RESUMO
Decreasing sodium intake has been associated with improvements in blood pressure (BP) and proteinuria, two important risk factors for CVD and chronic kidney disease (CKD) progression. We aimed to investigate the role of sodium intake by examining the effect of changes in sodium intake over 1 year on BP and proteinuria in people with early stage CKD. From thirty-two general practices, 1607 patients with previous estimated glomerular filtration rate of 59-30 ml/min per 1.73 m² and mean age of 72.9 (sd 9.0) years were recruited. Clinical assessment, urine and serum biochemistry testing were performed at baseline and after 1 year. Sodium intake was estimated from early morning urine specimens using an equation validated for this study population. We found that compared with people who increased their sodium intake from ≤ 100 to >100 mmol/d over 1 year, people who decreased their intake from >100 to ≤ 100 mmol/d evidenced a greater decrease in all BP variables (Δmean arterial pressure (ΔMAP) = -7.44 (SD 10.1) v. -0.23 (SD 10.4) mmHg; P<0.001) as well as in pulse wave velocity (ΔPWV = -0.47 (SD 1.3) v. 0.08 (SD 1.88) m/s; P<0.05). Albuminuria improved only in albuminuric patients who decreased their sodium intake. BP improved in people who maintained low sodium intake at both times and in those with persistent high intake, but the number of anti-hypertensive increased only in the higher sodium intake group, and PWV improved only in participants with lower sodium intake. Decreasing sodium intake was an independent determinant of ΔMAP. Although more evidence is needed, our results support the benefits of reducing and maintaining sodium intake below 100 mmol/d (2.3-2.4 g/d) in people with early stages of CKD.
Assuntos
Dieta Hipossódica , Hipertensão Renal/prevenção & controle , Cooperação do Paciente , Insuficiência Renal Crônica/dietoterapia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Terapia Combinada , Progressão da Doença , Inglaterra/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão Renal/epidemiologia , Hipertensão Renal/etiologia , Perda de Seguimento , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Atenção Primária à Saúde , Estudos Prospectivos , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/urina , Fatores de Risco , Índice de Gravidade de Doença , Sódio/urinaRESUMO
OBJECTIVE: To comparatively examine the effects of adiposity on the levels of plasma renin activity (PRA), plasma aldosterone concentration (PAC), and aldosterone-renin ratio (ARR) in young black and white children. STUDY DESIGN: We prospectively assessed 248 black and 345 white children and adolescents. A novel analytical technique was used to assess the concurrent influences of age and body mass index (BMI) on PRA, PAC, and ARR. The estimated effects were depicted by colored contour plots. RESULTS: In contrast to whites, blacks had lower PRA (2.76 vs 3.36 ng/mL/h; P < .001) and lower PAC (9.01 vs 14.59 ng/dL; P < .001). In blacks, BMI was negatively associated with PRA (P = .001), consistent with an association with a more expanded plasma volume; there was no association with PAC. In whites, BMI was positively associated with PAC (P = .005); we did not detect a BMI-PRA association. The effects of BMI on ARR were directionally similar in the two race groups but more pronounced in blacks. Mean systolic blood pressure was greater in blacks with lower PRA (P < .01), higher PAC (P = .015), and higher ARR (P = .49). CONCLUSIONS: An increase in adiposity was associated with a suppressed PRA in blacks and an increase in PAC in whites. The unique relationship between adiposity and renin-aldosterone axis in blacks suggests the possible existence of a population-specific mechanism characterized by volume expansion, which could in turn enhance the influences of adiposity on blood pressure in black children and adolescents.
Assuntos
Adiposidade/etnologia , Pressão Sanguínea , Sistema Renina-Angiotensina , Adolescente , Negro ou Afro-Americano/etnologia , Fatores Etários , Aldosterona/sangue , Aldosterona/fisiologia , Índice de Massa Corporal , Feminino , Humanos , Masculino , Estudos Prospectivos , Radioimunoensaio/métodos , Renina/sangue , Renina/fisiologia , População Branca/etnologiaRESUMO
OBJECTIVE: To determine the relationship between repeat courses of antenatal corticosteroids (ACS) and risk factors for cardiovascular disease in adolescents and young adults. STUDY DESIGN: We assessed body mass index, blood pressure, arterial stiffness, blood lipids, and insulin resistance (IR) in a Swedish population-based cohort (n = 100) at a median age of 18 (range 14-26) years. Fifty-eight subjects (36 males) had been exposed to 2-9 weekly courses of antenatal betamethasone and 42 (23 males) were unexposed subjects matched for age, sex, and gestational age (GA). RESULTS: There were no significant differences between the groups regarding body mass index, systolic or diastolic blood pressures, arterial stiffness measured by augmentation index, blood lipids, IR, or morning cortisol levels either in simple regression or in multivariable models. However, more subjects with elevated augmentation index had been exposed to repeat courses of ACS (n = 7) compared with unexposed subjects (n =1, P = .06), and glucose, insulin, and IR correlated inversely to GA at start of ACS (P < .01). CONCLUSIONS: Repeat courses of ACS did not correlate to adverse cardiovascular risk profile in adolescence and young adulthood, but long-standing effects on the arterial tree and glucose metabolism, the latter dependent on GA at ACS exposure, cannot be excluded. These observations have clinical implications for the ongoing discussion on short-term benefits and long-term safety of repeat ACS treatment.
Assuntos
Anti-Inflamatórios/efeitos adversos , Betametasona/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Resistência à Insulina , Lipídeos/sangue , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Rigidez Vascular/efeitos dos fármacos , Adolescente , Adulto , Anti-Inflamatórios/administração & dosagem , Betametasona/administração & dosagem , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Esquema de Medicação , Feminino , Humanos , Modelos Lineares , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Adulto JovemRESUMO
OBJECTIVE: To examine associations of urinary phthalate levels with blood pressure (BP) and serum triglyceride and lipoprotein levels in children. STUDY DESIGN: We performed a cross-sectional analysis of a subsample of US children aged 6-19 years who participated in the National Health and Nutrition Examination Survey between 2003 and 2008. We quantified exposure to 3 families of phthalates--low molecular weight, high molecular weight and di-2-ethylhexylphthalate (DEHP)--based on molar concentration of urinary metabolites. We assessed descriptive, bivariate, and multivariate associations with BP and lipid levels. RESULTS: Controlling for an array of sociodemographic and behavioral factors, as well as diet and body mass index, levels of metabolites of DEHP, a phthalate commonly found in processed foods, were associated with higher age-, sex-, and height-standardized BP. For each log unit (roughly 3-fold) increase in DEHP metabolites, a 0.041 SD unit increase in systolic BP z-score was identified (P = .047). Metabolites of low molecular weight phthalates commonly found in cosmetics and personal care products were not associated with BP. Phthalate metabolites were not associated with triglyceride levels, high-density lipoprotein level, or prehypertension. CONCLUSIONS: Dietary phthalate exposure is associated with higher systolic BP in children and adolescents. Further work is needed to confirm these associations, as well as to evaluate opportunities for intervention.