantly to this impairment include being overweight, having hyperlipidemia, having hypertension, having high fasting blood glucose, and having an unhealthy lifestyle. Because of the lack of symptoms during the early stages of chronic kidney disease, a community-based health promotion program for these factors is an important element in health advocacy for this vulnerable population.

Prevalence of Impaired Kidney Function in the German Elderly: Results from the Berlin Aging Study II (BASE-II)

Background: In aging populations with an ever-growing burden of risk factors such as obesity, diabetes, and hypertension, chronic kidney disease (CKD) is on the rise. However, little is known about its exact prevalence among elderly adults, and often albuminuria is not included in the definition of CKD. Moreover, novel equations for the estimated glomerular filtration rate (eGFR) have recently emerged, which have not been applied comprehensively to older adults. Data on CKD awareness among the elderly are sparse. Objectives: To determine the prevalence of CKD among older adults by eGFR and albumin/creatinine ratio (ACR), compare the performance of 6 established and novel eGFR formulas, explore risk factors, and determine the awareness of CKD in a large cohort of community-dwelling elderly from Germany. Methods: A total of 1,628 subjects from the Berlin Aging Study II (BASE-II) were included in this analysis (mean age 68.7 years; 51.2% female). Extensive cross-sectional data on sociodemographics, lifestyle, medication, and diagnoses were inquired during structured interviews and a medical examination, and blood and urine parameters were measured. Results: In all, 77.1% of the subjects had hypertension, 12.4% had diabetes, and 18.3% were obese. The prevalence of CKD strongly depended on the eGFR equations used: 25.4% (full age spectrum [FAS] equation), 24.6% (Berlin Initiative Study), 23.1% (Lund-Malmö revised), 19.3% (Cockcroft-Gault), 16.4% (Chronic Kidney Disease-Epidemiology Collaboration [CKD-EPI]), and 14.7% (Modification of Diet in Renal Disease [MDRD]). Of the subjects with an eGFR_FAS <60 mL/min/1.73 m² and/or an ACR >30 mg/g, only 3.9% were aware of having CKD. Polypharmacy, age, BMI, coronary artery disease, non-HDL cholesterol, and female sex were independently associated with CKD. Conclusions: CKD is prevalent among older adults in Germany, but awareness is low. The FAS equation detects higher rates of CKD than MDRD and CKD-EPI, which are most widely used at present. Also, when CKD is defined based on eGFR and albuminuria, considerably more people are identified than by eGFR alone. Finally, polypharmacy is associated with an increased risk for CKD in the elderly.

Chronic kidney disease in primary care in Germany

The continuing growth of the population with end-stage renal disease (ESRD) in the past two decades has been recognized as a global health burden. In 2002, a definition of chronic kidney disease (CKD) was introduced and different categories of CKD have been reported in the general population. In this study, we examined the prevalence of CKD in primary health care in Germany. From 2004 to 2007 the prevalence of CKD was estimated in the Diabetes Cardiovascular Risk-Evaluation Targets and Essential Data for Commitment of Treatment (DETECT) study using the Simplified Modification of Diet in Renal Disease (MDRD) and the CKD Epidemiology Collaboration (CKD-EPI) equations. A sample of 4,080 subjects were analysed with detailed laboratory and comorbidity assessment from 851 primary care centres across Germany. The prevalence of CKD (≤60 ml/min/1.73 m2) was 27.9 % estimated by CKD-EPI equation (MDRD eGFR 36.1 %) and the prevalence of CKD increased with age and during follow-up. The overall decline in eGFR per year was −1.83 ml/min/year (CKD-EPI). Women have shown a higher decline in eGFR than men. The prevalence of CKD was highest in coronary artery disease patients, followed by diabetes mellitus and arterial hypertension. Individuals with diabetes mellitus have shown the highest progress developing CKD. In this representative sample of patients seeking medical advice in primary care, the prevalence of impaired kidney function was almost one third. Given the therapeutic implications, our results call for focused measures to increase the awareness of CKD in primary care.

Nonalcoholic fatty liver is not associated with incident chronic kidney disease: a large histology-based comparison with healthy individuals.

