No large-scale studies have investigated the association between salt intake and hypertension in Korean population. To investigate the relationship of blood pressure to salt consumption, we analyzed data from 19,476 participants in the 2009-2011 Korean National Health and Nutritional Examination Survey (KNHANES). Urinary sodium excretion over 24-hr (24HUNa) was estimated from spot urine tests using Tanaka's equation. The study subjects were stratified into hypertensive and normotensive groups. Hypertensive participants (n=6,552, 33.6%) had higher estimated 24HUNa, 150.4+/-38.8 mEq/day, than normotensive participants, 140.5+/-34.6 mEq/day (P<0.001). The association between 24HUNa and blood pressure outcomes was not affected by adjustment for other risk factors for hypertension (odds ratio 0.001; 95% confidence interval 0.001-0.003; P<0.001). Increases in 24HUNa of 100 mEq/day were associated with a 6.1+/-0.3/2.9+/-0.2 mmHg increase in systolic/diastolic blood pressure in all participants. This effect was stronger in hypertensive participants (increase of 8.1+/-0.5/3.4+/-0.3 mmHg per 100 mEq/day) and smaller in normotensive participants (2.9+/-0.3/1.3+/-0.2 mmHg). These results support recommendations for low salt intake in Korean population to prevent and control adverse blood pressure levels.
Adult ; Algorithms ; Asian Continental Ancestry Group ; Blood Pressure/*physiology ; Demography ; Female ; Humans ; Hypertension/epidemiology/*urine ; Logistic Models ; Male ; Middle Aged ; Nutrition Surveys ; Prevalence ; Republic of Korea/epidemiology ; Risk Factors ; Sodium, Dietary/*urine ; Urine Specimen Collection

INTRODUCTIONMicroalbuminuria is an early sign of kidney damage. The prevalence of microalbuminuria in Singapore has been reported to be 36.0%-48.5%. However, the prevalence of microalbuminuria reported in these studies was determined with one urine sample using a qualitative urine test. The aim of this study was to determine the prevalence of micro- and macroalbuminuria using a more stringent criterion of two positive quantitative urine albumin-creatinine ratio (ACR) tests.

METHODSWe conducted a cross-sectional study of patients with type 2 diabetes mellitus (T2DM) who were followed up at a primary care clinic in Singapore. Patients were diagnosed to have albuminuria if they had two positive ACR tests within a seven-month period.

RESULTSA total of 786 patients with T2DM met the study's inclusion criteria. 55.7% were already on an angiotensin-converting enzyme inhibitor (ACEI) and/or angiotensin receptor blocker (ARB). The prevalence rates of micro- and macroalbuminuria were 14.2% and 5.7%, respectively. Patients with albuminuria were more likely to have hypertension (odds ratio [OR] 3.47, 95% confidence interval [CI] 1.55-7.80). Diabetics with poorer diabetic control (OR 1.88, 95% CI 1.26-2.79), and higher systolic (OR 1.69, 95% CI 1.14-2.49) and diastolic (OR 1.96, 95% CI, 1.20 to 3.22) blood pressures were more likely to have albuminuria.

CONCLUSIONIn the present study, the prevalence of microalbuminuria is significantly lower than that previously reported in Singapore. The presence of hypertension, poor diabetic control and suboptimal blood pressure control are possible risk factors for albuminuria in patients with T2DM.

Aged ; Albuminuria ; complications ; epidemiology ; urine ; Blood Pressure ; Creatinine ; urine ; Cross-Sectional Studies ; Diabetes Complications ; epidemiology ; Diabetes Mellitus, Type 2 ; complications ; Female ; Humans ; Hypertension ; complications ; Male ; Middle Aged ; Odds Ratio ; Prevalence ; Primary Health Care ; Singapore ; Treatment Outcome

INTRODUCTIONClinical practice guidelines recommend using creatinine-based equations to estimate glomerular filtration rates (GFRs). While these equations were formulated for Caucasian-American populations and have adjustment coefficients for African-American populations, they are not validated for other ethnicities. The Chronic Kidney Disease-Epidemiology Collaborative Group (CKD-EPI) recently developed a new equation that uses both creatinine and cystatin C. We aimed to assess the accuracy of this equation in estimating the GFRs of participants (healthy and with chronic kidney disease [CKD]) from a multiethnic Asian population.

METHODSSerum samples from the Asian Kidney Disease Study and the Singapore Kidney Function Study were used. GFR was measured using plasma clearance of 99mTc-DTPA. GFR was estimated using the CKD-EPI equations. The performance of GFR estimation equations were examined using median and interquartile range values, and the percentage difference from the measured GFR.

RESULTSThe study comprised 335 participants (69.3% with CKD; 38.5% Chinese, 29.6% Malays, 23.6% Indians, 8.3% others), with a mean age of 53.5 ± 15.1 years. Mean standardised serum creatinine was 127 ± 86 μmol/L, while mean standardised serum cystatin C and mean measured GFR were 1.43 ± 0.74 mg/L and 67 ± 33 mL/min/1.73 m2, respectively. The creatinine-cystatin C CKD-EPI equation performed the best, with an estimated GFR of 67 ± 35 mL/min/1.73 m2.

CONCLUSIONThe new creatinine-cystatin C equation estimated GFR with little bias, and had increased precision and accuracy in our multiethnic Asian population. This two-biomarker equation may increase the accuracy of population studies on CKD, without the need to consider ethnicity.

