Prepubertal duration of diabetes and prepubertal hyperglycemia contribute to the risk of postpubertal MA. The differences in rates of development of MA relating to HbAlc, sex, and age at diagnosis relative to puberty may have long-term consequences for the risk of subsequent nephropathy and for cardiovascular risk.

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Abstract-A reduction in salt intake lowers blood pressure. However, most previous trials were in whites with few in blacks and Asians. Salt reduction may also reduce other cardiovascular risk factors (eg, urinary albumin excretion, arterial stiffness). However, few well-controlled trials have studied these effects. We carried out a randomized double-blind crossover trial of salt restriction with slow sodium or placebo, each for 6 weeks, in 71 whites, 69 blacks, and 29 Asians with untreated mildly raised blood pressure. From slow sodium to placebo, urinary sodium was reduced from 165Ϯ58 (ϮSD) to 110Ϯ49 mmol/24 hours (9.7 to 6.5 g/d salt). With this reduction in salt intake, there was a significant decrease in blood pressure from 146Ϯ13/91Ϯ8 to 141Ϯ12/88Ϯ9 mm Hg (PϽ0.001), urinary albumin from 10.2 (IQR: 6.8 to 18.9) to 9.1 (6.6 to 14.0) mg/24 hours (PϽ0.001), albumin/creatinine ratio from 0.81 (0.47 to 1.43) to 0.66 (0.44 to 1.22) mg/mmol (PϽ0.001), and carotid-femoral pulse wave velocity from 11.5Ϯ2.3 to 11.1Ϯ1.9 m/s (PϽ0.01). Subgroup analysis showed that the reductions in blood pressure and urinary albumin/creatinine ratio were significant in all groups, and the decrease in pulse wave velocity was significant in blacks only. These results demonstrate that a modest reduction in salt intake, approximately the amount of the current public health recommendations, causes significant falls in blood pressure in all 3 ethnic groups. Furthermore, it reduces urinary albumin and improves large artery compliance. Although both could be attributable to the falls in blood pressure, they may carry additional benefits on reducing cardiovascular disease above that obtained from the blood pressure falls alone. Key Words: salt reduction Ⅲ blood pressure Ⅲ ethnic group Ⅲ urinary albumin Ⅲ pulse wave velocity T here is much evidence from epidemiological, migration, intervention, treatment, genetic, and animal studies that dietary salt (sodium chloride) plays an important role in regulating blood pressure (BP), and our current high salt intake is largely responsible for the rise in BP with age. 1 Many randomized trials have demonstrated that a modest reduction in salt intake lowers BP. 2 However, most previous trials were carried out in white individuals. There were only very limited number of trials in blacks 3,4 and even fewer in Asians.Increasing evidence suggests that a lower salt intake may have other beneficial effects (eg, reducing urinary albumin excretion, 5,6 decreasing arterial stiffness as measured by pulse wave velocity 7 ). The evidence for these other effects is mainly from epidemiological and animal studies. Few wellcontrolled trials have studied whether a modest reduction in salt intake has such effects in humans.The average salt intake, as measured by 24-hour urinary sodium, was 8.6 g/d (equivalent to 3.4 g sodium) for adults in the UK according a recent survey in 2008. 8 However, at the time when our study protocol was developed, it was 9.5 g/d, 9 which is very similar to the current salt intake in most countries...