Nonalcoholic steatohepatitis or fibrosis is associated with the increased prevalence of impaired kidney function. It is not known whether nonalcoholic fatty liver (NAFL), which is steatosis without inflammation or fibrosis, is associated with renal impairment as these individuals are not candidates for liver biopsy. The study group included all liver donors who underwent a preoperative liver biopsy for various reasons. NAFL was defined as more than 5% hepatocytes having steatosis and no changes of steatohepatitis and/or fibrosis. Individuals with NAFL were compared with individuals with normal liver histology. Estimated glomerular filtration rate was calculated with the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration methods. The mean age of the study group was 35±10.3 years and the mean BMI was 26±3.2 kg/m. A total of 187 adults having NAFL (80 men) were compared with 186 (88 men) individuals with normal liver histology (controls). Individuals with steatosis had significantly higher BMI (26.8±3.5 vs. 25.5±3.8 kg/m, P<0.001) and serum alanine transaminase levels (33.8±13.3 vs. 27.2±9.8 IU/l, P<0.000). There was no significant difference in the estimated glomerular filtration rate between the normal histology group and the NAFL group with Modification of Diet in Renal Disease (115±21.8 vs. 114.4±23.2 ml/min, P=0.803) and Chronic Kidney Disease Epidemiology Collaboration methods (113.6±14.8 vs. 113±14.7 ml/min, P=0.668). There was no significant difference as regards serum creatinine (0.73±0.16 vs. 0.74±0.16 mg%, P=0.536), proteinuria (P=0.121), diabetes (1 vs. 4, P=0.372), and hypertension (2 vs. 6, P=0.174) in individuals of both groups. Presence of NAFL does not adversely affect renal function.

Measuring the population burden of chronic kidney disease: a systematic literature review of the estimated prevalence of impaired kidney function

Internationally, there have been substantial efforts to improve the early identification of chronic kidney disease (CKD), with a view to improving survival, reducing progression and minimizing cardiovascular morbidity and mortality. In 2002, a new and globally adopted definition of CKD was introduced. The burden of kidney function impairment in the population is unclear and widely ranging prevalence estimates have been reported. We conducted a systematic literature review, searching databases to June 2009. We included all adult population screening studies and studies based on laboratory or clinical datasets where the denominator was clear. Studies reporting prevalence estimates based on at least one eGFR <60 mL/min/1.73m(2) or elevated creatinine above a stated threshold were included. Study design and quality were explored as potential factors leading to heterogeneity. We identified 43 eligible studies (57 published reports) for inclusion. Substantial heterogeneity was observed with estimated prevalence (0.6-42.6%). The included studies demonstrated significant variation in methodology and quality that impacted on the comparability of their findings. From the higher quality studies, the six studies measuring impaired kidney function (iKF) using estimated glomerular filtration rate in community screening samples reported a prevalence ranging from 1.7% in a Chinese study to 8.1% in a US study, with four reporting an estimated prevalence of 3.2-5.6%. Heterogeneity was driven by the measure used, study design and study population. In the general population, estimated iKF, particularly eGFR 30-59 mL/min/1.73m(2) was common with prevalence similar to diabetes mellitus. Appropriate care of patients poses a substantial global health care challenge.

Racial Differences in the Prevalence of Chronic Kidney Disease among Participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Cohort Study

The racial disparity in the incidence of ESRD exemplified by the three- to four-fold excess risk among black compared with white individuals in the United States is not reflected in the prevalence of less severe degrees of impaired kidney function among black compared with white individuals. The four-variable Modification of Diet in Renal Disease study equation was used to evaluate the black-to-white prevalence of impaired kidney function with increasing severity of impairment among participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a nationally representative, population-based cohort of individuals who are 45 yr and older. An estimated GFR (eGFR)<60 ml/min per 1.73 m2 was present in 43.3% of the 20,667 REGARDS participants and was slightly less prevalent among black than white patients (33.7 versus 49.9%; prevalence odds ratio 0.51; 95% confidence interval [CI] 0.48 to 0.54). The lower prevalence among black patients was not uniform as eGFR declined. After controlling for other patient characteristics, the black-to-white odds ratio was 0.42 (95% CI 0.40 to 0.46) at an eGFR of 50 to 59 ml/min per 1.73 m2 and increased to 1.73 (95% CI 1.02 to 2.94) at an eGFR of 10 to 19 ml/min per 1.73 m2. The disparity in prevalence of impaired kidney function among white compared with black patients reversed as the severity of impaired kidney function increased. Factors that are responsible for the increasing prevalence of severely impaired kidney function among black patients remain to be determined.

Prevalence of Impaired Kidney Function in Hospitalized Hypertensive Patients in Maiduguri, Nigeria

Prevalence of Impaired Kidney Function in Hospitalized Hypertensive Patients in Maiduguri, Nigeria

The need for optimal and coordinated management of CKD

The prevalence of impaired kidney function has been estimated to be between 10% and 20% of adult populations in most countries worldwide. Reduced kidney function has been recognized as a risk factor for poor outcomes, and thus requires attention. Key aspects of management of CKD have been defined for referred populations, but not necessarily for those unreferred. In order to improve patient outcomes, there is a need to take a more holistic approach to the problem, by coordinating the efforts of policy makers, those involved in health care system redesign, clinicians, and researchers. In so doing, there should be an improvement in both identification and management of patients with impaired kidney function, whether cared for by primary care physicians, specialists, or nephrologists, and irrespective of the health care system.