Burden and predictors of hypertension in India: results of SEEK (Screening and Early Evaluation of Kidney Disease) study.

BACKGROUND: Hypertension (HTN) is one of the major causes of cardiovascular morbidity and mortality. The objective of the study was to investigate the burden and predictors of HTN in India. METHODS: 6120 subjects participated in the Screening and Early Evaluation of Kidney disease (SEEK), a community-based screening program in 53 camps in 13 representative geographic locations in India. Of these, 5929 had recorded blood pressure (BP) measurements. Potential predictors of HTN were collected using a structured questionnaire for SEEK study. RESULTS: HTN was observed in 43.5% of our cohort. After adjusting for center variation (p < 0.0001), predictors of a higher prevalence of HTN were older age ≥ 40 years (p < 0.0001), BMI of ≥ 23 Kg/M2 (p < 0.0004), larger waist circumference (p < 0.0001), working in sedentary occupation (p < 0.0001), having diabetes mellitus (p < 0.0001), having proteinuria (p < 0.0016), and increased serum creatinine (p < 0.0001). High school/some college education (p = 0.0016), versus less than 9th grade education, was related with lower prevalence of HTN. Of note, proteinuria and CKD were observed in 19% and 23.5% of HTN subjects. About half (54%) of the hypertensive subjects were aware of their hypertension status. CONCLUSIONS: HTN was common in this cohort from India. Older age, BMI ≥ 23 Kg/M2, waist circumference, sedentary occupation, education less, diabetes mellitus, presence of proteinuria, and raised serum creatinine were significant predictors of hypertension. Our data suggest that HTN is a major public health problem in India with low awareness, and requires aggressive community-based screening and education to improve health.

Prevalence of vitamin D deficiency in Saudi adults.

OBJECTIVE: To determine the prevalence of vitamin D deficiency in healthy Saudi adults. METHODS: A cross-sectional study carried out as part of the screening and early evaluation of kidney disease project. Vitamin D was measured in subjects recruited at 2 screening camps in Riyadh, Saudi Arabia, between March to May 2008. Subjects from the 2 large commercial centers in Riyadh aged ≥18 years and Saudi nationals were invited. RESULTS: The study sample comprised of 488 subjects. The mean age of the subjects was 37.43 (11.32) years, of which 50.2% (n=245) were males. Twenty-nine percent of subjects were in the vitamin D deficiency group, 22.7% were in the relative insufficiency group, and 47.5% had normal levels of 25-hydroxy vitamin D. We observed that female gender was an independent predictor of vitamin D deficiency or insufficiency (odds ratio [OR]: 2.992; 95% confidence intervals [CI] 2.069-4.327). Anemia was also a predictor for vitamin D deficiency or insufficiency (OR: 3.16; 95% CI 2.02-4.92). Age was positively correlated with vitamin D levels (Pearson correlation=0.183, p<0.000). CONCLUSION: Vitamin D deficiency is common in healthy Saudi adults. This is more pronounced in females and in the younger age groups. Wearing of traditional clothes, deliberate avoidance of the sun, and inadequate dietary intake are likely to be the principal causes of low vitamin D levels.

Epidemiology and risk factors of chronic kidney disease in India - results from the SEEK (Screening and Early Evaluation of Kidney Disease) study.

BACKGROUND: There is a rising incidence of chronic kidney disease that is likely to pose major problems for both healthcare and the economy in future years. In India, it has been recently estimated that the age-adjusted incidence rate of ESRD to be 229 per million population (pmp), and >100,000 new patients enter renal replacement programs annually. METHODS: We cross-sectionally screened 6120 Indian subjects from 13 academic and private medical centers all over India. We obtained personal and medical history data through a specifically designed questionnaire. Blood and urine samples were collected. RESULTS: The total cohort included in this analysis is 5588 subjects. The mean ± SD age of all participants was 45.22 ± 15.2 years (range 18-98 years) and 55.1% of them were males and 44.9% were females. The overall prevalence of CKD in the SEEK-India cohort was 17.2% with a mean eGFR of 84.27 ± 76.46 versus 116.94 ± 44.65 mL/min/1.73 m2 in non-CKD group while 79.5% in the CKD group had proteinuria. Prevalence of CKD stages 1, 2, 3, 4 and 5 was 7%, 4.3%, 4.3%, 0.8% and 0.8%, respectively. CONCLUSION: The prevalence of CKD was observed to be 17.2% with ~6% have CKD stage 3 or worse. CKD risk factors were similar to those reported in earlier studies.It should be stressed to all primary care physicians taking care of hypertensive and diabetic patients to screen for early kidney damage. Early intervention may retard the progression of kidney disease. Planning for the preventive health policies and allocation of more resources for the treatment of CKD/ESRD patients are imperative in India.