Abstract-To determine the effects of potassium supplementation on endothelial function, cardiovascular risk factors, and bone turnover and to compare potassium chloride with potassium bicarbonate, we carried out a 12-week randomized, double-blind, placebo-controlled crossover trial in 42 individuals with untreated mildly raised blood pressure. Urinary potassium was 77Ϯ16, 122Ϯ25, and 125Ϯ27 mmol/24 hours after 4 weeks on placebo, potassium chloride, and potassium bicarbonate, respectively. There were no significant differences in office blood pressure among the 3 treatment periods, and only 24-hour and daytime systolic blood pressures were slightly lower with potassium chloride. Compared with placebo, both potassium chloride and potassium bicarbonate significantly improved endothelial function as measured by brachial artery flow-mediated dilatation, increased arterial compliance as assessed by carotid-femoral pulse wave velocity, decreased left ventricular mass, and improved left ventricular diastolic function. There was no significant difference between the 2 potassium salts in these measurements. The study also showed that potassium chloride reduced 24-hour urinary albumin and albumin:creatinine ratio, and potassium bicarbonate decreased 24-hour urinary calcium, calcium:creatinine ratio, and plasma C-terminal cross-linking telopeptide of type 1 collagen significantly. These results demonstrated that an increase in potassium intake had beneficial effects on the cardiovascular system, and potassium bicarbonate may improve bone health. Importantly, these effects were found in individuals who already had a relatively low-salt and high-potassium intake. (Hypertension. 2010;55:681-688.)Key Words: potassium chloride Ⅲ potassium bicarbonate Ⅲ endothelial function Ⅲ cardiovascular risk factors Ⅲ bone turnover Ⅲ randomized trial M any randomized trials have shown that an increase in potassium intake lowers blood pressure (BP), particularly in individuals with raised BP. 1 Increasing evidence also suggests that a higher potassium intake may have beneficial effects on endothelial function, renal disease, arterial compliance, left ventricular (LV) mass and function, and bone mineral density. 2 The evidence for many of these effects is mainly from experimental studies in animals, and few wellcontrolled trials have studied such effects in humans.Most previous studies on potassium have used potassium chloride, which is convenient for making the study double blinded by using slow-release potassium chloride versus slow-release potassium chloride placebo. 1 These studies have demonstrated clear benefits of potassium chloride, particularly on BP. Increasing potassium intake has been recommended as an important approach to lowering BP not only in individuals with raised BP but also in those with normal BP. However, no one is suggesting that the whole population take potassium chloride supplements. The best way to increase potassium intake is to increase the consumption of foods that are high in potassium, for example, fruit and ve...

BACKGROUND Standardized calibration does not change a creatinine measurement procedure's susceptibility to potentially interfering substances. METHODS We obtained individual residual serum or plasma samples (n = 365) from patients with 19 different disease categories associated with potentially interfering substances and from healthy controls. Additional sera at 0.9 mg/dL (80 μmol/L) and 3.8 mg/dL (336 μmol/L) creatinine were supplemented with acetoacetate, acetone, ascorbate, and pyruvate. We measured samples by 4 enzymatic and 3 Jaffe commercially available procedures and by a liquid chromatography/isotope dilution/mass spectrometry measurement procedure against which biases were determined. RESULTS The number of instances when 3 or more results in a disease category had biases greater than the limits of acceptability was 28 of 57 (49%) for Jaffe and 14 of 76 (18%) for enzymatic procedures. For the aggregate group of 59 diabetes samples with increased β-hydroxybutyrate, glucose, or glycosylated hemoglobin (Hb A1c), the enzymatic procedures had 10 biased results of 236 (4.2%) compared with 89 of 177 (50.3%) for the Jaffe procedures, and these interferences were highly procedure dependent. For supplemented sera, interferences were observed in 11 of 24 (46%) of groups for Jaffe and 8 of 32 (25%) of groups for enzymatic procedures and were different at low or high creatinine concentrations. CONCLUSIONS There were differences in both magnitude and direction of bias among measurement procedures, whether enzymatic or Jaffe. The influence of interfering substances was less frequent with the enzymatic procedures, but no procedure was unaffected. The details of implementation of a method principle influenced its susceptibility to potential interfering substances.