Adult ; Aged ; Body Mass Index ; China ; ethnology ; Female ; Healthy Volunteers ; Hospitals, University ; Humans ; Hypertension ; epidemiology ; India ; ethnology ; Linear Models ; Malaysia ; ethnology ; Male ; Middle Aged ; Prospective Studies ; Renal Insufficiency, Chronic ; ethnology ; urine ; Sodium, Dietary ; urine

OBJECTIVESalt-sensitivity plays an important role in essential hypertension and is associated with more severe target organ injury and higher mortality in patients with essential hypertension. However, the pathologic mechanism of salt-sensitivity is poorly understood and endothelial dysfunction might be involved in salt-sensitive hypertension. We, therefore, observed the endothelial function changes by measuring plasma and urine nitric oxide (NO) concentrations in salt-sensitive (SS) normotensive and mild hypertensive subjects underwent various salt loading protocols and the effects of potassium supplement.

METHODSThirty-nine normotensive and mild hypertensive subjects (< 160/100 mm Hg), aged 16-60, were enrolled and the study protocol is as follows: 3 days baseline investigation, 1 week low-salt loading (3 g/day), 1 week. high-salt loading (18 g/day) and 1 week high-salt loading plus potassium chloride (4.5 g/day).

RESULTSPlasma and urine NO levels were significantly lower in SS (n = 8) subjects at baseline, low-salt and high-salt loading phases compared with salt-resistant subjects (SR, n = 31) and oral potassium supplement to SS subjects with high salt loading significantly increased plasma and urine NO levels.

CONCLUSIONEndothelial function is impaired in normotensive and mild hypertensive SS subjects. Oral potassium supplement could improve endothelial function in normotensive and mild hypertensive SS subjects.

Adult ; Antihypertensive Agents ; Blood Pressure ; Endothelium ; physiology ; Female ; Humans ; Hypertension ; epidemiology ; physiopathology ; Male ; Nitric Oxide ; blood ; urine ; Potassium, Dietary ; administration & dosage

This study was aimed to evaluate the agreement between the self-reported sodium intake level and 24-h urine sodium excretion level in Chinese. The 24-h urine collection was conducted among 2112 adults aged 18-69 years randomly selected in Shandong Province, China. The subjects were asked whether their sodium intake was low, moderate, or high. The weighted kappa statistics was calculated to assess the agreement between 24-h urine sodium excretion level and self-reported sodium intake level. One third of the subjects reported low sodium intake level. About 70% of the subjects had mean 24-h sodium excretion>9 g/d, but reported low or moderate sodium intake. The agreement between self-reported sodium intake level and 24-h urine sodium excretion level was low in both normotensive subjects and hypertensive subjects. These findings suggested that many subjects who reported low sodium intake had actual urine sodium excretion>9 g/d. Sodium intake is often underestimated in both hypertensive and normotensive participants in China.
Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; Awareness ; China ; epidemiology ; Diet Records ; Diet Surveys ; Diet, Sodium-Restricted ; Female ; Health Knowledge, Attitudes, Practice ; Humans ; Hypertension ; epidemiology ; prevention & control ; Male ; Rural Population ; Sodium ; urine ; Sodium Chloride ; adverse effects ; Sodium, Dietary ; administration & dosage ; Surveys and Questionnaires ; Young Adult

We have hypothesized that non-dipper status and left ventricular hypertrophy (LVH) are associated with the development of chronic kidney disease (CKD) in non-diabetic hypertensive patients. This study included 102 patients with an estimated glomerular filtration rate (eGFR) > or = 60 mL/min/1.73 m2. Ambulatory blood pressure monitoring and echocardiography were performed at the beginning of the study, and the serum creatinine levels were followed. During the average follow-up period of 51 months, CKD developed in 11 patients. There was a significant difference in the incidence of CKD between dippers and non-dippers (5.0% vs 19.0%, P < 0.05). Compared to patients without CKD, patients with incident CKD had a higher urine albumin/creatinine ratio (52.3 +/- 58.6 mg/g vs 17.8 +/- 29.3 mg/g, P < 0.01), non-dipper status (72.7% vs 37.4%, P < 0.05), the presence of LVH (27.3% vs 5.5%, P < 0.05), and a lower serum HDL-cholesterol level (41.7 +/- 8.3 mg/dL vs 50.4 +/- 12.4 mg/dL, P < 0.05). Based on multivariate Cox regression analysis, non-dipper status and the presence of LVH were independent predictors of incident CKD. These findings suggest that non-dipper status and LVH may be the therapeutic targets for preventing the development of CKD in non-diabetic hypertensive patients.
Adult ; Aged ; Aged, 80 and over ; Albumins/analysis ; Blood Pressure ; Blood Pressure Monitoring, Ambulatory ; Cholesterol, HDL/blood ; Chronic Disease ; Creatinine/blood/urine ; Cross-Sectional Studies ; Female ; Follow-Up Studies ; Glomerular Filtration Rate ; Humans ; Hypertension/complications ; Hypertrophy, Left Ventricular/complications/*diagnosis ; Incidence ; Kidney Diseases/epidemiology/*etiology/ultrasonography ; Male ; Middle Aged ; *Predictive Value of Tests ; Retrospective Studies