Modulation of platelet activation in chronic kidney disease patients on erythropoiesis-stimulating agents.

BACKGROUND: Clinical trials demonstrate either no benefit or increased risk of cardiovascular events and mortality in patients with chronic kidney disease (CKD) targeted for higher hemoglobin levels, who are treated with erythropoiesis-stimulating agents (ESAs). The mechanism underlying this observation remains unexplained. METHODS AND RESULTS: We assessed platelet activation by measuring soluble P-selectin (sPsel), CD40 ligand (CD40L), and circulating microparticles (CMP) in patients with CKD. Higher hemoglobin levels were associated with increased Psel levels in patients on ESAs but not in ESA-naïve anemic and nonanemic patients. Psel positively correlated with CMP and CD40L in both anemic and nonanemic patients. Multivariate linear regression analysis revealed an association between increased Psel levels and hemoglobin concentration in patients receiving ESAs. CONCLUSIONS: Anemic CKD patients on ESAs demonstrate increased levels of markers of platelet activation. These observations suggest a potentially complex interplay between platelet activation, impaired kidney function, and treatment of CKD anemia with ESAs.

Epidemiology of chronic kidney disease in the Kingdom of Saudi Arabia (SEEK-Saudi investigators) - a pilot study.

There are no available data about the prevalence of chronic kidney disease (CKD) and its risk factors in the general population of the kingdom of Saudi Arabia. To estimate the prevalence of CKD and its associated risk factors in the Saudi population, we conducted a pilot community-based screening program in commercial centers in Riyadh, Saudi Arabia. Candidates were interviewed and blood and urine samples were collected. Participants were categorized to their CKD stage according to their estimated Modification of Diet in Renal Disease (MDRD3)-based, the new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and the presence of albuminuria. The sample comprised 491 (49.9% were males) adult Saudi nationals. The mean age was 37.4 ± 11.3 years. The over-all prevalence of CKD was 5.7% and 5.3% using the MDRD-3 and CKD-EPI glomerular filtration equations, respectively. Gender, age, smoking status, body mass index, hypertension and diabetes mel-litus were not significant predictors of CKD in our cohort. However, CKD was significantly higher in the older age groups, higher serum glucose, waist/hip ratio and blood pressure. Only 7.1% of the CKD patients were aware of their CKD status, while 32.1% were told that they had protein or blood in their urine and 10.7% had known kidney stones in the past. We conclude that prevalence of CKD in the young Saudi population is around 5.7%. Our pilot study demonstrated the feasibility of screening for CKD. Screening of high-risk individuals is likely to be the most cost-effective strategy to detect CKD patients.

Hypertension in the developing world: challenges and opportunities.

Hypertension is a major public health problem and a leading cause of death and disability in developing countries. One-quarter of the world's adult population has hypertension, and this is likely to increase to 29% by 2025. Modeled projections indicate an increase to 1.15 billion hypertensive patients by 2025 in developing countries. There is variability in the global prevalence of hypertension: hypertension is present in approximately 35% of the Latin American population, 20%-30% of the Chinese and Indian population, and approximately 14% in Sub-Saharan African countries. This heterogeneity has been attributed to several factors, including urbanization with its associated changes in lifestyle, racial ethnic differences, nutritional status, and birth weight. Compounding this high burden of hypertension is a lack of awareness and insufficient treatment in those with hypertension. The public health response to this challenge should drive greater promotion of awareness efforts, studies of risk factors for hypertension, and understanding of the impact of lifestyle changes. Also important are efforts to develop multipronged strategies for hypertension management in developing nations.

A prospective evaluation of renal replacement therapy modality eligibility.