OBJECTIVE -To explore the prevalence of lipid abnormalities and their relationship with albumin excretion and microalbuminuria in adolescents with type 1 diabetes.RESEARCH DESIGN AND METHODS -The study population comprised 895 young subjects with type 1 diabetes (490 males); median age at the baseline assessment was 14.5 years (range 10 -21.1), and median diabetes duration was 4.8 years (0.2-17). A total of 2,194 nonfasting blood samples were collected longitudinally for determination of total cholesterol, LDL cholesterol, HDL cholesterol, TG, and non-HDL cholesterol. Additional annually collected data on anthropometric parameters, A1C, and albumin-to-creatinine ratio (ACR) were available.RESULTS -Total cholesterol, LDL cholesterol, HDL cholesterol, and non-HDL cholesterol were higher in females than in males (all P Ͻ 0.001). A significant proportion of subjects presented sustained lipid abnormalities during follow-up: total cholesterol Ͼ5.2 mmol/l (18.6%), non-HDL cholesterol Ͼ3.4 mmol/l (25.9%), TG Ͼ1.7 mmol/l (20.1%), and LDL cholesterol Ͼ3.4 mmol/l (9.6%). Age and duration were significantly related to all lipid parameters (P Ͻ 0.001); A1C was independently related to all parameters (P Ͻ 0.001) except HDL cholesterol, whereas BMI SD scores were related to all parameters (P Ͻ 0.05) except total cholesterol. Total cholesterol and non-HDL cholesterol were independently related to longitudinal changes in ACR (B coefficient Ϯ SE): 0.03 Ϯ 0.01/1 mmol/l, P ϭ 0.009, and 0.32 Ϯ 0.014/1 mmol/l, P ϭ 0.02, respectively. Overall mean total cholesterol and non-HDL cholesterol were higher in microalbuminuria positive (n ϭ 115) than in normoalbuminuric subjects (n ϭ 780): total cholesterol 4.7 Ϯ 1.2 vs. 4.5 Ϯ 0.8 mmol/l (P ϭ 0.04) and non-HDL cholesterol 3.2 Ϯ 1.2 vs. 2.9 Ϯ 0.8 mmol/l (P ϭ 0.03).CONCLUSIONS -In this longitudinal study of adolescents with type 1 diabetes, sustained lipid abnormalities were related to age, duration, BMI, and A1C. Furthermore, ACR was related to both total cholesterol and non-HDL cholesterol, indicating a potential role in the pathogenesis of diabetic nephropathy.

OBJECTIVETo assess the potential association between A1C variability (A1C-SD) and microalbuminuria in young people with type 1 diabetes.RESEARCH DESIGN AND METHODSSerially collected samples for A1C measurement were available for 1,232 subjects with childhood-onset type 1 diabetes recruited to the Oxford Regional Prospective Study and the Nephropathy Family Study.RESULTSThe median (range) number of A1C assessments was 4 (2–16). Mean intrapersonal A1C was 9.5% and A1C-SD was 0.91. Mean A1C and A1C-SD values were higher in subjects with microalbuminuria (n = 227) than in those with normoalbuminuria (10.3 vs. 9.4%; 1.12 vs. 0.86, P < 0.001). In a Cox regression model, A1C-SD was independently associated with microalbuminuria (hazard ratio 1.31 [95% CI 1.01–1.35]).CONCLUSIONSIn the current study, A1C variability was an independent variable that added to the effect of A1C on the risk for microalbuminuria in youth with type 1 diabetes, a population highly vulnerable to vascular complications.

SummaryBackground and objectives Heart disease is a major cause of death in young adults with chronic kidney disease (CKD). Left ventricular hypertrophy (LVH) is common and is associated with hypertension. The aims of this study were to evaluate whether there is a relationship between LVH and BP in children with CKD and whether current targets for BP control are appropriate.Design, setting, participants, & measurements In this single-center cross-sectional study, 49 nonhypertensive children, (12.6 Ϯ 3.0 years, mean GFR 26.1 Ϯ 12.9 ml/min per 1.73 m 2 ) underwent echocardiographic evaluation and clinic and 24-hour ambulatory BP monitoring. LVH was defined using age-specific reference intervals for left ventricular mass index (LVMI). Biochemical data and clinic BP for 18 months preceding study entry were also analyzed. ResultsThe mean LVMI was 37.8 Ϯ 9.1 g/m 2.7 , with 24 children (49%) exhibiting LVH. Clinic BP values were stable over the 18 months preceding echocardiography. Patients with LVH had consistently higher BP values than those without, although none were overtly hypertensive (Ͼ95th percentile). Multiple linear regression demonstrated a strong relationship between systolic BP and LVMI. Clinic systolic BP showed a stronger relationship than ambulatory measures. Of the confounders evaluated, only elemental calcium intake yielded a consistent, positive relationship with LVMI.Conclusions LVMI was associated with systolic BP in the absence of overt hypertension, suggesting that current targets for BP control should be re-evaluated. The association of LVMI with elemental calcium intake questions the appropriateness of calcium-based phosphate binders in this population.