BACKGROUND: Patient eligibility for renal replacement therapy (RRT) modalities is frequently debated, but little prospective data are available from large patient cohorts. METHODS: We prospectively evaluated medical and psychosocial eligibility for the three RRT modalities in patients with chronic kidney disease (CKD) stages III-V who were enrolled in an ongoing prospective cohort study conducted at seven North American nephrology practices. RESULTS: Ninety-eight percent of patients were considered medically eligible for haemodialysis (HD), 87% of patients were assessed as medically eligible for peritoneal dialysis (PD) and 54% of patients were judged medically eligible for transplant. Age was the leading cause of non-eligibility for both PD and transplant. Anatomical concerns (adhesions, hernias) were the second most frequent concern for PD eligibility followed by weight. Weight was also a concern for transplant eligibility. The proportion of patients medically eligible for RRT did not vary by CKD stage. There was, however, significant inter-centre variation in the proportion of patients medically eligible for PD and transplant. Ninety-five percent of patients were considered psychosocially eligible for HD, 83% of patients were assessed as psychosocially eligible for PD and 71% of patients were judged psychosocially eligible for transplant. The percentage of patients who were assessed as having neither medical nor psychosocial contraindications for RRT was 95% for HD, 78% for PD and 53% for transplant. CONCLUSIONS: Most CKD patients are considered by their medical care providers to be suitable for PD. Enhanced patient education, promotion of home dialysis for suitable patients and empowerment of patient choice are expected to augment growth of home dialysis modalities.

Endothelial activation markers in anemic non-dialysis chronic kidney disease patients.

BACKGROUND/AIMS: Anemia in chronic kidney disease is an independent predictor of cardiovascular disease (CVD). We explored the relationship between anemia and markers of inflammation and endothelial activation in non-dialysis chronic kidney disease (ND-CKD) patients to understand this mechanism. METHODS: Cross-sectional analysis was performed on 30 adult ND-CKD patients for markers of inflammation and endothelial activation using a multiplexed immunoassay. Data were analyzed according to the anemic status defined by the modified World Health Organization criteria. RESULTS: Seventeen patients were classified as anemic. Baseline characteristics by anemic status were similar except that anemic patients were older (p = 0.006), had lower estimated glomerular filtration rate (eGFR; p = 0.01) and higher prevalence of CVD (p = 0.02). Compared to non-anemic patients, log-transformed values of fibrinogen (p = 0.012); von Willebrand factor (vWF, p = 0.008), vascular cell adhesion molecule-1 (VCAM-1, p = 0.025) and C-reactive protein (p = 0.043) were elevated in anemic patients. Serum ferritin (p = 0.93) and serum albumin (p = 0.06) were not different. Age and eGFR-adjusted logistic regression analysis showed that anemic patients had increased odds for a composite of higher median values of fibrinogen, vWF and VCAM-1 (p = 0.01, odds ratio 8.1, 95% CI 1.08-111.0). CONCLUSION: We report the association of anemia with elevated markers of endothelial activation in ND-CKD patients. Longitudinal studies are needed to confirm our findings.

Association of anemia and erythropoiesis stimulating agents with inflammatory biomarkers in chronic kidney disease.

Inflammatory cytokines are important predictors of cardiovascular mortality especially in patients with chronic kidney disease. Here we explored the relationship of anemia and epoetin treatment to inflammatory cytokine levels in patients with chronic kidney disease. One hundred non-dialysis patients with chronic kidney disease over 18 years of age were evenly split into anemic and non-anemic cohorts. Of the 50 anemic patients, 23 were receiving erythropoiesis stimulating agents treatments. Levels of tumor necrosis factor (TNF)-alpha were found to be significantly higher and serum albumin was significantly lower with trends towards higher interleukin (IL)-6 and IL-8 in anemic compared to non-anemic patients. Further analysis by multiple logistic regression found that anemic patients treated with erythropoiesis stimulating agents had significantly higher odds for the upper two quartiles for IL-6, IL-8 and TNF-alpha compared to non-anemic patients. Our study found that the anemia of chronic kidney disease was associated with up regulation of TNF-alpha, and possibly IL-6 and IL-8 along with increased levels of these proinflammatory cytokines in patients treated with epoetin.